CH643846A5 - Antibacterial penem compounds - Google Patents

Abstract

A description is given of the novel compounds of the formula I and of their pharmaceutically usable salts. The meanings of the substituents A, Alk, Alk', R20, Y and Z are as defined in Claim 1. These are active antibacterial agents and can also be used as starting substances for the preparation of other such agents. They are obtained by cyclising compounds of the formula II in which Y, Q, R'' and T have the meaning given in Claim 5. <IMAGE>

Description

The present invention relates to new 2-substituted and 2,6-disubstituted penem compounds with a pronounced antibiotic effect. Also included are methods of making these active compounds. The penem ring system has the formula

O 7 1

and can be systematically called 7-oxo-4-thia-l-azabicyclo- [3.2.0] hept-2-ene. For the sake of simplicity, this compound is referred to as "2-penem" in the present description and the numbering of the individual atoms is as follows:

The present invention accordingly provides new 2,6-di-substituted penemes of the formula

I.

, (Alk) -A- {Alk ') - R20

N '//

wherein A, Alk, Alk ', R2o, Y and Z are as defined in claim 1, or a pharmaceutically acceptable salt thereof.

The compounds of formula I wherein Z is hydrogen (and their pharmaceutically acceptable salts and physiologically hydrolyzable esters) are effective antibacterial agents. The other compounds are useful precursors to the biologically active penems.

The above-mentioned substituents for the 2- and 6-positions of the Penem ring system can be described in more detail as follows:

(a) Halogen includes chlorine, bromine, fluorine and iodine. Preferred halogen substituents are chlorine or fluorine;

(b) (Lower) alkyl comprises both straight-chain and branched-chain saturated aliphatic hydrocarbon radicals with 1-6 C atoms included, e.g. Methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, etc. Preferred (lower) alkyl substituents have 1-4 C atoms and in particular 1-2 carbon atoms;

(c) (Lower) aliphatic includes acyclic straight-chain and branched-chain saturated and unsaturated hydrocarbon radicals with 1-6 C-atoms inclusive. The unsaturated radicals can contain one or more double or triple bonds, but preferably they contain a double or triple bond. Examples of (never) the aliphatic are methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, sec-butyl, n-pentyl, isobutyl, vinyl, 1-propenyl, 2-propenyl, isopropenyl , 2-methyl-2-propenyl, ethynyl and 2-propynyl. The most preferred aliphatic radicals are the (lower) alkyls according to (b);

(d) (Lower) cycloaliphatic stands for an alicyclic, saturated or unsaturated hydrocarbon radical with 3-8 ring carbon atoms, preferably 3-6 C atoms. The lounge-saturated ring may contain one or more (preferably one) double bonds. Examples of these groups are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclo-heptyl, cyclooctyl, cyclopropenyl, cyclopentenyl, 1,3-cyclohexadienyl and cyclohexenyl; 15 (e) (lower) cycloaliphatic (lower) aliphatic stands for cycloaliphatic-aliphatic radicals with 3-8 C atoms (preferably 3-6) in the cycloaliphatic ring and 1-6 C atoms (preferably 1-4 and in particular 1- 2) in the aliphatic part. Examples include cyclopropylmethyl, cy-20-propyl-ethyl, cyclopropylpentyl, cyclobutyl-ethyl, cyclopentyl-methyl, cyclohexyimethyl, cyclopropenyl-methyl, cyclopentenyl-ethyl, cyclopropyl-ethenyl, cyclopropyl-ethynyl, etc. The most preferred radicals of this type are cycloalkyl-alkyl, where the cycloalkyl-3-6 -Atoms and 25 the alkyl part contains 1-2 carbon atoms;

(f) (Lower) alkoxy stands for C] -C6 alkoxy radicals in which the alkyl part corresponds to the definition of (b). Examples are methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, n-pentyloxy, etc. are preferred

30C, -C4 alkoxy and especially Q-Q alkoxy;

(g) (Lower) alkylthio stands for Cj-Q-alkylthio radicals in which the alkyl part corresponds to the definition of (b). -

. games are methylthio, ethylthio and n-butylthio;

35 (h) (Lower) alkylamino includes C alkylamino radals, in which the alkyl portion corresponds to the definition of (b). Examples are methylamino, ethylamino, n-propylamino and n-butylamino;

(i) Di (lower) alkylamino stands for Cj-Q-alkylamino, 40 in which alkyl corresponds to the definition of (b). Examples include dimethylamino and diethylamino;

(j) (Lower) alkanoyloxy stands for radicals of the formula

O

II

45 (lower) alkyl-C-0-, where alkyl corresponds to the definition of (b);

(k) (Lower) alkanoyIamino includes radicals of the formula

O

II

50 (lower) alkyl-C-NH-, where alkyl corresponds to the definition of (b);

O

II

(1) carb (lower) alkoxy stands for -C- (lower) alkoxy wherein 55 (lower) alkoxy is as defined under (f);

(m) Halogen (lower) alkyl represents alkyl radicals in which one or more hydrogen atoms have been replaced by a halogen atom;

60 (n) sulfo (lower) alkyl represents - (CH2) nSO3H, where n is 1-6;

(o) carboxy (lower) alkyl represents- (CH2) nCOOH, where n is 1-6;

65

(p) phenyl (lower) alkyl represents - (CH2) n- ^ where n is 1-6;

643846

O

II

(q) (lower) alkanoyl stands for (lower) alkyl-C-, where alkyl is as defined under (b);

(r) N- (lower) alkylcarbamoyl stands for (lower) alk-

O

Ii yl-HN-C-, wherein alkyl is as defined under (b); (s) N, N-Di (lower) carbamoyl stands for O

(Lower alkyl ^ 11

^ N-C-, where each alkyl as in (b)

(Lower) alkyl is defined;

O

Î

(t) (Lower) alkylsulfinyl stands for-S- (lower) alkyl, in which (lower) alkyl is as defined under (b).

5 The term “heterocyclic” used in the present description stands for heteromonocyclic and heterobi-cyclic residues of aromatic character as well as for corresponding partially or completely saturated residues, these heterocyclic residues containing at least one heteroatom 10 such as oxygen, sulfur or nitrogen and via one Ring carbon atom are bound to the carbon atom in the Penem ring. The preferred heterocyclic groups are either 5- or 6-membered monocyclic radicals or 6,6- or 5,6-bicyclic radicals fused to one another. Illustrative examples of such heterocyclic radicals are the following:

O

'N-

H

E N.

f>

\ 1 N

LJL

> N

-CK

N

N H

N-

Il -î!

-N.

N E

N

'N H

N = N

/

N — N // \ =

• N

N

-N II

• N-

h n

II

n n n n n

JUJ

li il n

643846

-n 11

1 i

Nv.n ^ N

N

K-H

n

VN-H

■ n

-C

il

.N

H

and

30th

25th

In an analogous manner, the terms heterocyclic- (lower) alkyl, heterocyclic-thio- (lower) alkyl, heterocyclicoxy and heterocyclic-thio are the radicals - (CH2) n-heterocyclic, - (CH2) nS-heterocyclic, -O Heterocyclic and heterocyclic, where n is 1-6 (preferably 1 or 2).

Since an asymmetric carbon atom is present in the 2-substituted compounds of the formula I, such compounds can be either in the form of racemic mixtures (R, S form) or as individual right-handed or left-handed (R and S forms) optical isomers are available. The compounds in which the configuration on the 5-carbon atom corresponds to that of natural penicillin (5R configuration) are preferred. Substituents in the 5- and 6-positions of the 2,6-disubstituted penems can either be in the ice or trans position relative to one another. If the penem-6 substituent contains an asymmetric carbon atom, the corresponding isomers are identified as isomers A, B, C and D (see Example 5 for stereochemistry). The preferred isomers for compounds of this type 45 are those of type B. The different optical and geometric isomers can be separated in a conventional manner.

The present invention comprises the compounds of the formula I in the form of isomeric mixtures and also in the form of the individually separated and worked up isomers.

Said pharmaceutically acceptable salts include non-toxic salts of carboxylic acids, e.g. non-toxic metallic salts such as sodium, potassium, calcium, aluminum and magnesium salts, ammonium salts and salts with non-toxic amines such as trialkylamines (tri-ethylamine), procaine, dibenzylamine, N-benzyl-ß-phen- ethylamine, 1-ephenamine, N, N'-dibenzylethylenediamine, N-alkylpiperidine and other amines, as are customary for the formation of salts of penicillins and cephalosporins.

When a basic group is present, the present invention also encompasses acid addition salts, e.g. Salts with mineral acids such as hydrochloric acid, hydrobromic acid, hydroiodic acid, phosphoric acid, sulfuric acid or with suitable65 organic carboxylic acids or sulfonic acids such as trifluoroacetic acid, p-toluenesulfonic acid, maleic acid, acetic acid, Ci

55

60

tronic acid, oxalic acid, succinic acid, benzoic acid, tartaric acid, fumaric acid, mandelic acid, ascorbic acid and malic acid. Compounds containing an acidic group and a basic group may also be in the form of internal salts, i.e. as a zwitterion. The salts described can be prepared in a conventional manner, as is customary, to form salts of β-lactam antibiotics such as penicillins and cephalosporins.

The term “ester protecting group” has a clearly defined meaning in the chemistry of β-lactams and peptides. Many such groups are known and are introduced to protect a carboxyl group during chemical synthesis processes and can later be split off in a conventional manner to give the free carboxylic acids. Known ester protection groups are e.g. 2,2,2-trichloroethyl, tertiary alkyl with 4-6 C atoms, tertiary alkenyl with 5-7 C atoms, tertiary alkynyl with 5-7 C atoms, alkoxy-methyl, alkanoylmethyl with 2-7 C atoms , N-phthalimido-methyl, benzoylmethyl, halobenzoylmethyl, benzyl, p-nitrobenzyl, o-nitrobenzyl, benzhydryl, trityl, trimethylsilyl, triethylsilyl, ß-trimethylsilylethyl and the like.

The choice of an ester protecting group depends on the reaction conditions used below, under which the said group must not be split off, and on the conditions to be chosen for its splitting off. The selection of a suitable such group is unproblematic for the person skilled in the art. For use as an intermediate, the most preferred ester is the p-nitrobenzyl ester, which can be easily cleaved off by catalytic hydrogenation. For the preparation of compounds containing functional groups which can be reduced under such cleavage conditions, there is a preferred alternative in the β-trimethylsilyl ethyl group, which can be cleaved by treatment with fluoride ions. Also included in the aforementioned cleavable ester protecting groups are physiologically cleavable esters, i.e. such esters, as are known in penicillin and cephalosporin chemistry, which are split in the organism. Examples of such physiologically cleavable esters are indanyl, phthalidyl, methoxymethyl, glycyloxymethyl, phenylglycyloxymethyl, thienylglycyloxymethyl or acyloxymethyl of the formula

643 846

6

O

II

-CH2C-Y \

wherein Y 'represents Q-Q alkyl or phenyl. Particularly preferred esters of this type are methoxymethyl, acetoxymethyl, pivaloyloxymethyl, phthalidyl and indanyl.

The compounds of the formula I can exist in a wide variety of solvation states and both the completely anhydrous and the various solvated (including hydrates) states are encompassed by the present invention.

With respect to the compounds of Formula I, the preferred compounds are those in which Y is hydrogen or (lower) alkyl optionally substituted (preferably on the a-carbon) by hydroxy. More preferred are compounds of the group mentioned, in which Y is hydrogen, ethyl or a-hydroxyethyl. Even more preferred are compounds of formula I in which Y is hydrogen or a-hydroxyethyl and most preferred compounds are those in which Y is a-hydroxyethyl.

A preferred embodiment of the present invention are compounds of the formula I in which the 2-substituent

- (Alk) -O- (Alk ') - R20

is. Examples of such substituents are

-ch20ch2ch2nh2, -ch2ch20ch2ch2nh2,

-CH2OCH2CH2NHCH3,

-CH2OCH2CH2N (CH3) 2, -CH2OCH2CH2NHC2H5,

-CH2OCH2CH2N (C2H5) 2, -CH2OCH2CH2NHC3H7,

-CH2OCH2CH2N (C3H7) 2, -CH2OCH2CH2GH2NH2,

-CH2OCH2CH2CH2CH2NH2,

-CH2OCH2CH2CH2CH2NHCH3,

-CH2OCH2CH2CH2CH2N (CH3) 2,

-CH2CH2OCH2CH2NHCH3,

-CH2CH2OCH2CH2N (CH3) 2,

-CH2CH2OCH2CH2CH2NH2,

-CH2CH2OCH2CH2CH2NHCH3,

-CH2CH2OCH2CH2CH2N (CH3) 2,

-CH2CH-OCH2CH2NH2, -CH2CH-OCH2CH2NHCH3,

ch3 ch3

-ch2ch-och2ch2ch2n (ch3) 2, -ch2och2ch2nhoh,

c3h7

-CH2OCH2CH2CH2NHOH, CH2CH2OCH2CH2NHOH,

-ch2och2ch2no2, -ch2och2ch2ch2ch2no2, -ch2ch2och2ch2no2, -ch2c hoch2ch2nhoh,

I.

CH,

-CH2CH0CH2CH2N02 and c2H5

-CH2OCH2CH2CH2CH2NHOH.

The preferred compounds are those wherein Y is hydrogen, ethyl or a-hydroxyethyl and the most preferred members are Y is hydrogen or a-hydroxyethyl and especially Y is a-hydroxyethyl.

Another preferred embodiment of the present invention consists of compounds of the formula I in which the 2-substituent

- (Alk) -S- (Alk ') - R20

means. Examples of such substituents are -CH2SCH2CH2NH2, -CH2CH2SCH2CH2NH2, -CH2SCH2CH2CH2NH2, -CH2SCH2CH2CH2CH2NH2, -CH2SCH2CH2NHCH3, -CH2SCH2CH2N (CH3) 2, 5 -CH2SCH2CH2NHC2H5, -CH2SCH2CH2N (C2H5) 2, -CH2SCH2CH2NHC4H9, -CH2SCH2CH2N (C4H9) 2, -CH2SCH2CH2CH2NHCH3 , -CH2SCH2CH2CH2N (CH3) 2, -CH2SCH2CH2CH2N (C3H7) 2, -CH2SCH2CH2CH2CH2NHCH3, 10-CH2CH2SCH2CH2CH2NH2, -CH2CH2SCH2CH2NH2, -CH2CHSCH2CH2NH2, -CH2OH2CH2CH2CH2CH2CH2CH2

ch3

-ch2sch2ch2ch2nhoh, 15 -ch2sch2ch2ch2ch2nhoh,

-ch2cj2sch2ch2nhoh,

-ch2ch2sch2ch2ch2nhoh, -ch2chsch2ch2nhoh, -ch2sch2ch2no2,

20 C3H7

-ch2sch2ch2ch2no2, -ch2sch2ch2ch2ch2no2,

-CH2CH2SCH2CH2N02 and -CH2CH2SCH2CH2CH2N02. Within this class of compounds, the preferred members are those where Y is hydrogen, ethyl or a-25 hydroxyethyl, and the most preferred members contain hydrogen or a-hydroxyethyl and especially a-hydroxyethyl for Y.

A particularly preferred embodiment of the present invention consists of the following compounds of the formula:

(a) Y = H; 2-CH2OCH2CH2NH2;

(b) Y = a-hydroxyethyl; 2-CH2OCH2CH2NH2;

(c) Y = H; 2-CH2OCH2CH2NHOH;

(d) Y = a-hydroxyethyl; 2-CH2OCH2CH2NHOH; ss (e) Y = H; 2-CH2SCH2CH2NH2;

(f) Y = a-hydroxyethyl; 2-CH2SCH2CH2NH2;

(g) Y = H; 2-CH2SCH2CH2NHOH;

(h) Y = a-hydroxyethyl; 2-CH2SCH2CH2NHOH;

O

40 II

(i) Y = H; 2-CH2S CH2CH2NH2;

O

II

(j) Y = a-hydroxyethyl; 2-CH2SCH2CH2NH2;

O

II

(k) Y = H; 2-CH2S CH2CH2NHOH;

O

50 h

(1) Y = a-hydroxyethyl; 2-CH2S CH2CH2NHOH; (m) Y = H; 2-CH20CH2CH2N02; (n) Y = a-hydroxyethyl; 2-CH20CH2CH2N02; (o) Y = H; 2-CH2SCH2CH2N02;

55 (p) Y = a-hydroxyethyl; 2-CH2SCH2CH2N02;

O

II

(q) Y = H; 2-CH2S CH2CH2N02; and

O

60 H

(r) Y = a-hydroxyethyl; 2-CH2SCH2CH2N02. Particularly preferred are the compounds described above, wherein Z in formula I is hydrogen, pharmaceutically acceptable salts and physiologically cleavable esters thereof, such as acetoxymethyl, methoxymethyl, pivaloyloxymethyl, phthalidyl and indanyl esters.

Most preferred compounds of the present invention are those where Y is hydrogen or stronger

643 846

preferably represent a-hydroxyethyl and the 2-substituent -CH2OCH2CH2NH2, in particular the free acids, pharmaceutically acceptable salts thereof and physiologically cleavable esters thereof.

The invention also relates to the methods described in claims 5-8. The present invention also relates to the new compounds of the formula

II

C02E "

where Y corresponds to the definition for formula I, Q phenyl or (lower) alkyl, R "an easily removable ester protection

O

II

group and T -C-X, wherein X is - (Alk) -A- (Alk ') - R2o, as means for carrying out the processes as defined in claims 5-8.

In the intermediates of formula II, Q is preferably phenyl, R "is preferably p-nitrobenzyl and X and Y are preferably those substituents which are preferred for compounds of formula I. Reactive functional groups such as mercapto, amino and hydroxy in substituents X and Y can protected by conventional protecting groups during the conversion of the intermediates to biolo-5 gically active end products.

Compound I can be prepared by one of the reaction routes described below. The methods described also include the methods claimed in claims 10-5. However, all of the processes described below are suitable for the preparation of the compounds of the formula I according to the invention. The different synthetic routes can be divided into three main processes, which differ at the time of the introduction of 15 of the 6-substituent, i.e. Y, differentiate. In process I the 6-substituent is already contained in the starting product, process II contains the introduction of the substituent at the end of the synthesis and in process III the substituent Y is introduced in the middle of the synthesis. Each of these three main processes can in turn be subdivided depending on the time of introduction of the 2-substituent, i.e. X. In general, the introduction of the substituent Y in the middle of the synthesis is preferred and the introduction of the substituent X by acylation of the mercaptide intermediate III or IIIa proved to be the most favorable.

Process I can be represented by the following scheme:

Procedure I (Variation 1): Early introduction of the 2-substituent

Y-CH = CE-OAc

CSI

N

'OAc

H

0 II

XC-SNa pH 7.5

O ii

.SC-X

\

H

CHO I

co2R "

T

SOCI.

P0.

ßase

■ r

^ N ^^ P03

C02R "

643 846

8th

ßaHlock'verurwj

O

II

Ac = CH3C-0 = QHy-

V

1 /

C02H

Procedure I (Variation 2): Late introduction of the 2-substituent

Y-CH = CK-OAc CSI

-SAC

^ N \

0 h

N.

CHO I

CO R "

-OAc

H

O

11

CH3C-SNa pH 7.5

>

SAc

, Oïï

co2r "

soci.

-S Ac

N

Cl co2R "

p0.

base

SAc

-N.

^ P03

c02r "

MA

base

■ SM

N \ ^ 3

co2r-

o il x-c- ©

o II

.sc-x c02r "

->

9

643 846

O

0

■> -

co2K '

>

X-C- + = acylating agent MA = heavy metal salt

Procedure I (Variation 3): Late introduction of the 2-substituent

^ -OAC

y-ch = ch-oac csi

N.

0jCSNa pH 7.5

■>

H

SC0.

\

H

SC0.

n c02r "

cho I

co2r "

P0.

Cl Sase

V. • ^ SC0-

"oh co2r"

^ SC0.

SOCI.

I '^! P03

ma base a

c02r "

■ SM

r

-N ^ '^ P0.

co2R "

O II

X-C- ©

O II

.sc-x

O

co2r "

643846

10th

In process I, a vinyl ester (Y = H or a radical, defined in connection with compounds I), containing the desired 6-substituent by cycloaddition reaction with a chlorosulfonyl isocyanate (CSI) followed by reduction with an organic reducing agent such as sodium sulfite to optionally 1 -substituted-4-acetoxy-2-azetidinone converted. The CSI reaction is preferably carried out in an inert organic solvent such as diethyl ether at a temperature of 0 ° C or below. The reduction step can be carried out in an aqueous or aqueous-organic reaction mixture at a temperature of 0 ° C. or below and at a slightly basic pH.

After the formation of the 4-acetoxy-2-azetidinone, Process I can proceed in three different ways. In the first case (variation 1) the azetidinone is treated with a thiol

o ii acid X-C-SH reacted, where X corresponds to the definition from compound I, or with a salt thereof in a suitable solvent (e.g. aqueous or aqueous-organic). The removal of the acetoxy group results in the introduction of the desired 2-substituent in the azetidinone at this time. The cleavage reaction is preferably carried out at room temperature or below and at a slightly basic pH (approx. 7.5). If Y is not hydrogen, the eis and trans isomers of the resulting azetidinoris can preferably be separated (e.g. by chromatography). Variations 2 and 3 consist in the conversion of 4-acetoxy-2-azetidinonsin 4-acetyl-thio-2-azetidinone or 4-tritylthio-2-azetidinone by nuclophilic cleavage with thioacetic acid or triphenylmethyl mercaptan (or a salt like the sodium salt).

The 4-thio-azetidinone is then treated with a glyoxylate

O

II

ester HC-C02R "in which R" is an easily removable ester protecting group such as p-nitrobenzyl or trimethylsilyl-ethyl, or a reactive oxo derivative thereof such as a hydrate, in an inert organic solvent (e.g. benzene, toluene, xylene and the like) ) and preferably at an elevated temperature (for example 50 ° C. to the most preferred reflux temperature). If a hydrate of the ester is used, the resulting water can be removed azeotropically or with molecular sieves. The hydroxyester product is formed as a mixture of epimers, which can be separated by chromatography or can be used directly in the next step.

The conversion of the hydroxy ester into the corresponding chloro ester takes place by reaction with a chlorinating agent (e.g. SOCl2, POCl3, PCI5 and the like) in an inert organic solvent (e.g. tetrahydrofuran, diethyl ether, methylene chloride, dioxane and the like) in the presence or absence of a base, preferably one aliphatic tertiary amine, e.g. Triethylamine, or a heterocyclic tertiary amine (e.g. pyridine or collidine). The reaction is preferably carried out at about -10 ° C to room temperature. The chloroester product is obtained as a mixture of epimers, which can optionally be separated before further use.

The phosphorane intermediate can be obtained by reacting the chloroester with a suitable phosphine (preferably triphenylphosphine or tri (lower) alkylphosphine such as triethylphosphine or tri-n-butylphosphine) in an inert organic solvent such as dimethylformamide, dimethyl sulfoxide, tetrahydrofuran, dimethoxyethane, dioxane or an aliphatic, cycloaliphatic or aromatic

Hydrocarbon (e.g. hexane, cyclohexane, benzene, toluene and the like) can be obtained in the presence of a base, preferably an organic tertiary amine such as triethylamine, pyridine or 2,6-lutidine. The reaction is preferably carried out at a temperature from room temperature to the reflux temperature of the solvent system.

At this stage, the synthetic process again branches into two ways. In variation I (the 2-substituent has already been introduced), the intermediate phosphorane product is converted into the desired penem by thermal cyclization in an inert organic solvent at a temperature from just above room temperature to the reflux temperature of the solvent system. This cyclization is suitably carried out under reflux conditions. The suitable organic solvents are aliphatic, cycloaliphatic or aromatic hydrocarbons (e.g. benzene, toluene, hexane, cyclohexane), halogenated hydrocarbons (e.g. methylene chloride, chloroform, carbon tetrachloride), ether (diethyl ether, 20 dioxane, tetrahydrofuran, dimethoxyethane), carbide cyclic (e.g. dimethylformamide), Di-C | -C6-alkyl sulfoxide (e.g. dimethyl sulfoxide) or a C, -C6-alkanol (e.g. methanol, ethanol, t-butanol) or a mixture thereof.

In variations 2 and 3, the phosphorane is converted into a heavy metal mercaptide of the formula

30th

35

-n

p (q).

co2r "

III

M

40

or

, SHgCOOCH.

p (q)

purple

C02R "

in which Q is preferably phenyl or (lower) alk-55 yl, x 1 or 2 and M Cu (II), Pb (II) or Hg (II) if x 2 or Ag (I) if x is 1, represent. Mercaptide formation occurs by reaction of the phosphorane with a salt of Hg (II), Pb (II), Cu (II) or Ag (I) or with (methoxycarbonyl) mercury (II) acetate in a solution containing methanol. 60 solvents and in the presence of an organic or inorganic base such as aniline, pyridine, collidine, 2,6-lutidine, an alkali metal carbonate and the like. A preferred base is pyridine. The reaction can take place at room temperature or optionally with gentle cooling or heating. 65 The anion (A) of the heavy metal salt can be any anion that provides a soluble salt in the chosen solvent, e.g. N03 ", CH3COCr, BF4 ~, F", CHV, N02 ', CNO-, etc. The mercaptide intermediate is then with

11

643 846

O

II

an acylating agent which can introduce the radical X-C-, in which X represents the desired penem-2 substituent

O

II

tuenten represents. The acylating agent (X-C- ©) can

O

II

Acid XC-OH or a reactive functional derivative thereof such as an acid halide (preferably acid chloride), acid azide, acid anhydride, mixed acid anhydride, active ester, active thioester, etc. The acylation takes place in an inert solvent (e.g. a halogenated hydrocarbon such as methylene chloride or a Ether such as dioxane, tetrahydrofuran or diethyl ether) and when using an acid derivative in the presence of an acid acceptor such as a tri (lower) alkylamine (eg triethylamine) or a tertiary organic base such as pyridine, collidine or 2,6-lutidine. If the free acid is used, the acylation is carried out in the presence of a suitable condensing agent, e.g. a carbodiimide such as N, N'-dicyclohexylcarbodiimide. The acylation of the mercaptis can be carried out in a wide temperature range, but is preferably carried out at about -20 to + 25 ° C. After acylation, the resulting phosphorane is cyclized to the desired Penem ester as described.

The formation of the phosphorane via the mercaptide intermediate (variations 2 and 3) generally gave

Product of higher purity than can be obtained by the more conventional process of variation 1.

Once the carboxyl-protected penem is formed, 5 the protecting group can be removed in a conventional manner (e.g., by hydrolysis, hydrogenation, or photolysis) to give the deblocked penem. The p-nitrobenzyl ester can be split off e.g. by catalytic hydrogenation in the presence of a noble metal catalyst such as palladium or rhodium or a derivative thereof such as an oxide, hydroxide or halide, the catalyst optionally being able to be present on a carrier such as activated carbon or diatomaceous earth. A non-reducible aqueous or non-aqueous inert solvent such as water, ethanol, methanol, ethyl acetate, tetrahydrofuran, diethyl ether or dioxane is used. The hydrogenation can be carried out at atmospheric pressure or elevated pressure and is normally carried out at room temperature for 1-5 hours, depending on the choice of the solvent and the catalyst. If an equivalent part by weight of a base such as an alkali metal or alkaline earth metal hydroxide or amine is used in the hydrogenation, the product can be obtained in the form of a carboxylic acid salt. The ß-trimethylsilylethyl ester, a further useful protective group, is normally cleaved off by treatment with fluoride ions. Further ester protecting groups can be split off in a corresponding manner.

In a second main procedure (Procedure II), the procedure is as follows:

Procedure II (Variation 1): Early introduction of the 2-substituent

CE2 = CH-OAc CSI ^

N

-OAc

H

O II

XC-SNa pH 7.5

0 II

.sc-x

CHO I

CO R "

SOCI.

0 II

-SC-X

Cl

C02R "

P0.

Bas <

0 II

.SC-X

C02R "

643 846

12

JL /

co2R '

ßas <

->

>

tieJbÊxioCVUV ^;

Procedure II (Variation 2): Late introduction of the 2-substituent ch2 = ch-oac csi.

N.

-OAc

H

.SAc

AcSNa pH 7.5

cho

'^, SAc

\

H

co2R "

SOCI.

OH

co2r "

-SAc

P0.

N. _C1 base

c02r "

SAc

N ^^ P03

MA

base

c02r "

• SM

T

O

II

X-C- ©

o II

.SC-X

c02r "

■ N \ ^ P03

C02R *

13

643846

<> *

'CO2R'

Detlodää ^ feii

C02H

Procedure II (Variation 3): Late introduction of the 2-substituent

20th

CH_ = CH-OAC CSI ^

2 7 "

-N

• SC0.

'H

N.

-OAc

H

03CSNa pH 7.5

CHO I

co2R "

SC0-

SOCI.

O

^ N

.OH

CO2R "

SC0.

_C1

C02R "

P0.

Bas «

■ r

SC0-

N -_ ^ P0,

MA Base

C02R '

• SM

O II

x-c- ©

O 11

sc-x

-N

\ ^ P03

C02R "

r

-n \ j ^

: P0.

C02R "

643 846

14

base

->

->

Unblock

As can be seen, Process II is essentially the same as Process I (except that Y must be hydrogen) until the thermal cyclization that produces the 2-substituted penem. However, any 6-substituent is introduced in this reaction step by reacting the 2-penem with a suitable electrophile in an inert solvent (e.g. tetrahydrofuran, diethyl ether, dimethoxyethane and the like) and in the presence of a strong base. In this process, the 2-penem can be reacted in the form of the free acid (obtained by deblocking as described above) in the presence of about 2 equivalents of a base or, on the other hand, a suitable 2-penem ester can be reacted in the presence of about 1 equivalent of a Base can be used. Any ester that is inert to anion formation (the reaction involves anion formation with a base followed by reaction of the electrophile with the penem anion) can be used, e.g. a (lower) alkyl ester such as methyl, ethyl, n-propyl or t-butyl, phenyl, trichloroethyl, methoxymethyl, silyl such as tri-methylsilyl or t-butyldimethylsilyl ester or a similar ester . Penem esters with an activated methylene group such as p-nitrobenzyl are not suitable and if a 2-penem ester of this type is used, this must first be deblocked and either used as the free acid or converted to a suitable ester. The type of base used is not critical and the usual strong bases such as sodium hydride, phenyllithium or butyllithium are suitable. Most preferred, however, are lithium disilyl amides or lithium dialkyl amides such as lithium dicyclohexyl amide (LDCA), lithium diethyl amide, lithium dimethyl amide or lithium di-isopropyl amide (LDA). The electrophile is chosen so that the desired Y substituent is formed by reaction with the anion and it is e.g. a halogen (e.g. Br2, I2), an alkyl halide (e.g. CH3I) or a similar halide such as an aliphatic, cycloaliphatic, cycloaliphatic-aliphatic, phenyl (lower) alkyl, heterocyclic, heterocyclic thio, heterocyclic thio (lower) alkyl or a heterocyclic (lower) alkyl halide, a tosylate or mesylate

(e.g. ch3ch20s02 -o ch3, ch3ch2oso2ch3,

O- OS02 S ° 2> 0CH2CH2CH2OSO2CH3, etc.),

an epoxy (e.g.)> an episulfide (e.g. / ^ \), an aldehyde (e.g. CH3CHO, C6H5CH2CH0), a ketone (e.g.

25 ch3coch3, rj °) or an ester (e.g.

CH3CH2COOCH3 or C6H5COOCH3). Representative examples of other suitable electrophiles are the following:

30 CH2 = CH-CH2Br

D> - \

Br

35

HCHO

"Cr

55

ch3sso2ch3

60 O II

ch3cch2ci

65

0CH = CHCHO

O

II

CH3CCH = CH2

Br

1

CH3CH-CH3

0CH2Br 0CsCCH2Br

CH3SCH2C1 0OCH2C1

0- <J °

ni

15

643 846

The most preferred electrophile is acetaldehyde, which forms the hydroxyethyl 6-substituent. The introduction of the 6-substituent by this method is preferably carried out with cooling (e.g. -80 to 0 ° C) according to the general method described in Canadian Journal of Chemistry, 50 (19) 3196-3201 (1972).

After formation of the desired 2,6-penem, an existing ester protecting group can be split off, the desired deblocked product being obtained.

The third main process (Process III) corresponds to the following 5 reaction scheme:

Procedure III (Variations 1 and 2):

SC0.

n h

.SC0.

■ n

\

b

Base r

SC0.

_N

B

ocJKS

MA / Base

-SC0.

o h

"K. ^ SM

//

if

Ï

ho

V

C02R "

0

II ^ x-c- ©

\ /

'SC0.

-N.

-oh co2r "

V

soci.

-sc-x

. N.

b

Unblock

V

643846

16

, SC0.

.Cl c02r "

P03 Base y

SC0.

N \ ^ P03

V

c02rm ma / base

N

O II

-SC-X

\

H

CHO

\ ^ ° 2r "

O II

-sc-x

, oh co2rb

Nj / 50C12

sm

: p0-

co2r "

Y

O II

.sc-x n

Cl co2r "

V

O

11 ^

x-c- © o

II

.sc-x r

N- ^ P03

c02r "

V

P03

base

O II

SC-X

N \ ^? 03

c02rj

Ny y

17th

643 846

Unblock

V

-Unblock

V

B = protecting group for ring nitrogen

The 4-tritylthio-2-azetidinone from process III is formed as in process II (variation 3). The ring nitrogen of the azetidinone is then protected by a conventionally removable protecting group such as triorganosilyl (e.g. trimethylsilyl or t-butyldimethylsilyl), methoxymethyl, methoxy-ethoxymethyl, tetrahydropyranyl and the like. The introduction of the desired Y substituent in the 1-position of the azetidinone is then obtained by reacting an appropriate electrophile with the N-protected azetidinone in the presence of a strong base (reaction conditions as described in Method II). At this point in time, the process splits into two different ways, depending on when the azetidinone is unblocked.

In one way, the N-protected intermediate is deblocked in a conventional manner (e.g. by acid hydrolysis) and then via ester formation, chlorination of the hydroxy-ester, conversion of the chloroester into a phosphorane, conversion of the phosphorane into a heavy metal mercaptide,

O

II

Acylation of the mercaptide with X-C- ©, thermal cyclization of the phosphorane obtained to the 2,6-Penemester and cleavage of the carboxyl protecting group converted to the desired 2,6-Penem. The reaction conditions for these steps are as described for Process II (Variation 3).

An alternative route comprises the steps of converting the N-protected azetidinone into a heavy metal mercapto

O

II

tid, acylation of the mercaptide with the residue XC- ©, removal of the N-protecting group, conversion of the deblocked azetidinone with the glyoxylate ester, chlorination, reaction of the chloroester with the phosphine to phosphorane, cyclization of the phosphorane to the penemester and removal of the carboxyl -Protecting group, whereby the 2,6-penem is obtained. The reaction conditions for these steps are as previously described.

In the preparation of the 2-penem or 2,6-penem compounds by the process mentioned, free functional groups in substituents X or Y which do not take part in the reaction are optionally temporarily protected, 35 this being done in a conventional manner as in the case of free amino groups by acylation, tritylation or silylation, in the case of free hydroxyl groups for example by etherification or esterification, in the case of mercapto groups by etherification or esterification, in the case of mercapto groups by esterification and in the case of free carboxyl or sulfo groups, e.g. through esterification including sily-lieren. After the reaction has ended, these groups can optionally be released again, either individually or together.

It is furthermore possible in the case of compounds of the formula I to functionally modify the 45 2- and / or 2,6-substituents in the course or after the reaction has ended, using conventional methods, in order thereby to obtain the desired substituents according to the invention. For example, Carbonyl groups can be reduced to alcohol groups, unsaturated aliphatic groups can be halogenated, amino groups can be alkylated or acylated, nitro groups can be converted to hydroxyamino or amino groups, hydroxyl groups can be etherified or esterified, etc.

55 The penem compounds in the form of the free acid can be converted into corresponding pharmaceutically usable salts thereof or into easily cleavable esters thereof (in particular physiologically cleavable esters). The salts can be obtained by reacting the free acid with a stoichiometric portion of a suitable non-toxic acid or base in an inert solvent, followed by isolating the desired salt by lyophilization or precipitation. Esters (in particular physiologically cleavable esters) can be prepared in the same way as the corresponding esters of penicillins and cephalosporins. Obtained mixtures of isomers can be separated into the individual isomers in a conventional manner. Mixtures of diastereomeric isomers can e.g. by frak

643 846

18th

tional crystallization, adsorption chromatography (column or thin layer chromatography) or other suitable separation processes. Resulting racemates can be separated into their antipodes in a conventional manner, e.g. by forming a mixture of diastereomeric salts with optically active salt-forming reagents, separating the diastereomeric salts and converting the salts into the free compounds or by fractional crystallization from optically active solvents.

The free acid penem compounds of the present invention and pharmaceutically acceptable salts and physiologically cleavable esters thereof have been found to be effective broad spectrum antibacterial agents suitable for the treatment of infectious diseases in humans and animals as evidenced by grief. negative and gram-positive organisms are caused. The compounds are also valuable as food additives for animal feed and as a means of treating mastitis in cattle.

The 2-penem acids (and physiologically cleavable esters and pharmaceutically acceptable salts thereof) of the present invention (ie compounds of the general formula I, in which Y is hydrogen) have an antibacterial activity per se and can also be used as intermediates (preferably in their Carboxyl-protected form) for the production of 2,6-disubstituted penems I via anion formation and reaction with an electrophile.

The active compounds of the present invention can be formulated as pharmaceutical mixtures containing, in addition to the active component, a pharmaceutically acceptable carrier or diluent. The compounds can be administered both orally and parenterally. The pharmaceutical mixtures can be in solid form such as capsules, tablets or dragees or in liquid form such as solutions, suspensions or emulsions. In the treatment of bacterial infections in humans, the active compounds of the present invention are administered orally or parenterally in an amount of 5-200 mg / kg / day and preferably 5-20 mg / kg / day in divided dosages, e.g. administered three or four times a day. The administration takes place in dose units, containing e.g. 125, 250 or 500 mg of the active component together with a suitable physiologically acceptable carrier or diluent.

Illustrative examples of the preparation of the starting products and the end products of the present invention, in which all temperatures are given in degrees Celsius, are given below. To simplify matters, certain abbreviations are used in the examples, the meanings of which are as follows:

CSI chlorosulfonyl isocyanate pet.ether petroleum ether ìob.p. Boiling point nmr nuclear magnetic resonance h hour

Ether diethyl ether (unless stated otherwise)

15 Celite trademark of Johns-Manville

Products Corporation for Diatomaceous Earth r.t. Room temperature

PNB p-nitrobenzyl

2oSmp melting point

LAH lithium aluminum hydride n-BuLi n-butyllithium

MIBK methyl isobutyl ketone

Et C2H5-

25 Tr -C (C6H5) 3

Me CH3-

THF tetrahydrofuran

Ph phenyl

DMF dimethylformamide

3o TEA triethylamine

PNBG p-nitrobenzyl glyoxylate

THP tetrahydropyranyl

TFA trifluoroacetic acid

HMPT hexamethylphosphoric triamide

35 or HMPA LDA lithium diisopropylamide

Ac CH3CO-

Ms CH3S02-

DMAP 4-dimethylaminopyridine

40

Production of the starting products Production of 4-tritylthio-2-azetidinone intermediates

1. l- (Trimethylsilyl) -4-tritylthio-2-azetidinone

SC <p.

cf — N \

^ Si (Me)

A solution of 345 mg (1 mmol) of 4-tritylthio-2-azetidi- almost pure desired compound. 5 (ppm, CDC13): 7.32 non, 80 mg (0.5 mmol) 1,1,1,3,3,3-hexamethyldisilazane and 55 (15H, m, aromatic), 4.22 (1H, dd , H-4), 2.67 (1H, dd, 55 mg (0.5 mmol) chlorotrimethylsilane in 20 ml dichloro-J = 4.1, J = 16, H-3), 2.22 (1H, dd , J = 2.2, J = 16, H-3), 0.3 methane was brought to reflux temperature over 18 h (9H, s, CH3).

is heating. After concentration of the reaction mixture, the 2.1 - (t-butyldimethylsilyl) -4-tritylthio-2-azetidinone was obtained

Clai3> 3

19th

643 846

1.62 ml (11.6 mmol) of triethylamine was added dropwise over 5 min to a cooled (0 °) and stirred solution of 3.5 g (10.1 mmol) of 4-tritylthio-2-azetidinone and 1.68 g ( 12.7 mmol) chlor-t-butyldimethylsilane in 35 ml DMF. The reaction mixture was stirred at room temperature for 18 h, diluted with 250 ml of water and 200 ml of ether. The organic phase was washed 3 times with 50 ml of water, dried and concentrated to give 4.33 g of an oil. After recrystallization from pentane, 4.1 g (89%) of the desired compound were obtained in the form of a white solid, mp. 113-114 °. 5 (ppm, CDC13): 7.45 (15H, m, aromatic), 4.2 (1H, dd, H-4), 2.63 (1H, dd, J = 4, J = 16, H-3 ), 2.13 (1H, dd, J = 2, J = 16, H-3), 1.0 (9H, s, t-Bu), 5 0.35 (6H, s, Me). v0 = 0 1735 cm "1.

Analysis for C28H33NOSSi Calculated: C, 73.15 H, 7.24 N, 3.05 S, 6.97 Found: C, 73.27 H, 7.32 N, 2.97 S, 6.94.

3.1 -Methoxymethyl-4-tritylthio-2-azetidinone rr

J—

sctj).

'H

CK2OCH3

A solution of 1.38 g (4.0 mmol) of 4-tritylthio-2-acetidine-dinone in 10 ml of THF was added to a well-stirred suspension of 200 mg (50%, 4.1 mmol, washed with pentane) sodium hydride in Given 10 ml THF at -15 °. 12 drops of methanol were added to the mixture and this was stirred at -15 ° for 0.5 h. 0.58 g (4.6 mmol) of methoxy-methyl bromide was added and the mixture was stirred for 2 h, diluted with ether, washed with water and brine, dried and concentrated to 1.72 g of an oil. After recrystallization from pentane, a white solid (1.41 g) mp 72-76 ° ô (ppm, CDC13) was obtained: 7.3 (15H, m, aromatic), 4.4 (3H, m, NCH2Ö and H -4), 3.22 (3H, s, CH3), 2.76 (2H, m, H-3). 25 4. l- (methoxyethoxymethyl) -4-tritylthio-2-azetidinone

, SC4>.

nf

SC <p.

Cr N-

To a suspension of 322 mg (1 mmol) of tetrabutylam monium bromide and 70 mg (85%, 1.1 mmol) of potassium hydroxide in 10 ml of dichloromethane, cooled to 5 °, was added 345 mg (1 mmol) of 4-tritylthio-2 with vigorous stirring -azetidinone and 187 mg (1.5 mmol) methoxyethoxymethyl chloride. The mixture was stirred at room temperature for 2 hours, the solvent was evaporated and the residue was partitioned between water and ethyl acetate. The dried organic phase was concentrated, 415 mg of one

35 viscous oil were obtained. After purification by column chromatography on silica gel and elution with ether (5%) - dichloromethane, 206 mg (48%) of the desired compound were obtained as an oil. S (ppm, CDC13): 7.30 (15H, m, aromatic), 4.57 (2H, AB quartet, N-CH2Ö), 4.46 (1H, dd, 40 H-4), 3.50 ( 4H, s, 0CH2CH20), 3.30 (3H, s, CH3), 2.75 (2H, m, H-3).

5. l- (2'-Tetrahydropyranyl) -4-tritylthio-2-azetidinone

1.6 ml (1.6M, 2.56 mmol) of n-butyllithium was added dropwise to a solution of 863 mg (2.5 mmol) of 4-trityl-thio-2-azetidinone in THF at -78 °. After stirring for 15 minutes, 560 mg (4.7 mmol) of 2-chlorotetra-hydropyran was added and the reaction mixture was allowed to warm to room temperature over 1.5 hours. The reaction solution was diluted with ethyl acetate, washed with brine, dried and concentrated to 635 mg of an oil. Column chromatography on silica gel and elution with dichlorometane ether gave a mixture of the isomeric compounds desired, contaminated with little starting material. § (ppm, CDC13), 7.28 (15H, m, aromatic), 4.4 (H, dd, H-4), 2.9-2.2 (2H, m, H-3), 4, 1-3.2 and 2.2-0.7 (tetrahydropyranyl).

6. Preparation of 4-tritylthio-1- (p-nitrobenzyl-2'-tri-55 phenylphosphoranylidene-2'-acetate) -2 azetidinone

, SC4>.

60

N ^ 3

CO PNB 2

1- (1 'carboxy-1' hydroxymethyl) -4-tritylthio-2-azetidinone triethylamine salt

643846

20th

jrL

STr

CHO

I.

C02H

.xho 2

TEA

Mol. Sieves; THF

• STr

çj} n ^ j »oh

V

.TEA

co2H

To a solution of 3.5 g (10.15 mmol) of 4-tritylthio-2-azetidinone in 8 ml of tetrahydrofuran were added 1.42 ml (10.15 mmol) of trityhylamine and 1.02 g (10.15 mmol) of Gly- given oxyacid hydrate. The mixture was stirred at room temperature with 4 A molecular sieves * (volume of 8 ml) for 1 h and left at room temperature overnight. The cured mixture was diluted with methylene chloride and filtered, the filtrate was evaporated and the residue recrystallized from pentane to give 5.18 g (98%) of the desired compound as a white solid. M.p. 112-115 ° C. IR vmax: 3100-3600, and io 1755 cm "1. 'Hmr (CDC13) 8: 7.3 (15H, m), 4.92 and 5.10 (1H, 2s), 4.50 (1H, dd , J = 8Hz, J = 3Hz), 3.0 (1H, dd, J = 15Hz, J = 7Hz), 3.1 (6H, q, J = 7Hz), 2.70 (1H, dd, J = 15Hz, J = 3Hz), 2.0-3.5 (2H, m) and 1.21 ppm (9H, t, J = 7Hz).

15 * molecular sieves were dried at 150 ° C for 18 h. l- (r-carboxy-l'-chloromethyl) -4-tritylthio-2-azetidmon

STr

3] .TEA

co2h

+ soci.

STr

CH2C12

*> u

Y

ci co h 2

A cooled (ice bath) solution of the triethylamine salt of l- (r-carboxy-r-hydroxymethyl) -4-tritylthio-2-azetidi-non (1.04 g, 2.0 mmol) in 5 ml of methylene chloride was added dropwise under nitrogen Treated 0.16 ml (2.2 mmol) of thionyl chloride in 2 ml of methylene chloride. The solution was stirred at room temperature for 20 minutes and concentrated. The residue was diluted with benzene and filtered through Celite / activated carbon. The filtrate was evaporated in vacuo to give 870 mg (quantitative) of the desired compound as an amorphous solid. This was used in the next step without refurbishing. IRvmax: 1775cm-1. ] Hmr (CDC13) 6: 9.22 (1H, bs), 7.27 (15H, m), 5.3 and 5.2 (1H, 2d, J = 2Hz), 4.6 (1H, m) and 2.8 ppm (2H, m).

35 1 - (1 '-Carbo-p-nitrobenzyloxy-1' chloromethyl) -4-tritylthio-2-azetidinone

\ n cl co h 2

+ pnb-oh

© Ï1 ©

Me2N = CH Cl

STr chci3

in pyridine -: / thf co „pnb 2

To a chilled (ice bath) solution of 0.17 ml (2.2 mmol) DMF in 4.4 ml chloroform * was added dropwise 0.19 ml (2.2 mmol) oxalyl chloride. The mixture was stirred in ice for 5 minutes and then at room temperature for 20 minutes. The solution was then cooled in an ice bath and added dropwise with 854 mg (2 mmol) of 1- (1'-carboxy-r-chloromethyl) -4-tritylthio-2-azetidinone in 2 ml of chloroform, followed by an 1M solution of pyridine treated in tetrahydrofuran (2.2 ml, 2.2 mmol), the solution was stirred at room temperature for 30 min, cooled to 0 ° C and added dropwise with 370 mg (2.2 mmol) paranitro-benzyl alcohol in 2 ml tetrahydrofuran / chloroform (1: 1) and 0.31 ml (2.2 mmol) of triethylamine. The solution was then stirred at room temperature for 30 minutes and evaporated. The residue was diluted with benzene and filtered through Celite / activated carbon and the filtrate was evaporated in vacuo. The crude chlorester was purified on 5 g of silica gel and eluted with methylene chloride to give 790 mg (70%) of the desired compound as a beige powder. After treatment with ether, a white solid was obtained. M.p. 168-169 ° C. IR vmax: 1780,

55 1760 cm- '. 'Hmr (CDC13) 5: 8.15 (2H, d, J = 9Hz), 7.49 (2H, d, J = 9Hz), 7.3 (15H, m), 5.75 and 5.35 ( 1H, 2s), 5.3 (2H, s), 4.55 (1H, m), 2.8 (2H, m). This compound was identical to a sample prepared by reacting 4-tritylthio-2-azetidinone with p-nitrobenzylglyoxylate, followed by Behan-60 dein with thionyl chloride.

* Chloroform was kept over molecular sieves (3Â) for 18 hours before the reaction (to remove any trace of alcohol).

65 Example 1

l- (p-Nitrobenzyloxycarbonylmethyltriphenylphosphoranyl) -4- (silver mercaptidyl) -2-azetidinone

21st

643846

, SAa

P $.

y "

CO PNB

OAc

TrSH

NaOMe

STr

>, N

t / - H

90 ml of a suspension of 13.8 g (0.05 mmol) of triphen-ylmethyl mercaptan in methanol was degassed in a stream of nitrogen for 0.5 h. The mixture was cooled to 0 ° and 2.4 g (0.05 mol, 50% oil dispersion) sodium hydride was added in portions. The resulting solution was stirred for 5 minutes and 7.7 g (0.059 mol) of 4-acetoxyazetidinone in 55 ml of water was added rapidly. The precipitation of 4-triphenylmethyl-mercaptoazetidinone (2) was instantaneous. The mixture was then stirred at room temperature for 4 h, the solid was filtered off, washed with water and dissolved in methylene chloride. The methylene chloride solution was diluted with HCl,

Washed water, aqueous sodium bicarbonate solution, water and brine and dried over MgS04. 25 (89.8%, mp 146.5-147.5 ° C).

Analysis for C22H19NOS Calculated: C, 76.49 H, 5.54 N, 4.05 S, 9.28 Found: C, 76.54 H, 5.60 N, 4.00 S, 9.36.

8 (ppm, CDCI3) 7.60-7.10 (15H, m, H-trityl), 4.62 (IH, 30 bs, NH), 4.40 (IH, dd, J «- <rans = 3 , 0, = 5, H-4), 3.24 (IH, ddd, Jgem = 15, J3-4 eis = 5, J3-nh = 1.8, H-3), 2.81 (IH, ddd , Jgem = 15, J3.4 trans = 3.0, J3_NH = 1.2, H-3). vc = 0 (CHCI3) 1760, vNH 3340.

STr

.PNB

co2pnb

^> STr c02pnb

4.54 g (0.02 mol) of hydrated p-nitrobenzylglyoxylate and 6.90 g (0.02 mol) of azetidinone 2 were refluxed in benzene in a Dean-Stark apparatus with 3-molecular sieves for 24 h. 2 x 454 mg (2 mmol) glyoxylate were added, with refluxing in between for 18 h. The mixture was then diluted with ether, washed with 5% HCl, water, aqueous 5% NaHC03, water and brine. After drying over MgSO4 (12 g, quantitative) a small part of the epimeric mixture was separated on a silica gel plate (CH2C12 ether 6: 4).

Isomer A: Rf = 0.87, mp 170.5-171.5 ° C. 8 (ppm, CDC13) 8.07 (2H, d, J = 9, Hm aromatic), 7.45 (part of d,

Ho aromatic), 7.40-7.00 (15H, m, trityl), 5.25 (2H, s, 50 CH2-PNB), 4.75 (IH, s, HCO), 4.37 (IH, dd, J3_4 tra "s = 3, W = 4, H-3), 2.83 (IH, dd, Jgem = 16, J" * = 4, H-4), 2.10 (IH, dd, Jgem = 16, J «trans = 3, H-4), 1.42 (bs, OH). vc = 0 (CHCI3) 1770.1760 (shoulder), vN02 1525, v0H 3475.

55 Isomer B: Rf = 0.75, mp 152-153 ° C. 8 (ppm, CDC13) 8.13 (2H, d, J = 9, Hm aromatic), 7.47 (2H, d, J = 9, Ho aromatic), 7.40-7.00 (15H, m, Trityl), 5.30 (3H, s, CH2-PNB, HCO), 4.45 (IH, t, J = 3.5, H-4), 2.90-2.70 (2H, AB part of ABX, H-4), 1.55 (bs OH). vc = 0 (CHC13) 1767.1755 so (shoulder), vN02 1525, v0h 3500.

.STr

Hv OH

soci.

pyridine.

STr Cl cr ~ N \ ^

òo2pnb co2pnb 4

643 846

22

A cold (-15 °) solution of azetidinone 3 (12 g,

21.7 mmol) in 150 ml THF (dried over molecular sieves) was treated with 1.9 g (24.1 mmol) 1.94 ml) pyridine and dropwise with 2.86 g (24 mmol, 1.88 ml) thionyl chloride

Treated with nitrogen. The mixture was stirred for 45 min at s 5.37.533 (2s, H-C-Cl, CH2-PNB), 4.81 (IH, m, H-4),

Stirred at -15 °, the precipitate formed was filtered off 3.27-2.40 (2H, m, H-3) vc = 0 (KBr film) 1785.1770 vN02

and washed with benzene. After evaporation of the solution 1525.

a residue was obtained which was taken up in benzene and treated with activated carbon (11.7 g, 94%, crystallized from chloroform).

6 (ppm, CDC13) 8.17 (2H, d, J = 8, Hm aromatic), 7.67-7.00 (17H, m, Ho aromatic, Tr-H), 5.80 (s, HC- Cl),

u

STr

N

Cl

CO PNB 2

<|>, P

2,6-lutidine

'STr

Y

p $.

C02PNB

A solution of 11.6 g (20.2 mmol) of chlorazetidinone 4 in 100 ml of THF (distilled over LAH) was mixed with 7.86 g (30.0 mmol) of triphenylphosphine and 2.36 g (2.56 ml), 22 , 0 mmol) 2,6-lutidine treated. The mixture was refluxed for 72 h, the precipitate formed was filtered off and washed with ether. The organic solution was then washed with 2% aqueous HCl and 5% aqueous bicarbonate solution and dried over MgSO4. To

Evaporation of the solvent gave a residue which was purified on a silica gel column (200 g). The desired phosphorane was eluted with 30.40 and 50% ether benzene. (11.4 g, 70.4%, m.p. 201-202 ° C).

Analysis for QgHioN ^ SP Calculated: C, 73.57 H, 5.04 N, 3.50 S, 4.01 Found: C, 73.58 H, 4.91 N, 3.44 S, 3.87. 30 vc = o (CHCI3) 1740, v phosphorane (1620, 1610), vN021525.

. p <j>.

COOPNB

AgNO.

Pyridine

Say

CO PNB 2

1.6 g (2 mmol) of 4-tritylmercaptoazetidinone 5 were dissolved in 20 ml of CH2C12 and the solvent was heated to 55-60 °. Phosphorane 5 was dissolved in 32 ml of methanol at the same temperature at 55-60 °. Immediately after the preparation of the methanolic solution of 6, this was with a preheated (55-60 °) mixture of methanolic 0.15 M silver nitrate solution (16 ml, 1.2 eq.) And 174 mg (178 Hl, 2.2 mmol, 1.1 eq.) Treated with pyridine. The heating bath was removed, the mixture was stirred at room temperature for 2 h and at 0 ° C for 1 h. The 45 silver mercaptide 6 formed was filtered off, washed twice with cold (0 °) methanol and 3 times with ether. (1.12 g, 84.5%, m.p. 130-135 ° C dec.). vc = 0 (CHC13) 1795.1725 (shoulder), v phosphorane (1620.1605), vN02 1530.

50 Example 2

l- (p-Nitrobenzyloxycarbonylmethyltriphenylphosphoranyl) -4- (silver mercaptidyl) -2-azetidinone

■ SCOCH.

rph3

COOPNB

K2C ° 3, AgK ° 3

MeOH

N

SAg for? Ph3 COOPNB

7

6

23

643 846

A solution of 1.796 g (3.0 mmol) of phosphorane 7 in 3 ml of chloroform was diluted with 90 ml of methanol, cooled to 0 ° under a nitrogen atmosphere and successively with 0.51 g (3.0 mmol) of silver nitrate and 0.33 g ( 2.4 mmol) treated with potassium carbonate. The reaction mixture (protected from light) was stirred at 0 ° C for 15 min, then the cooling bath was removed and stirring was continued for 3 h. Then it was cooled to -10 ° C., stirred for 1 h and filtered, the silver mercaptide was washed successively with cold methanol and ether. 1.91 g, mp 138-145 ° C (dec.), 96%. IR (Nujol) cor ': 1748.1620 and

1605. An analytical sample was obtained by preparative TLC (ethyl acetate). Mp 140-145 ° C (dec.)

Analysis for CsoE ^^ OsSPAg Calculated: C, 54.31 H, 3.65 N, 4.22 S, 4.83 s Found: C, 54.11 H, 3.48 N, 3.92 S, 4, 62.

Example 3

l- (p-Nitrobenzyloxycarbonylmethyltriphenylphosphor-anyl) -4- (silver mercaptidyl) -2-azetidinone io A. Use of aniline as base

SCOCH.

N

0 ^ T = PPh

T

3rd

COOPNB

Aniline. , AgNO.

Me OH

Say

25th

A solution of 1.8 g (3.0 mmol) of phosphorane 7 in 4 ml of chloroform was diluted with 90 ml of methanol, cooled to −15 ° C. under nitrogen and successively with 0.56 g (3.3 mmol) of silver nitrate and 1 , 5 ml (16.5 mmol) of aniline treated. The reaction mixture (protected from light)

was stirred at -15 ° C for 0.5 h and then the cooling bath was removed and stirring continued for 24 h. The reaction mixture was cooled to -10 ° C and stirred for 1 h and then filtered, the silver mercaptide was washed successively with cold methanol and ether. 1.55 g. M.p. 114-115 ° C (dec.), 77.9%. IR (nujol) cm-1. Identical to the compound from Example 2.) Silver 1 - (paranitrobenzyl-2'-triphenylphosphoranylidene-2'-acetate) -2-azetidinone-4-thiolate

B. Use of 4-dimethylaminopyridine (DMAP) as base

SCOCH.

AgNO ^ / DMAP

Say

CH2C12 / CH3OH

co2pnb

CO PNB 2

A solution of 17.96 g (30 mmol) of said S-acetylphosphorane in methanol and dichloromethane (1: 2, 450 ml) was flushed with nitrogen for 5-10 min, cooled to 5 ° C. and in succession with 5.35 g (31.5 mmol) silver nitrate and 3.85 g (31.5 mmol) 4-dimethylaminopyridine. The ice bath was removed and the solution was redissolved and added dropwise to 300 ml of cold methanol with stirring. The precipitated silver salt 45 was filtered off, washed with ether and dried. 18.1 g (91%). IR (CHCI3) vmax: 1745 (C = O from β-lactam) and 1607 cm-1 (C = O from ester).

Silver l- (paranitrobenzyl-2'-triphenylphosphoranylidene-2 "-acetate) -2-azetidinone-4-thiolate refluxed vigorously for 2 h and then stirred at room temperature for 1 h. The colored reaction mixture 50 C. Using diazabicycloundecene (DBU ) As was treated with activated carbon, filtered and evaporated, the residue was base in a small amount of dichloromethane

.SAg c / ~ N

, SCOCH3

CO_PNB 2

AgNO.

DBU, MeOH

36.0 g (0.060 mol) of said S-acetylphosphorane were dissolved in 120 ml of methylene chloride. The solvent was evaporated to give an oil, which was then dissolved in 240 ml of warm (35 ° C) methanol and quickly treated with 420 ml of a methanolic solution of 10.68 g (0.0628 mol) of silver nitrate. The resulting solution (or suspension) was stirred at room temperature for 5 minutes, cooled in an ice bath and for 5 minutes with a solution of 8.96 ml (0.060 mol) of DBU in 20 ml

CO PNB 2

60 methanol added. The mixture was stirred for 5 min, the solid was filtered off, washed with cold (0 ° C.) methanol and ether and dried in vacuo. 37.0 g (94%). IR (Nujol Naill) vmax (C = O) and 1600 cm "1 (phosphorane).

65

D. Use of pyrrolidine as base silver 1 - (paranitrobenzyl-2'-triphenylphosphoranylidene-2 "acetate) -2-azetidinone-4-thiolate

643 846

24th

SCOCH.

C = PPh

L

COOPNB

Pyrrolidine--

AaNO

C = PPh "I 2 COOPNB

Filter to a cold (0 ° C) solution of 0.60 g (1.0 mmol). The solid was washed with cold MeOH

4-acetylthio-l- (paranitrobenzyl-2 "-triphenylphosphoranyli- îound dried in vacuo. 0.548 g, mp. 115 ° C, 82.4%. IR

den-2 "acetate) -2-azetidinone in 2 ml CH2C12 became 4 ml (Nujol) vmax: 1755 (C = O) and 1600 cm-1 (aromatic). MeOH, a solution of AgN03 in MeOH (0.14N , 7.86 ml,

1.1 mmol) and a solution of pyrrolidine (0.92 ml, example 4

1.1 mmol) in 2 ml of MeOH. The cooling bath was removed- Mercury (II) - (2'-triphenylphosphoranylidene-2'-acetate) -

was removed and the reaction mixture was stirred for 2 1.75 h of 2-azetidinone-4-thiolate, cooled to −10 ° C. and stirred for 0.25 h and

.N

STr c-PPh3 C02pNB

Hg (OAc)

s, 2h9

/ - «y ™

II

COOPNB

A solution of 2.4 g (3 mmol) I in 15 ml dichloromethane was obtained, which crystallized on treatment with ether, was cooled to 5 ° C. and installed with a solution of. Yield: 1.73 g (91%). M.p. 123-127 ° C. IR

0.525 g (1.65 mmol) of mercury acetate in 15 ml of methanol is 45 (CHC13) 1745 cm-1 (vc = 0 β-lactam) 1608 cm "1 (phenyl). After stirring at 5 ° C. for 2 h the solvent was evaporated and the residue redissolved in dichloromethane and washed with cold water The organic solution, after drying over MgSO4, was treated with activated carbon and evaporated to give a foam

Example 5

A. Preparation of 3- (l'-hydroxy-r-ethyl) -l-methoxy-methyl-4-tritylthio-2-azetidinone

50

a) (l'S, 3S, 4R and l'R, 3R, 4S) -isomer (isomer C) on the mixture with 2% HCl to pH 3 and 5 times with

A solution of lithium diisopropylamide was extracted in 5 ml of 60 20 ml of ethyl acetate. The combined organi-THF at -78 ° C from n-butyllithium (1.6M, 1.0 ml, see phases were washed with saline, ge-1.6 mmol) and 0.25 ml (1.84 mmol) diisopropylamine dried and evaporated to give an oil which produces. After 30 min a solution of 491 mg ches was crystallized out by treatment with ether. 440 mg, (1.42 mmol) l-methoxymethyl-4-tritylthio-2-azetidinone in 80%, mp. 188.5-189 ° C. 'Hmr (CDC13) 8: 7.3- (15H, m, aro-

6 ml of THF was added dropwise and the solution became mat), 4.37 (2H, ABq, N-CH20), 4.32 (IH, d, J = 2, H-4) while stirring for 15 min. 3.0 ml of acetaldehyde was added dropwise - 3.17 (3H, s, OCH3), 3.32-2.70 (2H, m, H-3 and H-5) and 1.12, followed by 30 ml Water after 20 min, wor- ppm (3H, d, J = 7, CH3).

25th

643 846

Analysis for C26H27NO3S Calculated: C, 72.02 H, 6.28 N, 3.23 S, 7.39 Found: C, 71.99 H, 6.02 N, 3.21 S, 7.40.

b) (l'S, 3S, 4Rund l'R, 3R, 4S) and (l'R, 3S, 4Rund l'S, 3R, 4S) (isomers C and B).

A solution of 0.482 mmol lithium diisopropylamide was prepared at -78 ° C in 3 ml dry ether from 0.191 ml butyl lithium, a 2.52M solution in hexane (0.482 mmol) and 0.067 ml (0.482 mmol) diisopropylamine. After 20 minutes, a solution of 0.171 g (0.439 mmol) (4R and 4S) of 1-methoxymethyl-4-tritylthio-2-azetidinone in a mixture of 1 ml of dry ether and 1 ml of dry THF was added dropwise and the resulting clear solution became stirred at -78 ° C for 15 min. A solution of tetrabutylammonium fluoride (0.96 ml of a 0.5M solution in THF, 0.48 mmol) was then added to form a precipitate which was pale pink in color. After 5 minutes at -78 ° C., the reaction mixture was quenched with 0.2 ml (excess) of freshly distilled acetaldehyde and stirred for a further 15 minutes. The work-up was carried out by adding to a saturated solution of ammonium chloride and extracting with 2 x 25 ml of ethyl acetate. The combined organic phases were washed with brine and dried over magnesium sulfate, whereupon the solvent was evaporated in vacuo to give 0.228 g of an oil which was chromatographed on 10 g of silica gel. Elution with a mixture of benzene and ethyl acetate (6: 4) gave 0.106 g (62% yield) of substrate and a mixture of the two isomeric alcohols, which could then be separated by chromatography on thick-layer plates (same solvent system). The alcohol with the higher Rf value (0.033 g, 17%) was identical to the above-mentioned isomer 10 (isomer C): mp. 188.5-189 ° C (ether dichloromethane). The low Rf alcohol (0.030 g, 16%) (isomer B) was obtained as an oil which was difficult to recrystallize from hexane: mp 94-95 ° C. IR (CH2C12) vmax: 3600 (OH), 1760 cm "1 (C = 0). 'Hmr (CDC13) 8: 6.9-7.5 (15H, m, 15 aromatic), 4.2 (2H, Center of ABq, J = 11.5, CH2-O-CH3), 4.28 (IH, d, J = 2.0.4-H), 3.65 (IH, broad sextet center, H-1 '), 3.3 (IH, dd, J3 4 trans = 2.5, J31 = 5.5, H3), 3.15 (3H, s, O-CH3), 1.55 (IH, broad s, OH-1 '),' 1.05 (3H, d, J = 6.5, H-2 ').

20 Analysis for C26H27N03S Calculated: C, 72.02 H, 6.28 N, 3.23 S, 7.39 Found: C, 71.77 H, 6.36 N, 3.15 S, 7.43.

B. Preparation of trans-3-acetyl-l-methoxymethyl-4-tritylthio-2-azetidinone

C <t>.

LDA

EtOAc

CH

O

M

Lithium diisopropylamide was conventionally made from 0.34 ml (2.4 mmol) of diisopropylamine and 1.1 ml of a 2.2M solution of n-butyl lithium in hexane (2.4 mmol) in 3 under nitrogen at - 78 ° C ml THF produced. A solution of 0.78 g (2 mmol) of l-methoxymethyl-4-tritylthio-2-azetidinone in 3 ml of THF was added dropwise and after stirring at -78 ° C. for 20 min, 0.53 g (6 mmol) of ethyl acetate were added added in one portion and stirring was continued at -78 ° C. for 0.75 h. Then the reaction mixture was diluted with ether and with an ammonium chloride solution, water and brine

Washed, dried and concentrated to 0.7 g of an oil. The mixture was worked up by chromatography on 20 g of silica gel and elution with increasing proportions of ether in benzene. The appropriate fractions were evaporated to give the desired product as a colorless oil 40 (0.32 g, 37%). 'Hmr (CDC13) 8: 7.7-6.8 (15H, aromatic), 4.85 (IH, d, J = 2, H-4), 4.5 (2H, s, N-CH2-0 ), 3.9 (IH, d, J = 2, H-3), 3.22 (3H, s, CH3) and 2.0 ppm (3H, s, CH3). IR vmax: 1770.1710 cm- '.

C. Preparation of trans-3-acetyl-1- (t-butyldimethylsil-45 yl) -4-tritylthio-2-azetidinone j »= ♦, (T N \ -

LDA

\

-Bu

, CH3> 2

EtOAc w

■ sc <t>.

NCH3} 2

Diisopropyllithium amide was conventionally prepared from 0.18 ml (1.24 mmol) of diisopropylamine and 0.78 ml of a 1.6M solution of n-butyllithium in hexane (1.24 mmol) in 8 ml of THF. A solution of 0.46 g (1 mmol) of l- (t-butyldimethylsilyl) -4-tritylthio-2-azetidinone in 8 ml of THF was added dropwise at -78 ° C., after which 1 ml of ethyl acetate was added in one portion after stirring for 5 minutes was added and the mixture was stirred at -78 ° C for 3 h. The mixture was then brought to pH 6 with cold hydrochloric acid (0.5N) and extracted twice with 20 ml of ethyl acetate. The combined organic phases were dried and concentrated to 0.5 g of an oil which was recrystallized from pentane. 200 mg total, 40%, mp 122-124 ° C. IR vmax: 1750, 1710cm-1. 'Hmr (CDC13) §: 8-7.1 (15H, m, aromatic), 4.83 (IH, d, J = 2, H-4), 3.38 (IH, d, J = 2, H = 3), 1.80 (3H, s, it CH3), 0.92 (9H, s, Bu and 0.3 ppm (6H, s, CH3).

D. Preparation of trans-l- (t-butyldimethylsilyl) -3-form-yl-4-tritylthio-2-azetidinone

643 846

26

s ^ 3

.N

O XSi (CH)

\ J • *

t-Bu

To a chilled (-78 ° C) solution of 0.34 ml (2.4 mmol) diisopropylamine in 5 ml tetrahydrofuran was added dropwise. Nitrogen was given a solution of 1.6 ml (2.4 mmol) of 1.5M n-BuLi. After stirring for 30 minutes, a solution of 1.0 g (2.18 mmol) of l- (t-butyl-dimethylsilyl) -4-tritylthio-2-azetidinone in 5 ml of tetrahydrofuran was added dropwise and stirring was continued for 30 minutes . 0.8 ml (9.9 mmol) of ethyl formate was added and the cooled solution was stirred for 10 min, after which the reaction mixture was washed successively with cold IN hydrochloric acid, (5 ml), 6 ml IM sodium bicarbonate, 10 ml water and brine. The organic phase was dried over MgSO4 and evaporated and recrystallized from pentane, 810 mg (76%) of the a)

s-SC * 3

J = C

\

\ i (ch3} 2 t-Bu io formates were obtained as a white solid.

132-133 ° C. IR (CHCI3) v max: 1760.1715 cm- '. 'Hmr (CDCI3) 5: 9.0 (IH, d, J = 1.25Hz), 7.30 (15H, m), 4.7 (IH, d, J = 1.5Hz) and 3.5 ppm (IH, t, J = 1.5Hz).

Comment:

15 a) Diisopropylamine was distilled over CaH and stored over KOH b) Tetrahydrofuran was distilled over LAH and stored over molecular sieves (3Â) c) Ethyl formate was stirred with K2C03 20 at room temperature and then distilled over P205 d) n-BuLi was treated with 1N hydrochloric acid titrated.

E. Preparation of l- (t-butyldimethylsilyl) -3- (l'-hydroxy-l'-ethyl) -4-tritylthio-2-azetidinone (4 isomers)

, t-Bu

(Me),

3.4 ml (1.6M, 5.44 mmol) of n-butyllithium were added over 5 minutes to a solution of 0.847 ml (6.23 mmol) of diisopropylamine in 30 ml of THF at -78 ° C. After 0.5 h, a solution of 2.0 g (4.4 mmol) of l- (t-butyldimethylsilyl) -4-tritylthio-2-azetidinone in 20 ml of THF was added, after 15 min 10 ml of acetaldehyde were added a portion was added and after a further 15 min 100 ml of water were added. The mixture was brought to pH 5-6 with dilute hydrochloric acid and extracted 3 × with 30 ml of ethyl acetate. The organic phases were washed with brine, dried and evaporated, leaving an oil which consisted of a mixture of the four isomers A, B, C and D, as could be demonstrated by tic.

Recrystallization of the oily residue in ethyl acetate-pentane gave the isomers B and C as white solids and the isomers A and D remained in the mother liquor. The four pure compounds were obtained by preparative chromatography (Waters, 500) of the solid mentioned and the mother liquors. The proportions were: A, 17%, B, 32%, C, 39%, D, 12%. In the above-mentioned reaction, the relative proportions of A, B, C and D were obtained after using the THF instead of ether and Quent's after 1 min at -78 ° C: 12,9,30,5,38,2 and 18 , 4%. In ether, when the reaction was run at 20 ° C for 2 hours before quenching, the relative proportions were: 13.4.24.6.44 and 18%. When using a molar equivalent of anhydrous magnesium bromide in the reaction mixture, the relative proportions ended: 19.2, 19.7, 30.1 and 31%.

Isomer A: This isomer has cis stereochemistry at C3-C4. It is a racemic mixture formed from the (l'S, 3R, 4R) and the (l'R, 3S, 4S) enantiomers. Compounds which were later derived from Compound A were referred to as "isomer A". They consist of an enantiomeric mixture and have the same configuration at C) ',

35 C3 and C4. Compounds derived from compound A via a reaction which results in an inversion of the configuration are referred to below as “isomer D” if the inversion takes place at Q and as “isomer C” if the inversion takes place at C3. Mp 152-153 ° C. 'Hmr "o (CDCI3) S: 8.0-6.8 (15H, m, aromatic), 4.30 (IH, d, J = 5.5, H-4), 3.78 (IH, m , H-1 '), 3.10 (IH, dd, J = 5.5, J = 10, H-3), 1.22 (3H, d, J = 6.5, CH3), 0.95 (9H, s, Bu), 0.27 (6H, 2s,

CH3).

Analysis for C30H37NO2Si 45 Calculated: C, 71.52 H, 7.40 N, 2.78 S, 6.36 Found: C, 71.28 H, 7.41 N, 2.48 S, 6.19.

Isomer B: This isomer has trans stereochemistry at C3-C4. It is a racemic mixture formed from the (l'R, 3S, 4R) and (l'S, 3R, 4S) enantiomers. Compounds with the same configuration at Ci>, C3 and C4 are called «isomer B». IR (CHC13) v max: 1745 cm-1 (C = O). Mp 158-159 ° C. 'Hmr (CDC13) 5: 7.60-7.10 (15H, m, aromatic), 4.02 (IH, d, J = 0.8, H-4), 3.32 (IH, dd, J = 3.0, J = 0.8, H-3), 3.55-3.15 (IH, m, H-1 '), 0.88 (12H, CH3 and t-Bu), 0.16 55 (6H, s, CH3).

Isomer C: This isomer has trans stereochemistry at C3-C4. It is a racemate formed from the (l'S, 3S, 4R) and (l'R, 3R, 4S) enantiomers. Compounds with the same configuration at Cj-, C3 and C4 are referred to as «isomer C» -60. Mp 134-136 ° C. 'Hmr (CDC13) S: 7.60-7.10 (15H, m, aromatic), 4.32 (IH, d, J = 1.8, H-4), 3.02 (IH, dd, J = 2.7, J = 1.8, H-3), 3.0-2.5 (IH, dq, J = 2.7, J = 6, H-l '), 1.02 (3H, d, J = 6, CH3), 0.95 (9H, s, t-Bu), 0.27 (6H, s, CH3.IR (CHCI3) vmax: 1735 cm- '(C = 0).

65 Isomer D: This isomer has cis stereochemistry at C3-C4. It is a racemate formed from the (l'R, 3R, 4R) and (l'S, 3S, 4S) enantiomers. Compounds with the same configuration at Cr, C3 and C4 are called «isomer D»

27th

643 846

draws. M.p. 171-172 ° C. ! Hmr (CDC13) 5: 7.80-6.90 (15H, m, aromatic), 4.70 (IH, d, J = 4.5, H-4), 3.02 (IH, dd, J = 4.5, J = 0.5, H-3), 2.39 (IH, dq, J = 0.5, J = 6.5, H-1 '), 1.0 (3H, d, J = 6.5, CH3), 0.97 (9H, s, t-Bu), 0.32 (6H, s, CH3).

Analysis for C30H37NO2SSi Calculated: C, 71.52 H, 7.40 N, 2.78 Found: C, 71.27 H, 7.43 N, 2.51

b)

bra

tBu

\

• Me.

yfc-Bu i

Vie

2 trans isomei s, 6.36 s, 6.31

A solution of 1.0 g (2 mmol) of trans-3-acetyl-l- (t-butyl-dimethylsilyl) -4-tritylthio-2-azetidinone in 30 ml of THF was added dropwise under nitrogen to a cooled (0 °) and stirred suspension of 0.38 g (10 mmol) of sodium borohydride in 120 ml of THF. The ice bath was removed and the mixture was stirred at room temperature for 4 hours c)

C $.

and then poured into ice-cooled HCl (IN, pH 6), stirred for 15 min and extracted 3 times with ether. The combined ether extracts were dried and concentrated to 1.04 g of an oil which was recrystallized from pentane to give the desired compound as a 70:30 mixture of the C and B isomers. M.p. 119-121 ° C, 84%.

■ or L ^ SC <J> _

t-Bu

Si (CHJ Bu

\ -F 3 2

A suspension of 4.78 g (15 mmol) of copper (I) iodide in 50 ml of ether was cooled to 0 ° C. and treated under nitrogen with a 1.9 M solution of 26 ml (50 mmol) of methyl lithium. The brown solution was stirred at 0 ° C for 10 min and then cooled to -60 ° C and added dropwise with 2.43 g (5.0 mmol) of trans-l- (t-butyldimethylsilyl) -3-formyl-4-tritylthio -2-azetidinone treated in a mixture of 10 ml of tetrahydrofuran / 40 ml of ether. After stirring for 3 h, the solution was allowed to warm to -40 ° C and carefully treated with an 1M solution of ammonium chloride. The mixture was filtered through Celite and the organic phase was washed with an 1M solution of ammonium chloride (3x5 ml) and brine and dried over sodium sulfate. After filtering

Isomer B

35 and evaporation gave the alcohol, isomer B, which was recrystallized from warm pentane and gave 1.6 g (65%). M.p. 160-161 ° C. IR (CHC13) v max: 1730 cm-1. 'Hmr (CDC13) 5: 7.32 (15H, m), 4.05 (IH, s), 3.4 (IH, d, J = 3Hz), 3.25-3.55 (IH, m) , 1.6 (IH, s), 0.9 (12H, s) and 0.1 ppm (6H,

40 S).

Comment:

a) Tetrahydrofuran and ether were distilled over LAH b) Methyl lithium was titrated with IN hydrochloric acid

45 c) Copper (I) iodide was purified by continuous extraction with anhydrous tetrahydrofuran in the Soxhlet extractor for 18 hours and then dried in vacuo over P205 for 18 hours.

d)

l ^ S C <p.

- tBu

OH

CH

V-

SCcf).

cT ~~ n-

'Si

-Me3

■ tBu

0.1 ml (0.1 mmol) of methyl magnesium iodide was added dropwise to a cooled (0 ° C.) and stirred solution of 25 mg (0.05 mmol) of trans-l- (t-butyldimethylsilyl) -3-formyl-4-tritylthio -2-azetidinone added in 2 ml of THF. The solution was stirred at 0 ° C for 1.5 h, poured onto an ammonium chloride solution, acidified with dilute HCl (IN) and extracted with ether. Drying and concentration of the organic extracts gave an oil which consisted of the starting product and a small proportion of a mixture of the two trans compounds with dominant isomer B.

F. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) -l- (t-But-yldimethylsilyl) -3- (1'-trimethylsilyloxy-1 '-ethyl) -4-tritylthio-2-azetidinone (Isomer C)

643846

28

A solution of 15 mg (0.3 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsilyl) -3- (r-hydroxy-r-ethyl) -4-trit- ylthio-2-azetidinone and 35 mg (0.30 mmol) of azidotrimethyl-silane in 6 ml of dry THF was stirred at room temperature until the starting product disappeared (15 min). Working up the reaction mixture by column chromatography (silica gel, CH2C12) gave the desired compound in the form of a white solid (128 mg, 74%).

OH

c4>.

10 mp 144-146 ° C. 'Hmr (CDC13) 5: 7.10-7.60 (15H, m, aromatic), 4.30 (IH, d, J = 1.5, H-4), 2.25-2.89 (2H , m, H-3, -1 '), 0.82-1.07 (12H, m, t-Bu, H-2'), 0.27 (6H, s, CH3), -0.10 ( 9H, s, -0-Si (CH3) 3). IR (CHCI3) vraax: 1736 cm "1 (C = 0).

G. Preparation of (l'S, 3R, 4Rund l'R, 3S, 4S) l '- (t-But-15 yldimethylsilyl) -3- (1' -methoxymethoxyäther-1 '-ethyl) -4-trit-ylthio- 2-azetidinone (isomer A)

OCH_OCH,

N \

Si (Me) 2 t-Bu n-butyllithium (approx. 12.5 ml of a 1.6M solution in hexane, 20 mmol, just enough to obtain a permanent pink color) was added dropwise to a solution of 10.1 g (20 mmol) (l'S, 3R, 4Rund l'R, 3S, 4S) l- (t-butyldimethylsilyl) -3- (l'-hydroxy-1 '-ethyl) -4-tritylthio-2-azetidinone (isomer A ) in 100 ml THF at - 78 ° C. After stirring for 15 min, a solution of bromomethoxymethyl ether (2 ml, 24 mmol) in 30 ml of THF was added dropwise. The mixture was stirred at -78 ° for 1 hour and at room temperature for 2 hours and poured into 200 ml of ammonium chloride solution. After extraction with 3 x 200 ml ethyl acetate

n

/ (Me). Si-t-Bu tat, washing with brine, drying over sodium sulfate and concentration gave the crude desired connection, which was chromatographed on silica gel and eluted with increasing proportions of ether in benzene (10.4 g, 95%). 'Hmr (CDC13) §: 7.1-7.5 (15H, m, aromatic), 4.47 (1H, d, H-4), 4.23 (2H, ABq, J = 7.0 - CH2 -0), 3.1-3.4 (2H, m, H-3 et H-l '), 3.23 (3H, s, 0-CH3), 1.37 (3H, d, J = 6 , 5, 35 CH3), 0.97 (9H, s, Bu) and 0.25 ppm (6H, 2s, CH3).

H. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butylimethylsilyl) -3- (1'-formyloxy-1 'ethyl) -4-trityIthio-2-aceti -dinone (isomer C)

^ j) CHO

A solution of 50 mg (0.1 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsilyl) -3- (l'-hydroxy-l'-ethyl) -4-tritylthio -2-azetidinone (isomer C), 100 mg (0.4 mmol) of p-bromobenzenesulfonyl chloride and 24 mg (0.2 mmol) of dimeth-ylaminopyridine in 3 ml of DMF were added at room temperature until the starting product disappeared (0.5 h) touched. Then the reaction mixture was diluted with water and extracted with ether. The organic extracts were washed with brine, dried over MgSO4 and

5o steamed. The desired compound was worked up by column chromatography. 'Hmr (CDC13) 8: 7.80 (IH, s, CHO), 7.20-7.66 (15H, m, aromatic), 3.90-4.36 (IH, m, H-l') , 4.07 (IH, d, J = 2, H-4), 3.22 (IH, broad s, H-3), 1.18 (3H, d, J = 6.5, H-2 ' ), 1.0 (9H, s, t-Bu), 0.31 (6H, s, di-CH3).

55 I. Preparation of (l'R, 3S, 4Rand 1 'S, 3R, 4S) 1' - (t-Butyl-dimethylsilyl) -3- (r-acetoxy-l'-ethyl) -4-tritylthio-2- azetidinone (isomer B)

OH

.STr

X4

V

Ac20

Pyridine

29

643 846

A solution of 13.85 g (27.5 mmol) (l'R, 3S, 4S and l'S, 3 R, 4S) 1 - (t-butyldimethylsilyl) -3- (1'-hydroxy-1 '-ethyl) - 4-trit-ylthio-2-azetidinone in 75 ml pyridine and 50 ml acetic anhydride (prepared at 0 ° C) was stirred at room temperature for 40 h. The reagents were evaporated, the last traces were removed azeotropically with toluene three times, leaving an almost white solid. The crude derivative was recrystallized from ether / petroleum ether and yielded the pure desired compound (97.5%). 'Hmr

(CDCIj) 8: 7.64-7.03 (15H, m, H aromatic), 4.60 (IH, m, J = 6, H-1 '), 3.92 (IH, d, J = 2 , H-4), 3.55 (IH, dd, J = 2, J = 6, H-3), 1.79 (3H, s, CH3CO), 0.98 (3H, d, J = 6, CH3), 0.88 (9H, s, t-butyl), 0.12 (6H, s, CH3). IR (CHC13) vmax: 1775, 5 1740 cm "'(C = 0).

J. Preparation of l- (t-butyldimethylsilyl) -3- (l'-paranotrobenzyldioxycarbonyl) -1'-ethyl) -4-tritylthio-2-azetidinone (4 isomers)

IO PNB

2, sc4>.

tBu

"Isomer C": 8.8 ml of a 1.6M solution of n-butyl-20'Hmr (CDC13) 8: 8.32-6.90 (19H, m, aromatic), 5.1 (2H, s, thium in hexane (14 mmol, immediate enough to contain benzyl), 4.65-4.20 (IH, m, H-1 '), 3.97 (IH, d, J = 1.5, H-4 ) To obtain a pink color) were added dropwise to a sol- 3.58 (IH, dd, J = 1.5, J = 5.8, H-3), 1.1 (3H, d, CH3), 0, 7 (9H, solution of "isomer C" of l- (t-butyldimethylsilyl) -3- (l'-hydr-s, Bu) and 0.2 ppm (6H, s, CH3). IR (film) vmax: 1755, oxy-l'-ethyl) -4-tritylthio-2-azetidinone (6.55 g, 13 mmol) in 1740 cm- 'C = 0.

70 ml THF given at - 78 ° C. After stirring during 25 “isomer A”: the “isomer A” of 1- (t-butyldimethylsil-15 min) was a solution of 3.2 g (14.8 mmol) of paranitro-yl) -3- (l'-hydroxy -l'-ethyl) -4-tritylthio-2-azetidinone, behan-benzyl-chloroformate in 30 ml THF added dropwise. delt as described above, gave pure "isomer A" of 1-The mixture was stirred at -78 ° C for 1 h and poured into (t-butyldimethylsilyl) -3- (l'-paranitrobenzyldioxycarbonyl-1'-100 ml of an ammonium chloride solution Extraction ethyl) -4-tritylthio-2-azetidinone in the form of an oil. 95%. with 3 x 100 ml ethyl acetate, washing with brine, 30 'Hmr (CDC13) 8: 8.3-6.7 (19H, m, aromatic), 4.95 (2H, drying and concentration gave 11 g of crude product. The pure ABq, benzyl), 4.53 (1H, p, J = 7.5, J = 7.5, H-1 '), 4.31 (1H, d, desired compound was obtained by Chromatogra- J = 6, H-4), 3.32 (IH, dd, J = 6, J = 7.5, H-3), 1.44 (3H, d, phase on 220 g silica gel and elute with increasing proportion J = 6 , 5), 0.95 (9H, s, t-Bu) and 0.2 ppm (6H, 2s, CH3).

len of ether in benzene. 93%. Mp 118-119 ° C (ether). “Isomer D”: In the same way, “isomer

'Hmr (CDC13) 8: 8.35-7 (19H, m, aromatic), 5.12 (2H, s, 35 D' of l- (t-butyldimethylsilyl) -3- (r-hydroxy-l'- ethyl) -4-benzyl), 4.08 (IH, d, J = 1.8, H-4), 4-3.5 (IH, dq, J = 6.5, tritylthio-2-azetidinone the pure “Isomer D” from l- (t-butyldi

J = 2, H-l '), 3.10 (IH, dd, J = 2, J = 1.8, H-3), 1.2 (3H, d, methylsilyl) -3- (l'- paranitrobenzyldioxycarbonyl-r-ethyl) -4-

J = 6.5, CH3), 1.0 (9H, s, Bu) and 0.30 ppm (6H, 2s, CH3). IR tritylthio-2-azetidinone, 90%. 'Hmr (CDC13) 8: 8.3-6.7 (19H, (CHC13) vmax: 1745 cm-' (C = 0). M, aromatic), 5.20 (2H, ABq, benzyl), 4, 72 (IH, d, J = 5,

Analysis for C38H42N206SiS 40 H-4), 3.50 (IH, dq, J = 6.5, J = 0.5, H-l '), 2.85 (IH, dd, J = 0.5,

Calculated: C, 66.83 H, 6.20 N, 4.10 S, 4.69 J = 5, H-3), 1.03 (3H, d, J = 6.5, CH3), 1, 0 (9H, s, t-Bu) and Found: C, 66.90 H, 6.26 N, 4, II S, 4.59. 0.35 ppm (6H, s, CH3). M.p. 130-132 ° C.

“Isomer B”: The “isomer B” of l- (t-butyldimethylsilyl) - analysis for C38H42N206S: S 3- (1'-hydroxy- l'-ethyl) -4-tritylthio-2-azetidinone, calculated - C, 66.83 H, 6.20 N, 4.10 S, 4.70 delt as described above gave pure «isomer B» of 45 found: C, 66.56 H, 6.28 N, 3.96 S, 4.89. l- (t-But- K. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-But-

yIdimethylsilyl) -3- (1 '-paranitrobenzyldioxycarbonyl-1' - yldimethylsilyl) -3- (l '-methanesulfonyloxy-1' -ethyl) -4-trityl-

ethyl) -4-tritylthio-2-azetidinone in the form of a foam, 95%. thio-2-azetidinone (isomer C)

OMs

A

r sc 4).

's \ i (ch3} 2 t-Bu

A solution of 2.0 g (4 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) 1 - (t-butyldimethylsilyl) -3- (l '-hydroxy-1' -ethyl) -4- trityl-thio-2-azetidinone (isomer C) in 80 ml dichloromethane was treated at 5 ° C. with 0.99 g (8.6 mmol) methanesulfonyl chloride and 0.87 g (8.6 mmol) triethylamine. After stirring at the same temperature for 1 h under nitrogen, the solution was washed with brine, dried over MgSO4 and concentrated to dryness. After recrystallization from ether / petroleum ether, 1.9 g (81.9%) of the desired mesylate were obtained. M.p. 120-122 ° C. 'Hmr (CDC13) 8:

60 7.13-7.61 (15H, m, aromatic), 4.50 (IH, d, J = 2, H-4), 3.62 (IH, dq, J = 6.5.2, H -l '), 2.96 (IH, dd, J = 2.2, H-3), 2.84 (3H, s, methanesulfonyl), 1.22 (3H, d, J = 6.5, H -2 '), 0.99 (9H, s, Si-t-Bu) and 0.30 ppm (6H, s, Si (CH3) 2). IR vmax (CHC13): 1746 (C = 0), 1343 and 1180 cm-1 (S02).

65 L. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) l- (t-butylimethylsilyl) -3- (l'-methanesulfonyloxy-r-ethyl) -4-trityl-thio-2 -azetidinone (isomer B)

643 846

30th

A solution of 5.03 g (10 mmol) (l'R, 3S, 4R and l'S, 3R, 4S) l- (t-butyldimethylsilyl) -3- (l'-hydroxy-r-ethyl) -4-tritylthio -2-azetidinone (isomer B), 2.52 g (22.0 mmol) of methanesulfonyl chloride and 2.23 g (22.0 mmol) of triethylamine in 200 ml of CH2C12 were stirred at 5 ° C. for 1 h. The solution was then washed with brine, dried over MgSO4 and evaporated to give a residue which crystallized as a white solid when treated with ether (5.40 g, 93%). Mp 127-131 ° C.

'Hmr (CDC13) 5: 7.20-7.63 (15H, m, aromatic), 4.51 (IH, 10 dq, J = 5.0-6.2, H-1'), 4.10 (IH, d, J = 2.0, H-4), 3.60 (IH, dd, J = 5.0-2.0, H-3), 2.03 (3H, s, -CH3) , 1.01 (3H, d, J = 6.2, H-2 '), 0.90 (9H, s, t-Bu), 0.12 (6H, s, -CH3). IR (CHC13) vmax: 1745 cm ~ '(C = 0).

M. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-p-15 bromobenzenesulfonyloxy-l'-ethyl) -l- (t-butyldimethylsilyl) -4-tritylthio-2- azetidinone (isomer C)

OSO ^ Br

A solution of 2.5 g (5 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsilyl) -3- (r-hydroxy-l'-ethyl) -4-trityl- thio-2-azetidinone (isomer C) in 100 ml of dry THF was cooled to -78 ° C. and treated with 2.38 ml (6 mmol) of 2.52M butyllithium / hexane. After 3-4 minutes, 1.53 g (6 mmol) of p-bromobenzenesulfonyl chloride, dissolved in THF, were added. The solution was stirred at -78 ° C for 3 hours and then allowed to warm to room temperature. Then the solvent was evaporated and the geoch2och3

Desired product worked up by column chromatography (silica gel, CH2C12). (3.36 g, 94.6%). Mp 142-144 ° C.

30 'Hmr (CDC13) 5: 7.68 (4H, s, benzenesulfonyl), 7.28-7.60 (15H, m, aromatic), 4.59 (IH, d, J = 1.8, H- 4), 3.68 (IH, dq, J = 6.2, H-1 '), 2.99 (IH, dd, J = 1,8,2,0, H-3), 1.18 ( 3H, d, J = 6.2, H-2 '), 1.08 (9H, s, t-Bu), 0.40 and 0.38 (6H, 2S, -CH3). IR (CHC13) v max: 1749 cm "1 (C = O).

35 N. Preparation of (l'S, 3R, 4R and l'R, 3S, 4S) 3- (l'-methoxymethyl-1 '-ethyl) -4-tritylthio-2-azetidinone (isomer A)

och2och3

A cold (0 ° C) solution of isomer A of 11 g, (20 mmol) l- (t-butyldimethylsilyl) -3- (r-methoxymethyl-l'-ethyl) -4-tritylthio-2-azetidinonine 116 ml / 13 mlHMPA / H20 was treated with 2.7 g (42 mmol) sodium azide. The cooling bath was removed and the mixture was stirred for 30 minutes and then poured into 1.3 liters of cold water and dried. The desired compound was recrystallized from ethyl acetate / hexane to give 7.2 g (83%) of a white solid. Mp 173-174 ° C. 'Hmr (CDC13) S: 7.10-7,

(15H, m, aromatic), 4.85 (2H, ABq, J = 7.4.0-CH2-0), 4.53 (IH, d, J = 5.2, H-4), 4, 42 (IH, s, NH), 4.15 (IH, m, H-1 '), 3.5 (IH, m, H-3), 3.47 (3H, s, 0-CH3), 1 , 5 (3H, d, J = 6.50 CH3).

IR (KBr) vmax: 3400-3500 (NH) and 1760 cm "'(C = O). O. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-methoxymethyloxy-1 '-ethyl) -4-tritylthio-2-azetidinone (isomer C)

55

31

643 846

A cold (dry ice / acetone bath) solution of 5.03 g (10 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsilyl) -3- (1 '-hydroxy -1'-ethyl) -4-tritylthio-2-azetidinonine 50 ml THF (distilled over LAH) was treated dropwise with a 1.6M solution of n-butyllithium in hexane (13.0 ml) until a pink color remained. 20 ml of a THF solution of 1.49 g (0.97 ml, 1.19 mmol) of bromomethyl methyl ether was added dropwise, the mixture was stirred at -78 ° C. for 30 minutes and at 0 ° C. for 3 hours. Then it was poured into an ice-cooled ammonium chloride solution and extracted with ether. The ether extracts were combined, washed with water, dried over MgS04 and evaporated to give the crude (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsilyl) -3- (r-methoxymethyloxy-r- ethyl) -4-trityl-thio-2-azetidinone (5.83 g 100%) was obtained, which was deblocked as described below.

A cold (ice bath) solution of the named derivative (5.83 g, 10 mmol) in HMPA-H20 (90 ml-10 ml) was treated with 1.365 g (21 mmol) sodium azide. The cooling bath was removed and the mixture was stirred at room temperature for 2 hours. Then it was slowly poured into 900 ml of ice-cooled water and stirred for 30 min, the precipitate formed was filtered off and dissolved in methylene chloride. The solution was then washed with water and brine and dried over MgSO4 to give 3.0 g (69.3%) of the desired compound. Mp 172-172.5 ° C (ethyl acetate-hexane). IR (CHC13) vmax: 3400 (NH) and 1760 cm "1 (C = O). 'Hmr (CDC13) S: 7.67-7.12 (15H, m, H aromatic), 4.63 (2H, Center of ■ ABq, J = 6.0-CH2-0), 4.49 (IH, s, NH), 4.40 (IH, d, J = 3, i5 H-4), 4.25-3 , 80 (IH, m, H-l '), 3.35-3.15 and 3.26 (4H, s + m, CH3 and H-3) and 1.30 ppm (3H, d, J = 6 , CH3).

P. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-formyloxy-l'-ethyl) -4-tritylthio-2-azetidinone (isomer B)

OSO 4> Br

OCHO

A solution of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-p-bromobenzenesulfonyloxy-1 '-ethyl) -1 - (t-butyldimethylsilyl) -4-tritylthio-2-azetidinone ( Isomer C) in 3 ml of DMF was heated to 50 ° C. over 48 h and then brought to 100 ° C. over 4 h. The reaction mixture was then diluted with H20 and extracted with ether. The ethereal extracts were washed with brine, dried over MgSO4 and evaporated. The desired compound was chromatographed on silica gel (5% CH3CN-QAc

.STr

NaN

CH2C12) in the form of white crystals (2 mg, 4.8%) mp 131-132 ° C. 'Hmr (CDC13) 5: 8.07 (IH, s, CHO), 30 7.24-7.56 (15H, m, aromatic), 5.23 (IH, dq, J = 6.4.7, H-1 '), 4.38 (IH, dm, J = 2.4, H-4), 4.25 (IH, s, NH), 3.20 (IH, dd, J = 7.2, 4, H-3), 1.43 (3H, d, J = 6.4, H-2 '). IR (CHC13) v max: 3400 (NH), 1765 (C = 0), 1725 cm "1 (C = O).

Q. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-Acet-35 oxy-r-ethyl) -4-tritylthio-2-azetidinone (isomer B)

OAc

'* - ■. ^

HMPT

"tBDMS

X.

oi-nh

.STr

5.77 g (10.57 mmol) of pure derivative (l'R, 3S, 4R and l'S, 3R, 4S) l- (t-butyldimethylsilyl) -3- (l'-acetoxy-r-ethyl) -4- tritylthio-2-azetidinone were dissolved in warm HMPT water (60 ml, 10 ml). The solution was cooled to room temperature and 1.2 g of NaN3 were added. Then the mixture was stirred for 45 min (the course of the reaction was monitored by tic) and slowly poured into 800 ml of stirred cold water. The mixture was then stirred for a further 20 min, the crystalline material was filtered off and washed with water. After redissolving in CH2C12, the mixture was washed twice with water and once with saline and

LDA

si (ch3) 3

ch3cho

OH

A

dried over MgS04. After evaporation of the solvent, a foam was obtained which recrystallized from ether / petroleum ether (4.90 g, 96.5%, mp. 143-144.5 ° C.). IR (CH2C12) vmax: 3395 (NH), 1772.1739 cm "1 (C = 0). 'Hmr (CDClj) 5: 7.9-6.8 (15H, m, H aromatic), 5.12 ( IH, center of dq, J = 6.5.7.5, H-19), 4.33 (IH, d, J = 2.8, H-4), 50 4.20 (IH, bs, NH ), 3.17 (IH, ddd, J3 _, - = 7.5, JM = 2.8, J3_NH = 1, H-3), 2.1 (3H, s, CH3CO), 1.35 (3H, d, J = 6.5,

CH3).

R. Preparation of 3- (l'-hydroxy-l'-ethyl) -4-tritylthio-2-azetidinone. Mixture of four isomers

OAc sc4>.

Ac O 2

Pyridine

Si-Cl

DMF -n (Et)

643 846 32

A solution of lithium diisopropylamide 1 (0.74 mmol) b: t-butyldimethylsilyl derivatives was prepared at -78 ° C in 5 ml of dry tetrahydro. 0.121 g (0.34 mmol) of the mixture of alcohols was furan from 0.103 ml (0.05 74 mmol) diisopropylamine and with 0.117 g (0.776 mmol) t-butyldimethylchlorosilane and

0.29 ml 2.52M in hexane BuLi. After 30 min at - 78 ° C 0.10 ml (7.14 mmol) triethylamine in 1 ml dry di-

a solution of 0.292 g (6.99 mmol) (R and S) 1-tris methylformamide was loaded for 36 h at room temperature

methylsilyl-4-tritylthio-2-azetidinone in 2 ml of dry tetra. After dilution with ethyl acetate, the hydrofuran solution was added dropwise. After 5 min were washed with saturated ammonium chloride solution and

0.2 ml of freshly distilled acetaldehyde was added, followed by drying over magnesium sulfate. After evaporation, after 20 min at -78 ° C., 0.716 g of an oil which had four components according to hplc

that of the starting product was determined and what the io contained.

Reaction mixture by adding to a saturated solution a = 3.7%, b = 60.6%, c = 31.1%, d = 4.6%.

was quenched by ammonium chloride. Extraction with 2 (the identity of the individual components could not be determined x 25 ml of ethyl acetate, followed by washing the combined or-) 4

ganic phases with saturated NH4C1, saline solution

and drying over magnesium sulfate gave, after evaporation: 1 butyllithium and lithium hexamethyldisilazane were a yellow oil with the solvent. Filtration of this oil ineffective on 10 g of silica gel and elution with C6H6: EtOAc, 6: 4, gave 2 with increasing polarity

0.215 g (80%) of a mixture of the alcohols. This mixture 3 acetylation of the product derived from 1-t-butyldi

('Hmr) could not be separated by either hplc or tic methylsilyl-4-tritylthio-2-azetidinone gave the following

will. 20 ratio: d = 29.5%, c = 24.1%, b = 33.8%, a = 12.6%.

a: Acetylation

The acetylation of an aliquot of the mixture 4 The reaction of a mixture of the alcohols, derived

(0.065 g) with 1.0 ml of excess acetic anhydride and of (R and S) l- (t-butyldimethylsilyl) -4-tritylthio-2-azetidi-

1.4 ml of pyridine gave a mixture of the acetates. hplc analysis non showed the following proportions: a = 5.2%,

indicated four components2: a) 34.6%, b) 17.4% c) 30.1%, 25 b = 41.3%, c = 48%, d = 4.6%.

d) 17.9%. Compound a) was identical to isomer B by S. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-

direct comparison (hplc) 4. Benzoxy-l'-ethyl) -4-tritylthio-2-azetidinone (isomer B)

OCO $

o> -N \

H

A solution of 35 mg (2 mmol) (l'S, 3S, 4R and l'R, and gave the desired compound as a white solid 3R, 4S) 3- (r-methanesulfonyloxy-r-ethyl) -4-tritylthio-2-aceti - (108 mg, 23.2%). Mp 158 ° C. 'Hmr (CDC13) 8: 7.03-8.25 dinone (isomer C) and 432 mg (3 mmol) sodium benzoate (20H, m, aromatic), 5.32 (IH, dq, J = 6.1.9, H-1 '), 4.40 (IH, 10 ml 10% H20-DMF was raised to 90 ° C for 7.5 h, 4 d, J = 2.5, H-4), 4.30 (IH , s, NH), 3.40 (IH, dd, J = 9.2.5). Then the reaction mixture was diluted with H2O H-3), 1.50 (3H, d, J = 6.1, H-2 '). IR (CHC13) vmax: 3400 (N-H), and extracted with ethyl acetate. The organic extracts 1765 (C-O), 1715 cm- '(C = 0).

were washed with brine, over MgSO4 to prepare 3- (l'-paranitrobenzyldioxycarbonyl-1'-

dries and evaporated. The residue was columnar-ethyl-4-tritylthio-2-azetidinone (4 isomers)

worked up matographically (silica gel, 5% CH3CN-CH2C12) 4S

pCO PNB

^ tBu

"Isomer C"

a) A solution of «Isomer C» of l- (t-butyldimethylsilyl) -3- (r-paranitrobenzyldioxycarbonyl-l'-ethyl) -4-trityl-thio-2-azetidinone (1.3 g) in one Mixture of 5 ml TFA,

5 ml of water, 20 ml of dichloromethane and 30 ml of methanol were stirred at room temperature for 2 days. The solution was diluted with water and the aqueous phase extracted with dichloromethane. The combined organic phases were washed with sodium bicarbonate and water, dried and concentrated to an oil. After recrystallization from ether, 902 mg of the pure desired compound were obtained. Mp 78-80 ° C. 'Hmr (CDC13) ö:

8.25-6.75 (19H, m, aromatic), 5.21 (2H, s, benzyl), 5.05

MsO

(IH, m, H-l '), 4.40 (IH, s, NH), 4.27 (IH, d, J = 2.8, H-4), 3.37 (IH, dd, J = 5.3,2.8, H-3) and 1.37 ppm (3H, d, J = 6.5, CH3). IR (CHC13) vmax: 3390 (N-H), 1765 and 1745 (shoulder) (C = O) and 1525 cm "'(N02).

b) A cold (0 ° C) solution of «isomer C» of 1 - (t-butylimethylsilyl) -3- (1'-paranitrobenzyldioxycarboxyl-1 '-ethyl) -4-tritylthio-2-azetidinone (9 , 11 g, 13.3 mmol) in 90 + 19 ml HMPT-H20 was treated with 1.82 g (27.9 mmol) sodium azide. The cooling bath was removed and the mixture 65 was stirred for 30 min and then poured into 1 liter of water and extracted 5 times with 200 ml of ether. The ether fractions were combined and washed 5 times with 200 ml of water and brine and dried over MgSO4. In

33

643 846

an alternative was the desired compound, which crystallized on dilution with water, filtered off and recrystallized from ether. 7.22 g, 89%, mp 78-80 ° C.

"Isomer B"

"Isomer B" of 3- (r-paranitrobenzyldioxycarbonyl-l'-ethyl) -4-tritylthio-2-azetidinone was prepared for isomer C as described above. 92%, mp 155.5-156 ° C (ether). Hmr (CDC13) 5: 8.25-6.80 (19H, m, aromatic), 5.20 (2H, s, benzyl), 4.95 (IH, m, H-l '), 4.35 (IH, d, J = 2.9, H-4), 4.17 (IH, s, NH), 3.20 (IH, dd, J = 10.8, J = 2.9, H-3 ) and 1.40 ppm (3H, d, J = 7.5, CH3). IR (CHC13) v max: 3480.3390 (N-H), 1772.1750 (C = 0) and 1525 cm "1 (N02).

Analysis for C32H28N206S Calculated: C, 67.59 H, 4.96 N, 4.93 S, 5.64 Found: C, 67.48 H, 4.98 N, 4.92 S, 5.67.

"Isomer A"

"Isomer A" of 3- (l'-paranitrobenzyldioxycarbonyl-l'-ethyl) -4-tritylthio-2-azetidinone was prepared for isomer C as described above. Mp 205-206 ° C. 'Hmr (CDC13) 8: 8.2-6.7 (19H, m, aromatic), 5.22 (2H, ABq, benzyl), 5.57-4.85 (IH, m, H-1') , 4.65 (IH, NH), 4.50 (IH, d, J = 6.5, H-4), 3.65 (IH, dd, J = 6.5.12, JN_H = 1, H -3) and 1.52 ppm 5 (3H, d, J = 7.5).

"Isomer D"

"Isomer D" of 3- (l'-paranitrobenzyldioxycarbonyl-r-ethyl) -4-tritylthio-2-azetidinone was prepared for isomer C as described above. 'Hmr (CDC13) 8: 8.15-6.70 (19H, m, 10 aromatic), 5.23 (2H, ABq, benzyl), 5.20 (IH, m, H-1'), 4, 75 (IH, NH), 4.52 (IH, d, J = 5.5, H-4), 3.42 (IH, J = 5.5.3, H-3) and 1.5 ppm ( 3H, d, J = 6.5, CH3). (J value for H-3 measured after exchange with D20).

15 U. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-ethanesulfonyloxy-1 '-ethyl) -4-tritylthio-2-azetidinone (isomer B)

MsO

MsO

'V' "

A solution of 4.95 g (8.5 mmol) (l'R, 3S, 4R and l'S, 3R, 4S) l- (t-butyldimethylsilyl) -3- (l'-methanesulfonyloxy-r-ethyl) -4 -tritylthio-2-azetidinone (isomer B) and 1.11 g (17.0 mmol) sodium azide in 50 ml 10% H20-HMPA was stirred at room temperature for 30 min. Then the solution was diluted with 250 ml of water and extracted with ether. The organic extracts were washed with brine, dried over MgSO4 and evaporated. After recrystallization of the residue from ether-petroleum ether, 3.33 g (83.8%) of the desired compound were obtained. M.p.

30130-131 ° C. 'Hmr (CDC13) 8: 7.20-7.62 (15H, m, aromatic), 4.97 (IH, dq, J = 6.4.6.1, H-1'), 4.56 ( IH, d, J = 2.8, H-4), 4.22 (IH, m, NH), 3.27 (1H, dd, J = 6, l, 2.8, H-3), 3 , 0 (3H, s, -CH3), 1.63 (3H, d, J = 6.4, H-2 '). IR (nujol) v max: 3195 (N-H), 1768 cm "'(C = 0).

35 V. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) -3- (l'-ethanesulfonyloxy-1 '-ethyl) -4-tritylthio-2-azetidinone (isomer C)

Oh s

^ sc (k

• U.

O Si

t-Bu

A solution of 2.85 g (4.9 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsilyl) -3- (l'-methanesulfonyloxy-r-ethyl) -4 -tritylthio-2-azetidinone (isomer C) in 25 ml of 10% aqueous HMPA was treated with 0.65 g (10 mmol) of sodium azide and stirred at 25 ° C. for 0.5 h. After dilution of the solution with 250 ml of water, the reaction product was allowed to crystallize out. The crude mesylate was redissolved in dichloromethane, washed with brine, dried over MgSO4 and evaporated. After shaking with ether, the desired compound was obtained in the form of white crystals. M.p. 155-160 ° C. 1.80 g,

78.6%. 'Hmr (CDC13) 8: 7.43 (15H, m, aromatic), 5.02 (IH, dq, J = 6.9.4.9, H-1'), 4.55 (IH, s, NH), 4.95 (IH, d, 50 J = 3, H-4), 3.33 (IH, dd, J = 4.9.3, H-3), 1.51 (3H, d, J = 6.9, H-2 '). IR vmax-. 3395 (N-H), 1768 cm "1 (C = 0).

Analysis for C25H25N04S Calculated: C, 64.22 H, 5.39 N, 3.00 Found: C, 63.93 H, 5.39 N, 3.24 55 W. Production of (l'S, 3S, 4Rund l ' R, 3R, 4S) 3- (l'-p-bromobenzenesulfonyloxy-1 '-ethyl) -4-tritylthio-2-azetidinone (isomer C)

QSO ^ Br

\ 1

OSO_éBr

643 846

34

A solution of 1.42 g (2 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-p-bromobenzenesulfonyloxy-r-ethyl) -l- (t-butyldi-methylsilyl) -4-tritylthio-2-azetidinone (isomer C) and 0.865 g (6 mmol) of sodium benzoate in 40 ml of 10% H20-HMPA was stirred at room temperature for 1 h. The solution was then diluted with 100 ml HzO and extracted with ether, whereupon the ether extracts were washed with brine, dried over MgSO4 and evaporated. The crude crystalline compound was made with a small volume

OSO ^ Br '

Shaken ether and filtered off (0.92 g, 77%). Mp 125-126 ° C. 'Hmr (CDC13) S: 7.80 (4H, s, benzenesulfonyl), 7.30-7.65 (15H, m, aromatic), 5.13 (IH, dq, J = 6.5.4.0 , H-1 '), 4.50 (IH, d, J = 2.9, H-4), 4.40 (IH, s, NH), 3.40 (IH, 5 dd, J = 4, 0.2.9, H-3), 1.50 (3H, d, J = 6.5, H-2 '). IR (CHC13) v max: 3400 cm-1 (N-H), 1770 cm "'(C = 0).

X. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-hydroxy-l'-ethyl) -4-tritylthio-2-azetidinone (isomer B)

OH

JSC *.

N.

O - ^

To a warm solution of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (rp-bromobenzenesulfonyloxy-l'-ethyl) -l- (t-butyldimethylsilyl) -4-tritylthio-2-azetidinone ( Isomer C) in 5 ml HMPA was added dropwise 1 ml H20. The reaction mixture was kept at 90 ° C. for 20 h, then diluted with ether and washed 4 × with brine. The organic solution was dried over MgSO4, concentrated

20 evaporates and the crude desired compound was worked up by column chromatography (silica gel, 15% CH3CN-CH2C12). The white solid obtained (122 mg, 44.5%) mp. 187-189 ° C was identical to a sample of the above compound, prepared by a different method.

25 Y. Preparation of 3- (l '-hydroxy-1' -ethyl) -4-tritylthio-2-azetidinone

J Nv

0 N

The two isomers (l'S, 3S, 4Rand l'R, 3R, 4S) 3- (1'-hydroxy-l'-ethyl) -4-tritylthio-2-azetidinone (isomer C) and (l'R, 3S, 4Round l'S, 3R, 4S) 3- (l'-hydroxy-l'-ethyl) -4-trityl-thio-2-azetidinone (isomer B) were prepared by the same procedure. For example, a solution of 1.0 g (2 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) l- (t-butyldimethylsil-yl) -3- (l'-hydroxy-r-ethyl) -4-tritylthio-2-azetidinone (IsomerC) and 0.865 g (6 mmol) of sodium benzoate in 40 ml of 10% H20-DMF at room temperature for 18 h. The reaction mixture was then diluted with H20 and extracted with ether, whereupon the organic extracts were washed with brine, dried over MgSO4 and evaporated. The crude desired compound was recrystallized from cold ether. (0.47 g, 61%). M.p.

134-135 ° C. 'Hmr (CDC13) 5: 7.12-7.56 (15H, m, aroma-

OCH ^ OCS ^

table), 4.48 (IH, s, NH), 4.28 (IH, d, J = 2.8, H-4), 2.94 (IH, dq, J = 6.5.6.2 , H-1 '), 3.06 (IH, dd, J = 6.2.2.8, H-3), 2.18 (IH, s, -OH), 1.30 (3H, d, J = 6.5, H-2 '). IR (CHC13) vmax: 3400 (nH), 1760 cm "'(C = O). In the same way, 40 (l'R, 3S, 4R and l'S, 3R, 4S) l- (t-butyldimethylsilyl) - 3- (l'-hydroxy-l'-ethyl) -4-tritylthio-2-azetidinone (isomer B). Mp 190-192 ° C. 'Hmr (CDC13) 5: 7.10-7.55 (15H , m, aromatic), 4.45 (IH, d, J = 2.5, H-4), 4.28 (IH, s, NH), 4.10 (IH, dq, J = 6.4, 5.3, H-1 '), 3.08 (IH, dd, J = 5.3.2.5, H-3), 1.50 45 (IH, s, -OH), 1.30 ( 3H, d, J = 6.4, H-2 '). IR (CHC13) vmax: 3400 (NH), 1760 cm-1 (C = 0).

Z. Preparation of (l'S, 3R, 4R and l'R, 3S, 4S) 3- (l'-methoxymethyl-1 '-ethyl) -1 - (paranitrobenzyl-2 "-hydr-oxy-2" -acetate) -4-tritylthio-2-azetidinone (isomer A)

50

OCH2OCH3

A mixture of 7.5 g (17.3 mmol) of 3- (l'-methoxymethyl-l'-ethyl) -4-tritylthio-2-azetidinone, 4.7 g (20.8 mmol) of paranitrobenzylglyoxylate hydrate and 300 ml of toluene were refluxed for 1 h in Dean-Stark apparatus with 3 molecular sieves. The solution was cooled in ice and 0.24 ml (1.7 mmol) of triethylamine was added dropwise. Then the mixture was stirred for 1 hour, washed with dilute hydrochloric acid, sodium bicarbonate solution and brine, dried and concentrated to give 10.5 g (94%) of the desired compound as a foam.

COOPNB

60 'Hmr (CDC13) S: 8.25-6.84 (19H, m, aromatic), 5.24 (2H, s, benzyl), 4.67-4.83 (3H, m, 0-CH2 and H-4), 4.34-4.55 (IH, m, H-2 "), 4.02 (IH, m, H-1 '), 3.54 (IH, m, H-3), 3.40 (3H, s, 0-CH3), 1.38 (3H, d, J = 6.5, CH3). IR (KBr) v max: 3360 (OH), 1770 (C = O of β-lactam ), 1735 (C = O of ester) 65 and 1605 cm "'(aromatic).

AA. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-methoxymethoxy-1 '-ethyl) -1-paranitrobenzyl-2 "-hydroxy-2" -acetate) -4-tritylthio- 2-azetidinone (isomer C)

35

643 846

och2och3

j: jX

STr cho co pnb 2

och2OCH3 J STr

"xX

OH

A solution of 1.73 g (7.11 mmol) of hydrated para-nitrobenzyl glyoxylate in 90 ml of toluene was refluxed in a Dean-Stark apparatus with 3 molecular sieves for 2 h. 3.0 g (6.93 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) 3- (r-methoxymethyloxy-l'-ethyl) -4-trit-ylthio-2- were added to the boiling solution. azetidinone and the mixture was refluxed for a further 2 h. The mixture was then cooled to room temperature, diluted with 70 mg (97 μl, 1.0.69 mmol) of triethylamine and stirred for 2 h. The reaction mixture was then diluted with ether, washed with 1% aqueous HCl, water, 1% aqueous NaHC03, water and brine, dried over MgS04 and 4.60 g (100%) of the desired

co2pnb io th compound restricted. IR (CHC13) vmax: 3530-3100 (OH), 1765.1750 (C = 0) and 1525 cm "1 (N02). 'Hmr (CDC13) 6: 8.22.8.18 (2H, 2d, J = 8, Hm aromatic), 7.67-7.0 (17H, m, H-aromatic), 5.3 (2H, bs, CH2-PNB), 5.30-5.02 (m, H-2 "), 4.89-4.52 (m, Hl 'and OH), 4.62.4.59 15 (IH, 2d, J = 2, H-4), 4.33, 4.30 (2H , 2 centriun of 2 ABq, J = 7, J = 7.0-CH2-0), 4.1-3.67 (IH, m, H-l '), 3.2 (IH, H-3) , 3.1,3.6 (3H, 2s, CH3-0) and 1.15 ppm (3H, d, J = 6.5, CH3).

BB. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-acetoxy-1 '-ethyl) -1 - (paranitrobenzyl-2 "-hydroxy-2" -acetate) -4-20 tritylthio-2-azetidinone

STr cho cot pnb

TEA

"Isomer B"

A solution of 1.82 g (30 mol) of hydrated p-nitrobenzylglyoxylate (shaken with ether) was refluxed in benzene in the Dean-Stark apparatus with 3À molecular sieves for 2 h. To this was added 10.88 g (25.2 mmol) (1'R, 3S, 4R and 1'S, 3R, 4S) 3- (1'-acetoxy-r-ethyl) -4-tritylthio-2-azetidi-non and the mixture was refluxed for another hour. The solution was then cooled to room temperature and 0.35 ml (2.5 mmol) of triethylamine was added. The mixture was then stirred for 2 h, the course of the reaction being followed by tic. * After evaporating the solvent, a white foam was obtained in quantitative yield (100%, mixture of the epimers).

co pnb 2

* In an alternative, the solution could be washed with acid and base. IR (CH3C12) vmax: 3520 (OH), 1775, 1745 cm "1 (C = O). 'Hmr (CDC13) 5: 8,2,8,18 (2H, 2d, J = 8, 35 Ho aromatic) , 7.80-6.90 (17H, m, H-aromatic), 5.28, 5.17 (2H, 24, CH2-PNB), 4.89 (0.67H, d, J = 7.2 , CHO). 4.80 (center of m, H-l '), 4.38 (0.33H, 2d, J = 8.8, CHO), 4.22 (D.33H, d, J "= 2.5, H-4), 4.09 (0.67H, d, J «= 2, 1, H-4), 3.65 (D, 67H, dd, J3_1- = 5.8, Im = »2.1, H-3), 3.47 (0.33H, dd,« J3 „r = 5.5, J3_4 = 2.5, H-3), 3.33 (0.33H, d, J = 8.8, OH), 3.23 (0.67H, d, J = 7.5, OH), 1.88.1.86 (3H, 2s, CH3CD), 1.10, 1.06 (3H, 2d, J = 5,8,6,3, CH3).

CC. Preparation of 3- (l'-paranitrobenzyldioxycarbonyl-1 '-ethyl) -1 - (paranitrobenzyl-2 "-hydroxy-2" -acetate) -4-tritylthio-45 2-azetidinone (4 isomers)

A

oco2pnb s cip.

he

N

\ h oco.pnb

2 sc ^>.

"Isomer C"

A mixture of 1.70 g (0.3 mmol) of isomer C of 3- (l'-paranitrobenzyldioxycarbonyl-1 '-ethyl) -4-tritylthio-2-azetidinone, 815 mg (3.6 mmol) of paranitrobenzylglyoxylate hydrate and 50 ml of toluene was refluxed in a Dean-Stark apparatus with 3 molecular sieves for 7 days. The cooled solution was washed with dilute hydrochloric acid solution, sodium bicarbonate solution and brine, dried and concentrated to give 2.1 g of the desired compound in the form of an epimeric mixture of carbon-2 ". Working up was carried out by chromatography on silica gel The ge

55

c02pnb desired compound can be made using a catalytic portion of triethylamine. Less polar epimer at 2 ": 'Hmr (CDC13) 8: 8.25-6.80 (23H, m, aro-60 matic), 5.30 and 3.12 (4H, 2s, benzyl), 4.65 (IH, d, 3 = 9, H-2 "), 4.45 (IH, d, J = 2.5, H-4), 4.45-4.10 (IH, m, H-l ' ), 3.50 (IH, d, J = 9.2 "-OH), 3.28 (IH, dd, J = 2.5, J = 2.5, H-3) and 1.23 ppm ( 3H, d, J = 6.5, CH3). IR (CHC13) vmax: 3530 to 3200 (DH), 1765.1750 (C = O) and 1525 cm "1 (N02). Starch-65 ker polar isomer at C-2 ": 'Hmr (CDC13) §: 8.25-6.85 (23H, m, aromatic), 5.25 and 5.08 (4H, 2s, benzyl), 5 , 05 (IH, d, J = 7, H-2 "), 4.35 (IH, d, J = 2.5, H-4), 4.40-4.05 (IH, m, H- l '), 3.42 (IH, J = 7.2 "-OH), 3.33 (IH, dd, J = 2.5.2.5,

643 846

36

H-3), 1.23 (3H, d, J = 6.5, CH3). IR (CHC13) v max: 3520 to 3200 (O-H), 1755 (C = O) and 1525 cm "1 (N02).

"Isomer B"

A mixture of 1.74 g (7.66 mmol) of hydrated paranitrobenzylglyoxylate and 3.63 g (6.38 mmol) (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l '-paranitrobenzyldioxycarbonyl-1 '-ethyl) -4-tritylthio-2-azetidinone was refluxed in 70 ml of toluene in a Dean-Stark apparatus with 3 molecular sieves for 3 h. The solution was cooled to room temperature and 64.5 mg (89 ml, 0.639 mmol) of triethylamine were added. The mixture was then stirred for 4 h, diluted with ether and washed with 2% aqueous HCl, water, 2% aqueous NaHC03, water and brine. After drying and evaporation, 5.02 g (100%) of the desired compound was obtained. The two epimers were separated by preparative chromatography on silica gel. Less polar epimer at C-2 ": IR (CHC13) vmax: 3500 (O-H), 1772.1750 (C = 0), 1525 cm" 1 (N02). 'Hmr (CDCl3) 8: 8.30-8.0 and 7.65-6.80 (23H, m, aromatic), 5.27 and 5.13 (4H, 2s, benzyl), 4.71 (IH , m, J = 6,5,6,5, H-l '), 4,28 (IH, d, J = 2,2, H-4), 4,23 (IH, d, J = 8, 7, H-2 "), 3.50 (IH, dd, J = 2.2.6.5, H-3), 3.28 (IH, d, J = 8.7, OH) and 1, 18 ppm (3H, d, J = 6.5, CH3). More polar epimer at C-2 ": IR (CHC13) vmax: 3480 (OH), 1772.1750 (C = 0) and 1525 cm-1 ( N02). 'Hmr (CDC13) 8: 8.35-6.90 (23H, m, aromatic), 5.15 (4H, benzyl), 4.72 (IH, d, J = 7.5, H-2 "0 ), 4.90-4.50 (IH,

OMs m, J = 6,5,6,5, H-1 '), 4.10 (IH, d, J = 2, H-4), 3.68 (IH, dd, J = 2.6, 5, H-3), 3.28 (1 H, d, J = 6.5, OH) and 1.15 ppm (3H, d, J = 6.5, CH3).

"Isomer A"

s The isomer A of 3- (l '-paranitrobenzyldioxycarbonyl-1' -ethyl) -4-tritylthio-2-azetidinone likewise gave a mixture of isomer A of 3- (l '-paranitrobenzyldioxycarbonyl-1' -ethyl) - l - (paranitrobenzyl-2 "-hydroxy-2" -acetate) -4-tritylthio-2-azetidinone. 'Hmr (CDC13) 8: 8.3-6.7 (23H, m, io aromatic), 5.17 (2H, benzyl), 5.0 (IH, m, H-1'), 4.9 and 4.8 (IH, 2d, J = 6, H-4.2 epimers), 4.32 and 3.96 (IH, 2s, H-2 ", 2 epimers), 3.68 (IH, dd, J = 6.6, H-3) and 1.47 ppm (3H, 2d, J = 6.5, CH3.2 epimers)

"Isomer D"

i5 The isomer D of 3- (l '-paranitrobenzyldioxycarbonyl-1' -ethyl) -4-tritylthio-2-azetidinone likewise gave a mixture of isomer D of 3- (l'-paranitrobenzyldioxycarb-onyl-l'-ethyl ) -l- (paranitrobenzyl-2 "-hydroxy-2" -acetate) -4-tritylthio-2-azetidinone. 'Hmr (CDC13) 8: 8.30-6.60 (23H, m, 20 aromatic), 5.20 (4H, m, benzyl), 4.83 (IH, 2d, J = 5, H-4) , 5.50-4.30 (2H, m, Hl 'and H-2 "), 3.48 (IH, m, H-3), 3.15 (IH, m, OH), 1.37 and 1.30 ppm (3H, 2d, CH3).

DD. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-methanesulfonyloxy-1 '-ethyl) -1 - (paranitrobenzyl-2 "-hydroxy-25 2" -acetate) -4- tritylthio-2-azetidinone (isomer C) (epimers at C2 ")

OMs

A solution of 9.72 g (42.6 mmol) of paranitrobenzylgly-oxylate hydrate in 350 ml of benzene was refluxed for 2 hours, the water being trapped azeotropically in a Dean-Stark apparatus. 16.62 g of 40 were added to the solution

(35.5 mmol) (l'S, 3S, 4Rund l'R, 3R, 4S) 3- (l'-Methanesulfon-yloxy-l'-ethyl) -4-tritylthio-2-azetidinone and it was added during a further 0 , Refluxed for 5 h. The reaction mixture was then cooled to room temperature, treated with 0.5 ml (3.5 mmol) of triethylamine and stirred for 3 h to complete the reaction. After evaporation of the solvent, a white foam was obtained, which was used as such in the next step. 'Hmr (CDC13) 8: 8.12 (2H, d, J = 9, Hm aromatic), 7.28 (17H, part of d, Ho aromatic, trityl), 5.28 (2H, s, -CH2- PNB), 4.88 (0.5H, s, Hl "), 4.62 (1.5H, m, H-2" and H-4), 4.00 (2H, m, H-l ', -OH), 3.15 (IH, m, H-3), 2.732 (3H, s, mesylate) and 1.30 ppm (3H, d, J = 6Hz, H-2 '). IR vmax: 3520 (O-H), 1775 (C = O) and 1765 cm - '(C = 0).

EE. Preparation of (l'S, 3R, 4R and l'R, 3S, 4S) 3- (l-methoxymethyl-l'-ethyl) -l- (paranitrobenzyl-2 "-chlor-2" -acetate) -4- tritylthio-2-azetidinone (isomer A)

och2och3

SC <f>.

oU

OH

V

CO_PNB 2

OCH2OCH3

COOPNB

1.1 ml (14.2 mmol) of pyridine was added dropwise to a solution of 7 g (10.9 mmol) of isomer A of 3- (l'-methoxy-methyl-l'-ethyl) -1 - (paranitrobenzyl-2 "-hydroxy -" - acetate) -4-tritylthio-2-azetidinonine 350 ml THF, cooled to -15 ° C. Immediately thereafter, 1.0 ml (14.0 mmol) of thionyl chloride was added dropwise and the mixture was stirred at -15 ° for 0.5 h. The precipitate formed was filtered off and washed with benzene, the combined filtrates were evaporated, the

60 residue dissolved in fresh benzene and the solution treated with activated carbon, filtered and concentrated to give the desired compound as an oil. 6.5 g (90%). 'Hmr (CDC13) 8: 6.65-8.35 (19H, m, aromatic), 5.24 (2H, s, benzyl), 3.43 (3H, s, OCH3) and 1.42 ppm (3H , d, J = 6.65 CH3).

FF. Preparation of (l'S, 3S, 4R and 1'R, 3R, 4S) 3- (l'-ethoxymethyloxy-l'-ethyl) -l- (paranitrobenzyl-2 "-chlor-2" -acetate) -4-tritylthio -2-azetidinone (isomer C)

37

643 846

) ch och 2 3

soci.

À

och2och3

, STr co_pnb 2

he rf

L-J ci

C02PNB

A chilled (ice-MeOH bath) solution of 4.25 g (6.62 mmol) (1 'S, 3S, 4R and 1' R, 3R, 4S) 3- (l '-Mcthoxymcth-yloxy-l' -ethyI) -l-paranitrobcnzyI-2 "-hydroxy-2" -acetate) -4-tritylthio-2-azetidinone in 60 ml of THF (distilled over LAH) was added dropwise with 0.696 ml (8.61 mmol) of pyridine and 0.530 ml (8.61 mmol) thionyl chloride treated. The mixture was stirred at -15 ° C for 30 min, the precipitate formed was filtered off and washed with benzene. The THF-benzene solution was concentrated and the residue was again dissolved in benzene. The solution obtained was treated with activated carbon, the activated carbon

10th

was filtered off on Celi te and after evaporation of the benzene, 4.86 g (100%) of the desired compound was obtained. IR (CHClj) vnnx: 1770 (C = 0) and 1525 cm "1 (N02). 'Hmr (CDC13) 5: 8.15, 8.12 (2H, 2d, H-aromatic), 7.70-7 , 00 15 (17H, m, H-aromatic), 5.62, 52.02 (IH, 2s, H-2 "), 5.27 (2H, s, CH2-PNB), 4.7 (IH, d, H-4), 4.7-3.7 (m, 0-CH2-0, H-1 '), 3.5-2.8 (m, H-3), 3.12.3, 08 (3H, 2s, 0-CH3) and 1.30-0.96 ppm (3H, m, CH3).

GG. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-20 acetoxy-1 '-ethyl) -1 - (paranitrobenzy l-2 "-chloro-2" -acc-tat) -4-tritylthio-2-azetidinone

OAc

AnToH

co pnb 2

soci.

Pyridine "

OAc

J STr

V Cl o ^ -nY "

co pnb 2

"Isomer B"

A solution of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-acetoxy-1 '-ethyl) -1 - (paranitrobenzyl-2 "-hydroxy-2" -acctate> 4 -tril-ylthio-2-azctidinone (from 10.88 g of NH) in THF (distilled over LAH) was at -15 ° C (ice / methanol bath) and under nitrogen with 2.19 g (2.24 ml , 27.7 mmol) pyridine and 3.3 g (2.02 ml, 27.7 mmol) thionyl chloride, the mixture was stirred for 20 min at -15 °, the salt was filtered off and washed with benzene Solvent (THF and benzene) was obtained a residue, which was taken up in warm benzene and oco pnb

Y

OH.

was treated with activated carbon. The suspension was filtered through Celile and a foam was obtained after evaporation of the solvent. IR (CH2C12) vniax: 1780, 1740 cm- '(C = 0). 'Hmr (CDCl3) 5: 8,17,8,21 (2H, 2d, J = 8, Ho aromatic), 7,76-6,88 (17H, m, H aromatic), 5,31, 5, 16, 5,12,4,73 (3H, 4s, CH2-PNB, CHC1), 5.12-4.55 (IH, m, 40 H-l '), 4.35-4.25 (IH, m, H-4), 3.80-3.45 (IH, m, H-3), 1.90 (3H, s, CH ^ CO), 1.12, 1.07 (3H, J = 6 , 5, CH3).

HH. 3- (1 '-Paranitrobenzyldioxycarbonyl-1' -ethyl) -1 - (pa-ranitrobenzyl-2 "-chlor-2" -acctate) -4-tritylthio ~ 2-azetidinone (mixture of epimers at C2 ")

oco2pnb

A -> * 3

J—

co pnb 2

co pnb • 2

"Isomer C"

58 mg (0.73 mmol) of pyridine were added dropwise to a solution of 470 mg (0.6 mmol), (mixture of the epimers at the C-2 ") isomer C of 3- (r-paranitrobenzyldioxycarbonyl-l'-ethyl) - 1- (paranitrobenzyl-2 "-hydroxy-2" -acetate) -3-tritylthio-2-azctidinone in 15 ml of THF, cooled to -15 ° C., were added immediately. 86.5 mg (0.73 mmol) were added immediately afterwards. Thionyl chloride was added dropwise to the mixture and this was stirred at −15 ° C. for 0.5 h, the precipitate formed was filtered off and washed with benzene, the combined filtrates were evaporated, the residue was dissolved in fresh benzene and the resulting solution was treated with activated carbon. filtered and concentrated to give the desired compound as an oil 530 rag (100%).

55 'Hmr (CDCI3) 5: 8.7-6.8 (23H, m, aromatic), 5.53 (IH, s, H-2 "), 5.30 and 5.17 (4H, 2s, benzyl ), 4.52 (IH, d, J = 2, H-4), 4.20-3.70 (IH, m, H-1 '), 3.31 (IH, dd, H-3), 1.27 and 1.21 ppm (3H, 2d, J = 6.5). IR (CHClj) vmax: 1780.1750 (C = O) and 1525 cm - '(NOz).

60 "Isomer B"

Isomer B of 3- (l-paranitrobenzyldioxycarbonyl-1'-ethyl) -l- (paranitrobenzyl-2 "-chloro-2" -acctate) -4-tritylthio-2-aceti-dinone (mixture of C-2 "- Epimcrene) was obtained in quantitative yield as described above for isomer C. 'Hmr 65 (CDC13) 5: 8.25-6.90 (23H, m, aromatic), 5.40-5.0 (4H, m, benzyl ), 5.40-4.45 (IH, m, H-1 '), 4.82 and 4.57 (IH, 2s, H-2 "), 4.36 and 4.31 (1 H, 2d , J = 2.5, H-4), 3.63 (IH, m, J = 2.5, J = 6.5, H-3), 1.25 and 1.18 ppm (3H, 2d, J = 6.5, CHj). IR

643 846

(CHClj) vmax: 1780, 1750 (C = 0) and 1525 cm "1 (N02).« Isomer A »

Isomer A of 3- (l'-paranitrobenzyldioxycarbonyl-l'-eth-yl) -l '{paranitrobenzyl-2 "-chloro-2" acetate) 4-tritylthio-2-aceti-dinone (mixture of C-2 " -Epimers). 'Hmr (CDC13) S: 8.30-6.80 (23H, m, aromatic), 5.45-4.80 (IH, m, H-l'), 5.18 and 5, 21 (4H, 2s, benzyl), 4.87 (1H, 2d, H-4), 4.22 and 3.87 (IH, 2s, H-2 "), 4.05-3.40 (1H, m, H-3), 1.57 and 1.50 ppm (3H, 2d, CH3).

"Isomer D"

Isomer D of 3- (1 "-paranitrobenzyldioxycarbonyl-1 '-eth-

OMs

38

yl) -l '{paranitrobenzyl-2 "-chloro-2" -acetate) 4-tritylthio-2-aceti-dinone (mixture of C-2 "epimers).' Hmr (CDC13) S: 8.30-6 , 70 (23H, m, aromatic), 5.32-5.10 (4H, m, benzyl), 5.48 and 5.30 (IH, 2s, H-2 "), 4.82 (IH, i.e. , J = 5, H-4), 5.30-5.20 5 (1 H, m, H-1 '), 3.15 (1 H, m, H-3), 1.40 and 1, 30 ppm (3H, 2d, J = 6.5, CH3). IR (CHCI3) vmax: 1780.1750 (C = O) and 1525 cm - '(N02).

II. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-methanesulfonyloxy-1 '-ethyl) -1 - (parani trobenzyl-2 "-chlor-2" -10 acetate) -4-tritylthio-2-azetidinone (isomer C) (epimers at C-2 ")

OMs

To a cooled (5 ° C) solution of 24.0 g (35.5 mmol) (l'S, 3S, 4Rund l'R, 3R, 4S) 3- (l'-Methanesulfonyloxy-1'-ethyl) -1- (paranitrobenzyl-2 "-hydroxy-2" -acetate) -4-tritylthio-2-azetidinone in 350 ml of dry tetrahydrofuran, 3.65 g (46.2 mmol) of pyridine and 5.5 g (36.2 mmol) of thionyl chloride were added dropwise admitted. After stirring for 45 min, 100 ml of ether were added to precipitate the hydrochloride salt and the salt formed was filtered off. The filtrate was evaporated and the residue was dissolved in 200 ml of benzene and treated with activated carbon. After evaporation of the solvent, an almost white foam was obtained, which was used as such in the next step. 'Hmr (CDC13) 5: 8.18 (2H, d, J = 9, Hm aromatic), 25 7.72 (17H, m, part of d, Ho aromatic, trityl), 5.57 and 5.12 ( IH, s, H-2 "), 5.28 (2H, s, -CH2PNB), 4.73 (IH, 2d, H-4), 3.21 (IH, 2dq, H-3), 2, 78 (3H, 2s, mesylate) and 1.21 ppm (3H, 2d, H-6H- ,, H-2 '). IR vmax: 1779 cm "' (C = O).

YY. Preparation of (l'S, 3R, 4R and l'R, 3S, 4S) 3- (l'-30 methoxymethoxy-1 '-ethyl) -1 - (paranitrobenzy l-2 "-tripheny 1-phosphoranylidene-2" acetate ) -4-tritylthio-2-azetidinone (isomer A)

OCH2OCH3

-te

OCH2OCH3

Cl

CO PNB

(/—N^^P.4,

CO PNB

A mixture of 6.6 g (10 mmol) of isomer A of 3- (l'-methoxymethoxy-l'-ethyl) -1- (paranotrobenzyl-2 "-chloro-2" acetate) -4-tritylthio-2- azetidinone, 3.3 g (12.5 mmol) of triphenyl phosphine, 1.3 ml (11 mmol) of 2,6-lutidine and 140 ml of dioxane were heated to reflux temperature for 2 days. The solution was diluted with ether, washed with dilute acid (5% HCl), water, dilute sodium bicarbonate solution and brine, dried and evaporated. The residue was chromatographed

OCH ^ OCILj

X

STr

X

Cl PNB

on silica gel and eluting with 10% ether in benzene. 45 After evaporating the appropriate fractions, the desired compound was obtained as a foam (1.4 g, 13.7%). IR (KBr) vmax: 1750 (C = 0) and 1660-1650 cm "1 (C = C, aromatic).

KK. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-50 methoxymethyloxy-1 '-ethyl) -1 - (parani trobenzyl-2 "-triphenyl-phosphoranylidene-2" -acetate) -4-tritylthio-2-azetidinone (isomer C)

och2och3

P <f>.

X

STr

X

? 4>.

PNB

A solution of 4.86 g (6.62 mmol) (1 'S, 3S, 4R and 1'R, heated and left in the heating bath (100 ° C) for 16 h. The 3R, 4S) 3- (1' - Methoxymethyloxy-1'-ethyl) -1 - (paranitrobenz mixture was diluted with ether, with 1% aqueous HCl, yl-2 "-chloro-2" acetate) -4-tritylthio-2-azelidinone in 100 ml of di- 65 water, 10% aqueous NaHC03, water and brine-oxane (distilled over LAH), containing 2.60 g (9.93 mmol) solution and washed over MgSO4. The solution triphenylphosphine and 770 mg (0.837 ml, 7.20 mmol) was evaporated and the residue through 65 g silica gel

2,6-lutidine was filtered to reflux for 4 h and eluted with 5%, 10% and 20% ether in benzene,

39

643 846

whereby 2.8 g (48%) of the desired compound were obtained. IR (CHC13) vraax: 1795 (C = O), 1620 and 1605 (Phos-phoran) and 1515 cm-1 (N02).

LL. (l'R, 3S, 4Rund l'S, 3R, 4S) 3- (l'-acetoxy-l'-ethyl) -l- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" -acetate) -4-tritylthio-2- azetidinone (isomer B)

J-

OAc

4.3?

Cl

Y

CO_PNB

2, 6-lutidine.

OAc

J STr rf

A solution of crude (1 'R, 3S, 4R and 1' S, 3R, 4S) 3- (1 '-acetoxy-1' -ethyl) -1 - (paranitrobenzyl-2 "-chlor-2" -acetate) -4-tritylthio-2-azetidinone in 100 ml of dioxane (freshly distilled over LAH) was treated with 2.97 g (3.23 ml, 27.72 mmol) of 2,6-lutidine and 9.91 g (37.8 mmol ) Treated triphenylphosphine. The mixture was refluxed in an oil bath at 130 ° C for 18 h, the solvent was then evaporated and the residue redissolved in methylene chloride. The resulting solution was sequentially diluted with HCl, H20,

Wash co2pnb diluted aqueous NaHC03, HzO and saline ge-i5. After drying and evaporation of the solvent, the desired compound was obtained as a solid, which was shaken with ether and filtered off. 14.6 g (65.9%). IR (CH2C12) vmax: 1750 (C = 0) and 1620,

1610 cm-1 (phosphorane). 2o MM. 3- (l'-ParanitrobenzyldioxycarbonyH'-ethyl) -l- (pa-ranitrobenzyl-2 "-triphenylphosphoranyliden-2" -acetate) -4-trit-ylthio-2-azetidinone oco2pnb oco2pnf co2pnb

Isomer B

A mixture of 4.96 g (6.22 mmol, mixture of the epimers at C-2 ") (l'R, 3S, 4R and l'S, 3R, 4S) 3- (l'-Paranitro-benzyldioxycarbonyl-1 '- ethyl) 1 (parani trobenzyl-2 "-chlor-2" -acetate) -4-tritylthioazetidinone (isomer B), 2.47 g (9.42 mmol) triphenylphosphine and 740 mg (0.80 mk, 6.91 mmol) 2,6-Lutidine was refluxed in dioxane (freshly distilled over LAH) for 30 hours, the solution was diluted with ether and ethyl acetate, washed with 5% aqueous HCl, water, 10% aqueous NaHC03, water and brine and dried over MgS04 Evaporation of the solvent gave a residue which was poured onto a silica gel column (10 times the weight) and eluted with 10% ether in benzene, ether and ethyl acetate. The desired compound was obtained as a crystalline solid. (3.1 g, 49%) mp 189-190 ° C (ether), IR (CHC13) vmax: 1750 (C = 0), 1620.1605 (phosphorane) and 1522 cm-1 (N02).

Isomer C

Isomer C of 3- (l '-paranitrobenzyldioxycarbonyl-1'-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -4-tritylthio-2-azetidinone was prepared for isomer B as described above. IR (CHC13) vmax: 1750 (C = 0), 1610, 1620 (phosphorane) and 1520 cm "1 (N02). 'Hmr (CDC13) 5:

8.6-6.7 (H, aromatic), 5.22 and 4.95 (benzyl), 4.70 (H-4), 35 2.6 (H-3), 1.19 and 1.07 ppm (CH3).

Isomer D

A mixture of 4.598 g (4.45 mmol, purity 77%, mixture of the epimer am C-2 ") 3- (l'-p-nitrobenzyldioxycarbon-yl-1 '-ethyl) -1 - (p-nitrobenzyl-2" - chloro-2 "acetate) -4-tritylthio-2-4o azetidinone, 1.425 g (5.44 mmol, Aldrich) triphenylphosphine and 0.63 ml (580 mg, 5.40 mmol, anachemia) 2,6-lutidine in 65 ml of dioxane (distilled over LAH) was refluxed gently under nitrogen for 41 h, the course of the reaction being monitored by tic (benzene: ether-3: 1), the dark 45 reaction mixture was cooled, diluted with EtOAc and successively with 0.1 NHC1 , Water, 2% NaHC03 and brine After drying over Na2S04 and evaporation of the solvents, 4.18 g of a dark colored oil was obtained, which was worked up by column chromatography to -50 (Si02.88 g, eluent 10-25% ether in benzene ) Yield 1.108 g (1.08 mmol, yield 24.3%) of the desired compound in the form of a yellow foam. 'Hmr (CDC13) 5: 1.08 (d, J = 6Hz, l'-CH3) .IR ( pure) vmax: 1745 cm "'(s, C = O).

55 NN. Preparation of (l'S, 3S, 4Rund l'R, 3R, 4S) 3- (l'-methanesulfonyloxy-1 '-ethyl) -1 - (paranitrobenzyl-2 "-triphenyl-phosphoranylidene-2" -acetate) -4- tritylthio-2-azetidinone (isomer C)

OMs

OMs co2pnb

643 846

40

A solution of 24.7 g (35.5 mmol) (1 'S, 3S, 4R and l'R, 3R, 4S) 3- (r-methanesulfonyloxy-l'-ethyl) -l- (paranitrobenz-yl- 2'-chloro-2 "acetate) -4-tritylthio-2-azetidinone, 11.2 g (42.7 mmol) triphenylphosphine and 4.2 g (39.1 mmol) 2,6-lutidine in 350 ml dry Dioxane was refluxed under nitrogen for 19 h, the solvent was evaporated and the crude product redissolved in ethyl acetate and washed successively with dilute HCl, NaHCO 3 and brine

Chromatograph on a silica gel column (8.5 x 12 cm). Elution with 10% ether dichloromethane (1.5 liters) and ether (1.5 liters) gave the purified phosphorane. 12.36 g (40%). 'Hmr (CDC13) 6: 2.53 and 2.93 ppm (3H, 2s, Mesy-5 lat). IR vmax: 1749 and 1620 cm "'(C = 0).

OO. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) 3- (1 '-hydroxy-1' -ethyl) -1 - (parani trobenzyl-2 "-triphenylphos-phoranylidene-2" -actate) -4-tritylthio-2-azetidinone (isomer B)

OAc

STr

^ "T ~ f

NaOH

co2pnb

. A solution of 4.43 g (5.00 mmol) of phosphorane (1 'R, 3S, 4R and l'S, 3R, 4S) 3- (r-acetoxy-l'-ethyl) -l- (paranitro-benzyl-2 " -triphenylphosphoranyliden-2 "acetate) -4-tritylthio-azetidinone in 10 ml of methanol and 60 ml of THF was treated with an eq. Treated 1% aqueous NaOH (200 mg in 20 ml H20). The course of the reaction was followed by tic *. The mixture was diluted with ether-ethyl acetate, washed with HCl, H20, aqueous NaHC03, H20 and brine. After evaporation of the solvent, a residue was obtained, which consists of

OCH2OCH3

coopnb zo benzene ether was recrystallized. (3.7 g, 87.7%) mp 169.5-170.5 ° C. IR (CH2C12) vmax: 1745 (C = 0) and

2- 1620 cm "1 (phosphorane).

* Heating the mixture increased the reaction rate.

25 pp. Preparation of (l'S, 3R, 4R and l'R, 3S, 4S) silver 3- (1 '-methoxymethyl-1' -ethyl) -1 - (paranitrobenzyl-2 "-triphenyl-phosphoranylidene-2" -acetate) -2-azetidinone-4-thiolate (isomer A)

och-7 och

> -pV

co2pnb

Silber-3- (r-methoxymethyl-l'-ethyl) -l- (paranitrobenzyl- QQ. Preparation of (l'S, 3S, 4R and l'R, 3R, 4S) Silber-2 "-triphenyl-phosphoranyliden-2" -acetate) -3-tritylthio-2-azeti- 40 2- (1 '-methoxymethyloxy-1' -ethyl) -1 - (paranitrobenzyl-2 "-tri-dinone (isomer A) was, as for isomer C of paranitrobenz- phenylphosphoranylidene-2 "acetate) -2-azetidinone-4-thiolate yldioxy-carbonyl derivative described. Yield (isomer C)

50%. IR (neat) vmax: 1745 cm "1 (C = O).

och2och3

och2och3

STr

O V3

AgNO.

co2pnb

887 mg (1.0 mmol) (l'S, 3S, 4R and l'R, 3R, 4S) 3- (l'-methoxymethyloxy-1 '-ethyl) - l- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -4-tritylthio-2-azetidinone were dissolved in 30 ml of hot (40 ° C.) methanol, with 103 mg (0.105 ml, 1.3 mmol) of pyridine and after cooling with 8.7 ml (1.3 mmol ) treated with a 0.15M solution of silver nitrate in methanol. The mixture was stirred at 23 ° C. for 1 h, cooled in an ice bath and further stirred for 20 min.

oco2pnb co pnb 2

stirs. The salt was filtered and washed successively with cold 55 methanol and ether (3 times, 671 mg, 87%). IR (CHCI3) vmax: 1745 (C = 0), 1605 (phosphorane) and 1520 cm- '(N02).

RR. Preparation of silver 3- (l'-paranitrobenzyldioxycarbonyl-1 '-ethyl) -1 - (paranitrobenzyl-2 "-triphenylphosphor-60anylidene-2" acetate) -2-azetidinone-4-thiolate

41 643 846

"Isomer B" "Isomer D"

1.02 g, (1 mmol) (l'R, 3S, 4R and l'S, 3R, 4S) 3- (1'-Para- A solution of 145 mg (0.142 mmol) of isomer D of nitrobenzylcarbonyldioxy-I'-ethyl) -l- (parani trobenzyl-2 "-tri- 3- (l'-p-nitrobenzylcarbonyldioxy-r-ethyl) -l- (p-nitrobenzyl-phenylphosphoranylidene-2" acetate) -4-tritylthio-2-azetidinone 2 "-triphenylphophanylidene-2" acetate) -4-tritylthio-2-aceti-were dissolved in 3 ml of CH2C12 and diluted with 20 ml of hot (55 ° C.) dinone by dissolving in 5 ml of CH2C12, evaporating the MeOH. The hot solution was prepared with 120 ml of CH2C12 at 55-60 ° and 4 ml of hot MeOH.

(117 mg, 1.48 mmol) pyridine and 8 ml (1.2 mmol) one of them. To the solution was treated a hot solution of AgN03 sen (55 ° C) 0.15M methanolic solution of silver nitrate in MeOH (0.15M, 1.14 ml, 0.17 mmol, 1.2 eq.) Followed by. The mixture was added at room temperature while pyridine (14 p.1.0.17 mmol, 1.2 eq.). The silver mixture was stirred for 15 minutes and then at 0 ° C. for a further 2 hours, captid began to be eliminated immediately, and the mixture was stirred. Then, on a rotary evaporator, one was evaporated for 2 h at room temperature and for 1 h 10% solution, the mercaptid was filtered off at 0 ° C., the mercaptid was filtered off and filtered with ice and twice with cold (- 15 ° C) Washed methanol and three-cooled MeOH and ether, being washed 99 mg times with ether. (917 mg, 100%). IR (Nujol Mull) (0.11 mmol, 78%) of the desired compound in the form of ei-vmax: 1745 (C = 0), 1600 (phosphorane) and 1517 cm-1 (N02). 5 nes brown solid were obtained. IR (Nujol) vmax:

"Isomer C" 1750 cm-1 (s, C = O).

Silver-3- (1 '-paranitrobenzyldioxycarbonyl-1' -ethyl) -1 - (pa-ranitrobenzyl-2 "-triphenylphosphoranyliden-2" -triphenylphos- SS. Preparation of (l'R, 3S, 4R and l'S, 3R, 4S) Silver-3-phoranylidene-2 "-acetate) -2-azetidinone-4-thiolate" Isomer C "(1'-hydroxy-1 '-ethyl) -1 - (parani trobenzyl-2" -triphenylphos-was like prepared above for isomer B. IR (Nu-20 phoranylidene-2 "acetate) -2-azetidinone-4-thiolate (isomer B) jol) vmax: 1745 (C = 0) and 1600 cm-1 (phosphorane).

X

OH OH

r STr j .SAg

AgNO ^ 1

»^ 3 W * * J-V

"Y- 3 5 5 0 ^ 3

CO PNB 'CO PNB

2 2

A solution * of 1 g (1.19 mmol) (l'R, 3S, 4R and l'S, Example 6

3R, 4S) 3- (r-hydroxy-r-ethyl) -l- (paranitrobenzyl-2 "-triphen- (l'R, 5R, 6S and l'S, 5S, 6R) 6- (l'-hydroxyethyl) - 2- (2-ylphosphoranylidene-2 "-acetate) -4-tritylthio-2-azetidinone in 35 aminoethoxymethyl) -penem-3-carboxylic acid (isomer B) 10 ml of MeOH was mixed with 124 | xl (121.3 mg, 1, 53 mmol) pyri- _

din and at 10 ° C with 15 ml (2.25 mmol - or until none white ^

excretion of silver mercaptide occurred more) ^ 5

0.15M solution of silver nitrate in MeOH treated. The ** I | \

Mix was stirred for 1 h and on the Rotationsver-40 I ^ ~ ^ H2 ° CH2 ^ H2NH2

Steamer (no bath) concentrated to about 10% concentration. The ^

Solvent was filtered off, the filter cake was washed with CO H

Washed MeOH and washed 3 times with ether and in the 2nd

High vacuum evaporated. (954 mg, 100%). IR (Nujolmuli)

vm; ix: 3500-3400 (OH), 1752 (C = 0), 1595 (phosphorane) and 45 (l'R, 3S, 4Rund l'S, 3R, 4S) 4- (2-azidoethoxy) -acetyl-1525 cm "1 (NO 2). Thio-3- (l'-hydroxyethyl) -l- (p-nitrobenzyl-2" -triphenylphos-

* The crystalline material was first dissolved in CH2C12. phoranylidene-2 "acetate) -2-azetidinone (isomer B)

OH

SAg tC »

2nd

3rd

PNB

Me3SiCl / Et3N Xm / THF! 5

OSiMe ^ X / SSiMe.

C02PNB

\

Cl

3 / Pyr

2)

TFA

/

OH

A-rYSV ^

r-y—

, N,

^ 3 C02PNB

643 846

42

To a stirred solution of 820 mg (1.16 mmol) (l'R, 3S, 4R and l'S, 3R, 4S) silver 3- (l'-hydroxyethyl) -lp-nitro-benzyl-2 "-triphenylphosphoranylidene-2 "acetate) -2-azetidinone 4-thiolate (isomer B) in 20 ml of THF were successively 0.1648 ml (4.66 mmol, 4.02 eq.) at -15 ° (MeOH ice bath) under nitrogen. Triethylamine, 0.589 ml (4.64 mmol, 4.00 eq.) Trimethylsilane and 81.2 mg (1.12 mmol) imidazole. The mixture was stirred at room temperature for 18 h (overnight) and then cooled to -10 to -15 °. Then 0.220 ml (2.72 mmol) of pyridine was added and then a solution of 372 mg (2.27 mmol, 1.96 eq.) Of 2-azidoethoxyacetyl chloride in 20 ml of CH2C12. The mixture was then stirred at room temperature for 1 h, after which the precipitate was filtered off, the filtrate was diluted with EtOAc and washed successively with 1N HCl, brine, saturated NaHC03 and brine and dried over Na2S04 and evaporated to give 748 mg of an oil. This oil was dissolved in 20 ml CH2C12 (with 3 drops of water) and stirred with 2 drops of trifluoroacetic acid at room temperature for 30 min. The mixture was then washed with saturated NaHCO 3 and brine, dried over Na 2 SO 4 and evaporated to give 695 mg of a crude oil. This oil was worked up by column chromatography (SiO 2 15 g, eluent EtOAc: CH 2 Cl 2 = 1: 1), whereby 538 mg (0.739 mmol, yield 63.7%) of the desired compound were obtained in the form of a yellow oil. 'Hmr (CDC13) 5: 1.22 (d, J = 6Hz, CH3-1'), 5.6 (2d, H-4) and 7.3 = 8.4 ppm (aromatic Hs). IR (neat) vmax: 3420 (OH), 2100 (-N3), 1750 (C = O) and 1690 cm- '(thioester). Rf 0.20 (CH2Cl2: EtOAc = 1: 1). (l'R, 5R, 6S and l'S, 5S, 6R) p-nitrobenzyl-6- (l'-hydr-15 oxyethyl) -2- (2-azidoethoxymethyl) -penem-3-carboxylate (isomer B)

CO PNB 2

toluoì .---

: h2och2ch2n3

c02pnb

A solution of 490 mg (0.673 mmol) (1 'R, 3S, 4R and rS, 3R, 4S) 4- (2-azidoethoxy) acetylthio-3- (l'-hydroxyethyl) -l- (p-nitrobenzyl- 2 "-triphenylphosphoranyidene-2" acetate) -2-azetidinone (isomer B) in 80 ml of toluene was refluxed gently for 3 h. After evaporation of the solvent in vacuo, an oily residue was obtained, which was worked up by column chromatography (Si02.10 g, eluent 5-10% EtOAc in CH2C12), whereupon it was crystallized from CH2C12 ether, whereby 202 mg (0.449 mmol, yield 66 , 8%) of the desired compound were obtained in the form of pale yellow crystals. 'Hmr (CDC13) 5: 1.35 (3H, d, J = 6.5Hz, CH3-1'), 2.18 (IH, br, OH), 3.2-3.9 (5H, m, -CH2- and H-6), 3.9-4.5 (IH, m, H-l '), 4.45-4.72-4.75-5.02 (2H,

Oh

AB type, CH2-2), 5.02-5.25-5.35-5.57 (2H, AB type, 35 -CH2Ar), 5.62 (IH, d, J = 1Hz, H- 5) and 7.42-7.65-8.13-8.28 ppm (4H, A2'B2 ', aromatic Hs). IR (Nujol) vmax: 3460 (-OH), 2110 (-N3), 1765 (β-lactam) and 1680 cm- '(ester). An analytical sample was obtained by further recrystallization. Mp 107-108 ° C (CH2C12 ether) UV (EtOH) 40 K-.m- 264 (s 12000) and 323 mu (s 9200). Rf 962 (CH2Cl2: EtOAc = 1: 1).

Analysis for QgH ^ NsOyS Calculated: C, 48.10, H, 4.26, N, 15.88, S, 7.13 Found: C, 47.81 H, 4.18 N, 15.00 S, 7 , 16th 45 (1 'R, 5R, 6S and l'S, 5S, 6R) 6-1' - (hydroxyethyl) -2- (2-azodoethoxymethyl) -penem-3-carboxylic acid (isomer B)

CH2och2CH2N3

co2pnb

OH

A solution of 180 mg (0.400 mmol) (l'R, 5R, 6S and l'S, 5S, 6R) p-nitrobenzyl-6- (l'-hydroxyethyl) -2- (2-azidoeth-oxymethyl) -penem-3 carboxylate (isomer B) in 18 ml THF was mixed with 19 ml ether, 18 ml water and 180 mg 10% Pd / C. The mixture was then hydrogenated at 380 kPa at room temperature for 2.5 h. After filtering off the catalyst, the aqueous filtrate was washed with EtOAc and lyophilized, 84.4 mg (0.298 mmol, crude yield 73.2%)

the desired compound was obtained in the form of a crude yellowish powder. UV (H20) Àniax: 305.5 (s 4800) and 255 mA. (e 3800). This powder was purified by hplc (Waters C | S Micro Bondapack reverse phase 30 cm x 10 mm, elution 65 medium 1% CH3CN in H20) and gave 44.7 mg (0.155 mmol, yield 38.8%) of the desired compound in the form of a white powder. 'Hmr (D-> 0) 5: 1.34 (3H, d, J = 6.4Hz, CHy-1'), 3.26 (2H, m, -CH2N). 3.82 (2H, m,

43

643 846

-OCH2CH2-), 3.94 (IH, dd, J6,. = 6.2Hz, J6 5 = 1.4Hz, H-6), 4.2-4.4 (1 H, m, H-l ' ), 4.52-4.70-4.84-5.02 (2H, AB type, CHt-2) and 5.71 ppm (1H, d, J = 1.3Hz, H-5). IR (KBr disk) vmax: 3420 (OH), 3000-2600 (br, C02H), 1765 (ß-lactam) and 1575 cm "1 (-C02H). UV (H20) A.raax: 306 (s 5300) and 258 mu (e 3600).

Example 7

2- (2-aminoethoxymethyl) -penem-3-carboxylic acid (via mercaptide intermediate)

rrVcH2OCK2CH2NH2 ■

io

Ethyl 2-chloroethoxyacetate

C1CH CO Et + 2 2

V

TEAB

150-160 ° C

A mixture of 24.5 g (0.200 mol) of ethyl chloroacetate, 8.80 g (0.300 mol) of ethylene oxide and 0.40 g (1.9 mmol, dried in vacuo) tetraethylammonium bromide was in the bomb tube at 150-160 ° C for 6 h heated. After cooling, the reaction mixture was distilled in vacuo using 6.66 g (54.4 mmol, 27.2%) of ethyl chloroacetate, b.p. 22-24 ° C (0.5 mmHg) and 8.39 g (50.4 mmol) , 25.2%) of ethyl 2-chloroethoxyacetate were obtained in the form of a colorless oil. Bp 49-53 ° C (0.1 mmHg). 'Hmr (CDCI3) 5: 201.28 (3H, t, J = 7Hz, -CH3), 3.5-4.0 (4H, m, A2B2, -CH2CH2-C1), 4.15 (2H, s , -C0CH20-), 4.25 ppm (2H, q, J = 7Hz, -OCH2CH3). IR (neat) vmax: 1740 cm "'(C = O ester). Method by D. Klamann and co-workers, Justus Liebig Ann., 710, 59 (1967) (Reported: yield 42%, bp 25 55,570.35 mm Hg).

Ethyl 2-azidoethoxyacetate

EtO

NaN

EtO

DMF

A mixture of 7.71 g (36.3 mmol) of ethyl 2-chloroethoxyacetate and 3.31 g (50.9 mmol) of sodium azide in 100 ml of DMF was heated to 80-90 ° C. over 3.5 h, after this time tic (hexane, ether, 1: 1) was used to demonstrate that the reaction had ended. The cooled mixture was poured into 1 liter of H20 and extracted 3 times with 250 ml of ether. The extracts were washed twice with H20 and once with brine, dried over MgSO4 and to 7.16 g

(41.4 mmol, 89.4%) ethyl 2-azido ethoxyacetate evaporated in the form of a yellowish oil. 'Hmr (CDC13) 5: 1.30 (3H, t, J = 7Hz, -OCH2CH3), 3.3-4.0 (4H, m, -OCH2CH3N3), 4.13 (2H, s, -C0CH20- ), 4.23 ppm (2H, q, J = 7Hz, -OCH2CH3). IR (neat) vmax: 2100 (N3 and 1750 cm-1 (C = 0 ester). This product was used in the next step without working up in the next step.

2-azidoethoxyacetic acid

NaOH

H O-MeOH

To a solution of 6.56 g (37.9 mmol) of ethyl 2-azido-ethoxyacetate in 80 ml MeOH was added 80 ml IN aqueous NaOH and the resulting mixture was stirred at room temperature overnight (17 h). After removing the insoluble, the methanol was evaporated, in vacuo and it was saturated with sodium chloride and washed 3 times with 30 ml of ether. The aqueous phase was acidified with 30 ml of 3N HCl and extracted 4 times with 40 ml of ether. The ether extracts were washed with brine, dried over MgSO4 and evaporated to 4.25 g (29.3 mmol, 50 77.3%) of 2-azidoethoxyacetic acid in the form of a colorless oil. 'Hmr (CDC13) 5: 3.3-4.0 (4H, m, -0CH2CH2N3), 4.22 (2H, s, -C0CH20-), 9.52 ppm (IH, s, -C02H, exchanged with D20). IR (neat) vmax: 2600-3300 (br, -C02H), 2100 (azide) and 1740 cm "1 (C = 0-C02H). 55 This product was used in the next step without refurbishing.

2-azidoethoxyacetyl chloride

SOCI.

A solution of 2.09 g (14.4 mmol) of 2-azidoethoxyacetic was evaporated in vacuo. The oil thus obtained was dried in Va acid in 5 ml of thionyl chloride and was dried at room temperature in a vacuum of 65 (water jet) over NaOH for 1 h while stirring for 4 h. The excess thionyl chloride where 2.23 g (13.6 mmol, 94.4%) of 2-azidoethoxyacetylchloro

was removed in a water jet vacuum and the residue was obtained as a colorless oil. 'Hmr (CDC13) 5: 3.43 dissolved in 10 ml of benzene (dried over molecular sieves) and (2H, br, t, J = 5Hz, -CH20-), 3.78 (2H, br, t, J = 5Hz ,

643 846

44

-CH2N3) and 4.50 ppm (2H, s, -C0CH20-). IR (neat) vmax: 2100 (azide) and 1800 cm-1 (-COC1). This product was used in the next step without refurbishment.

4- (2'-Azidoethoxyacetylthio) -l- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azetidinone

-Say

Pyr / CH2C12

<r ~

c02pnb

To a stirred solution of 7.96 g (12.0 mmol) of silver l- (paranitrobenzyl-2'-triphenylphosphoranylidene-2'-acetate) -2 'azetidinone-4-thiolate in 100 ml of CH2C12, containing 1.94 ml (24.0 mmol) of pyridine was added at 0-5 ° C under nitrogen with a solution of 2.23 g (13.6 mmol) of 2-azidoethoxyacetyl chloride in 20 ml of CH2C12 and the mixture was stirred at room temperature for 2 h. After the precipitate had been filtered off, the filtrate was evaporated and the remaining oil was worked up by column chromatography (Si02.160 g, eluent EtOAc: CH2Cl2 = 1: 1), 4.216 g (6.17 mmol, 51.4%) of the desired phosphorane in

CO PNB 2

Form of a yellow foam were obtained. This foam -2o was used as such in the next step. An analytical sample was obtained by crystallization from CH2C12 ether (1: 9). M.p. 128-129 ° C (dec.). IR (Nujol) vmax: 2090 (-N3), 1755 (β-lactam) and 1690 cm-1 (thioester).

Analysis for C34H30N5O7PS 25 Calculated: C, 59.74 H, 4.42 N, 10.26 Found: C, 59.33 H, 4.49 N, 9.69 tic (EtOAc) Rf = 0.55.

p-nitrobenzyl-2- (2-azidoethoxy) methyl-penem-3-carb-oxylate toluene.-

S, 4.69 S, 5.19.

CO PNB 2

A cloudy solution of 4.13 g (6.04 mmol) of said phosphorane in 200 ml of toluene was refluxed under nitrogen for 1.5 h. After the insolubles had been removed, the solvent was evaporated off in vacuo and the residue was purified by column chromatography (SiO 2, 80 g, eluent 5% ether in benzene), giving 2.44 g (6.02 mmol, 99.6%) of the desired compound in the form of a yellowish oil. This oil was used in the next step without working up. After recrystallization from CH2C12 ether (1: 9), an analytical sample was obtained. M.p. 88-89.5 ° C. 'Hmr (CDC13) 8: 3.35 (2H, t,

H och ch n 2 2 2 3

co2pnb

J = 5Hz, -OCH2-), 3.47 (1H, dd, Jgem = 16Hz, Jtrans = 2Hz, C6-H), 3.67 (2H, t, J = 5Hz, -CH2N3), 3.85 ( IH, dd,

Jgcm = 16Hz, Jcis = 3.5Hz, QH), 4.73 (2H, ABq, J = 16.19, 45 C2-CH2), 5.30 (2H, ABq, J = 13.5.9, - OCH2Ar), 5.63 (IH, dd, J (rans = 2Hz, Jcis = 3.5Hz, C5-H), 7.50-7.63-8.12-8.27 ppm (4H, A2'B2 ', aromatic Hs). IR (Nujol) vmax: 2100 (-N3), 1785 (ß-lactam) and 1695 cm-1 (ester). UV (EtOH) A, max: 263 mji (e 12 000), 320 , 5 mn (e9600) tic (benzene: ether = 1: 1) 50 Rf = 0.60.

2- (2-aminoethoxy) methyl penem-3-carboxylic acid

py

co pnb 2

CH2och2CH2N3

H2 / Pd-C #

■ 0_CH2 ° CH2CH2NH2

co2h

A solution of 1.62 g (4.00 mmol) of the said azitoder in 50 ml of dimethoxyethane was mixed with 50 ml of ether, 50 ml of water and 1.62 g (Engelhard) 10% Pd / C and at room temperature and 380 kPa hydrogen hydrogenated for 2.5 h. After filtering off the catalyst, the aqueous phase was washed twice with 50 ml ether and once with 50 ml EtOAc. The aqueous solution was lyophilized to give 817 mg (3.34 mmol, 83.6%) of the desired amino acid as a yellowish powder. UV (HzO) X.max: 304 mji (e 5000). This product was worked up by hplc (Waters, C | 8 Micro Bondapak Reverse Phase 30 cm x 10 mm, eluent 1% CH3CN in H20) to give 432 mg (1.77 mmol, 44.2%) of the desired amino acid in the form of a white powder. 'Hmr (D20) 8: 3.19-3.9

45

643 846

(4H, m, -OCH2CH2NH2), 3.54 (IH, dd, Jgcni = 16.9Hz, J, ™ "= 1.9Hz, Cs-H), 3.88 (1H, dd, Jgcm = 16.8Hz , Jcis = 3.7Hz, Cfi-H), 4.52-4.70-4.83-5.01 (2H, AB type, C2-CH20-) and 5.77 ppm (1H, dd, Jcis = 3.6Hz, Jlrans = 1.9, QH). IR (KBr Schcibc) vmax: 1770 (β-lactam) and 1580 cm-1 (-C02H). UV (H20) Xmu: 304 mjj. (e 5400), 256 mji (e 3100).

Example 8

2- (2-Aminoethylthiomethyl) -pcncm-3-carboxylic acid (via Mcaptide intermediate)

2-azidoethyl methanesulfonate

BrCH2CH2OH - * N3CH2CH2OMs

A solution of 7.5 g (60.0 mmol) of bromoethanol and 5.0 g (76.9 mmol) of sodium azide in 30 ml of HMPT was heated to 115 ° C. over 2.5 h. The reaction mixture was cooled to 23 ° C and diluted with 100 ml CH2C12, the solids were filtered off and the CH2C12 was evaporated on a rotary evaporator, leaving a yellow liquid, which was cooled to 0 ° C and washed successively with 5.57 ml (72, 0mmol) Mcsylchloride and 10.0 ml (72.0 mmol) triethylamine. The reaction mixture was then stirred at 0 "C for 1 h, and then poured at 23 ° C for 6 h and in 300 ml water. The aqueous solution was extracted once with 200 and 4 times with 100 ml of ether, the ether extracts were combined, washed with IN HCl, saturated NaHC03 and H20, dried over anhydrous MgS04 and evaporated on a rotary evaporator to an orange liquid which was then distilled under high vacuum has been. Bp 95-100 ° C, 0.3 torr,

5.8 g, 58.5%. IR (pure) vmix: 2005 (s, NO, 1345 (s, S02-0), 1175 (m, S02-0) cm- '.' Hmr (CDC13) 5: 3.03 (s, 3H, OCH3) , 3.43-3.76 (m, 2H, H-2) and 4.2-4.46 ppm (m, 2H, Hl).

2'-Azidoethylthioglycolsäurc

5

1. A

N3CH2CH2OMs + NaSCH2COONa>

2. H +

N3CH2CH2SCH2COOH

io

3.14 g (34.1 mmol) of thioglycolic acid were treated with 68 ml (68.0 mmol) of IN NaOH solution and the resulting solution was treated at 23 ° C. for 0.5 h with a solution of 5.3 g (32 , 1 mmol) 2'-Azidoäthylmelhansulfonat in 15 ml of di- »5 methoxyâthan treated. The reaction mixture was stirred at 45 ° C for 22 h, cooled to 23 ° C, washed 3 times with 20 ml of CH2C12, acidified with a 6N HCl solution and extracted 7 times with 40 ml of CH2C12. The CH2C12-Ex-traklc were combined, dried over Na ^ S04 and evaporated to a 01 on a 20 ° rotary evaporator, which was distilled under high vacuum. Bp 117-122 "C / 0.27 torr, 4.2 g, 81.2%. IR (neat) vmn: 2100 (s, N3), 1708 (s, C = 0) cm- '." Hmr (CDC13) 5: 2.7-3.07 (m, 2H, H-1 '), 3.35 (s, 2H, Hl), 3.30-3.73 (m, 2H, H-2') ) and 11.81 ppm (s, IH, COOH), 25 2'-azidoethylthioacetyl chloride

(COCl) 2

N3CH3CH3SCH3COOH * N3CH2CH2SCH2C0C1

30 3.9 ml of oxalyl chloride and 1 drop of DMF were added to a solution of 3.33 g (20.7 mmol) of 2-azidoethyl-thioglycolic acid in 50 ml of CH2C12. The reaction mixture was. Stirred at 23 ° C for 1.5 h and the solvent was removed on the rotary evaporator leaving a yellow liquid. IR (neat) vmax: 2100 (s, N3), 1785 (bs, C = 0). "Hmr (CDCIj) 5: 2.6-3.0 (m, 2H, H-1 '), 3.37-3.73 (m, 2H, H-2') and 3.82 ppm (s, 2H, Hl).

4- (2'-AzidoethyIthioacctylthio) -l- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azctidinone

f

-N

Say

ï = pph3 COOPNB

C1CCK SCH CH N 2 2 7 ^

ff

JSCCH2SCH2CH2N3

cr ~ N \ ~ _.

: PPh.

COOPNB

A solution of 15.7 mmol of silver 1- (paranitrobcnzyl-1-5) evaporation of the solvent 7.7 g (70%) of a white triphcnylphosphoranylidcn-1'-acctate) -2-azctidinone-4-thiolate powder. An analytical sample was obtained by circulating and 1.6 ml (19.8 mmol) of pyridine in 200 ml of CH2C12 was obtained from CH2Cl2 ether / petroleum ether, mp. 150-151 ° C.

dropwise during 0.25 h with a solution of 3.64 g (dec.).

(20.3 mmol) 2'-azidoethylthioacctyl chloride in 50 ml CH2C12 analysis for C34H30N5O6S2P

treated. The reaction mixture was calculated at 23 ° C for 60: C, 58.36 H, 4.32 N, 10.01 S, 9.17 for 1.5 h and filtered, the solids were found with CH2C12: C, 58, 64 H, 4.36 N, 10.03 S, 9.25 washed and the filtrate and the wash solutions were IR (KBr) vmax: 2100 (s, N3), 1750 (s, C = O vom ß-Lac-

Clean and wash with O, INHCI, water, saturated NaHC03 and camouflage), 1675 (s, C = 0), 1655 (s, C = 0), 1610 (s, aromatic) water, dried over Na2S04 and on the ro and 1440 cm "1 (s, P-Ph).

Lation evaporator evaporated to an orange syrup. Acid chromatography of 65 paranitrobenzyl-2-aminoethylthiomcthylpenem-3-carb chromatography (300 g silica gel G-60, eluent oxylate EtOAc in CH2C12.0-40%) gave the crude compound

643 846

46

, SCCH2sch2CH2N3

• n.

'<j> PPh3 coopnb ch2SCH2CH2N3

coopnb

A suspension of 4.5 g (6.43 mmol) of 4- (2'-azidoethyl-thioacetylthio) -1 - (paranitrobenzyl-2 "-triphenylphosphoranylidenyl acetate) -2-azetidinone in 375 ml of toluene was at 110 ° C during The reaction mixture was cooled to 23 ° C. and an orange-colored syrup was obtained after evaporating off the solvent on a rotary evaporator. The crude product was worked up on a silica gel column (90 g silica gel G-60, eluent: ether / petroleum ether) , 1: 1-3: 2), the pure product

lo gave 2.2 g (81%) of a yellow colored syrup. ir (pure) vmax: 2100 (s, N3), 1785 (s, C = Ovom ß-lactam), 1705 cm "1 (s, C = O from PNB). 'Hmr (CDC13) 5: 2.53- 2.90 (m, 2H, H-1 "), 3.30-3.67 (m, 3H, H02", H-6 trans), 3.98 (ABq, J.lb = 14.8Hz, 2H , H-l '), 5.32 (ABq, Ja_b = 13.0Hz, 2H, CH2-PhN02), 5.66 15 (dd, Jh-5, H-6 eis = 3.6Hz, Jh ~ 5. H6 trans ~ 1.9Hz, 1-H, H-5), 7.58 (d, JHo Hm - 8.8Hz, 2H, Ho PNB) and 8.19 ppm (d, JHm_ ho = 8.8Hz, 2H, Hm PNB).

2-aminoethylthiomethylpenem-3-carboxylic acid

I rf — c ^^ sch ch_n.

coopnb

2 2 3

H2sch2CH2NH3

To a solution of 45 mg (0.11 mmol) of p-nitrobenzyl-2-azidoethylthiomethylpenem-3-carboxylate in 5 ml of dimethoxyethane was added 5 ml of ether, 5 ml of water and 45 mg (0.11 mmol) of 10% Pd / C . The reaction mixture was hydrogenated at 45 psi hydrogen for 3.0 h at 23 ° C and filtered through Celite. The filter was washed with water and the filtrate and washing solutions were combined and diluted with ether. The aqueous phase was separated and washed with ether and lyophilized. 20 mg of the crude compound was worked up by hplc. 5 mg, 18%. IR (KBr) vmax: 1765 (C = 0), 1600 cmT1 (b, COO "). 'Hmr (D20) §: 2.70-3.00 (m, 2H, Hl"), 3.15-3 , 45 (m, 2H, H-2 "), 3.49 (dd, Jgem = 16.8Hz, J6-5 trans = 1.7Hz, H-6 trans), 3.85 (dd, Jgem = 16, 8Hz, cis = 3.4Hz, H-6 ice), 4.05 (ABq,

30th

Yes-b = 14.6Hz, 2H, H-1) and 5.74ppm (dd, J5 6cis = 3.4Hz, J5 6 tran5 = 1.7Hz, 1H, H-5). UV lmax: 307 (e 4330), 250 (s 3282).

Example 9

2- (2-aminoethylsulfonylmethyl) -penem-3-carboxylic acid ch2ch2nh2

para-nitrobenzyl-2- (2-azidoethylsulfonylmethyl) -penem-40 3-carboxylate ch sch ch n 2 2 2 3

mcpba

CH2C12

osIX> -J

coopnb

> ch2CH2N3

A solution of 0.36 g (0.85 mmol) of p-nitrobenzyl-2-azo-diethylthiomethylpenem-3-carboxylate in 30 ml of CH2C12 was cooled to -20 ° C and dropwise under nitrogen (2 h) with a solution of 0.147 g (0.85 mmol) of m-chloroperbenzoic acid in 90 ml of CH2C12. The reaction mixture was stirred at -20 ° C for 0.5 h, allowed to warm to room temperature and washed with a saturated NaHCO 3 solution and water. The organic solution was dried over anhydrous Na2SO4 and concentrated in vacuo to give an orange residue which was chromatographed on silica gel (silica gel G 60.9 g, eluent: 25% EtOAc in CH2C12, fraction size: 7 ml). Evaporation of the appropriate fractions gave a white solid: 0.27 g, mp. 128-131 ° C, 72.6%. After recrystallization from acetone-ether-petroleum ether, an analytical sample was obtained. Mp 142 ° C (dec.).

Analysis for Q 6H506S2 Calculated: C, 43.93 H, 3.46 N, 16.01 S, 14.66 Found: C, 43.79 H, 3.44 N, 16.02 S, 14.63.

IR (KBr) vmax: 2110 (N3), 1785 (C = 0 from ß-lactam), 1690 (C = 0 from PNB ester), 1600.1560 (C = C), 1520,

55 CHC13

1355 cm-1 (N02). UV X: 265 (e 12 884), 333 (e 8764).

Max

'Hmr (CDC13) 5: 2.95 (2H, m, CH2CH2N3), 3.58 (dd, JH-sh-5 trans = 2.0Hz, Jgcm = 16.6Hz, H-6 trans), 4.33 (Center of 60 ABq, yes b = 13.4Hz, H-1 '), 4.32 (center of ABq, yes, b = 13.2Hz, H-1'), 5.33 (center of ABq, yes - b = 13.7Hz, 2H, CH2 from the PNB ester), 5.75 (dd, Jh-5-h-6 eis = 3.6Hz, Jh-5 h ö trans = 2.1 Hz, IH, H -5), 7.60 (d, JHo Hm = 8.8Hz, 2H, Ho from PNB ester) and 8.22 (d, JHm Ho = 8.8Hz, 2H, Hm from 65 PNB ester).

2- (2-aminoethylsulfonylmethyl) -penem-3-carboxylic acid

d>

H2SCH2CH2N3

47

10% Pd / C

643 846

DME, Et20, H20

COOPNB

COOH

ch2Sch2ch2nh2

To a solution of 57 mg (0.13 mmol) of paranitrobenz-yl-2- (2-ethylsulfonylmethyl) -penem-3-carboxylate in 20 ml of dimethoxyethane was added 10 ml of Et20.10 ml of water and 57 mg of 10% Pd / C given. The reaction mixture was hydrogenated at 380 kPa hydrogen for 1.25 h and then filtered through Celite. The filtrate was diluted with Et20, the organic phase was separated and the aqueous solution was washed twice with Et20 and lyophilized. The crude orange powder (30 mg) was worked up by hplc; Lyophilization of appropriate fractions gave the desired compound as a white powder.

h2o ver. 10.4 mg (29%). UV X: 313 (e 4877). IR (KBr) vmax: max

1720 (C = O from β-lactam) and 1590 (carboxylate). 'Hmr (D20) 5: 3.0-3.7 (5H, H-6 trans, CH2CH2NH3 +), 3.90 (dd,

JH-6-H-5 eis = 3.6Hz, Jgem = 16.9Hz, IH, H-6 eis), 5.45 (center of ABq, Ja b = 13.6Hz, H-l '), 4, 50 (center of ABq, Yes 15 b = 13.6Hz, H-1 ') and 5.8 (m, IH, H-5).

Example 10

Silver l- (β-trimethylsilylethyl-2'-triphenylphosphoranyli-den-2'-acetate) -2-azetidinone-4-thiolate

Say

20th

25th

'N ^ P43

/ CH3

2CH2CH2Si - CH3

CH.

di-ß-trimethylsilylethyl fumarate

Cl

Cl

HO

■ SiCCH ^

Pyridine

'(CH) Si

To a cold (- 10 ° C) solution of 4.73 g (0.04 mmol) 2-trimethylsilylethanol (H. Gerlach Helv. Chim. Acta 60, 3039 (1977)) in 20 ml ether and 5.66 ml ( 3.77 ml (0.035 mol) of fumaryl chloride, dissolved in 10 ml of ether, were added dropwise under nitrogen over a period of 15 min. The black mixture was stirred at -10 ° C for 5 min and then at room temperature for 10 min, activated carbon was added and the reaction mixture was filtered through Celite. The filtrate was washed with 1% sodium bicarbonate sodium chloride solution (1: 1.150 ml), the aqueous phase was extracted with 30 ml ether, the ether solutions were combined, washed with brine, dried over sodium sulfate, filtered and evaporated in vacuo, whereby a 50th

brown solid was obtained. This compound was chromatographed on silica gel (30 g, 4 x 5 cm) and eluted with 300 ml of benzene to give 4.855 g (77%) of an oil which crystallized on standing.

Analysis for Ci4H2804Si2 Calculated: C, 53.12 H, 8.91 Found: C, 53.35 H, 8.91.

Hmr (CDCI3) 5: 6.78 (2H, s, C = CH), 4.26 (4H, m, CH2-0), 1.03 (4H, m, CH2-Si) and 0.06 ppm (18H, s, (CH3) 3Si). IR (CHC13) v max: 1710 (C = O from the ester), 1643 (C = C), 1267, 1258.862 and 840 cm "1 (Si-C).

Trimethylsilylethylglyoxylate hydrate

(CH3) 3Si

Si (CH3) 3

D O.

2) (CH3) 2S

: H (OH)

2 ^ Si (CH3) 3

A solution of 37 g (0.117 mmol) of di-β-trimethylsilyl-ethyl fumarate in 1.1 liters of methylene chloride was ozonized at -78 ° C until there was a permanent blue color. The excess ozone was purged with nitrogen and 2.57 ml (0.351 mol) of dimethyl sulfide were added. The solution was allowed to warm up slowly to 23 ° C, the reaction mixture was then made up to 2 liters with carbon tetrachloride and with 1% aqueous solution of sodium carbonate

(500 ml) washed. The organic phase was dried over sodium sulfate, filtered through Celite and evaporated (25 ° C), whereby 43.9 g of the desired compound were obtained (97%). IR (neat) vmax: 3450 (-OH), 1740 (ester), 1255, 65 860 and 840 cm "'(Si-C).

1- (β-Trimethylsilylethyl-2'-hydroxy-2'-acetate) -4-tritylthio-2-azetidinone

643 846

48

vT

y nNÌ

f

CO

(OH)

2 SiCH.

4,000 g (11.6 mmol) of trimethylsilylethylglyoxylate hydrate and 4.8 g (24.96 mmol) of 4-tritylthio-2-azetidinone were refluxed in 25 ml of benzene on the Dean-Stark apparatus under nitrogen for 24 h. The solvent was evaporated in vacuo, the product was chromatographed on a silica gel column (450 g, 8.5 x 14.5 cm) and eluted with ethyl acetate: methylene chloride (1:19) until the desired compound started to appear (about 1.5 liters) and then eluted with ethyl acetate: methylene chloride (1: 9.2 liters). The fractions containing the desired compound were vereiSi (CH3) 3

ned and concentrated to dryness, yielding 5.415 g (89%) of the desired compound. 'Hmr (CDC13) S: 7.80 to 6.70 io (15H, m, trityl), 5.23 and 4.90 (IH, 2s, HCO), 4.50 to 4.10 (3H, m, H-3 and 0-CH2), 2.60 (2H, m, H-2), 0.95 (2H, m, CH2-Si) and 0.1 ppm (9H, s, Si-CH3). IR (CHC13) vmax: 3520 (-OH), 1765 (C = Ò from ß-lactam), 1740 (C = 0 from ester), 1595 (CH, aromatic), 1257.860 and 840 cm-1 (C- Si).

15

1- (ß-Trimethylsilylethyl-2'-chloro-2'-acetate) -4-tritylthio-2-azetidinone

STr

SOCI.

pynain

Si (CB3> 3

STr

CO.

Cl

, Si (CH3) 3

A solution of 0.74 ml (10.37 mmol) of thionyl chloride in solvent gave a residue which was passed through silica gel

9 ml of dry THF was added dropwise with stirring to a solution of 4.9 g (9.37 mmol) of 1- (β-trimethylsilylethyl-2'-hydroxy-2'-acetate) -4-tritylthio-2-azetidinone, 0, 84 ml (10.38 mmol) of pyridine and 40 ml of dry THF at -15 ° C. and under nitrogen were added. The mixture was stirred at -15 ° C for 2 h, the precipitate formed was filtered off through Celite and washed with 50 ml of benzene. The filtrate was evaporated in vacuo at 30 ° C., the residue was dissolved in 100 ml of benzene, treated with activated carbon and filtered through Celite. Evaporation of the

was filtered (100 g, 4.7 x 11 cm) and eluted with hexane-benzene (1: 1,400 ml), ether-benzene (1: 19.1 liters). Evaporation of the appropriate fractions gave 4.64 g of the desired compound (92%). 'Hmr (CDC13) 5: 7.30 (15H, 35 m, aromatic H), 5.77 and 5.43 (IH, 2s, CH-Cl), 4.7 to 4.2 (3H, m, H -4 and CH2-0), 2.85 to 2.50 (2H, m, H-3), 1.15 (2H, m, CH2-Si) and 0.06 ppm (9H, s, Si-CH3 ). IR (pure)

Vmax: 1760 (C = O), 860 and 840 cm "'(C-Si).

l- (ß-Trimethylsilylethyl-2'-triphenylphosphoranyliden-2'-

4o acetate) -4-tritylthio-2-azetidinone si (oy3

A solution of 4.12 g (7.568 mmol) of said chlorazetidinone in 20 ml of dioxane was treated with 2.209 g (8.424 mmol) of triphenylphosphine and 0.98 ml (8.424 mmol) of 2,6-lutidine. The mixture was refluxed for 3.5 h, the cooled solution was filtered and the white solid washed with THF. The filtrate was then evaporated to dryness, the residue was applied to a silica gel column (200 g, 4 x 31 cm) using ethyl acetate-hexane (3: 7.1 liters, 7: 3.1 liters) as eluent worked up and gave 4.836 g (83%) of the desired Phos-50 phoran. IR (film) vmax: 1755 (C = O), 1615 (phosphorane), 850 and 830 cm "'(Si-C).

Analysis for C47H46N03PSSi Calculated: C, 73.89 H, 6.07 N, 1.81 Found: C, 72.18 H, 6.08 N, 1.83. 55 silver l- (β-trimethylsilylethyl-2'-triphenylphosphoranyli-den-2'-acetate) -2-azetidinone-4-thiolate i (CB3) 3

+ AgNO + (nBu) N + CF CO E

3 3 3 2 etner / Eo0

Say

Si (CR3)

49

643846

7.64 g (10 mmol) of l- (β-trimethylsilylethyl-2'-triphenyl-phosphoranylidene-2'-acetate) -2-azetidinone were dissolved in 60 ml of ether. An aqueous solution of silver nitrate (0.5M, 80 ml, 40 mmol) was added, followed by rapid addition (1 min) of a solution of 3 ml (12.58 mmol) tributylamine and 0.154 ml (0.2 mmol) ) Trifluoroacetic acid in 20 ml ether. The mixture was stirred mechanically for 90 min, the precipitate formed was filtered off, rinsed with 200 ml of ether, shaken in 70 ml of water, filtered again and rinsed with 100 ml of ether. The pale brown solid was dried in vacuo (water jet vacuum 10 min and pump 65 min) and gave 6.42 g of the desired compound. IR (CHC13) v max: 1862 (C = 0), 1630 (phosphorane), 860 and 840 cm "1 (Si-C).

Example 11

Silver 3- (1 '-hydroxy-1' -ethyl) -1 - (ß-trimethylsilylethyl-2 "-triphenylphosphoranylidene-2" -acetate) -2-azetidinone-4-thiolate

SiMe.

trans-3-acetyl-1 - (β-trimethylsilylethyl -2'-triphenylphosphoranylidene-2'-acetate) -4-tritylthio-2-azetidinone

1. LDA

2. EtOAc

SiMe.

SiMe.

4.0 ml (6.0 mmol) of n-butyllithium were added to a solution of 0.80 ml (5.5 mmol) of diisopropyl-25 amine in 25 ml of tetrahydrofuran at -78 ° C. with stirring. After 3 min, a solution of 3.82 g (5.00 mmol) of l- (β-tri-methylsilylethyl-2'-triphenylphosphoranylidene-2'-acetate) -4-tritylthio-2-azetidinone in 40 ml of tetrahydrofuran was added dropwise during Added 20 min with stirring. After 2 minutes, 2.5 ml (25 mmol) of ethyl acetate was added to the solution and stirring was continued for a further 10 minutes. The cooling bath was removed and 58 ml of 0.2M hydrochloric acid was added with vigorous stirring. Then 65 ml each of water and ethyl acetate were added, the mixture was shaken and separated. The organic phase was washed with water and saturated sodium chloride solution (60 ml each), dried and the solvent was evaporated in vacuo to give 4.1 g of the crude product. 40

30th

35

This product was adsorbed onto 20 g of silica gel from methylene chloride and added dry to 120 g of silica gel column. The column was eluted with ether / hexane 1: 1 (200 ml) and then with 500 ml ether. Evaporation of the solvent from the appropriate fractions gave partially purified desired compound (2.17 g, 53%). IRvmax: 1755 (β-lactam and ester) and 1710 cm-1 (ketone). 'Hmr (CDC13) 8: 1.67 and 1.87 peaks for

O

II

CH3C, trimethylsilyl and aromatic peaks; Rest badly resolved.

3- (l'-Hydroxy-l'-ethyl) -l- (ß-trimethylsilylethyl-2 "-triphery-ylphosphoranylidene-2" acetate) -4-tritylthio-2-azetidinone

Me '

j [STr

NaBH

A solution of 2.10 g (2.60 mmol) of said compound in 20 ml of tetrahydrofuran was added to a slurry of 160 mg (4.3 mmol) of sodium borohydride in 10 ml of tetrahydrofuran. The mixture was stirred at 23 ° C for 4 h, 30 ml water was added, followed by slow addition of 1M hydrochloric acid until pH 3 was reached. The mixture was extracted with 50 ml of ethyl acetate, the organic phase was washed with 50 ml of 0.1M sodium bicarbonate, 50 ml of dilute sodium chloride solution and 50 ml of saturated sodium chloride solution, dried and the solvent was evaporated in vacuo to give 2.22 g of the crude Product. The product was adsorbed onto 11 g of silica gel from methylene chloride and added dry to 44 g of silica gel column. The column was eluted with ether, and after evaporating the solvent from 60 of the appropriate fractions, partially purified compound 1.43 g (68%) was obtained. 'Hmr (CDC13): peaks around 8 1 for

OH

I.

65 CH3C H, trimethylsilyl and aromatic peaks, rest poorly resolved.

Silver 3- (1'-hydroxy-1 '-ethyl) -1- (β-trimethylsilylethyl-2 "-triphenylphosphoranylidene-2" -acetate) -2-azetidinone-4-thiolate

643846

50

O

STr

N.

AgNO.

CO.

.SiMe.

OK

Me

Say

ó * ~ K y ^ Ph:

CO.

-SiMe.

/>—CK._CCE.CH.NH // 2 2 2 2

A solution of 1.43 g (8.4 mmol) of silver nitrate in 40 ml of water and a solution of 0.27 ml (3.35 mmol) of pyridine and 1.35 g (1.67 mmol) of said phosphorane in 40 ml of ether was stirred vigorously at 23 ° C. for 1 h. The precipitate was filtered off, washed with water and ether and dried, giving 1.24 g (100%) of the desired compound. IR vmax: 3420 (OH) and 1750 cm-1 (β-lactam and ester).

(Isomer B)

Example 12 (l'R, 3S, 4R and l'S, 3R, 4S) 4- (2-azidoethoxyacetylthio) -

(l'R, 5R, 6S and l'S, 5S, 6R) 6- (l'-hydroxyethyl) -2- (2-25 3- (l'-hydroxyethyl) -l- (β-trimethylsilylethyl-2 "-triphenylphos) -aminoäthoxymethyl) -penem-3-carboxylic acid (isomer B) alter-phoranylidene-2 "acetate) -2-azetidinone native method

s f

SCOCH OCH CHN 2 2 2 3

1.54 ml (11.8 mmol). Trimethylsilyl chloride was added to a stirred slurry of 2.48 g (3.34 mmol) of silver-ber-3- (l'-hydroxyethyl) -l- (β-trimethylsilylethyl-2 " -triphenyl-phosphoranylidene-2 "acetate) -2-azetidinone-4-thiolate (isomer B), 136 mg (2.0 mmol) of imidazole and 1.64 ml (11.8 mmol) of triethylamine in 60 ml of THF at 0 ° C added. The mixture was stirred at 23 ° for 18 h, 60 ml of methylene chloride were added, it was cooled to -15 ° C and 1.32 ml (16.4 mmol) of pyridine and 1.43 g (8.70 mmol) of β-azi -Doethoxyacetyl chloride were added and the mixture was stirred at -15 ° C for 0.5 h. 60 ml ether, 60 ml ethyl

40 acetate and 20 ml IM hydrochloric acid were added. The precipitate formed was filtered off and the organic phase was washed with 100 ml of 0.1M hydrochloric acid, 100 ml of 1% sodium bicarbonate and saturated sodium chloride solution. After evaporating the solution, the crude desired compound was obtained as an oil. 85%. IR vmax: 1755 and 1695 cm-1.

(l'R, 5R, 6S and l'S, 5S, 6R) -ß-trimethylsilylethyl-2-ß-azidoäthoxymethyl-6- (1'-hydroxyethyl) -penem-3-carboxylate (isomer B)

50

, SCOCH2OCH2CH2N3

CO.

ch2OCH2CH2N3 y i—

\

A solution of 1.3 g of the above phosphorane in 200 ml of toluene was heated to reflux for 3 hours. After evaporating the solvent on a rotary evaporator, the crude desired compound was obtained. Chromatography on 40 g of silica gel and elution with increasing proportions of ether in hexane gave the desired crystalline compound at 65%. IR vmax: 1760 and 1700 cm ~ '. 'Hmr indicated contamination with a second 65 isomer.

(l'R, 5R, 6S and l'S, 5S, 6R) -2-ß-Azidoäthoxymethyl-6- (l'-hydroxyethyl) -penem-3-carboxylic acid (isomer B)

51

643 846

OH

: H20CH2CH2N3

A solution of 3 ml (1.5 mmol) of anhydrous tetrabutylammonium fluoride in THF was added to a solution of 155 mg (0.37 mmol) of said ester in 2 ml of THF at 0 ° C. After 5 min at 0 ° C., 10 ml of water and 10 ml of ethyl acetate were added, the mixture was brought to pH 3 with 1M hydrochloric acid and the phases were separated. The organic phase was extracted with 0.05M sodium bicarbonate, the aqueous extracts were brought to pH 3 with HCl and extracted with ethyl acetate. The organic ex

The tracts were washed with saturated sodium chloride solution, dried and evaporated on a rotary evaporator and the residue obtained was shaken with ether and gave 27 mg (28%) of the desired compound as a solid. IR vmax: 3500, 1785, 1670 cnr1. 'Hmr (CDC13) δ: 15 1.30 (3H, d, J = 6.5, CH3-1'), 2.22 (IH, OH), 3.1-3.9 (5H, m, CH2 and H-6), 3.9-4.4 (IH, m, H-1 '), 5.60 (IH, d, J = 1, H-5).

(l'R, 5R, 6S and l'S, 5S, 6R) 6- (l'-hydroxyethyl) -2- (2-aminoethoxymethyl) -penem-3-carboxylic acid (isomer B)

CO H 2

: H2OCH2CH2NH2

A solution of 150 mg of said azido compound 35 phase) gave 46.7 mg of the pure desired compound,

in 15 ml of THF, 15 ml of ether and 15 ml of water was hydrogenated in the Parr apparatus in the presence of 150 mg of 10% Pd / C at an initial pressure of 414 kPa hydrogen. After 3 h the catalyst was filtered off through Celite and the aqueous phase was washed with ethyl acetate and lyophilized to give the crude desired compound. Work up by hplc (Waters, C18 Micro Bondapack Reverse which was identical to a previously prepared sample made by hydrogenating / hydrolyzing the corresponding azido-p-nitrobenzyl derivative.

Example 13

6-ethyl-2- (2-aminoethoxymethyl) -penem-3-carboxylic acid

^ CH20CH2CH2M2

OAc

CSI

NaHC03

Na2S ° 3

OAc

OAc

I.

II

III

The 1-butenyl acetate (approx. I: 1 mixture of ice and trans isomers) was prepared according to P.Z. Bedoukian, J. Am. Chem. Soc. 66 1325 (1944).

10 ml (11 g, 78 mmol) of CSI were added dropwise to 50 ml of cooled (-15 ° C.) I. The mixture was allowed to warm to 0 ° C over 30 min and then cooled to 65-20 ° C and carefully added to a mixture of 8 ml water, 35 g ice, 18.4 g NaHCO 3 and 6.4 g Na 2 SO 3. The mixture was stirred vigorously at 0 ° C for 30 min, treated with 250 ml of petroleum ether and cooled to -40 ° C.

643 846 52

The solvent was decanted off and the residue was mixed with 28% II and 72% III. Bp 82-85 ° C

treated with another 100 ml of petroleum ether in the same way. (0.01 mm). NMR ô (ppm, CDC13) 7.3 (IH, NH), 5.92 (0.72H,

The combined petroleum ether extracts were treated with 30 ml of water d, J = 4.4, II-H-3), 3.3 (0.28H, d, J = 1.4, III-H-4), 3.3 ( IH,

washed and dried over Na2S04 and the obtained I m, H-3), 2.24 (3H, s), 2.72 (2H, 2 q, J = 7), 1.1 (3H, 2t, J = 7 ).

was reinstated in the reaction. 5 vc = 0 1775.1755 cm- '.

The aqueous phases were combined and with 5 analysis for C7HuN03

x 40 ml of ethyl acetate extracted. The extracts were calculated via: C, 53.49 H, 7.05 N, 8.91

Na2S04 dried and in vacuo to 7.0 g (57%) of a gel. Found: C, 53.12 H, 6.93 N, 8.85.

OCOCH.

NaSCOCH.

#

S-COCH.

II + III

IV

Sodium thioacetate was prepared by adding 0.8 ml (850 mg, 11.2 mmol) of thioacetic acid to 11.2 ml of cooled (ice bath) IN sodium hydroxide solution under nitrogen. This solution was added to a cooled solution of 1.57 g (10 mmol) II and III in 5 ml water under nitrogen. The mixture was stirred at room temperature for 1 hour, and since an oil separated, 9 ml of acetone was added and stirring was continued for 1.5 hours. The mixture was then evaporated in vacuo to remove the acetone and extracted with methylene chloride. The ex

The tract was dried and evaporated in vacuo to 1.65 g (95%) of the crude mixture of 85% trans-IV and 15% cis-IV. Bp 105-110 ° (0.02 mm) 7.1 (IH, NH), 5.53 (0.24H, d, J = 4.5, cis-H-4), 5.12 (0, 8H, d, J = 2.4 trans -H-4), 3.34 (IH 2t, J = 7), 2.48 (3H), 1.9 (IH, 2q, J = 7), 1, 15 (3H, 2t, J = 7).

25 vc = 0 1700, 1765 cm- '.

Analysis for C7H! ] N Calculated: C, 48.53 H, 6.40 N, 8.07 Found: C, 48.18 H, 6.47 N, 7.77.

SCOCH.

NH

0 „N- / C) V (

'2 "VI /" CH2 "C02CH (OH) 2

^ Ac

^ CfTOH

IV

C02PNB

A mixture of 1.25 g (7.2 mmol) IV and 1.6 g (7.5 mmol) of p-nitrobenzylglyoxylate in 80 ml of benzene was refluxed in the Dean-Stark apparatus for 20 h, followed by evaporation in vacuo, whereby 3.01 g of the crude product were obtained. This was filtered through a small portion of silica gel in chloroform to give 2.8 g (quantitative) of one

45 pale yellow oil V, containing some solvent. 5 7.9 (4H, m), 5.3 (4H, m), 4.8 (IH, OH), 3.2 (IH, m), 3.37 and 3.33 (3H, 2s), 1.8 (2H, m), 1.05 (3H, m) vc = 01765, 1700 cm "'. This product was used in the next step without refurbishment.

50

scoch.

jthoh co2pnb soci.

COCH.

tpHCl

CO PNB 2

VI

3 ml of thionyl chloride were added to a cooled (ice bath) stirred solution of 2.1 g (5.5 mmol) of V in 10 ml of dry benzene, and the mixture was kept at 5 ° C. for 2 h and then concentrated in vacuo at room temperature.

65 steams. The excess thionyl chloride was removed by repeated addition and evaporation of benzene and the product was purified by filtering the benzene solution over a small portion of silica gel, after evaporation

53

643 846

1.7 g (77%) of the crude pale yellow oil VI 1700.1775 cm 'in vacuo. The product was obtained without working up. 5 7.9 (4H, m), 6.0 (IH, s), 5.3 (3H, m), 3.3 next step.

(IH, m), 2.7 and 2.3 (3H, 2s), 1.75 (3H, m), 1.0 (3H, m) vc = 0

Jâ — COCH.

</ ~

N

CHC1 i

CO PNB 2

lutidine

✓S-COCK.

c / ~ N

f

COOPNB 2

VI

VII

A mixture of 1.7 g (4.2 mmol) of VI, 1.57 g (6.0 mmol) was matographed and the elution was carried out with benzene ether and

Triphenylphosphine and 5.35 mg (5 mmol) of 2,6-lutidine in 20 gave 2.3 g (87%) of crude VII in the form of a pale red

20 ml of dry dioxane was heated to 55 ° C. for 19 h, which was used in the next step without working up, followed by evaporation in vacuo. That went dark.

colored residue was chromatographed on a silica gel column (35 g)

^ ^ s-coch3

s? —ÎK 0

Y

P0-

3rd

COOPNB

VII

AgNO.

base

0

Say

Y

p0.

C02PEB

35

VIII

Mercaptide VIII was prepared from VII by Method 40 from Example 3.

Say

1)

Cl,

4 \ ^ P03 2) TFA

COgPKB

VIII

, K ^ / Pyr

•>

J 0

COgPHB

IX

643846

54

"^ -CE2och2CE2IÌ3

'C02? 1ÎB

H2 / Pd-C

■>

/ N

CE20CE2CH2KE2

Reaction of mercaptide VIII with 2-azidoethoxyacet-yl chloride according to the procedure from example 6 gave intermediate IX, which was cyclized and reduced according to example 6 and gave the desired product.

Biological data

Representative compounds of the present invention have been subjected to in vitro antibiotic screening against a number of different microorganisms. Samples of the specified compounds were examined after dissolving in water and diluting with nutrient medium and gave the minimum inhibitor concentrations (MIC) mentioned below in ng / ml compared to the specified microorganisms, the determination being carried out by incubation at 37 ° C. overnight using the tube dilution method .

MIC in ng / ml organism

Connection (example no.) 6 8 9

20th

Escherichia coli A20341-1

Klebsiella pneumoniae 25 A15130 Klebsiella species A20468

Proteus mirabilis A9900 30 Proteus vulgaris A21559

Proteus morganii A15153

Proteus rettgeri 35 A21203 Serratia marcescens A20019

Enterobacter cloacae A9659 40 Enterobacter cloacae A9656

Pseudomonas aeruginosa A9843A

Streptococcus pneumoniae

Pseudomonas aeruginosa

A9585

.03

.13

.13

.5

45 A21213

Streptococcus pyogenes

Hemophilus influenzae

A9604

.03

.13

.13

.5

A9833

Staphylococcus aureus

A9537

.06

.13

.13

.5

MIC in ng / ml

Staph aureus + 50%

so organism

Serum A9537

.5

1

.5

4th

Staphylococcus aureus

A9606

.25

32

16

4th

Staphylococcus aureus

Haemophilus influenzae

A15097

1

125

16

63

55 A21522

Streptococcus faecalis

Bacteroides fragilis

A20688

4th

32

63

> 63

A20931

Escherichia coli

Bacteroides frabilis

A15119

.5

2nd

4th

8th

A20929

.5

8th

1

32

2nd

4th

8th

32

2nd

> 125

> 63

> 63

1

2nd

4th

8th

1

8th

16

16

4th

8th

8th

16

2nd

2nd

8th

16

2nd

2nd

8th

32

8th

8th

32

32

2nd

4th

32

63

16

63

63

63

8th

125

> 63

63

Connection (example no.) 6 7 8 9

C.

Claims (5)

643 846 PATENT CLAIMS 1. Compound of formula Y. - S (Alk) -A- (Alk «) - R20 j in which Z represents hydrogen or an ester protecting group, Alk represents Q-Qralkylene, optionally substituted by Ci-C4-alkyl, A represents oxygen, sulfur, SO, S02 or NR2i, where R21 is hydrogen, lower alkyl, phenyl or phenyl-lower alkyl, in which Alk 'represents C2-C4-alkylene, in which R20 is a polar substituent from the group -NHOH, -NR22R23, where R22 and R23 are independently hydrogen or lower alkyl and -N02, and in which finally Y represents hydrogen or one of the following radicals. a) an optionally substituted lower aliphatic, lower cycloaliphatic or lower cycloaliphatic lower aliphatic group, the substituents being one or more from the group hydroxyl, lower alkoxy, optionally substituted phenyloxy, optionally substituted heterocyclyloxy, optionally substituted lower alkylthio, optionally substituted phenylthio, optionally substituted Heterocyclylthio, Mercapto, Amino, Niederalkylamino, Di-Niederalkylamino, Niederalkanoyloxy, Niederalkanoyl-amino, optionally substituted Phenyl, optionally substituted heterocyclic group, Carboxy, Carbniederalkoxy, Carbamoyl, N-Niederalkylcarbamoyl, N, N-Diniederalkyl-carbamoyl, Halogen, Cy , Thioxo, -S03H, -OSÓ3H, -S02-lower alkyl, lower alkylsulfinyl, nitro, phosphono 0 1 or-OP (ORe) (ORr), where Re is lower alkyl and Rr is optionally substituted lower alkyl, optionally substituted phenyl or heterocycyl and the substituents on the lower alkylthio group are one or more from the group halogen, hydroxy, lower alkoxy, amino, lower alkanoylamino or optionally substituted phenyl or a heterocyclic group and wherein the substituents of phenyl or the heterocyclic group are one or more from the group consisting of hydroxy, lower alkoxy, halogen, lower alkyl, halogeno lower alkyl, methanesulfonyl, lower alkylthio, amino, lower alkanoylamino, lower alkanoyloxy, carboxy, carboxy lower alkyl, sulfo or sulfo lower alkyl; b) -ORs, in which Rs denotes optionally substituted lower alkyl or lower alkanoyl or optionally substituted phenyl or a heterocyclic group, the substituents of alkyl and alkanoyl being one or more from the group halogen, hydroxy, lower alkoxy, lower alkylamino, di-lower alkylamino, amino, oxo, Lower alkanoylamino or optionally substituted phenyl or a heterocyclic group and where the substituents of phenyl or the heterocyclic group are one or more from the group hydroxyl, lower alkoxy, halogen, lower alkyl, halogen lower alkyl, methanesulfonyl, lower alkylthio, lower alkylamino, diniederalkylamino, amino, lower alkanoylamoxy, lower alkanoyl Carboxy, carboxy lower alkyl, sulfo or sulfo lower alkyl; c) -S (0) nRs, where n is 0.1 or 2; d) halogen; and e) optionally substituted phenyl or a heterocyclic group, in which the substituents are one or more from the group hydroxyl, lower alkoxy, halogen, lower alkyl, halogen-lower alkyl, methanesulfonyl, lower alkylthio, Amino, lower alkylamino, di-lower alkylamino, lower alkanoylamino, lower alkanoyloxy, carboxy, carboxy-lower alkyl, sulfo or sulfo-lower alkyl; or a pharmaceutically acceptable salt thereof. 5 2. A compound according to claim 1, wherein Y is hydrogen, ethyl or a-hydroxyethyl. 3. A compound according to claim 1, wherein Y is a-hydroxyethyl. 4. A compound according to claims 1-3, wherein Alk Clio alkylene, A represent oxygen, sulfur or S = O, Alk 'C2 alkylene and R20 amino. 5. A process for the preparation of a compound according to any one of claims 1-4, wherein Z is hydrogen, characterized in that in an inert organic solvent 15 a compound of the formula at a temperature from just above room temperature to the reflux temperature of the solvent S-T II wherein Y is as defined in claim 1, Q is phenyl or nie 30 CO II deralkyl, R "represent an ester protecting group, and T represents -CX, where X- (alk) -A- (alk ') - R2o, is cyclized, whereupon the ester protecting group is split off. 35 6. Process for the preparation of a compound of formula I. , wherein Y has the definition given in claim 1 under a), Z is hydrogen and - (Alk) -A (Alk ') - R20 is as defined in claim 1, characterized in that a compound according to the method of claim 5 which produces formula I, in which Z and - (Alk) -A- (Alk ') - R20 are as defined above and Y is hydrogen, and in the compound obtained one of the groups defined in claim 1 under a) by reaction with a introduces the appropriate electrophilic reagent. 45 7. A process for the preparation of a compound of formula I, wherein Y has the definition given in claim 1 under b) or c), Z is hydrogen and - (Alk) -A- (Alk ') - R2o as defined in claim 1 is characterized in that a compound of the formula I is prepared by the process according to claim 5, in which Z and - (Alk) -A- (Alk ') - R20 are as defined above and Y is hydrogen, and in of the compound obtained introduces one of the groups defined in claim 1 under b) or c) by reaction with a corresponding electrophilic reagent, see 8. Process for the preparation of a compound of the formula I in which Y is halogen and - (alk) -A- ( Alk ') - R20 as defined in claim 1, characterized in that a compound of the formula I is prepared by the process according to claim 5, in which Z and - (Alk) -A- (Alk') - R20 define fio as above and Y is hydrogen, and the compound obtained is halogenated accordingly. 9. A compound of formula II, wherein Y, Q, R "and T are as defined in claim 5, as a means for carrying out the method according to any one of claims 5-8. 65 10. Pharmaceutical composition containing, as active component, a compound according to one of claims 1-4 and a pharmaceutically acceptable carrier or diluent. 643 846