DK161970B - azetidinone - Google Patents

Description

in

DK 161970 B

The present invention relates to novel azetidinone derivatives of the general formulas (III) and (IIIa) which are valuable as starting materials in the preparation of novel biologically active penem derivatives of the general formula 5 o Χο, ι 10 2 wherein Z is hydrogen or an easily removable ester protecting group, and Y is (a) methoxymethoxyhydroxyethyl, in which case X is methyl, (b) formamidomethyl or 2,2-dimethyl-1,3-dioxolanyl, in which case X is all alkyl of 1-6. (c) hydroxy-substituted alkyl of 1-6 carbon atoms, in which case X is aminocyclobutyl, or (d) is hydrogen or I-hydroxyethyl, in which case X is (i) - (C ) where n is an integer from 1-6 and alkyl is lower alkyl of 1-6 carbon atoms, (ii) - (CH2) n ~ NHOH, where n is an integer from 1-6, (iii) 25 -, εΒΒ '- γΧ) 0 where n is an integer from 1-6, 35 (iv) - (CH,) -0CO (CH,) NRARB where n and m are independently 1

Λ ^ ρΠ C

or R 2 is independently hydrogen or alkyl of 1-6 carbon atoms, (v) - (CH 2) n ~ NHC (RC) = NH, where n is an integer of 1-6 and RC is in

DK 161970 B

any carbon having 1-6 carbon atoms, phenyl or

"<CV 'O

Wherein m is 1 or 2, (vi) CH 3 -CH 2 -C 10 <-OCH 3 or (vi i) carbamoyloxymethyl, or a pharmaceutically acceptable salt thereof.

The azetidinone derivatives of the invention have the general formula -

20 I

J-P (Q) 3 M

ISLAND

co ~ r "x (III)

25 V

wherein Y represents methoxymethoxyhydroxyethyl, formamidomethyl, 2,2-dimethyl-1,3-dioxoalyl, hydroxy-substituted alkyl of 1-6 carbon atoms, hydrogen or 1-hydroxyethyl, Q represents phenyl or (lower) alkyl, R "represents a readily removable ester protecting group, x represents 1 or 2, and M represents Cu (II), Pb (II) or Hg (II) when x is 2, or Ag (I) when x is 1, or the formula Y .SHgCOOCH-.

v- <3

35 I

J-N P (Q), O ^ y? 3 C02R "(I Ha)

DK 161970 B

3 wherein Y, Q and R are as defined above.

In the intermediates of formulas III and III, Q represents preferably

Cl phenyl, and R "preferably p-nitrobenzyl.

The penem derivatives of formula (I) can be prepared by a 5 or more of the reaction pathways discussed below. The various synthetic pathways can be divided into three main processes depending on the step in which the 6-substituent, namely Y, is incorporated. According to Method I, the 6-substituent is incorporated into the starting material itself, according to Method II, Y is incorporated at the end of the synthesis and according to Method III, the substituent Y is introduced midway into the synthesis. Each of the three main processes can again be varied by the method used to introduce the desired 2-substituent, namely X. In general, it is preferred to introduce the substituent Y midway into the synthesis and introduce the substituent X by acylation of the mercaptide shown below. intermediate III or III, since these methods d have been found to be the most widely applicable.

The various steps of Method I are shown in the following reaction scheme:.

Method I (variant 1) 4

DK 161970 B

Y. O.

V pr; ^ QAe II

Y-CH-CH-OAc CSI I CH3C-SNa J- N pH 7.5

u H

Y _ ^ SAc Y

r -> "S-rSAc x I CHO Γ -—> ^ -Nv 1 1 SQm O XH CO R" Λ-N OH 2 1 O 7 ^ CO 2 R "

In \ _ ^ SAc Y-, I P ^ 3 i-Τ 'SAc

ί --T MA

s) -N cl base * -> O NsT ^ o ^ L_Nx.pø3 base CO_R "2 co2r"

% '% Λ_ 0 O

"" L-r ^ SM || Il j X-C- 0 ^ "A-j- ^ SC-X ^ s? -Nx ^ I, -> 0 Y 3 0 ^ C-n \ ^ po3 CO R" 2 co2r "

Y

X ^ S \ * /) - x v V_ s; ^ | \ _x 0 CO R "deprotection J-N ^ / 2 O \ co2h X-C (= 0) - + = acylating agent MA = heavy metal salt

Method I (variant 2) 5

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Y \ - ^ Ohc 0 CSNa

Y-CH = CH-OAc CSI ^ I

- * j_ N -ϊΓΐ.5 "

o ^ H

-r - ^ - SCØ ^ __ Y "S-r ^ SC $ 23 - ^ CHO SOCl2

J-Nx "CO R" / -N \ ^ ° H

o H 2 o co2r "

Y

V _ ^ SCØJ pø ^ -r „SC03 MA

oi_i Cl oJ_n ^ p03 51 ^ C02R "co2r · 'o V O - * r 11" γ-γΞΜ x-c- © x f SC_X Δ; 0 <J- γ ^ 3> ο ^ -ΝγΡ03 C02R "C02R" 4.

Y

S /.S Y

^ \ V

.Hl / x - * rH Vx-

Q \ depreciation — N "-V

CO R "O"

2 CO 2 H

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6

In process I, a vinyl ester (Y = H or a group as defined in compound I) containing the desired 6-substituent is converted to the optionally 1-substituted 4-acetoxy-2-azetidinone by a cycloaddition reaction with chlorosulfonyl isocyanate (CSI) after -5 followed by reduction with an organic reducing agent such as sodium sulfite. The CSI reaction is conveniently 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 ° or lower and at a slightly basic pH.

After formation of the 4-acetoxy-2-azetidinone, Method I can be divided into two different pathways. Variants 1 and 2 above convert 4-acetoxy-2-azetidinone to 4-acetylthio-2-azetidinone and 4-tritylthio-2-azetidinone, respectively, by nucleophilic exchange 15 with thioacetic acid and triphenyl methylmercaptan (or a salt thereof, such as the sodium salt) ..

Next, the 4-thio-azetidinone is reacted with a giyoxylate ester HC (= O) -CO 2 R "wherein R" is a readily removable ester protecting group such as p-nitrobenzyl or trimethyl silylethyl, or with a reactive oxo derivative thereof, such as a hydrate, in an inert organic solvent (e.g., benzene, toluene, xylene or the like) and preferably at an elevated temperature (e.g., 50 ° C until most preferred reflux temperature). When a hydrate of the ester is used, the resulting water can be removed azeotropically or with molecular sieve.

The hydroxyester compound is formed as a mixture of epimers which may be optionally purified, such as by chromatography, - or used directly in the following step.

Conversion of the hydroxy ester to the corresponding chloro ester is achieved by reaction with a chlorinating agent (e.g., SO 2 Cl, POCl 2, 30 PClg, and the like) in an inert organic solvent (e.g. tetrahydrofuran, diethyl ether, methylene chloride, dioxane * similar) in the presence or absence of a base, preferably an aliphatic tertiary amine (e.g. triethylamine) or a heterocyclic tertiary amine (e.g. pyridine or collidine). The reaction is advantageously carried out at -35 a temperature of approx. -10 ° C to room temperature. The chloroester compound is obtained as a mixture of epimers which may be purified before use in the following step.

The phosphorane intermediate can be obtained by reacting the chlorine

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The ester with a suitable phosphine (preferably triphenylphosphine or a tri (lower) alkylphosphine such as triethylphosphine or tri-n-butylphosphine) in an inert organic solvent such as dimethylformamide, dimethyl sulphoxide, tetrahydrofuran, dimethoxyethane, dioxane or et al in fatty, cycloaliphatic or aromatic hydrocarbon (e.g., hexane, cyclohexane, benzene, toluene, and the like) in the presence of a base, preferably an organic tertiary amine such as triethylamine, pyridine or 2.6-1utidine . The reaction is advantageously carried out at temperatures from room temperature to the solvent to the reflux temperature of the system.

The phosphorane is converted to a heavy metal mercaptide of the formula “yZ--

15 J-N 7 (Q) 3 M

ISLAND

co7r "

1 X

III

20 or ^ SHgCOOCH3 25 ^ -N P (Q), O 3 CO 2 R

IIIa wherein Q is preferably phenyl or (lower) alkyl, x means 1 or 2, and M is Cu (II), Pb (II) or Hg (11) Λ when x is 2, or Ag (I) when x is 1. The mercaptide formation is carried out by reacting the phosphorane with a salt of Hg (11), Pb (II), Cu (II) or Ag (I) or with (methoxycarbonyl) mercury (II) acetate in a methanol-containing solution. And in the presence of an organic or inorganic base such as aniline, pyridine, collidine, 2.6-1utidine, an alkali metal carbonate, and the like. A preferred base is pyridine. The reaction can be carried out at room temperature or, if desired, with moderate cooling or heating.

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8

The anion (A) of the heavy metal salt may be any anion which provides a soluble salt in the selected solvent, e.g. NO 3 ", CH 2 COO, BF 2, F", ClO 2 -, CNO ~, etc. The mercaptide intermediate is then reacted with an acylating agent capable of introducing the X-5-C (= O) moiety. wherein X represents the desired penem-2 substituent The acylating agent (Χ-ΰ (= O) -φ) may be the acid XC (= O) -OH or a reactive functional derivative thereof, such as an acid halide (preferably oxygen). chloride) acid azide, acid anhydride, mixed acid anhydride, active ester, active thioester, etc. Acylation can be carried out in an inert solvent (e.g., a halogenated hydrocarbon such as methylene chloride, or an ether such as dioxane, tetrahydrofuran or diethyl ether) and, when an acidic derivative is used, in the presence of an acid acceptor such as a tri- (lower) alkylamine (e.g., triethylamine) or a tertiary organic base such as pyridine, collidine or 2,6-lutidine. The acylation is carried out in the presence of a suitable condensing agent, for example a carbodiimide such as Ν, Ν'-dicyclohexyl Acylation of the mercaptide can be carried out over a wide range of temperatures, but is preferably carried out from ca. -20 to + 25 ° C. After acylation, the resulting phosphorane is cyclized as described above to form the desired pen ester.

Formation of the phosphorane via the mercaptide intermediate has been found to result in a product of far better purity than that obtained in a more conventional way.

Once the carboxyl protected penem compound is formed, can.

The protective group is removed by conventional unblocking methods (e.g., hydrolysis, hydrogenation or photolysis) to form the unblocked penem compound. Removal of the p-nitrobenzyl ester can e.g. is obtained by catalytic hydrogenation in the presence of a precious metal catalyst such as palladium or rhodium, including derivatives thereof, such as oxides, hydroxides or halides, the catalyst being optionally supported on a conventional support such as carbon or diatomaceous earth.

A non-reducing aqueous or non-aqueous inert solvent such as water, ethanol, methanol, ethyl acetate, tetrahydrofuran, diethyl ether or dioxane are used. Hydrogenation can be carried out at atmospheric pressure or elevated pressure and suitably carried out at room temperature for a period of about 1 to 5 hours, depending on the solvent used and the catalyst. If during hydrogenation an equivalent weight amount of a base such as an all potassium metal or

DK 161970 B

9 alkaline earth metal hydroxide or an amine, the product can be recovered in the form of a carboxylic acid salt. Removal of the γ-trimethylsilylethyl ester, which is another valuable protecting group, is conveniently carried out by treatment with a source of fluoride ions. Other ester protecting groups 5 can be similarly removed by methods known per se.

According to another major process (Method II), the reaction sequence is as shown below:.

Process II (variant 1) DK-16A70 B 10 OAc CH- = CH-OAc CSI v I AcSNa

^ j_ N ^ 7.S

O ^ H

_-- "SAc _ ^ _ SAc _ ^ CHO SOC1 rT N \ h CO R" -N \ ^ 0H 2

O H 2 O

co2r "- ^ - SAc p0 ^ -r" SAc µα_ J L ~ C1 base -N \ ^ p03. base ° γ- 0 T.

CO2R "CO2R

ISLAND·

O II

rrSM. nfsc "x a> 0J — Ν-γΡ03 '^ 0J — N \ ^? 03 co2r" co2r "

^ Sv Y

- \ 'π. s I y-X γ \ Ί - Γ \

J v— ~ i base ^ _I X

° * Λθ, - ^ Γ Vx

deprotection _N

O \

C02H

Method II (variant 2)

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π _ ^ OAc 03CSNa CH = CH-OAc CSI ^ I -— 7 r- ^ • 2 ^ X— N pH 7/5

O ^ H

w. ^ SCØ-, ___ ^ _r ^ -SCØ ^ _—> -3 ~ CHO I S0C12

In J_m OH

"h C02R" 0 ^ Ύ C02R "

_ ^ SC03 P03 -Τ 'SC03 MA

/— N. ~~ C1 0j-N \ ^ P03 o y io2R "C ° 2R"

ISLAND

o II

- ^ SM x-c- © ^ X Δ> o ^ Ln ^ .p03 * oJ_n ^ p03 C02R "co2R" —r "\ γχ_ ^ s \ i / x —-—> i Vx ^ base J_

CO2R ° * CO2rM

-> V> depreciation J__n O \ co2h

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12

As can be seen, process II is essentially the same as process I (except that Y must be H) until the thermal cyclization step which forms the 2-substituted penem compound. However, if desired, a 6-substituent is now introduced by reacting the 2-penile compound with a suitable electrophilic reagent in an inert solvent (e.g., tetrahydrofuran, diethyl ether, dimethoxyethane, and the like) and in the presence of a strong base. . In this procedure, the 2-penem compound can be reacted in the form of the free acid (obtained by unblocking as described above) in the presence of ca. two equivalents of base, 10 or alternatively, a suitable 2-pen master can be used in the presence of approx. an equivalent base. Any ester which is inert to anion chemistry may be used (the reaction comprises base anion formation followed by reaction of the electrophilic reagent with the penic anhydride), e.g. (lower) alkyl such as methyl, ethyl, n-propyl or t-butyl, phenyl, trichlorethyl, methoxymethyl, silyl such as trimethylsilyl or t-butyldimethylsilyl, and the like. Penemasters with activated methylene groups, such as p-nitrobenzyl, are not suitable and if the 2-penemester is of this type it must first be boiled and either used as free acid or converted to a suitable ester. The particular base used is not critical and the usual strong bases such as sodium hydride, phenyllithium or butyl T-vthium are suitable. Most preferably, however, a lithium diisylamide or lithium dialkylamide such as lithium dicyclohexylamide (LDCA), 1 in thium di ethyl amide, lithium dimethylamide or lithium diisopropyl amide (LDA) is used. The electrophilic reagent is selected so that it is capable of developing the desired Y substituent by reaction with the anion and can e.g. be a halogen (e.g., Br 2, I 2), a, alkyl halide (e.g.

CH1 1) or a similar halide, such as an aliphatic, cycloaliphatic, cycloal in the fatty alkali, phenyl (1avere) alkyl, heterocyclic, heterocyclyl-thio, heterocyclyl-thio (lower) alkyl or heterocyclyl (Lower) alkyl halide, a tosylate or mesylate (e.g.

ch3ch2oso2- ^ J ^ h3, ch3ch2oso2ch3, C3 ^ so2 ^^) - so2, 35

ISLAND

OCH2CH2CH2OSO2CH3, etc.), an epoxide (e.g., / \), an episulfide

S

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13

S

(e.g., / \), an aldehyde (e.g., CH3CHO, C6H5CH2CHO), a rv ° ketone (e.g., CH3COCH3, 1J) or an ester (e.g.

CH3CH2C00CH3 or CgHgC000CH3). Representative examples of other suitable electrophilic reagents are shown below: CH2 = CH-CH2Br • i? , Br CH3CCH = CH2

Br L J-Br CH-CH-CH- i j C1 ØCH2Br HCHO ØCSCCH2Br O0 \ _ / ch2sch2ci CH3SS02CH3 00CH2C1 ØCH = CHCHO 0 ^ \] o 11 I-1 CH CCH Cl Η | k

\ ς / —C-CH-jCl, s II 2 O

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14

A particularly preferred electrophilic reagent is acetaldehyde giving rise to the hydroxyethyl-6 substituent. Introduction of the 6-substituent by this method is preferably carried out with cooling, e.g. -80 ° to 0 ° C) according to the general procedure described in Canadian Journal of Chemistry, 50 (19), 3196-3201 (1972).

After formation of the desired 2,6-penem compound, any ester protecting group may be removed as discussed above to form the deprotected product.

The third main process (Method III) is understood from the following reaction scheme:. 4th

Method IH

15

DK 161970 B

SC03 SC03

J- N Λ-N

0 H ° XB

y V_ / SCØ

base A N

O B

aite shuttle ^^ y / '\ —r'scø3

J-N

O νη <pHO CO R

V

4

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16

Y'x-X __ / SM

Y- <^ SC03 o ^ J N \ ^ P03 A-N. r-OH CO-R "Q '2

CO 2 R

11 ^ Ί v, x-c- Θ SOCl2 ψ ψ o sc-x

Y ^. ^ scø3 I

1 -N \ ^ p03 ° i ϋ C02R "C02R" Δ P03 ψ

base Y

v ^ _τ'Λ ~ ί ·> -x j y · ^ .scø. o \

JV

In deprotection co2r ·· ψ

V

MA / base j-Γ \ __ χ O \

C02H

B = ring nitrogen blocking group.

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The 4-tritylthio-2-azetidinone of method III is formed as described by method II (variant 2). The azetidinone ring nitrogen is then protected with a conventional readily removable blocking group such as triorganosilyl (e.g. trimethylsilyl or t-butyldimethylsilyl), methoxymethyl, methoxyethoxymethyl, tetrahydropyranyl, and the like.

Insertion of the desired Y substituent into the 1-position of the azetidinone is then achieved by reacting an appropriate electrophilic reagent with the N-protected azetidinone in the presence of a strong base (reaction conditions as described above for Process II). At 10 this point, the process separates into two paths depending on the time of azetidinone unblocking.

The N-protected intermediate by conventional methods (e.g. acidic hydrolysis) and then converted to the 2,6-penem compound via ester formation, chlorination of the hydroxyester, conversion of the chloroester into a phosphorane, conversion of the phosphorane to a heavy metal mercaptide, acylation of the mercaptide with XC (= 0} - +, thermal cyclization of the resulting phosphorane to form the 2,6-penemester and removal of the carboxyl protecting group. The reaction conditions for these steps are as described in connection with Method II 20 (variant 2).

In preparing the 2-penem or 2,6-penem compounds according to the above methods, free functional groups in the substituents X or Y which do not participate in the reaction can be temporarily protected in a manner known per se, such as free amino groups by acylation. , Tritylation or silylation, free hydroxyl groups, e.g. by etherification or esterification, mercapto groups by esterification, and free carboxyl or sulfo groups, e.g. by esterification, including silylation. Once the reaction has taken place, these groups can, if desired, be released individually or together in a manner known per se.

Furthermore, in the compounds of formula I, it is possible to functionally modify the 2- and / or 2,6-substituents below or at the end of the reactions in a manner known per se to obtain other substituents which fall within the scope of the invention. . For example, carbonyl groups can be reduced to all alcohol groups, unsaturated aliphatic. -35 groups can be halogenated, amino groups can be alkylated or acylated, nitro groups can be converted to hydroxyamino and amino groups, hydroxyl groups can be etherified or esterified, etc.

The free penic acids can be converted into pharmaceutically acceptable salts

DK 161970 B

18 thereof or to easily removable esters thereof (especially physiologically cleavable esters). Salts can be formed by reacting the free acid with a stoichiometric amount of a suitable non-toxic acid or base in an inert solvent followed by recovery of the desired salt, such as lyophilization or precipitation. Esters (especially physiologically cleavable esters) can be prepared analogously to the preparation of the corresponding esters of penicillins and cephalosporins. Resulting mixtures of isomers can be separated into the individual isomers in a manner known per se. Mixtures of diastereomeric isomers may e.g. is separated by 10 fractional crystallization, adsorption chromatography (column or thin layer chromatography) or other suitable separation methods. Resulting racemates can be cleaved into the antipodes in the usual manner, e.g. by forming a mixture of diastereomeric salts with optically active salt-forming reagents, separation of the diastereomeric salts, conversion of the salts to the free compounds, or by fractional crystallization from optically active solvents.

The provided free penic acids and pharmaceutically acceptable salts and physiologically cleavable esters thereof have been found to be potent broad-spectrum antibacterial agents valuable for treatment.

20 of infectious diseases in animals and humans, caused by both gram-negative and gram-positive organisms. The compounds are also valuable as nutritional supplements for animal feed and as agents for the treatment of mastitis in cattle.

The following examples illustrate the preparation of azetinone derivatives 25 of the invention and their use as starting materials. All temperatures are in ° C. For the sake of simplicity, some examples have used some abbreviations. The definitions of the less obvious abbreviations are as follows: 4,

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19 CSI chlorosulfonyl isocyanate cap. ether petroleum ether kp. boiling point n.m.r. Nuclear Magnetic Resonance 5 hours ether diethyl ether (unless otherwise stated)

Cell in tea trademark for diatomaceous earth from Johns-Manville

Products Corporation psi pounds per square inch 10 r.t. room temperature PNB p-nitrobenzyl m.p. melting point LAH lithium aluminum hydride n-BuLi n-butyllithium MIBK methyl isobutyl ketone

A C

Tr -C (C6H5) 3

Me CH3-THF tetrahydrofuran 20 Ph phenyl DMF dimethyl formamide TEA triethylamine PNBG p-nitrobenzylglyoxylate THP tetrahydropyranyl TFA tri fluoroacetic acid HMPT (or HMPA) hexamethylphosphoric triamide EtOAc ethyl acetate DMSO dimethyl sul foxide Ac Ac CH3 CO

Py pyridine LDA 1 in thium diisopropyl amide

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20

Example 1 1- (p-n itrobenzyloxycarbonylmethyl tri phenylphosphoranyl) -4- (silver mercapidyl) -2-azetidinone

CO? PMB

OAc STr _ / TrSH - (

_L NaOMe * i— N

H

1 - 1

A methanol (90 ml) suspension of tri phenyl methyl mercaptan (13.8 g, 0.05 mmol) was degassed for 0.5 hours with a stream of nitrogen. The mixture was cooled at 0 ° and sodium hydride (2.4 g, 0.05 mole, 50% oil dispersion) was added portionwise. The resulting solution was stirred for 5 minutes and 4-acetoxyazetidinone (7.7 g, 0.059 mol) in water (55 ml) was added rapidly. Precipitation of 4-triphenylmethylmercaptoazetidinone (2) occurred immediately. The mixture was stirred for 4 hours at room temperature. The solid was filtered off, washed with water and dissolved in methylene chloride. The methylene chloride solution was washed with dilute HCl, water, aqueous sodium bicarbonate, water and brine and dried over MgSO 4 (89.8%, mp 146.5 - 147.5 ° C).

Analysis for 33 gNOS:

Calculated: C: 76.49, H: 5.54, N: 4.05, S: 9.28, Found: C: 7.54, H: 5.60, N: 4.00, S: 9 , 36th

Δ (ppm, CDCl 3) 7.60 - 7.10 (15H, m, H-trityl), 4.62 (1H, bs, NH), 4.40 (1H, dd, J 4 J4_3 ci $ = 5, H-4), 3.24 (1H, ddd, Jgm = 15, 3-4 cis = 5 'd3-NH = 1.8> H-3)' 2.81 (1H 'ddd' dgem = 15, J3-4 trans = 3, ° 'J3-NH = 1,2> H "3 ^ vc = o (CHCV 1760>' 'nH 30 3340.

sir Γ _ / ^ Tr r- ^ STl

1 -1 * in OH + J - C C OH

35 Y ° Y

CO PNB CO PNB

2 i -

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21

Hydrated p-nitrobenzylglyoxylate (4.54 g, 0.02 mole) and azetidinone 2 (6.90, 0.02 mole) for reflux are evaporated in benzene through a Dean Stark capacitor loaded with 3A molecular sieves for 24 hours. Additional glyoxylate (2 x 454 mg, 2 mmol) was added with a reflux period (18 hours) after each addition. The mixture was diluted with ether, washed with 5% aqueous HCl, water, aqueous 5% NaHCO 3, water and brine. Dry over MgSO4 (12 g, quantitative). A small fraction of the epimeric mixture was separated on a sieve gel plate (Cl 2 Clg ether 6: 4).

Isomer A: Rf = 0.87, m.p. 170.5 - 171.5 °.

10 & (ppm, CDCl 3) 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, Cl 2 -PNB), 4.75 (1H, s, HC-O), 4.37 ( IH, dd, J3.4 trans - 3, J3_4 ci $ = 4, H-3), 2.83 (1H, dd, Jgem - 16, J4_3 ds = 4, H-4), 2.10 (1H, dd,

Jgem = 16 'J4-3 trans = 3' ^ J'42 <b · 5 · '0H> · ^ o <CHCV 15 1770, 1760 (shoulder), "202 1525, i / QH 3475.

Isomer B: Rf = 0.75, mp 152 - 153 °. δ (ppm, CDCl 3), 8.13 (2H, d, J = 9, Hm aromatic), 7.47 (2H, d, J = 9, H aromatic), 7.40 - 7.00 (15H, m , trityl), 5.30 (3H, s, CH2-PNB, HC-O), 4.45 (1H, t, J = 3.5, H-4), 2.90 - 2.70 (2H, 20 AB portion of ABX, H-4), 1.55 (bs, OH). v ^ 0 (CHC13) 1767, 1755 (shoulder), ^ 1525, i / QH 3500.

. STr / STr rf- .1 ° ^ _K rf 25 J -, 1 OH pyridi "^» γα 1o2PNB Χ ™ Β 3 1 30 A cold (-15 °) THF (150 ml, dried over molecular sieves) solution of azetidinone 3 ( 12 g, 21.7 mmol) were treated with pyridine (1.9 g, 24.1 mmol, 1.94 ml) and dropwise with thionyl chloride (2.86 g, 24 mmol, 1.88 ml) under a nitrogen atmosphere. The precipitate was filtered off and washed with benzene Evaporation 35 of the solvent gave a residue which was taken up in benzene and treated with activated charcoal (11.7 g, 94% crystallized from chloroform).

δ (ppm, CDCl 3) 8.17 (2H, d, J = 8, Hm aromatic), 7.67 - 7.00

DK 161970 B

22 (17H, m, Ho aromatic, Tr-H), 5.80 (s, HC-Cl), 5.37, 5.33 (2s, HC-Cl, CH2-PNB), 4.81 (1H, m, H-4), 3.27 - 2.40 (2H, m, H-3).

Vo (KBr filn) 1785 '1770 1525 · 5' STr / STr - [Φ3Ρ_ —in J-2,6-Lutidine QJ—

CO PNB CO PNB

2 2 10 4 5

A THF (100 ml, distilled over LAH) solution of chlorazetidinone 4 (11.6 g, 20.2 mmol) was treated with tri phenylphosphine (7.86 g, 30.0 15 mmol) and 2,6-lutidine (2 , 36 g, 2.56 ml, 22.0 mmol). The mixture was refluxed for 72 hours. The precipitate was filtered off and washed with ether.

The organic solution was washed with 2% aqueous HCl and 5% aqueous bicarbonate and dried over MgSO4. Evaporation of the solvent gave a residue which was purified through sieve in cake pad (200 g). The desired phosphorane was eluted with 30, 40 and 50% ether-benzene (11.4 g, 70.4%, mp 201-202 °).

Analysis for C4gH4oN₂ ° 5SP:

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.

25 i / c = Q (CHCl3) 1740, v phosphorane (1620, 1610), VHO2 1525.

r-ί ^ ΤΓ * 9Ν ° 3 [-fSA9 pyridine 30 CO PNB co pus 2 2 si 4-Trityl mercaptoazetidinone 5 (1.6 g, 2 mmol) was dissolved in CH 2 Cl 2 -35 (20 ml) and the solvent was evaporated at 55 -60 °. Phosphoran 5 at 55-60 ° was dissolved in preheated (55-60 °) methanol (32 ml). Immediately after obtaining a methanol in the so-called solution of 6, it was treated with a preheated (55-60 °) mixture of methanolic 0.15 M silver nitrate solution

DK 161970 B

23 (16 mL, 1.2 equivalents) and pyridine (174 mg, 178 μΐ, 2.2 mmol, 1.1 equivalents). The heating bath was then removed immediately. The mixture was stirred at room temperature for 2 hours and at 0 ° C for 1 hour. The silver mercaptide 6 was filtered off, washed twice with cold (0 °) methanol and three times 5 with ether. (1.12 g, 84.5%, m.p. 130-135, decomp.) V (CHCl3 -) 1795, 1725 (shoulder), v phosphorane (1620, 1605), c-o o ΊΜ) 2 1530.

Example 2 1- (p-ni trobenzyloxycarbonylmethyl tri-phenylphosphoranyl) -4- (silver-mercaptidyl) -2-azetidinone-2-scoch 3 K CO

A-Nv CT ^ C = FPh O ^ C = PPh I 3 I 3 COOPN8

COOPNB

6 2 - 25

A solution of phosphoran 7 (1.796 g, 3.00 mmol) in chloroform (3 ml) was diluted with methanol (90 ml), cooled at 0 ° C under nitrogen atmosphere and treated successively with silver nitrate (0.51 g, 3.0 mmol). ) and potassium carbonate (0.33 g, 2.4 mmol). The reaction mixture 30 (protected from light) was stirred at 0 ° C for 15 minutes, then the cooling bath was removed and stirring was continued for 3 hours. The reaction mixture was cooled to -10 ° C, stirred for 1 hour and filtered; the silver mercaptide was washed successively with cold methanol and ether; 1.91 g, m.p. 138-145 ° C, decomp. 96%. IR (nujol) cm -1: 1748, 1620 and 1605. An analytical sample 35 was obtained by preparative TLC (ethyl acetate); mp. 140-5 ° C for C30H24N2 ° 5SPA9:

Calculated: C: 54.31, H: 3.65, N: 4.22, S: 4.83,

Found: C: 54.11, H: 3.48, N: 3.92, S: 4.62.

DK 161970 B

24

Example 3 1- (p-ni trobenzyloxycarbonylmethyl tri phenylphosphoranyl) -4- (silver-mercaptidyl) -2-azetidinone A. Use of aniline as a base 5 · SCOCH _ / SAg -SJ Aniline, AgN'O -j J_N MeOH ^ - N.

0 ^ C = PPh ^ 0 c = PPh3

COOPNB COOPNB

10 7 __ 6 ·

A solution of phosphorane 7 (1.8 g, 3.0 mmol) of chloroform (4 ml) was diluted with methanol (90 ml), cooled to -15 ° C under nitrogen atmosphere and successively treated with silver nitrate (.0.56 g, 3.3 mmol) and aniline (1.5 ml, 16.5 mmol). The reaction mixture (protected from light) was stirred at -15 ° C for 0.5 hours, then the cooling bath was removed and stirring was continued for 24 hours. The reaction mixture was cooled to -10 ° C and stirred for 1 hour before being filtered; the silver mercaptide was washed successively with cold methanol and ether; 1.55 g, m.p. 114-5 °, decomp.

77.9%. IR (nujol) cm identical to the compound of Example 2.

Silver 1- (paranitrobenzyl-2β-triphenylptiosphoranylidene-2β-acetate) -2-25-azetidinone-4-thiolate B. Use of 4-dimethylaminopyridine (DMAP) as a base SCOCH. / SAg _ / 3 Ag NO / DMAP | - [30 0J - '' ^> * 3 CH2C12 / CH3 ™ "0j—« γ-ΡΦ,

X2PNB “C02MB

A solution of the above-mentioned S-acetylphosphorane (17.96 g, 30 mmol) in methanol and dichloromethane (1: 2, 450 ml) was purified with nitrogen (5-10 minutes), cooled to 5 ° C and treated successively with silver nitrate (5.35 g, 31.5 mmol) and 4-dimethylaminopyridine (3.85 g, 31.5

DK 161970 B

25 mmol). The ice bath was removed and the solution was refluxed vigorously for 2 hours, and then stirred at room temperature for 1 hour. The colored reaction mixture was treated with charcoal, filtered and evaporated. The residue was redissolved in the minimum amount of dichloromethane and added dropwise with stirring to cold methanol (300 ml). The precipitated silver salt was collected by filtration, washed with ether and dried; 18.1 g (91%); IR (CHCl3) ν '. 1745 (C = 0 of β-lactam) and 1607 cm -1 (C = 0 of ester).

Silver-1- (paranitrobenzyl-2β-triphenylphosphoranylidene-2 "acetate) -2-15-azetidinone-4-thiolate C. Using diazabicycloundecene (DBU) as a base .SCOCH ^ SAg-r 3 AgNO -s 'J— N Ρφ DBU' «« Ο »i_N Ρφ

cr o 'J

CO PUB CO PNB

The above-mentioned S-acetylphosphorane (36.0 g, 0.060 mol) was dissolved in methylene chloride 120 ml. The solvent was evaporated to obtain an oil. The resulting oily residue was dissolved in hot (35 ° C) methanol (240 ml) and treated quickly with a methanol in silver (420 ml) solution of silver nitrate (10.68 g, 0.0628 mol). The resulting solution (or suspension) was stirred at room temperature for 5 minutes, cooled (ice bath) and a DBU (8.96 ml, 0.060 mol). * Solution in methanol (20 ml) was added over a period of 5 minutes. The mixture was stirred for 5 minutes. The solid was filtered off, washed once with cold (0 ° C) methanol and ether and dried under vacuum; 37.0 g (93%); IR (nujoT '35 mull) γ (c = o) and 1600 cm -1 (phosphorane). max 5 - 26

DK 161970 B

$ beer-1- (paranitrobenzyl) -2-triphenylphosphoranylidene-2ll acetate) -2- -acetidinone-4-thiolate D. Use of pyrrolidine as a base SCOCH _ -S '_Pyrrol idi n_ |

µ AqNO) -N

rJ- ^ J 3 Ό "^^ PPh 0 ^ C = PPh I 3

L COOPNB

COOPNB

10

To a cold (0 ° C) solution of 4-acetylthio-1- (paranitrobenzyl-2 "triphenylphosphoranylidene-2" acetate) -2-azetidinone (0.60 g, 1.0 mmol) in CH (2 mL) was added MeOH (4 mL), a solution of AgNO 3 in MeOH (0.14N, 7.86 mL, 1.1 mmol), and a solution of pyrrolidine (0.92 mL, 1.1 mmol) ) in MeOH (2 ml). The cooling bath was removed and the reaction mixture was stirred for 1.75 hours, cooled to -10 ° C, stirred for 0.25 hours and filtered.

The solid was washed with cold MeOH and dried in vacuo; 0.548 g, m.p.

115 ° C, 82.4%. IR (nujol) i /: 1755 (C = 0) and 1600 cm -1 (aromatic).

ίΠαΧ 20

Example 4

Mercury (II) - [2'-tri phenylphosphoranylidene-2'-acetate] -2-azetidinone-4-thiolate STr 25 i-S Hg (OAc) 2 2 N \ fPPh3

CO ^ pNB

30 1 s, "g

C02PNB

ri

DK 161970 B

27

A solution of I (2.4 g, 3 mmol) in dichloroethane (15 ml) was cooled to 5 ° C and treated with a solution of mercury acetate (0.525 g, 1.65 mmol) dissolved in methanol (15 ml). After stirring at 5 ° C for 2 hours, the solvent was evaporated and the residue was redissolved in dichloromethane 5 and washed with cold water. After drying (MgSO4) and treating with charcoal, the organic solution was evaporated to give a foam which crystallized by trituration in ether. Yield: 1.73 g (91%), m.p. 123-127 ° C. IR (CHCl13) 1745 cm' [[ε β-lactam) 1608 cm'1 (phenyl).

10 15

Example 5 2-Methylpenem-3-p-nitrobenzyl-carboxyl at (from mercaptide intermediate) 20 y5 2Hg 2CH-2COCl

PPK

._N PPh pyridine J 3 3 cr y I CO PNØ 25 co2PNB 2 II 111

A solution of II (262 mg, 0.2 mmol), acetyl chloride (35 mg, 0.44 30 mmol) and 2 drops of pyridine in 10 ml of dichloromethane was stirred at 5 ° C for 1 hour. The precipitated mercuric chloride was then filtered off and the filtrate was washed successively with cold dilute hydrochloric acid, sodium hydroxide and finally brine. The organic solution was subjected to a stream of hydrogen sulfide for 2 minutes at 5 ° C and stirred at that temperature for another 35 minutes to precipitate the last traces of mercury salts.

Some charcoal was added to the black mixture, which was then filtered through a pad of Cel in tea. Evaporation of the clear filtrate left 193 mg (80.7%) of III as a foaming material. IR (CHCl

DK 161970 B

28 lactam) 1692 ("sCQCHg) 1620 (phenyl).

'jCOCH __ ^ s.

π. —-—- ΓΤ y <*> 5. 0J-v3 oJ_ Λ

0 IN CO PNB

co2pnb

2 III 2 IV

10 Phosphoran III (75 mg, 0.126 mmol) in toluene (10 ml) is refluxed over a period of 2.5 hours under a nitrogen atmosphere. Evaporation of the solvent and purification of the residue gave a crystalline derivative (25 mg, 63%), whose physical and spectral data were in full agreement with the title product.

Product IV may, if desired, be subjected to catalytic hydrogenation (30% Pd on Cel in tea) to prepare the corresponding 3-carboxylic acid product.

Example 6 2-Aminomethylpenem-3-carboxylic acid (from mereaptide intermediate)

QAg SCOCH N

_f ClCOCH ^ -p 1 J

y N CH2 Cl2 j — N.

30 o y = PPh3 I h3

COOPNB * · COOPNB

1 2 35 A solution of silver mercaptide 1 (1.25 g, 1.99 mmol) in dichloromethane (15 ml) kept under nitrogen atmosphere was cooled at 0 ° C and treated dropwise with a 2M solution of azidoacetyl chloride in dichloromethane (1.13 ml, 2.26 mmol). The reaction mixture was stirred

DK 161970 B

29 at 0 ° C for 1 hour; the cooling bath was removed and stirring was continued for 5 hours. The reaction mixture was filtered over a Celite pad and the solids were washed with dichloromethane (35 ml). The filtrate and washings were combined, washed with sodium bicarbonate solution and water, dried over anhydrous sodium sulfate and concentrated in vacuo to an orange syrup, which was purified by column chromatography (30 g silica gel 60, eluate; ether-2% ethyl acetate (200 ml), ether -6% ethyl acetate (200 ml) and ether-20% ethyl acetate (500 ml), fraction size: 10 ml). Combination and evaporation of fractions 49-80 gave a yellow powder; 0.73 g, m.p. 61-70 °, 60.8%.

_ ^ coc «2" 3 pi -i—. I> -CH2N3 ._µ Toluene - cf N: = pph 0 \

In "3 COOPNB

COOPNB

15 2 3

A solution of phosphorane 2 (0.593 g, 0.93 mmol) in toluene (20 ml) was heated at 105 ° C for 1 hour, cooled to 23 ° C and concentrated to a semi-crystalline compound which was purified by column chromatography (12 20 g silica gel 60, eluate: benzene (100 ml), benzene-2% ether (100 ml) and benzene-4% ether; fraction size: 10 ml). Combining and evaporating fractions 18-26 gave a yellow syrup which crystallized on standing; 0.18 g, m.p. 127-8 ° C, 53.7%. NMR (CDCl3), δ 8.22 (2H, d, JHq Η | η = 8.8 Hz, H0 of p-nitrobenzyl), 7.60 (2H, d, Jm = 8.8 Hz, Hm of p-nitrobenzyl), 5.71 (1H, dd, J5j6 ds - 3.6'hz, J5j6 trans = 2.1 Hz, H-5), 5.33 (2H, center of ABq, Jg ^ = 14 Of p-nitrobenzyl), 4.58 (2H, center of ABq, Ja ^ = 15.0 Hz, CH2on C-2), 3.88 (1H, dd, ° 6.5 cis 3 · 6 Hz 'Jgen,' 16: 5 Hz-H'6 c1s> 3'55 (1H 'dd' J6.5 trans - 2.1 Hz, 0 - 16.5 Hz, H-6 trans). IR ( Nujol) cm · 1: 2115 and 2090 (N +) »1780 (c = o of) 8-lactam) and 1685 (c = o of p-nitrobenzyl ester). An analytical sample was obtained by preparative TLC; mp 427-8 ° C for C 14 H 11 N 5 ° 5S:

Calculated: C: 46.54, H: 3.07, N: 19.37, S: 8.87,

Found: C: 46.43, H: 3.08, N: 19.37, S: 8.90.

35

DK 161970 B

30

I r \ »1 30% Pd / celite, | \ _- γη N'H

Yes' -thp, e-, srTV ^ i ^ rc! 2

COOPNB COOH

2 i

To a solution of penem 3 (0.18 g, 0.5 mmol) in tetrahydrofuran (6 ml) was added successively ether (6 ml), water (6 ml) and 30% pal 1a-dium-on-Celite (0.18 g). The reaction mixture was hydrogenated below 30 psi at 23 ° C for 2.5 hours and filtered over Celite pad; the pad was washed with water and the filtrate and washings were combined, washed with ether-THF mixture and lyophilized to give 30 mg, 30%, of compound 4.

[Water and ether-insoluble compound were dissolved in chloroform and the organic solution was washed with water and dried over anhydrous sodium sulfate. Evaporation of the solvent under reduced pressure gave 77 mg (42.8%) of starting material 3].

NMR (DMSO d-6) δ: 5.7 (dd, J IR (nujol) cm -1: 1775 (c = 0 of / Mactam) and 1615, 1585.

UV AmaxH2Omµ: {e = 2320) and 307 (e = 2685).

Title 4 product was also obtained from intermediate 3 by the following route: 25 -H Pd / D.E. -rv

/) - CH N -2 --- ν 'Λ-CH NB

2 3 THF, Ether, -N - (/ 1 l O H_0 \

COOPNB 2 COOH

3 2 30

A

To a solution of penem 3 (2.4 g, 6.89 mmol) in tetrahydrofuran-ether-water mixture (1: 1: 1, 165 ml) was added 30% palladium-on-diatomaceous earth (4, 8 g). The reaction mixture was hydrogenated below 45 psi at 23 ° C for 2.5 hours and filtered over Celite pad. The filtrate and washings were combined, washed twice with ether, centrifuged and filtered several times to give a clear solution which was lyophilized; 0.622 g, 45%. The crystallization of the compound

DK 161970 B

31 was induced by the addition of water (0.8 ml); the suspension was centrifuged and the water removed leaving an orange solid.

This solid was washed twice with water and a slightly yellowish solid was obtained after drying: 0.273 mg, 19.8%. UV + max H2 O: 307 (6 = 4318) and 257 (e = 2650). Some crude starting material (1.2 g, 50%) was recovered. The compound (50 mg) can also be purified by column chromatography [Sephadex G10, column size 1.6 x 100 cm, flow rate 10 ml / hour, eluent: distilled water, fraction volume: 1.5 ml, detector: refractive index]. UV + axH 2 O: 307 (6 = 3597) and 255 (6 = 10 2424).

The stability of the compound in aqueous solution was checked by: UV: 6 hours 307 (6 = 3545) and 255 (e = 2773) 21 hours 307 (6 = 3467) and 255 (6 = 2411) 28 hours 307 (e = 3337) and 254 (6 = 2398) 15 46 hours 307 (6 = 3259) and 254 (e = 2398) 70 hours 307 (6 = 3076) 94 hours 307 (e = 2842) 170 hours 307 (6 = 1900)

A sample of compound 4 was maintained at 23 ° C for 3 days and UV 20 was performed: UV AmaxH 2 O: 307 (e = 3055) and 255 (e = 2008).

Compound 4 was converted as described below into two additional 2-penem derivatives.

-r'Sy m NaHCO ^ H., 0 _ rT ^ \ - CH.:N=C/H2 25 _J / -CH2NH3 -Γ 'OJ - "- / * CH3 \, 0cp CH ^ -OEt VoAa0 1 - 30

A suspension of compound 4 (50 mg, 0.251 nmol) in distilled water (0.5 ml) was treated with 1 equivalent of sodium bicarbonate (21 mg) followed by addition of ethyl acetimidate (21.8 mg, 0.024 ml). The reaction mixture was stirred at 23 ° C for 20 minutes and lyophilized to give 52 mg of a yellow solid. NMR (D 6 O) δ: 5.7 (m, H-5) and 2.23 (e.g., CH 3 of amidine). IR (KBr) cm ":: 1772 (c = 0 of β-lactam). UV Ama) (D₂O m / i: 305 (e = 3116) and 253 (e = 2525). Compound 5 was placed on a column (Sephadex G10, column size: 1.6 ml)

DK 161970 B

32 and lyophilization of appropriate fractions gave 23 mg 45% of slightly yellowish powder. UV AmaxH 2 O m / i: 303 (e = 2960) and 248 (e = 2885).

5! JXWC

jr λ Λα «1 £ - 10

A suspension of compound 4 (50 mg, 0.25 mmol) in distilled water (0.5 ml) was treated with sodium bicarbonate (21 mg, 0.25 mmol) and stirred for 1.5 hours before the addition (2 minutes) of mixture of sodium bicarbonate (126 mg, 1.5 mmol) and ethyl formimidate, hydrochloride (164 mg, 1.5 mmol). The reaction mixture was stirred for 10 minutes at 23 ° C and lyophilized to give an orange powder. UV

AmaxH2 ° m: 304 = 2300> · 20

Example 7 6-Ethyl-2-aminomethylpenem-3-carboxylic acid (cis- and trans -isomers)

\ Λ-Γ \ cB NH

25 1} ~ CH2tm2 ° 9 2 2

t! ^ \: o2H ^ C02H

a. Silver cis- and trans-3-ethyl-1- (p-nitrobenzyl-2'-triphenylphosphoriclidene-2'-acetate) -2-azetidinone-4-thiolates

A solution of cis- and trans-3-ethyl-1- (p-nitrobenzyl-2'-pho-phoranylidene-2β-acetate) -4-acetylthio-2-azetidinones (1.88 g, 3.0 mmol Example 1, Structure 7) in chloroform (4 ml) was diluted with methanol (90 ml), cooled to 0 ° and successively treated with finely powdered silver nitrate (0.51 g, 3.0 mmol) and potassium carbonate (0 , 33 g, 2.4 mmol). The mixture was stirred vigorously for 15 minutes at 0 °, 3 hours at room temperature and 1 hour at -10 ° C. The precipitated silver mercaptide was collected by filtration, washed with methanol and with

DK 161970 B

33 ether and dried in vacuo. The title product was obtained as a gray solid, m.p. 112-135 ° d «^ Q = Q 1750, 1620, 1605.

b. Cis- and trans-3-ethyl-1- (p-nitrobenzyl-2β-phosphorane, yliden-2β-acetate) -4-azidoacetyl thio-2-azetidinones

A solution of the above-mentioned crude mercaptide (1.31 g, 2 mmol) in dichloromethane (15 ml) was cooled to 0 ° and treated, in a nitrogen atmosphere, with a 2M solution of azidoacetyl chloride in dichloromethane (1.13 ml, 2.26 mmol). The mixture was stirred at 0 ° for 1 hour and at room temperature for 5 hours. The insoluble silver salts were removed by filtration over Celite and washed with dichloromethane. The combined filtrates were washed with dilute sodium bicarbonate solution and water, dried and concentrated. The oily residue was purified by column chromatography over sieve cake! (35 g), eluting with ether-ethyl acetate. The relevant 15 fractions were concentrated to form a mixture of cis- and trans-acylated compounds as a semi-solid; 0.62 mg. v (CDCl3); 2105, 1760, 1690, 1621 cm -1.

Cis and trans-p-nitrobenzyl-2-azidomethyl-6-ethylpenem-3-carboxylates

A solution of the above-mentioned crude phosphorane (0.60 g) in toluene (30 ml) was kept at 105 ° for 1 hour, cooled and concentrated, leaving an oily residue which was purified by column chromatography over silica gel (20 g). eluting with increasing ratios of ether in benzene. The relevant fractions were concentrated to form both the cis and trans isomers.

Cis isomer: S (ppm, CDCl 3): 8.25 (2H, d, J = 8.8, H0 of para-nitrobenzyl), 7.65 (2H, d, Hm), 5.93 (1H, d, J = 4.1, H-5), 5.38 (2H, AB quartet, J = 14.0, benzyl), 4.68 (2H, AB quartet, J - 15.0, 2-N3) , 3.4 (1H, m, H-6), 2.0 (2H, m, CH 2 CH 3), 1.1 (3 H, t, J =%, ch 2 CH 3).

Trans isomer: 6 (ppm, CDCl 3): 8.18 (2H, d, J = 8.8, Ho), 7.59 (2H, d, Hm), 5.52 (1H, d, J = 1.4, H-5), 5.33 (2H, AB quartet, J = 14.0, benzyl), 4.58 (2H, AB quartet, J = 15.0, CH 2 -N3), 3.7 (1H, dt, J = 1.4, J = 7.4, H-6), 1.9 (2H, m, CH 2 CH 3), 1.1 (3 H, t, J = 7.4, CH 2 CH 3).

DK 161970 B

34 d. Trans-2-aminomethyl-6-ethylpenem-3-carboxylic acid

A mixture of the above trans-p-nitrobenzyl ester (0.20 g, 0.5 mmol), THF (6 ml), ether (6 ml), water (12 ml) and 30% palladium-on-Celite (0 , 20 g) was reduced at 23 ° for 2.5 hours at an initial hydrogen pressure of 30 psi. The catalyst was removed by filtration over Cel in tea and washed with water. The combined filtrates were washed with ether-THF and lyophilized to give the crude trans acid (12 mg). Chromatography over a column of Sephadex G-10, eluting with water, afforded the pure trans acid (6 mg) as a hygroscopic powder, v 1775, 1615 cm 2. Amax = 306 (e = 3465). δ (ppm, D 2 O-DMSO): 5.40 (1H, d, J = 2.0, H-5), 2.0 (2H, m, CH 2 CH 3), 1.1 (3H, t, J = 7 , 4, CH 2 CH 3).

* e. Cis-2-Anrinomethyl-6-Ethylpenem-3-Carboxylic Acid Reduction of the cis-p-nitrobenzyl ester as described above in connection with the transester gave the cis acid as a yellow hygroscopic powder (13%) ι / ς = 0 1775, 1615 cm-1. Amax 304 (6 = 3563). δ (ppm, D 2 -DMSO): 5.75 (1H, d, J = 4.0, H-5), 2.0 (2H, m, CH 2 CH 3), 1.1 (3H, t, J = 7.4 , CH2CH3).

Example 8

Cis and trans-6-acetoxymethyl-2-aminomethylpenem-3-carboxylic acid A-τ "Λ

AcO I Λ- CH_NH

25 J_N ^ // 2

ISLAND

co2h a) 3-acetoxymethyl-4-tritylthio-2-azetidinones (cis and trans isomers) A solution of a mixture of cis- and trans-4-acetoxy-3-acetoxy-methyl-2-azetidinone ( 4.7 g, 25 mmol) (Example 2, <structure 26) in water (200 ml) was rapidly added to a vigorously stirred solution of sodium triphenyl methyl mercaptide (from tri phenyl methyl mercaptan, 55.2 g; and sodium hydride, 9 , 6 g, in methanol, 300 ml). The mixture was stirred at room temperature for 4 hours and the solids were collected by filtration, washed with water and dissolved in dichloromethane. The solution was washed with dilute hydrochloric acid, water, aqueous sodium bicarbonate and water, dried and concentrated, leaving 85% of a solid used as

DK 161970 B

35 such in the next attempt.

b) Cis- and trans-3-acetoxymethyl-1- (p-nitrobenzyl-2β-hydroxy-2β-acetate) -4-trityl thio-2-azetidinones A solution of the aforementioned azetidinone (8.0 g, 20 mmol) and p-nitrobenzylglyoxylate (4.54 g, 20 mmol) for back-cooling are added in benzene (100 ml) through a Dean-Stark water separator loaded with 3A molecular sieves.

After 24 hours, a second portion of p-nitrobenzylglyoxylate (4.54 g) was added and reflux continued for another 24 hours. The mixture was diluted with ether, washed with 5% aqueous hydrochloric acid, water, aqueous 5% sodium bicarbonate and water. Drying and concentration left 100% of the crude isomeric mixture as an oil.

c) Cis- and trans-3-acetoxymethyl-1-p-nitrobenzyl-2'-chloro-2'-acetate) -4-tritylthio-2-azetidinones

A solution of azetidinones from step b (12.2 g, 20 mmol) and pyridine (1.9 g, 24 mmol) in dried THF (150 ml) was cooled to -15 ° and treated dropwise with thionyl chloride (2.86 g, 24 mmol) under nitrogen atmosphere. The mixture was stirred for 45 minutes at -15 °, the precipitate removed by filtration and washed with benzene, and the filtrates concentrated, leaving a semi-solid (95%).

d) Cis and trans-3-acetoxymethyl-1- (p-nitrobenzyl-2β-triphenylphosphoranylidene-2β-acetate) -4-tritylthio-2-azetidinones A mixture of azetidinones from step c (12.6 g, 20 mmol), triphenylphosphine (7.8 g, 30 mmol) and 2,6-lutidine (2.6 ml, 22 mmol) in THF (100 ml) were heated at reflux for 80 hours. The insoluble material was removed by filtration and washed with ether. The filtrates were washed with 2% aqueous hydrochloric acid, 5% aqueous sodium bicarbonate and water, dried and concentrated. The residue was dissolved in benzene, filtered slowly through a pad of silica gel (250 g) and the pad eluted with increasing ether ratio of benzene. Concentration of the relevant fractions gave a mixture of the title compounds (65%). vc = Q 1740, * 'c = P $ 3 1620, 1610, ^ 1525 cm "1.

E) Silver cis and trans 3-acetoxymethyl-1- (p-nitrobenzyl-2β-triphenyl-phosphoranylidene-2β-acetate) -2-azetidinone-4-thiolates

The crude azetidinones from step d (8.5 g, 10 mmol) were dissolved in hot

DK 161970 B

36 methanol (55-60 °). A hot solution (55-60 °) of silver nitrate (2.04 g, 12 mmol) and pyridine (0.87 g, 11 mmol) in methanol (80 ml) was added. The mixture was allowed to cool to room temperature for 2 hours and stirred for an additional 1 hour at 0 °. The silver mercaptide was collected by filtration, washed with ice-cold methanol and then with ether (5.7 g, 82%, melting during decomposition). v 1745, 1740, 1625 cm'1.

f) Cis and trans-3-acetoxymethyl-4-azidoacetylthio-1- (p-nitrobenzyl-V-tri-phenylphosphoranylidene-2'-acetate) -2-azetidone Nons The silver mercaptide mentioned above (from step e, 1.4 g, 2 mmol) in dichloromethane (15 ml) treated as described in Example 28 with azidoacetyl chloride (2.3 mmol) gave 0.78 g of a yellow powder.

g) Cis and trans-6-acetoxymethyl-2-azidomethylpenem-3-carboxylic acid p-nitrobenzyl esters

A solution of the above-mentioned crude phosphorane (0.70 mg) in toluene (35 ml) was kept at 105 ° for 1 hour, cooled and concentrated, leaving an oil which was purified by chromatography over silica gel (25 g), eluted with increasing ratio of ether in benzene.

The relevant fractions were concentrated to form the cis and trans isomers of the title product.

Cis isomers: 8 (ppm, CDCl 3): 8.5 - 7.5 (4H, aromatic), 5.67 (1H, d, J = 5, H-5), 5.31 (2H, AB quartet) , CH2-benzyl), 4.50 (2H, AB quartet, CH2N3), 4.33 (2H, d, AcOCH2), 4.26 (1H, dt, H-6), 2.0 (3H, s , CH3).

Trans isomers: 8 (ppm, CDCl 3): 8.5 - 7.5 · (4H-, aromatic), 5.62 (1H, d, J = 2, H-5), 5.33 (2H, AB) quartet, CH 2 -benzyl), 4.40 (1H, dt, H-6), 4.50 (2H, AB quartet, CH 2), 4.27 (2H, d, * AcOCH 2), 2.0 (3H , s, CH 3).

30 a.

37

DK 1619 7 O B

Example 9 r-rV ^ / i y -p (o— «ζ) ^

'CO H

5 '(_ ^ SA <3 _ 10 θΰ ^ ΡΦ3 + C1COCH2CH2Cl V ΡΦ3 C02PNB co2pnb

x II III

A solution of I (1.1 g, 1.6 mmol) and II (0.16 ml, 1.6 mmol) in methylene chloride (30 ml) was cooled on an ice bath and treated dropwise with 1M solution of pyridine in methylene chloride ( 1.7 ml, 1.7 mmol).

The resulting reaction mixture was stirred at room temperature for 1 hour and then filtered over Cel in tea and washed with methylene chloride. The filtrate and washings were combined and washed successively with 1N HCl (5 ml), water (5 ml), 1M NaHCO 3 (5 ml) and brine, then dried (MgSO 4) and evaporated in vacuo to give III 900 mg (87 %) as an amorphous solid. It was used in the next step without further purification. IR (CHCl3) 1755, 1690 cm -1. NMR (CDCl 3) δ 8.22 (2H, d, J = 9 Hz), 7.55 (15H, m), 6.72 (2H, d, J = 9 Hz), 5.7 (1H, m) ), 5.0 (2H, 2s), 3.55 (2H, 2s), 2.8 (4H, m).

- f '^ Y ^ CH 2 Cl 1 + (> —O) --- * · 0 ^ -' "Ύ * ΡΦ3 30 C02Pro, 0 2 III IV 0J-Ν- ^ ΡΦ3 CO PNB 2

35 V

A mixture of III (1.3 g, 2 mmol) and IV (0.65 ml, 3 mmol) was heated at 80 ° C for 4 hours. The reaction mixture was diluted with methylene chloride (10 ml) and washed with water (2 x 5 ml). That

DK 161970 B

38 organic layers were dried (MgSO 4) and evaporated in vacuo to give V, 1.4 g (90%) as an amorphous solid. It was used in the next step without further purification. IR (CHCl13) 1755, 1690 cm "*.

NMR (CDCl3) δ 8.25 (2H, d, J = 9 Hz), 7.55 (15H, m), 6.8 (2H, 5 -d, J - 9 Hz), 5.7 (1H, m), 5.1 (2H, 2s), 4.72 (2H, dq, 0 = 12 Hz, J = 6 Hz), 2.6 (4H, m), 1.4 (6H, s), 1 , 28 (6H, s).

, _- S (0-O.

rf & 2 - ► cT Ν \ ^ Φ3

10 '/ v Q

CO PiTB I-f \ V.

r i y -

, r CO PNB

v 2

WE

15

A solution of V (1.6 g, 2.06 mmol) in toluene (60 ml) was heated at reflux for 5 hours.

The solvent was evaporated in vacuo and the residual oil was chromatographed on silica gel column (30 g). Elution with benzene 20 followed by ether first removed unpolarized material to give ethyl acetate VI, 620 mg (62%) as a white solid, m.p. 83-4 ° C from ether.

IR (CHCl3) 1790, 1710 cm -1. NMR: (CDCl3) δ 8.2 (2H, d, J = 9 Hz), 7.6 (2H, d, J = 9 Hz), 7.5 (2H, s), 5.65 (1H, dd , Jtran $ = 4 Hz,.

Jcis = 2 Hz)> 5'22 (2H> 2s)> 4> 75 (2H> dtl 'J = 12 Hz, J = 6 Hz), 3.85 (1H, dd, Jgem = 15 Hz, Jtrans = 4 Hz), 3.5 (1H, dd, Jgm = 15 Hz> Jcis = 2 Hz} '2.8' 3.3 (2H> 1.4 (6H; s> '1.28 (6H> s)) · So cJ — uf

CO PNB CO H

2 4 2

VI VII

To a solution of VI (200 mg, 0.4 mmol) in tetrahydrofuran (8 ~ 35 ml) and ether (4 ml) was added sodium bicarbonate (34 mg, 0.4 mmol), water (4 ml) and 30% Pd / Celite (200 mg) followed by hydrogenation for 2 hours at 40 psi. The mixture was filtered and the layers separated. The aqueous phase was cooled after washing out with methylene chloride (2 x 39)

DK 161970 B

5 ml), with ice, was acidified with 1N HCl (1 ml) and extracted with chloroform (5 x 5 ml). The organic extracts were dried (MgSO4) and evaporated in vacuo to give VII, 76 mg (52%) as an oil. IR (CHCl13) 1790, 1710 cm "1. NMR (CDCl3) δ 9.5 (1H, ws), δ 5.65 (1H, dd, Jtrans = 4 Hz, Jcis = 2 Hz), 4.72 (2H , i.e., J = 12 Hz, J = 6 Hz), 4.2 - 5.1 (2H, m), 3.4 - 4.1 (2H, m), 2.7 - 3.4 (2H, m), 1.35 (6H, s), 1.25 (6H, s).

Example 10 s

10 I

I // N? (Oc h) j — N 2 b 2 CO H 2 15 _ / SAg p p I + cic (ch2) 3p (oc2h5) 2 —- ►

LpnB

I Y

20 1 1 cf Ν \ | ^ ΡΦ3 3 CO PNB - 2

To a cooled (ice-bath) mixture of 1 (1.324 g, 2 mmol) and 2 (0.54 g, 2.2 mmol, crude) in (15 ml) was added dropwise 1M solution of pyridine / CH 2 Cl 2 (2, 2 ml, 2.2 mmol). The mixture was stirred at room temperature for 1 hour and filtered over Celite. The filtrate was washed successively with 0.5N HCl, HgO, 0.5M NaHCO3 and brine. It was dried (MgSO4) and filtered over Celite charcoal to give evaporation to dryness of 0.9 g of an oil. The oil was chromatographed on 30 SiOg (10% HgO) and eluted with ethyl acetate to give 0.5 g of 3. NMR & (ppm, CDCl3) 7.0 - 8.4 (m, 19H), 4.8 * 5, 8 (3H, m), 4.1 (4H, q), 3.3 - 4.2 (2H, m), 2.7 (2H, m), 1.9 (2H, m), 1.3 (6H, t).

35

DK 161970 B

40 IO - * - ► O ^ -Ν'γΡΦ3 CO PNB c, CO PNB _4 10 3 (0.4 g, 0.52 mmol) in toluene (35 ml) to reflux for 4 hours and evaporate to dryness to form of an oil containing 3, 4 and 0 ^ Ρ = Ο. It was chromatographed on SiO₂ (10% H₂O) and eluted with EtOAc to give 0.1 g of pure 4, followed by 0.15 g of 3 and 4. NMR δ (ppm, CDClg), 8.3 (2H, d), 7.67 (2H, d), 5.7 (H, q), 5.33 (2H, d), 4.2 (4H, q), 3.83 (H, q) ), 3.4 (H, q), 2.9 (2H, m), 1.9 (2H, m), 1.3 (6H, t). IR (pure) 1790 cm' ((--lactam) 1710 cm "1 (ester).

pfs (OEt) 2 ___— v 20 Yr- N ^ / CO PNB - \ 9 2 Y (OEt) 2 CT \ co2h 25 5

A mixture of 4 (0.1 g, 0.207 mmol), 30% Pd / Celite (0.1 g) and NaHCO 3 (17 mg, 0.207 mmol) in THF (10 ml), ether (5 ml) and water ( 5 ml) was hydrogenated at an initial pressure of 40 psi for 2 hours. The product was filtered over Celite and the layers separated. The basic aqueous layer was washed well with ethyl acetate and acidified with 1N HCl.

It was extracted with Cf C and dried (MgSO4). The Cf ^ Cl ^ solution was evaporated to give 48 mg of 5 (66.5%). IR spectrum 35 & 1790 (β-lactam) 1700 (-iso-0Η).

41

DK 161970 B

Example 11 RR. Preparation of Silver 3- (Γ-parane itrobenzyldi oxycarbonyl-17-ethyl) -1- (paranotro-benzyl-2ll-triphen, ylphosphoran, ylidene-2ll-acetate) -2-azetidinone-4-5 thiolate CO 2PNB o pnb i_ysc * 3 _ι 'ιΥ5 * 9 10 oPv / 3 k CC ^ PNB co ^ pnb 15 "Isomer B" (l'R, 3S, 4R and l'S, 3R, 4S) -3- (1'-paranitrobenzylcarbonyl dioxy) -Γ-Ethyl) -1- (paranitrobenzyl-2 "-tri phenylphosphoranylidene-2" acetate) - 4-trithio-2-azetidinone (1.02 g, 1 mmol) was first dissolved in CH 2 Cl 2 (3 ml) and diluted with warm (55 ° C) MeOH (20 ml). The hot solution 20 was first treated with pyridine (120 ml, 117 mg, 1.48 mmol) and a hot (55 ° C) 0.15 m methanolic silver nitrate solution (8 ml, 1.2 mmol).

The mixture was stirred at room temperature for 15 minutes, then at 0 ° C for 2 hours. It was then concentrated to a 10% solution on rotary evaporator (no bath). The mercaptide was filtered and washed twice with cold (-15 ° C) methanol and three times with ether. (917 mg, 100%). ir (nujol mull) 1 /: 1745 (C = O), 1600 (phosphorane) and 1517 cm 2 (NO 2).

"Isomer C" Silver 3- (Γ-paranitrobenzyldioxycarbonyl-Γ-ethyl) -1- (paranitro benzyl -2 "-tri phenylphosphoranylidene-2" -triphenylphosphoranylidene-2 "acetate) -2-azetidinone-4-thiolate , "Isomer C", was prepared as described above for "Isomer B"; ir (nujol): 1745 (C = O) and <1 ΓΠαΧ 1600 cm -1 (phosphorane).

"Isomer D"

A solution of Isomer D of 3- (1'-p-nitrobenzyl carbonyl dioxy-Γ -ethyl) -1- (p-nitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -4- 35

DK 161970 B

42-Tritylhio-2-azetidinone (145 mg, 0.142 mmol) was prepared by first dissolving it in (5 ml), removing CH 2 Cl 2 at 55 ° -60 ° C and adding warm MeOH (4 ml). To the above solution was added a warm solution of AgNOg in MeOH (0.15 m, 1.14 ml, 0.17 mmol, 1.2 5 'equiv), followed by pyridine (14 μΐ, 0.17 mmol, 1). 2 equiv.). The silver mercaptide immediately began to precipitate. The mixture was stirred for 2 hours at room temperature and for 1 hour at 0 ° C. The mercaptide was collected by filtration and washed with ice-cold MeOH and ether to yield 99 mg (0.11 mmol, 78%) of title compound as a brownish solid: ir (nujol) in: 1750 cm 1 (s, C = 0).

SS. Preparation of (TR, 3S, 4R and rs, 3R, 4S) -Silver-3- (rh, ydroxy-r-ethyl) -1-) - paranitrobenzyl-2 "tri-phenylphosphoranylidene-2" acetate) Azetidinone-4-thiolate (Isomer B)

'OH? H

20 w./-V3

T CO PNB

CO 2 PNB 2 25 A solution1 of (1'R, 3S, 4R and 1'S, 3R, 4S) -3- (1'-hydroxy-r-ethyl) -1- (paranitrobenzyl-2 "-tri phenylphosphoranyl in the -2" acetate) - 4-Chrythylthio-2-azetidinone (Ig, 1.19 mmol) in MeOH (10 mL), treated with pyridine (124 μΐ, 121.3 mg, 1.53 mmol) and at 10 ° C with a 0.15 m solution of silver nitrate in MeOH (15 mL, 2.25 mmol) or 30 until precipitation of silver mercaptide ceased). The mixture was stirred for 1 hour and concentrated in the rotary evaporator (no bath) to a concentration of ca. 10%. The solvent was filtered off. The cake was washed once with MeOH and 3 times with ether and pumped under high vacuum (954 mg, 100%). ir (nujol mull) wm: 3500-3400 35 (0-H), 1752 (C = 0) 1595 (phosphorane) and 1525 cm -1 (NO2).

The crystalline material was first dissolved in CHgCl2.

DK 161970 B

43 TT. Preparation of (1'R, 3R, 4R and 1xS, 3S, 4S) 4-Acetylthio-3- (lp-ni trobenzyldi oxycarbonyl-1'-ethyl) -1 - (pn in trobenzyl - 211 - tri-phenylphosphorane. (2-azetidinone (Isomer D). oco2pnb oco2pnb SSAg CH ^ COCl-Pyr ^^ oBy · 3 CH ^

"CO PNB

CO 2 NB 2 10

To a stirred solution of silver 3- (1'-paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azetidinone-4-thiolate (isomer D) (85 mg, 0.095 mmol) in CH 2 Cl 2 (5 ml) containing pyridine (30 µl, -0.37;

Fisher) was added at 0-5 ° C CH 2 COCl (20 µl, 0.28 mmol) and the mixture was stirred at 0-5 ° C for 30 minutes. The precipitate which formed was filtered and washed with CH 2 Cl 2. The filtrate and washings were combined, washed successively with brine, diluted HCl, saturated NaHCO 3 and then brine, dried (Na 2 O 4) and evaporated to give 75 mg (0.091 mmol, 95% crude yield) of title compound -20 late as a syrup: m mr (CDCl13) δ: 2.33 (s, -SOCOCH ^). IR (pure) v: 1750 (/ Mactam, ester), 1695 (thioester), 1520 and 1350 cnf *

iUoX

(-N02).

UU. Preparation of (rR, 5R, 6R and rS, 5S, 6S) cis-p-nitrobenzyl-2-.

25-methyl-6- (Γ-p-nitrobenzyldioxycarbonylmethyl-penem-3-carboxylate (Isomer D)

OCO.PNB - OCOjPNS

JL .SAc

-Γ -toluene- "I WH

30 XA Ρφ Δ 3 o '3 \

In 4 CO PNB

co2pnb 2

A solution of the above-mentioned acetylthioazetidinone (74 mg, 0.09 mmol) in toluene (30 ml) was heated under reflux under N 2 atmosphere for 7 hours. After evaporation of the solvent, the residue was purified by hplc (SiO 2; eluent, benzene: ether = 3: 1) to give a yield of 24 mg (0.044 mmol, yield 49%) of the penem ester as 44

DK 161970 B

a syrup. (Note: this oil could be crystallized from THF ether or CH 2 ether: 1 Hmr (CDCl 3) δ: 1.40 (3H, d, J = 6.5 Hz, 1'-CH 3), 2.38 (3H, s, 2-CH 3), 4.07 (1H, dd, Jg g = 4 Hz, Jg j = 9 Hz, 6-H), 5.05 - 5.30 - 5.34 - 5.59 (2H, AB type, 3-CO 2 O-Ar), 5 * 30 (2H, s, 1'-OCO 5 -5-Ar), 5.1 - 5.6 (1H, m, 1'-H), 5.68 (1H, d, Jg g = 4 Hz, 5-H), 7.49 - 7.64 - 8.18 - 8.33 (4H, A2'B2 ', 1'-aromatic Hs), * 7.53 7.68 - 8.18 - 8.33 (4H, A2'B2 ', 3-aromatic Hs). IR (pure) i /: 1780 (? -Lactam), 1750 (-0C0, 1710 (ester), 1520 and 1350 cm -1 (-N (r)).

10 VV. Preparation of (rR, 5R, 6R and r $, 5S, $ 6) potassium and sodium 6- (r-hydroxyethyl) -2-methylpenem-3-carboxylate (Isomer D),

OCO PNB ° H

XL S H ^ / Pd-Celite -I ^ * S \ 15 n> C “3 THF-ethsr-H ^ O * J_N.

0 \, b

A solution of the above penem ester (24 mg, 0.044 20 mmol) in THF (5 ml) was mixed with ether (10 ml), H 2 O (5 ml), phosphate buffer (1.00 ml, 0.05 molar). pH 7.00: Fisher) and 30% Pd - Celite (50 mg, Engelhard). This mixture was hydrogenated at 35 psi for 21.5 hours at room temperature. After removal of the catalyst (over Celite), the aqueous layer was separated, washed with ether and lyophilized to give 12 mg of the title with the mixture of sodium

and potassium salts as a white powder: x Hmr (D 2 O) δ>: 1.23 (3H, d, J

= 6 Hz, 1'-CH 3), 2.27 (3H, s, 2-CH 3), 3.85 (1H, dd, Jg g * 4 Hz,

Jg j = 9 Hz, 6-H), 4.3 (1H, m, Γ-H) and 5.65 ppm (1H, d, 0g g = 4 Hz, 5-H). IR (Nujol) ν: 1755 (β-lactam) and 1570 cm -1 (-CO-).

UV (HoO) λ__ν: 297 (e 2300, calculated as K salt), 258 (e 1900,

l illaX

calculated as K salt). This material was identical to a sample of title compound prepared by aldol condensation of acetaldehyde with the dianion of 2-methylpenem-3-carboxylic acid. (x Hmr, IR, UV).

35

DK 161970 B

45

Example 12 (rS, 5R, 6S and 1'R, 5S, 6R) 6- (r-Hydroxy-r-ethyl) ~ 2-methylpenem-3-carboxylic acid (isomer C) 5 'oh ΫΥ CO2

Method A: oco2pnb oco2pnb? Co2pnb Λγ 9_Arfssc —- CO PNB CO PNB 2 2 2

OH

Ύγ

CO H

Method B:

OCO PNB 0C02PNB OCO ^ NB

. YCY A ^ SAg AA ^ -N J-µ A-N ^ XSi ^ 4- o XSi ^ l- 0 SY + - 4.

OCO PNB OCO PNB QCO ^ NB

A2 A / sac / \ A-ac I _. I -► -► 1 ► J— N ..OH J N, Ρφ γ — Nv 0 ^ 3

H CO PNB CO PNB

2 ^

DK 161970 B

46

Method A

1) (1'S, 3S, 4R and 1'R, 3R, 4S) 4-acetylthio-3- (r-paranitrobenzyl-dioxycarbonyl-1'-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphine) phoranylidene-2 "acetate) -2-azetidinone (isomer C)

OCO-PNB "PC02PNB

CH ^ COCl AV * ΡΦ3 ”w

T CO PNB

C02PNB ^ 2

A cold (ice-MeOH bath) solution of (1'S, 3S, 4R and rR, 3R, 4S) silver-3- (1'-parani trobenzyl-di oxycarbonyl-1'-ethyl) -1- (paranitrobenzyl-15) 2 "-Triphenylphosphoranylidene-2" acetate) -2-azetidinone-4-thiolate (isomer C) (1.14 g, 1.30 mmol) in CH 2 Cl 2 (60 mL) was treated with pyridine (0.6 mL, 0.74 mmol) and dropwise with acetyl chloride (236 mg, 0.213 ml, 3.00 mmol). The reaction mixture was stirred for 1 hour at -15 ° C. The precipitate was filtered and washed with ether. The filtrate was washed with 2% aqueous HCl, water, 2% aqueous NaHCO 3, water and brine, and dried (MgSO 4). The residue obtained after solvent evaporation was triturated in ether (895 mg, 83.7%, mp 184-5 ° C, decomp.). IR (CHCL ·) v: 1755, 1695 (C = O), 1620 and 1605 cm -1 (phosphorane).

Analysis for C ^ l ^ g ^O₂Si:

Calculated: C: 61.38, H: 4.42, N: 5.11, S:. 3.90,

Found: C: 61.26, H: 4.49, N: 4.88, S: 4.26.

2) (1S, 5R, 6S and 1R, 5S, 6R) paranitrobenzyl-2-methyl-6- (1 H -parnititrobenzyldioxycarbonyl-1'-ethyl) -penem-3-carboxylate (isomeric acid) C)

Jt

OCOjPHB f ° 2PNB

A __ <SA <: Δ Α | _Γ ^ \ Π Ρφ 0J— 35 cr ψ3 o \

C02PNB C02PNB

DK 161970 B

47

A solution of (1'S, 3S, 4R and 1R, 3R, 4S) 4-acetylthio-3- (1 '- paranitrobenzyldioxycarbonyl-1'-ethyl) -1- (paranitrobenzyl-2 "-tri-phenylphosphoranylidene-2 (acetate) -2-azetidinone (isomer C) (855 mg, 1.04 mmol) in toluene (60 ml) was heated at reflux for 4.5 hours. The residue obtained after concentration of the solution was passed through a silica gel (10 g) column (1% ether in benzene) to give the pure title compound (393 mg, 69.6%), mp 157-158 ° C (CHCl₃ - ether). IR (CHCl3) v: 1785, 1745, 1710 (C = O) and 1525 cm -1 (NO2). x Hmr (CDCl 3) δ: 8.30 - 7.2 (8H, m, H-aromatic), 5.46 (1H, d, J = 1.8, H-5), 5.40 - 5.0 (5H, m, z CH2-PNB and Η-Γ), 3.95 (1H, dd, J = 1.8, J = 5.4, H-6), 2.35 (3H, s, CH3) and 1.43 ppm (3H, d, J = 5.4, CH 3).

Analysis for ^ 24 ^ 21 ^ 3 ^ 10 ^:

Calculated: C: 53.04, H: 3.89, N: 7.73, Found: C: 52.76, H: 3.86, N: 7.69.

3) (rs, 5R, 6S and TR, 5S, 6R) 6- (1 H -hydroxy-1,1-eth, yl) -2-methylpenem-3-carboxylic acid (isomer C) oco2pnb 99

CC ^ PNB CO 2 H

25

A mixture made of (rs, 5R, 6S and rR, 5S, 6R) paranitro-benzyl-2-methyl-6- (1'-paranotrobenzyl di oxycarbonyl-1'-ethyl) -penem-3-carboxylate (206 mg , 0.379 mmol), THF-ether-HgO (30 mL, 40 mL, 20 mL), a 0.05M pH 7 buffer solution (7.64 mL, 0.382 mmol), and 30% Pd-on-Celite (500 mg) was hydrogenated at 42 psi H2 on a Parr shaker for 16 hours. The catalyst was filtered and washed with water. The aqueous phase was washed with ether (3 times), acidified portionwise with cold 1% aqueous HCl to pH 2.5, and extracted with ethyl acetate (15 x 20 mL) between each HCl addition. The ethyl acetate extracts were combined and washed with brine (3 x 30 ml).

Evaporation of the solvent and trituration of the residue with ether afforded the title compound (57 mg, 65.6%). IR (KBr) 1 /: 3580-3300 (0-H), 1755 and 1660 cm -1 (C = 0). UV (EtOH) \ 311 (£ 6538),

nlcLX

48

DK 161970 B

262 (<r 3672). mr (DMSO-d 6) S: 5.57 (1H, d, J = 1.7, H-5), 4.02 (1H, m, Η-Γ), 3.75 (1H, dd, J = 1.7, J = 3.5, H-6), 2.23 (3H, s, CHg) and 1.23 ppm (3H, d, CH ^).

Method B

1) Silver (rs, 3S, 4R and TR, 3R, 4S) 1- (t-butyldimethylsilyl) -3- (r - paranitrobenzyldioxycarbonyl-1'-ethyl) -2-azetidinone-4-thiolate (isomer C) - 10

OCO-PNB OCO PNB

Γΐ / 3οΦ3 'NiBu t: Bu 15

Isomer C of r- (t-butyldimethylsilyl) -3- (1'-paranitrobenzyldioxy-carbonyl-r-ethyl) -4-tritylthio-2-azetidinone (1 g, 143 mmol) was dissolved by stirring in hot (40 ° C) methanol (12 ml). A solution of silver nitrate (0.59 g) in methanol (12 ml) was added followed by pyridine (0.13 ml). The mixture was stirred vigorously for 1 hour at room temperature and for 2 hours at 0 ° C. The solid silver mercaptide was collected by filtration and washed with ether, 352 mg (46%). IR ν: 1735 cm * ((C = 0).

2 - (1'S, 3S, 4R and 1R, 3R, 4S) 4-Acetylthio-1- (t-but, yl dimethylsilyl-3- (Γ-parani trobenzyldi oxycarbonyl-Γ-ethyl) -2- azetidi non (isomer C) 3Q oco2pnb oco2pnb X __ / SAg χ A_ ^ SAc O \ si 0 ^ Si ^ tBu ^ tBu

To a solution of isomer C of silver 1- (t-butyldimethylsilyl) -3- (1'-paranitrobenzyldioxycarbonyl-Γ-ethyl) -2-azetidinone-4-thiolate (880 mg) in dichloromethane (40 ml) 0 ° C was added pyridine 49

DK 161970 B

(0.57 ml) followed, dropwise, by acetyl chloride (0.49 ml). The mixture was stirred for 0.5 h at 0 °, the solids removed by filtration and the filtrates diluted with ether, washed with aqueous hydrochloric acid (2%), water, sodium bicarbonate (2%) and brine, dried 5 and concentrated to leave the title material. one like an oil. (610 mg). x Hmr (CDCl 3) 5: 8.2 and 7.48 (4H, 2d, aromatic), 5.40 (1H, d, J = 2.2, H-4), 5.2 (2H, s, benzyl) , 5.3 - 4.9 (1H, m, Η-Γ), 3.42 (1H, dd, J = 2, H-3), 2.32 (3H, s, CH 3), 1.40 ( 3H, d, J = 6.5, CH 3), 0.95 (9H, s, t-Bu), and 0.2 ppm (6H, 0¾).

3) rs, 3S, 4R and rR, 3R, 4S) 4-Acetylthio-3- (r-paranitrobenzyl dioxycarbonyl-Γ-ethyl) -2-azetidinone (isomer C) oco2pnb oco2pnb A __ / SAc AZ / SAc

i — N / Me j — N

σ 2 c / \ H

VtBu 1 2 3 4 5 6 7 8 9 10 11 35

Isomer C of the above-mentioned S-acetyl-Nt-butylmethyl-silyl-2-azetidinone derivative (1.4 g) was dissolved in a mixture of TFA (0.5 ml), 3 water (0.5 ml), methanol (3 ml) and dichloromethane (2 ml) and stirred 4 at room temperature for 48 hours. The solution was diluted with water 5 (100 ml) and extracted with dichloromethane (4 x 20 ml). The combined organic extracts were washed with sodium bicarbonate (2%) and 7 brine, dried and concentrated leaving the crude title compound as an oil. Purification was carried out by chromatography over 9 screens in cage! (30 g), eluting with 5% ether in benzene; (650 mg).

10

Crystallization from benzene gave a white solid. x Hmr (CDCl 3) S: 11 8.15 and 7.45 (4H, 2d, aromatic), 6.18 (1H, NH), 5.19 (2H, s, benzyl), 5.05 (2H, m , H-4 and Η-Γ), 3.35 (1H, dd * J = 2.5, 4.5, H-3), 2.34 (3H, s, CH 3), and 1.42 ppm ( 3H, d, J = 6.5, CH 3). IR v ·. 1780, 1750, 1695 cm -1 (OO)

ind A

5 - 50

DK 1 β 197 0 B

4) (1'S, 3S, 4R and 1'R, 3R, 4S) 4-acetyl ylthio-3- (r-paranitrobenzyl dioxycarbonyl-Γ-ethyl) -1- (paranitrobenzyl-2 "-hydroxy-2" - acetate) - 2-azetidinones (epimers at C-2 ") (isomer C)

OCCUPNB 0C02PNB

X _ \ ^ _v Λ_γ5Α <:

o> -%, T

10 CO PNB

'2

A mixture of isomer C of 4-acetylthio-3- (1'-paranitrobenzyl dioxycarbonyl-1'-ethyl) -2-azetidinone (750 mg), paranitrobenzylgyoxylate hydrate (525 mg) and benzene (50 ml) was heated under reflux for 3 days over a Dean and Stark apparatus loaded with 3A molecule s.

A second portion of glyoxylate (52 mg) was added and reflux continued for a further 2 days. The mixture was diluted with ether, washed with hydrochloric acid (2%), water, sodium bicarbonate (2%) and water, dried and concentrated, leaving an oily residue (975 mg). Chromatography on silica gel eluting with benzene ether (85 = 15) gave the pure title compounds. x Hmr (CDCl 3) 5: 8.25 - 6.75 (8H, m, aromatic), 5.30 and 5.12 (4H, 2s, benzyler) 5.05 - 4.70 (1H, H-2 ") ), 4.45 - 4.35 (1H, 2d, H-4), 4.50 - 4.10 (1H, m, H-1 '), 3.30 (1H, m, H-2) and 1.25 ppm (3H, 2d, CH 3) 1

DK 161970 B

51 5) (1'S, 3S, 4R and 17R ^ 3R, 4S) 4-acetylthio-3- (1 H -paranitrobenzyl dioxycarbonyl-Γ-ethyl) -1- (paranitrobenzyl) -2 "triphenylphosphorus. ylidene-2ll-acetate) -2-azetidinone (isomer C) oco2pnb oco2? m

Al / SAC 50d2 Φ / tf — n \ / oh o ^

CO PNB CO PNB

2 2 10

OCO PNB

j / sac / -N Y ^ 3 15 co2pnb

Isomer C of 4-acetylthio-3- (r-paranitrobenzyldioxycarbonyl-r-ethyl) -1- (paranitrobenzyl-2 "-hydroxy-2" acetate) -2-azetidinone (577 20 mg, 1 mmol) was dissolved in anhydrous THF (10 ml) and pyridine (95 mg, 1.2 mmol) were added to the solution. The solution was cooled to 0 ° and thionyl chloride (143 mg, 1.2 mmol) was added slowly. The mixture was stirred for 30 minutes at 0 °, diluted with a small amount of ether and the insoluble salts removed by filtration and washed with ether.

The combined filtrates were concentrated to give the crude mixture of epimers of the C-2 "chlorine compound. It was dissolved in THF (20 ml), triphenylphosphine (314 mg, 1.2 mmol), and 2,6-lutidine (1). 29 mg (1.2 mmol) was added and the solution was stirred at 45 ° C for 4 days. The solids were removed by filtration, washed with benzene and the combined 30 filtrates concentrated, leaving an oil whose spectral characteristics and tic behavior was identical to a sample of the title compound prepared by acylation of the corresponding silver thiolate.

The desired penem product can be prepared by reacting the title compound according to the method of steps 2 and 3 of Example 35 (Method A).

DK 161970 B

52

Example 13 (1'R, 5R, 6S and 1S> 5S, 6R) 6- (1'-hydroxy-r-ethyl) -2-methylpenem-3-carboxylic acid (isomer B)

5 OH

TT

Yo H '^ 2

Method A

oco2pnb oco2pnb oco ^ pnb xk / x_ / SSc Y., _ r-s Τι - I -> T T *, <Ττφ3 o ^ Vj ΤβΤ ^

CO PNB CO PNB C02PNB

2 2

OH

_r ^ S \ λ-CHy

J 0 * N ^ V

C02H

Method B

oh oh "" "" T- / SAg 1) TMS / TEA -YSAc "i-" ΡΦ, 2> AcC1 * J— L .Ρφ * 0 3 pyridine & 3 C02PNB 3) H30 + C02PNB 4

OH OH

Λ-rVc CO PNB CO J * 2 z

DK 161970 B

53

Method A

1) (1'R, 3S, 4R and 1'S, 3R, 4S) 4-acetylthio-3- (1 H -paranitrobenzyl-dioxyearbonyl-1'-ethyl) -1- (paranitrobenzyl-2 "-tri phenylphos - 5 (phoranylidene-2 "acetate) -2-azetidinone (isomer B)

OCO ^ PNB OCO PNB

J 2 SAg J She S ^ "'·· -S AcCl ^' '· | -j 10 ο ^ -ΝΎ · ΡΦ3 C5Hs" "3

CO PNB CO PNB

2 2

A solution of (1'R, 3S, 4R and 1 / S, 3R, 4S) silver-3- (1'-paranitro-benzyl in oxyearbonyl-ethyl)-par-paran in trobenzyl-2 "-triphenylphospho-ranylidene -2 "acetate) -2-azetidinone-4-thiolate (isomer B) (917 mg, 1.03 mmol) in CH 2 Cl 2 (20 mL) was treated at -15 ° C (ice-MeOH bath) with pyridine (242 il, 247 mg, 3.13 mmol) and dropwise with acetyl chloride (142 µl, 157 mg, 2.0 mmol). The mixture was stirred for 15 minutes at -15 ° C and the solid filtered and washed with ether. The organic solution was washed with 2% aqueous HCl, 2% aqueous NaHCO 3, water and brine and dried over MgSO 4. After solvent evaporation, the residue obtained crystallized from ether (710 mg, 80%, snip. 183-185 ° C. IR (CHClC) v: 1755, 1695 (C = 0), 1620, 1605 γ (ΠαΧ (phosphorane) and 1625 cm "1 (NO ^).

2) (rR, 5R, 6S and TS, 5R, 6R) paranetrobenzyl-2-methyl-6- (Γ-paranitrobenzyldioxyearbonyl-1 H -ethyl) -penem-3-carboxylate (isomer B)

OCO PNB OCO-PNB

J SAc I 2 30 ArT _. Λ-τν », oj_N Ρφ3 Δ 4 J-i 3

CO PNB CO PNB

2 z 1

A solution of (1'R, 3S, 4R and rS, 3R, 4S) 4-acetylthio-3- (1'-parani trobenzyldi oxyearbonyl-1'-ethyl) -1- (parani trobenzyl-2 "-tri phe -Nylphosphoranylidene-2 "acetate) -2-azetidinone (650 mg, 0.791 mmol) for back-cooling is evaporated in toluene for 7 hours. The solvent evaporation

DK 161970 B

54 g of concentrated solution were passed through a silica gel column (10 times its weight), and title compound (0.5% ether-benzene to 2% ether-benzene) was obtained as a white solid; 329 mg, 77%, snip.

134-135 ° C (CiyrL-ether). IR (CHCl3) ν + χ: 1785, 1745, 1705 δ (C = O) and 1525 cmn * (NO₂). iHmr (CDCl3) 8: 8.20 (2H, d, Ho aromatic), 7.60 (2H, d, Hm aromatic), 5.55 (1H, d, J = 1.5, Hs), 5.5 - 4.75 (5H, m, 2CH2-PNB, Η-Γ), 3.86 (1H, dd, J = 7.8, J = 1.5, H-6), 2.38 (3H, s, CH ) and 1.50 ppm (3H, d, J = 6.3, CH 3).

Analysis for C24H2A ° 10S: 10 Calculated: C: 53.04, H: 3.89, N: 7.73, S: 5.90,

Found: C: 53.05, H: 3.98, N: 7.63, S: 6.02.

3) (1 / R, 5R, 6S and rs, 5S, 6R) 6- (1 H -hydroxy-1 H -ethyl) -2-methylpenem-3-carboxylic acid (isomer B)

OCO PNB 9H

Jx, _ ^ Sx h2 -1 ^ SV_ fQ- “· 'CO.PNB 2 20 2

A mixture of (1'R, 5R, 6S and 1'S, 5S, 6R) paranitrobenzyl-2-methyl-6- (r-paranitrobenzyldioxycarbonyl-1'-ethyl) -penem-3-carb oxylate (isomer B) ( 65 mg, 0.12 mmol), 0.05M pH 7 buffer solution (1.06 equivalents), H2 O-THFr_ether (10 mL, 10 mL, 25 mL) was shaken on a Parr hydrogenator using 30% Pd-on - Celite (200 mg) for 16 hours at 50 psi H2 The catalyst was filtered and washed with small amounts of water. The aqueous layer was washed with ether (3 times), acidified portionwise with 1% cold aqueous HCl, extracted with ethyl acetate between each addition of HCl, and saturated with brine and thoroughly extracted with ethyl acetate. The ethyl acetate extracts were combined, washed with brine (5 times) and dried (MgSO 4). Solvent evaporation gave a solid residue which was triturated with methylene chloride (19.4 mg, 71%). IR (Nujol) * max: 3500 1785 16 1672 cm 1 ((C = O) UV UV (EtOH) Amax: 260 3450), 309 (e 6400). 1 Hmr (DMSO dg) 8: 5.54 (1H, d, J = 1.5, H-5), 3.88 (1H, m, H-1 '), 4.2 - 3.5 (2H, bs, 0-H), 3.65 (1H, dd, J = 6.5, J = 1.5, H-6), 2.28 (3H, s, CH 3) and 1.15 ppm (3H, d, J = 6, ch 3).

55

DK 161970 B

Method B

5 -1) (rR, 3S, 4R and 1'S, 3R, 4S) 4-acetylthio-3- (1,1-trimethylsilyloxy- - Γ -ethyl) -1 - (paran in trobenzyl -211 - tri phenyl phosphoranyl in the - 211 -acetate) -2-azetidinone (isomer B)

; H ATMS

S-r ^ Ag TMSCl AcCl TES csHsN </ ~ ^ ΡΦ3

CO PNB CO PNB

2 * 15 A suspension of (1'R, 3S, 4R and 1'S, 3R, 4S) spilled ν-3- (Γ-hydroxy-1'-ethyl) -1- (paranitrobenzyl-2 "-tri phenylphosphoranylidene-2 (acetate) - 2-azetidinone-4-thiolate (505 mg, 0.715 mmol) in THF (25 ml) was cooled to -15 ° C (ice-MeOH bath), treated dropwise with triethylamine (289 mg, 398 µl , 2.86 mmol), trimethylchlorosilane (310 mg, 362 µl, 20 285 mmol) and finally with imidazole (50 mg, 0.734 mmol), stirred for 3 hours at -15 ° C and at room temperature for 16 hours. (IR of an all in quota showed absence of hydroxyl group). The mixture was cooled to -15 ° C, diluted with CH 2 Cl 2 (20 mL), treated with pyridine (226 mg, 231 µL, 2.86 mmol) and acetyl chloride (168 mg, 152 µL, 2.14 25 mmol), stirred. for 0.5 hours, diluted with ether, washed with dilute aqueous HCl, water, 5% aqueous NaHCO 3, water and brine, and dried. The solvent was removed on the rotary evaporator and the residue was purified by filtration through a silica gel column (1:10 ratio, 3% to 10% ether in benzene) to give the title compound 30 (360 mg, 84.2%) mixed with a small amount of the desilylated derivative (30 mg, 7.8%). IR (liquid film) v v: 1750, 1790 (C = O), 1620

1 iflaX

(phosphorane) and 1518 cm -1 (NOg).

2) (1'R, 3S, 4R and rs, 3R, 4S) 4-acetylthio-3- (1'-hydroxy-r-ethyl) - ~ 35 -1- (paranotrobenzyl-2 "-tri phenylphosphoranylidene-2 (acetate) - -2-azetidinone (isomer B) 56

DK 161970 B

OTMS

J SAc i +) L SAc

AV_A H, (P AN-S

5 ΓΙ '—3-► I

J_μ ΡΦ, J-N ΑΦ, cA3 3

CO PNB CO PNB

2 2 10

A solution of (rR, 3S, 4R and 1RS, 3R, 4S) 4-acetylthio-3-r-trimethylsilyloxy-1'-ethyl) -1- (paranitrobenzyl-2 "-tri phenylphosphoranyliden-2" acetate) -2-azetidinone (360 mg, 0.504 nunol) was treated with TFA (3 drops) and stirred at room temperature for 18 hours. The mixture was diluted with ethyl acetate, washed with water, diluted aqueous NaHCO 3, water and brine, and dried (MgSO 4). Solvent evaporation gave title compound (334 mg, 100%). IR (CHCl3) i /: 1755, 1690 (C = O), 1620, 1605 (phosphorane) and 1520 cm -1

mAX

(NO2).

3) (rR, 5R, 6S and r $, 55.6R) paranitrobenzyl-2-methyl-6- (r- -hydroxy-1'-ethyl) -penem-3-carboxylate (isomer B) OH ° Η 25 A., _ (/ SAc λ Α, -τΑ J-'Caj oJ-i / 3

In CO PNB

CO PNB 2 2 1 2 3 4 5 6 /

A solution of (1'R, 3S, 4R and 1'S, 3R, 4S) 4-acetylthio-3- (1'-hydroxy-1'-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2 (3-Acetate) -2-azetidinone (410 mg, 0.638 mmol) in toluene (40 ml) was refluxed for a 7 hour period. Toluene was partially evaporated. The residue was passed through a silica gel (1 to 12 ratio) column (3%, 4% and 5% 6 ether in benzene) to give the title compound (151 mg, 65%) as a white solid, m.p. 161 to 161.5 ° C. IR (CDCl3) γmax: 3600, 3500-3400 (OH), 1780, 1608 (C = 0) and 1525 cm 1 1 (NO₂). Mr (CDClj) δ: 8.20 (2H, d, J = 7, Ho aromatic), 7.60 (2H, d aromatic

DK 161970 B

57), 5.57 (1H, d, J = 2, H-5), 5.29 (2H, center of ABq, J =

15, CH2-PNB), 4.2 (1H, dq, J = 7, J = 6, Η-Γ), 3.67 (1H, dd, J

= 7, J = 2, H-6), 2.33 (3H, s, CH 3) and 1.33 ppm (3H, d, J = 6, CH 3).

5 - Analysis for C16H16W;

Calculated: C: 52.74, H: 4.43, N: 7.69, S: 8.80,

Found: C: 52.67, H: 4.41, N: 7.71, S: 8.96.

4) (1'R, 5R, 6S and 17S, 55.6R) 6- (1'-hydroxy-Γ-ethyl) -2-methylpenepene-3-carboxylic acid (isomer B)

OH, ° H

. hXt- £ Q ~ ·

15 XCO PNB CO H

2 ^

A mixture of (1'R, 5R, 6S and rs, 5S, 6R) paranitrobenzyl 6- (Γ-hydroxy-Γ-ethyl) -2-methylpenem-3-carboxylate (89 mg, 0.244 mmol), 20 THF -H 2 O ether (15 ml, 10 ml, 30 ml), a 0.05M pH 7 buffer solution (5.06 ml, 0.253 mmol) and 30% Pd-on-Celi tea (250 mg) were shaken on a Parr hydrogenator for 3.5 hours at 45 psi H2-Workup, identical to the one described previously, gave the title compound (32 mg, 57%).

25

Example 14 (rs, 5R, 6R and rR.5S, 6S) 6- (Γ-hydroxy-Γ-ethyl) -2-methylpenem-3-carboxylic acid (isomer A)

DK 161970 B

58 1) (1'S, 3R, 4R and 1'R, 3S, 4S) 4-acetylthio-3- (r-roethoxymethoxy-1'-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" - acetate) -2-azetidinone (isomer A) 5 and 2 and 3 and 2 and 3 'λΥ * 9 Yysac

CO PNB CO PNB

2 2 10

Isomer A of 4-acetylthio-3- (r-methoxymethoxy-r-ethyl) -1- (para-nitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azetidinone was prepared as described elsewhere for isomer C of paranitrobenzyl di the oxycarbonyl derivative, yield 85%. IR (pure) in /: 1750 and 1690 cm -1 (C = O).

2) (rs, 3R, 4S and 1 / R, 3S., 4S) 4-Acetylthio-3- (1'-hydroxyurethyl, yl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2 - azetidinone (isomer A) 20 and 2 and 3 oh _ in JN ρφ. J-Μ. , ρφ θ 'r3 O 3

CO PNB CO PNB

2 2 25

Isomer A of 4-acetylthio-3- (r-methoxymethoxy-1'-ethyl) -1- (para-nitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azetidinone (500 * mg, 0.68 mmol ) was added to a cooled solution (0 ° C) of trifluoroacetic acid (50 ml) and water (10 ml) and stirred for 15 minutes in ice and 3 hours at room temperature. The reaction mixture was concentrated, dichloromethane was added and the solution was washed with sodium bicarbonate, water and brine, dried and concentrated to give the title compound (450 mg, 96%). IR (neat) 8: 3400 (OH), 1745 and 1690 · - i (ΠαΧ 1 cm cm’ (C = O).

59

DK 161970 B

3) (rs, 5R, 6R and 1'R, 5S, 6S) paranitrobenzyl 6- (r-hydrox, y-r-ethyl) -2-methyl-penem-3-carboxylate (isomer A) 5

OH

OH i 1 / SAc r ^ S \ λ-τ - 'rxy ~' ^ ° Λο, ηβ

10 io2PNB

Prepared as described for isomer C of the paranitrobenzyl dioxycarbonyl derivative, yield 45%. mr (CDCl3) 8: 7.93 (4H, ABq, aromatic), 5.68 (1H, d, J = 4.0, H-5), 5.33 (2H, ABq, benzyl), 4, 3 (1H, m, H-1 '), 3.8 (1H, dd, J = 4.0, H-6), 2.41 (3H, s, CH 3), 2.31 (1H, s, OH) and 1.42 ppm (3H, d, J = 6, CH 3). IR (CHCl3) v: 3100-3600 (OH), 1780 and 1710 cm -1 (C = O). max. 4) (1 ', 5R, 6R and rR, 5S, 6S) 6- (r-hydroxy-r-ethyl) -2-methyl-penem-3-carboxylic acid (isomer A)

OH

"-for- · - · 'tcQ ·" ·

o CO H

CO.PNB l 2 1 2 3 4 5 6

A mixture of isomer A of paranitrobenzyl 6- (1'-hydroxy-r-2-ethyl) -2-methyl-penem-3-carboxylate (82 mg, 0.2 mmoil), paladium Celite (30%, 400 mg), THF (10 ml), ether (25 ml), water (10 ml) 4 and buffer (0.05M, pH 7, Fisher No. SO-B-108) (4 ml of hydro 5 was generated on a Parr shaker at an initial hydrogen pressure of 45 psi * 6 for 4 hours. The catalyst was removed by filtration on Cel in tea and washed with water. The filtrates were washed with ether and the aqueous layer acidified in the cold hydrochloric acid (0.25M) and extracted with ethyl acetate (5 x 10 ml). The combined organic extracts were washed

DK 161970 B

60 with brine, dried and concentrated. The foamy solid was triturated in ether to give a white solid (20 mg, 44%).

IR (nujol) ymax: 3500 (OH), 1765 and 1665 cm -1 (C = 0). UV (EtOH)

Amax: 301 (6 5922), 260 (e 4280).

5 -

Example 15 (TR, 5R, 6 $ and 1'S, 5S, 6R) 2-Aminomethyl-6- (r-hydroxy-r-ethyl) - penem-3-carboxylic acid (isomer B) (rR, 3S, 4R and 1S, 3R, 45) 4-azidoacetylthio-3- (1 H -hydroxy-1 H -ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2lt acetate) 2-azetidinone (isomer B) 20

OH

TMSC1 ClCOCH2H3 β -► ---- * · -

--N ρφ TEA

C02Pl, B

OH

1 SCOCH N

. X

CO_PNB

Z 4

A cold (ice-MeOH bath) suspension of (1'R, 3S, 4R and 1'S, 3R, 4S) silver-3- (1'-hydroxy-1'-ethyl) -1- (paranitrobenzyl-2 "- triphenylphosphoranylidene-2 "acetate) -2-azetidinone-4-thiolate (970 mg, 1.37 mmol, from 1 g of the corresponding trityl) in THF (40 ml) was treated dropwise with trimethylchlorosilane (0.695 ml, 595 mg, 5.48 mmol), triethylamine

DK 161970 B

61 (0.765 ml, 555 mg, 5.49 mmol) and imidazole (50 mg, 0.734 mmol).

The mixture was stirred under N 2 for 17 hours, then cooled to -15 ° C (ice-MeOH bath) and azidoacetyl chloride (406 mg, 3.40 mmol) added.

It was stirred for 30 minutes (following reaction evolution at 5 tic). The solid was filtered and washed with ether. The filtrate was diluted with more ether, washed with 1% aqueous HCl, water, 1% aqueous NaHCO 3, water and brine, and dried (MgSO 4). The residue, which was obtained after solvent evaporation, was taken up in moist CH 2 Cl 2 (50 ml) and treated with TFA (3 drops, followed by decomposition 10 of THS ether by tic). The methylene chloride solution was then washed with 1% aqueous NaHCO 3, water and brine and dried (MgSO 4). The residue was passed through a si 1 in cage! (8 times its weight) column (benzene ether 1: 1, ether and ethyl acetate ether 1: 1) to give title compound (565 mg, 69.8%). IR (film) v: 3500-

fliaX

15 -3200 (0-H), 2100 (N3), 1755, 1609 (C = 0), 1620-1605 (phosphorane) and 1518 cm-1 (NO2).

(rR, 5R, 6S and 1'S, 5S, 6R) paranitrobenzyl-2-azidomethyl-6- (r- -hydroxy-Γ-ethyl) -penem-3-carboxylate (isomer B)

OH

OH I

I SCOCH _N __

ArY - J_ Pi Δ

o ^ 3 'CO PNB

25 ΗΡΝΒ

A solution of (rR, 3S, 4R and 1'S, 3R, 4S) 4-azidoacetylthio-3- (1'-hydroxy-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranyli-2-acetate) - 2-azetidinone (500 mg, 0.731 mmol) in toluene (100 ml) was allowed to reflux under N 2 for 30 minutes. The solution was concentrated in vacuo and the residue passed through a silica gel (5 g) column (3.5-4% ether-benzene) to yield the title compound (193 mg, 65.1%) as a yellow solid, m CDCl ^) δ: 8.13 (2H, d, Ho aromatic), 7.52 (2H, d, Hm aromatic), 5.59 (1H, d, J = 1.8, H-5), - 5.27 (2H, center of ABq, J = 13.5, CH2-PNB), 4.50 (2H, center of ABq, J = 16, CH2-N3), 4.15 (1H, m, Η -Γ), 3.73 (1H, dd, J = 6.3, J = 1.8, H-6), 1.92 (1H, d, J = 4, 0-H), and 1.33 ppm (3H, d, J = 6.3, CH 3). IR (CHCl3) νmx: 2110 (N3), 1785, 1705 (C = 0)

DK 161970 B

62 and 1520 cm -1 (NO 2).

(1 / R, 5R-, 65 and 1'S, 5S, 6R) 2-Aminomethyl-6- (1H-hydroxy-r-ethyl) -penem-3-carboxylic acid (isomer B)

OH

X s x_ '' i-r H? v 1 Γ I Jr τ », - * - * L_n // 2 10 0 V»

A solution of (1'R, 5R, 6S and 1'S, 5 $, 6R) paranitrobenzyl-2-azidomethyl-6- (1'-hydroxy-1'-ethyl) -penem-3-carboxyl at (25 mg, 0.062 mmol) in THF-ether water (6 mL, 6 mL, 15 mL) was shaken in a Parr 15 hydrogenator for 2.5 hours at 40 psi H2 using 10% Pd-on-charcoal (100 mg). The catalyst was filtered and washed with small amounts of water. The aqueous layer was washed with ether (3 times) and lyophilized to give the title compound (11 mg, 73%). x Hmr (D 2 O) S: 5.75 (1H, d, J = 2, H-5), 4.30 (1H, center of m, J 1, 6.5, H-1 '), 4.02 ( 1H, dd, J = 6.5, J = 2, H-6) and 1.37 ppm (3H, d, J = 6.5, CH 3). IR (nujol mull) vmxi 3550-2450 (O-H, NH), 1765 (OO) and 1600 cm cm "(CO₂“). UV (H2), λλ: 309 (e 3650), 255 (e 2815) .

Example 16 (1'RiSR 2 S and ,55,5S, 6R) -2- (4-Aminobutyl) -6- (1'-hydroxyethyl) penem-3-carboxylic acid (isomer B)

XCOOH

35

DK 161970 B

63 (rR, 3S, 5R and rS, 3R, 4S) 4- (6-azidobutanoylthio) -3- (Γ-hydroxyethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate ) -2-azetidinone 5H + · S -., - ^ THSC1 N ^ CH ^^ COCl H, i 'TEA, Im .- *' CH N H2 ° Λ-N oo cr ^ v> PPhn 10 I 3

COOPNB

_ ^ Xr - C (CH2) 4N3

jX

0 - r-PPh3

COOPNB

A solution of (1'R, 3S, 4R and 1'S, 3R, 4S) silver 3- (1'-hydroxyethyl) -1- (paranitrobenzyl-2 "tri-phenylphosphoranylidene-2" acetate) -2 - azetidinone-4-thiolate (3.03 g, 4.28 mmol) in dry THF (55 mL), kept under nitrogen atmosphere, cooled to -25 ° C and successively treated with triethylamine (2.39 mL, 17.12 mmol), trimethylchlorosilane 2-5 (2.18 ml, 17.12 mmol) and imidazole (0.10 g, 1.47 mmol). The reaction mixture was stirred at -25 ° C for 0.25 hours, the cooling bath removed and stirring continued for 16 hours. The reaction mixture was cooled to 0 ° C and diluted with CF 3 C (55 mL); it was then successively treated with pyridine (0.73 mL, 9.0 mmol) and with a solution of 4-aminobutanoyl chloride (1.36 g, 8.56 mmol) in CH 2 Cl 2 (10 mL). The reaction mixture was stirred at 0 ° C for 1 hour and filtered through a Celite pad. The pad was washed with Cf C (25ml); the filtrate and washings were combined and diluted with EtOAc (300 mL). The organic solution was washed with 1N HCl solution, H 2 O, saturated NaHCO 3. , And dried over anhydrous MgSO4 and concentrated on a rotary evaporator to an orange syrup (3.83 g). The syrup was dissolved in C ^C C (75 mL) and water (4 mL), and TFA (0.2 mL) was added; the reaction mixture was stirred at 23 ° C for 1.5 hours, washed with 64

DK 161970 B

NaHCO 3 and H2 O, dried over anhydrous Na 2 SO 4 and concentrated to an orange syrup (3.4 g). Purification of the syrup was achieved by column chromatography (silica gel G 60, 80 g; eluent: EtOAc in CH 2 Cl 2 10% 75%). Evaporation of the appropriate fractions gave an oil; 2.14 g, 67.7%.

Analysis for γ y g gNgOySP:

Calculated: C: 61.23, H: 5.00, N: 9.65, S: 4.42,

Found: C: 61.17, H: 5.10, N: 10.02, S: 3.71.

10 (1'R, 5R, 6S and r $, 5S, 6R) paranitrobenzyl-2- (5-azidobutyl) -6- - (Γ-hydroxyethyl) -penem-3-carboxylate OH 9 f -, - ^ κνΛ λ Α — Γλ 15 QJ — N Toluene 2 4 3 C = PPh3 C00PN3

COOPNB

A solution of (rR, 3S, 4R and rs, 3R, 4S) 4- (6-azidobutanoyl-20-thio) -3- (1'-hydroxy-1'-ethyl) -1- (paranitrobenzyl-2 "- triphenylphosphoranyliden-2 "acetate) -2-azetidinone (2.04 g, 2.81 mmol) in a toluene - CH 2 Cl 2 mixture (30: 1, 310 ml) to reflux for 9 hours under a nitrogen atmosphere (CH 2 Cl 2). removed at the beginning of reflux). The reaction mixture was cooled to 23 ° C and the toluene was removed in vacuo to leave an orange residue which was purified by column chromatography (silica gel 60, 45 g; eluent, ether in petroleum ether, 1: 1 - * 9: 1). The appropriate fractions were combined and concentrated to a syrup which crystallized from an ether-petro-ether mixture, 0.443 g, m.p. 85 ° C, 35.2%.

Analysis for Cjg ^ jNNO₂S:

Calculated: C: 51.00, H: 4.73, N: 15.65, S: <7.17,

Found: C: 51.05, H: 4.85, N: 15.86, S: 7.19.

The fractions corresponding to unreacted starting material were cyclized as described above to give an additional amount of 35 (0.276 mg, 21.9%) of the title compound, v: 2100 (NQ), 1770 (C = O, β-lactam) and 1705 cm -1 (C = O, PNB ester) UV (H2 O 23 ° C) λ: 268 (c 13757), 316 (c 9826). iHmr (CDCl3) 8: 1.36 (d, JH 2 = 6.3 Hz, 3H, methyl), 1.52 - 1.77 (m, 4H, H-2 ', H-3'), 2.57 - 3.00 /

DK 161970 B

65 (m, 2H, H-4 '), 3.00 - 3.42 (m, 2H, Η-Γ), 3.72 (dd, JH_6_H_5 = 1.6 Hz, = 6.4 Hz, H- 6), 4.02 - 4.42 (m, 1H, Η-Γ), 5.32 (ABq, = 13.6 Hz, 2H, CH 2 of PNB ester), 5.60 (d, J g = 1.6 Hz, 1H, H-5), 7.61 (d, JH H (J = 8.8 Hz, 2H, Hm of PNB ester) and 8.21 ppm (d, JHoHm = 8.8 Hz, 2H, Ho of PNB ester).

(rR, 5R, 6S and 1S, 5S, 6R) 2- (4-Aminobutyl) -6- (1'-hydroxyethyl) penem-3-carboxylic acid

10H

OH

(pT Vcch) H 10% -d / C-v oj_N 2 4 3 DME: Et 2 O, H 2 O 0 + -

COOPNB

15

To a solution of (rR, 5R, 6S and 1'S, 5S, 6R) paranitrobenzyl 2- (6-azidobutyl) -6- (r-hydroxyethyl) -penem-3-carboxylate (0.54 g, 1.21) mmol) in dimethoxyethane (50 ml) was added ether (50 ml), water (50 ml) and 10% palladium-on-charcoal (0.54 g). The reaction mixture was hydrogenated under 45 psi of hydrogen at 23 ° C for 3 hours. The reaction mixture was filtered over a Cel in tea pad and the filtrate diluted with ether. The aqueous phase was separated, washed with ether and lyophilized. The crude title compound was purified by hplc. IR (KBr) γ:

j fflaX

1760 (C = O / Mactam) and 1565 cm -1 (C-O, carboxylate). Mr (D2 O) S: 1.32 (d, JCH3_H_r = 6.4 Hz, 3H, CH3), 1, 45 - 1.85 (m, 4H, H-1 ', H-3'), 2.50 - 3.20 (m, 4H, Η-Γ, H-4 '), 3.84 (dd, ϋμ_6_Η_Γ = 6.1 Hz, JH.6.H "5 = 1.4 Hz, 1-H, H-6), 4.00 - 4.45 (m, 1H, H1") and 5.62 ppm (d , JH_5_H_6 = M Hz, IH, H-5). UV (H2 O): 260 (c 4240), 302 (c 5480).

30 4 66

DK 161970 B

Example 17 (1 "R, 5R, 6S and 1/5, 5St6R) -2- (trans-3 H -amino-1 H -cyclobutyl) -6- (1" - hydroxy-γ'-ethyl) -penem-3-carboxylic acid (isomer B)

5 OH

0Χ> 0 ···· " '2

rooh

10 (1 "R, 3S, 4R and 1" S, 3R, 4S) 4- (trans-3, -azidocyclobutanoylthio) - 3- (Γ1-hydroxy-1 "-ethyl) -1- (paran trobenzyl-2) "-Tri-phenylphosphoranylidene-2" - acetate-2-azetidone non 15 OH

A ._ / Case CIC ^ V-N

In TMSC1 _v 3

J N TEA t Im c H

cr \ C = PPh 5 5 I 3

COOPNB

20 ° H o H + L-

r LI

C = PPh 25 I 3

COOPNB

A solution of (1'R, 3S, 4R and r $, 3R, 4S) of silver ν-3- (Γ-hydroxy-30-ethyl) -1- (paranitrobenzyl-2 "-tri phenylphosphoranylidene-2" acetate) 2 - azetidinone-4-thiolate (1.01 g, 1.43 mmol) in dry TUF (25 ml), kept under nitrogen atmosphere, cooled to -40 ° C and treated successively with triethylamine (0.80 ml, 5, 74 mmol), trimethylchlorosilane (0.726 ml, 5.72 mmol) and imidazole (0.10 g, 1.47 mmol). The reaction mixture was heated to -15 ° C, stirred for 3 hours, the cooling bath removed and stirring continued for 18 hours. The reaction mixture was cooled to -15 ° C and diluted with CH 2 Clg (25 mL); it was then treated with pyridine (0.15 ml, 1.85 mmol) and trans-3-azidocycloidine.

DK 161970 B

67 butanoyl chloride (0.274 g, 1.72 mmol). The cooling bath was removed and the solution was stirred for 1 hour and treated with pyridine (0.15 mL, 1.85 mmol) and trans-3-azidocyclobutanoyl chloride (0.274 g, 1.72 mmol). The reaction mixture was stirred at 23 ° C for 1 hour and filtered through a Celite pad. The filtrate was diluted with EtOAc (100 mL) and washed with 1N HCl, H 2 O, saturated NaHCO 3 solution and H 2 O, dried over anhydrous MgSO 4 and concentrated on a rotary evaporator to an orange syrup (1.47 g). To a solution of the syrup in CH 2 Cl 2 (50 mL) was added H 2 O (2 mL) and TFA (0.2 mL). The reaction mixture was stirred at 23 ° C for 2 hours, washed with saturated NaHCO 3 solution and H 2 O, dried over anhydrous Na 2 SO 4 and concentrated to an orange syrup (1.1 g). Purification of the syrup was achieved by column chromatography (silica gel 60, 20 g; eluent EtOAc ether 35% - * 70%). Evaporation of the appropriate fractions gave the title compound as an oil; 0.77 g, 74.4%. IR (pure) v ·. 3440 (OH), 2100 (N,), 1755 (C = O, δ-lactam), liiaX 1 + 3 1735 (C-0), 1680 (C-0) and 1525 cm -1 (aromatic).

(1 "R, 5R, 6S and 1" S, 5S, 6R) paranitrobenzyl-2- (trans-3β-azido-cyclobutyl) -6- (111-hydroxy-1 "-ethyl) -penem-3- carboxyl at 20 '' Η Ϊ / \ f C = PPh 0 \ 25 coopnI coopkb

A solution of (1 "R, 3S, 4R and 1" S, 3R, 4S) 4- (trans-3'-azido-cyclobutanoylthio) -3- (1 "-hydroxy-1" -ethyl) -1- ( paranitrobenzyl-2 "- tri-phenylphosphoranylidene-2" -acetate) -2-azetidinone (2.27 g, 3.14 30 mmol) in CHCl 3 (40 ml) was diluted with toluene (300 ml) and refluxed under a nitrogen atmosphere for 6 hours. The first 60 ml of the solution (CHCl3 + toluene) was removed with a Dean-Stark trap. The reaction mixture was cooled to 23 ° C and the solvent evaporated under reduced pressure leaving an orange syrup which was purified by a silica gel column (silica gel 60, 35 g, eluent, ether-benzene, 0 - + 6%). Evaporation of the appropriate fractions gave the title compound, 0.38 mg, m.p. 134-5 ° C, 27.3%.

Analysis for CjgHjgNgOgS: 68

DK 161970 B

Calculated: C: 51.24, H: 4.30, N: 15.73, S: 7.20,

Found: C: 50.98, H: 4.20, N: 15.83, S: 7.10.

IR (KBr) v: 2110 (No), 1765 (C = O, ε-lactam), 1690 (C = 0 PNB ester), 1510 (NO0) and 1355 cm ~ l (NO₂). 1 Hmr (CDCl 3) S: 1.36 (d, 5 JCH 3_H - 6.3 Hz, 3H, CH 3), 2.0 - 2.75 (m, 4H, H-2 ', H-4'), 3, 67 (dd, JH_6.H_5 = 1.5 Hz, JH.6.H.1B = 6.5 Hz, 1H, H-6), 3.8 - 4.55 (m, 3H, H-Γ, H -3 'and H1 "), 5.30 (ABq, Ja_b = 13.6 Hz, 2H, CH2-Ph-NO2), 5.60 (d, JH_5_H.6 - 1.5 Hz, 1H, H-5 ), 7.59 (d, JHo-Hm = 8.8 Hz '2H' H "m of PNB) ° 9 8'20 (d> JHm-Ho 8'8 Hz> 10 2H, H-0 of PNB) . UV (CHCl3, 23 ° C) 266 (e 13050) and 322 o max ppm (c 10008). The unreacted phosphorane was recycled mixed with Ph3P-0 and cyclized as described previously to give an additional amount of the title compound: 0.145 g, 10.4% in a total yield of 37.7%.

15 (1 "R, 5R, 65 and riS, 5S, 6R) -2- (trans-3β-amino-r-cyclobutyl) -6- (1" -hydroxyethyl) -penem-3-carboxylic acid 20. ... -r ^ s \ / \ 10% Pd / c —Γ ^ \ y \

TZOOPNB COOH

To a solution of (1 "R, 5R, 6S and 1" S, 5S, 6R) paranitrobenzyl - 2- (trans-3'-azidocyclobutyl) -6- (r'-hydroxyethyl) -penem-3-carboxylate (0.33 g, 0.74 mmol) in dimethoxyethane (40 ml) was added ether (40 ml) and 10% palladium-on-charcoal (0.33 g). The reaction mixture was hydrogenated under 45 psi H2 for 3 hours and filtered over a Celite pad.

The pad was washed with water and the filtrate and washings were combined and diluted with ether. The aqueous phase was separated, washed with ether and lyophilized, 0.20 g, 95%. UV (H2 O, 23 ° C) λ: 258 (e 2725) and 306 (e 3613). The crude material was triturated with water and the white solid filtered and dried over P P under high vacuum for 5 hours, 84 mg, 40%. x Hmr (D 2 O) S: 1.34 (d, η η-2 "-Η-1" = 6.3 Hz, 3H, H-2 "), 2.3 - 2.7 (m, 4H, H 2 ', H-4'), 3.90 (dd, JH-6-H-5 = 1.5 Hz 'JH-6-H1' = 6.1 Hz '1H' H "6 ^, and 5.68 ^ d 'JH-5-H-6 = 1) 5 Hz' 1H 'H_5) - UV (H2 ° 23 ° C) W 258 4738) /

DK 161970 B

69 and 306 (e. 6318). The filtrate was purified at hplc, 58 mg. UV (F₂O, 23 ° C): 257 358 ° 09 306 5033)

Example 18 5 (1'S, 5R, 6S and 1R, 5S, 6R) β-trimethylsilylethyl 6- (r-acetoxy-r-ethyl) -2-methylpenem-3-carboxylate (Isomer C) OA c Ή> -

co2 ^ - ^ N

3- (1'-Hydroxy-Γ-ethyl) -1- (β-trimethylsilylethyl -2 "- triphenyl - phosphoranylidene-2" acetate) -4-trityl thio-2-azetidinone STr J. STr I 1) LDA_ Me | on ✓—, N ^ pph, 2) CHCHO * \ —N pph3! 1 ^ γ Ύ / ^ siMe3 C ° 2 2

To a solution of diisopropylamine (185 mg, 1.84 mmol) in tetrahydrofuran (5 ml) at -78 ° C was added n-butyllithium (1.3 ml, 2.0 mmol) with stirring. After 5 minutes, a solution of 1- (β-trimethylsilylethyl-2'-tri phenylphosphoranylidene-2'-acetate) -4-trityl thio-2-azetidinone (1.27 g, 1.67 mmol) was added. tetrahydrofuran (15 ml) dropwise over 20 minutes with stirring. After 2 minutes, freshly distilled acetaldehyde (1 ml) was added and the solution was stirred for 5 minutes.

Hydrochloric acid (12.6 ml, 0.3M) was added and the mixture * temperature was allowed to rise to 23 ° C. Water and ethyl acetate (20 ml each) were added, which was shaken and separated. The organic phase was washed with water and saturated sodium chloride (20 ml each), dried and the solvent was evaporated in vacuo to give the crude product, 1.37 g. The product was absorbed from methylene chloride on 7 g of silica gel and placed (dry) on a 28 g silica gel column. The column was eluted with ether (100 ml) and then with ether / ethyl acetate 1: 1 (50 ml). The first 20 ml of column

DK 161970 B

The 70 fractions were discarded. The residue was combined and the solvent was evaporated in vacuo to give a product, 1.03 g. This product was absorbed from ether on a 50 g silica gel column (wet). The column was eluted with ether (680 ml) and then with ethyl acetate (200 ml).

Later fractions were combined (substantially low Rf stain on tic) and the solvent was evaporated in vacuo to give partially purified title compound, 440 mg (33%). IR v: 3400 (OH) and 1750 cm "1 (1 / Mactam and ester). 1 Hmr (CHClg) δ: too poorly distributed to assess peaks other than aromatics and trimethylsilyl.

Silver 3- (1'-hydroxy-17-ethyl) -1- (β-trimethylsilylethyl-2 "-triphenylphosphoranylidene-2,1-acetate) -2-azetidinone-4-thiolate

OH OH

STr AgNO / pyridine - [25 A solution of silver nitrate (425 mg, 2.5 mmol), pyridine (79 mg, 1.0 mmol) and water (10 ml) was added to a solution of the above compound (403 mg, 0.50 mmol) in ether (10 ml). The mixture was stirred vigorously for 1 hour. The precipitate was collected by filtration and washed with water and ether to give the title mercaptide, 267 mg 30 (80%). IR in / max: 3400 (OH) and 1750 cm -1 (Mactarn and ester).

DK 161970 B

71 4-Acetylthio-3- (r-acetoxy-r-ethyl) -1- (O-trimethylsyl) ethyl ^ -2ll - triphenylphosphoranylidene-2 "acetate) -2-azetidinone OAc OH I SAc

AcCl / pyridine He / S-S 'Mo --- "V" _J PPh.

/ -Vmi. A solution of acetyl chloride (70 mg, 0.88 mmol) in methylene chloride (1 ml) was added dropwise to a solution of the above-mentioned silver mercaptide (267 mg, 0.40 mmol) and pyridine (70 mg, 0.88 mmol) in methylene chloride (5 ml) at 0 ° C. The mixture was stirred at 0 ° C for 1.5 hours and then at 23 ° C for 15 minutes. The precipitate was filtered off and the solution washed with 0.1M hydrochloric acid and 0.1M sodium bicarbonate (10 ml each). The solvent was evaporated in vacuo to give title compound, 153 mg (59%). IR v: 3450 (OH, 1750 (0-1ac- in max tam and ester) and 1690 cm -1 (thioester). Mr (CDCl 3) δ: 7.5 - 8.2 (m, 15H, Ph), 5.85 (br, 1H, H-4), 3.0 - 5.0 (unallocated, 4H, OCH, 20CH2, H-3), 2.0 - 2.6 (3 singlets, 6H, OAc, SAc), 0.9-1.7 (m, 5H, CH 2, C 2 Si) and 0.20 ppm (s, 9H, SiMe 2).

(rS, 5R, 6S and TR, 5S, 6R) O-trimethylsilylethyl 6- (r-acetoxy-1'-ethyl) -2-methylpenem-3-carboxylate (isomer C)

TC ca I Η H

0J ~ "\ f ^ PPh3 Δ tO J 2 30 2 -4.

A solution of the aforementioned phosphorane (15 mg, 0.23 mmol) in toluene (15 ml) was heated at reflux for 2 hours.

The solution was mixed with 1 g of silica gel and the solvent evaporated in vacuo. The silica was placed on a 4 g silica gel column (dry) and eluted with ether. The first 5 ml fraction (simple high Rf stain on tic), after evaporation of the solvent, afforded the title compound, 65 mg (76%) as a waxy solid. IR v: 1790 (β-lactam), 1740 max

DK 161970 B

72 (ester) and 1700 cm "1 (OAc). X Hmr (CDClj) δ: (d, J = 2 Hz, 1H, H-5), 5.4 (m, 1H, Η-Γ), 4.3 (m, 2H, OCH 2), 3.90 (q, J = 2 Hz, 4 Hz, 1H, H-7), 2.37 (s, 3H, 2-CH 3), 2.11 (s, 3H, OAc ), 1.42 (d, O = 6.5, Hz, 3H, 2'-CH3), 1.1 (m, 2H, CH2 Si) and 0.05 ppm (s, 9H, 5 SiMe3). to be a single isomer.

Example 20 (1'R, 5R, 6S and rs, 5S, 6R) 6-1 '-amino-Γ-ethyl) -2-methylpenem-3-carboxylic acid 10 102 ^ 15

Process A

(rR, 3S, 4R and 1'S, 3R, 4S) S-q'-azido-1'-ethylD-1-tparanitro-benzyl-2ll-triphenylphosphoranylidene-2 "acetate) -4-tritylthio-20-2-azetidinone (isomer B)

PMs N

25 σ Ν \ ^ Ρφ3

CO PNB I

2 CO ^ NB

A solution of (1'S, 3S, 4R and 1R, 3R, 4S) 3- (1-methanesulfonyl-oxy-Γ-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" -acetate) - 4-Tritylthio-2-azetidinone (isomer C) (12.36 g, 13.4 mmol) in 10% H 2 O-HMPA (135 ml) was heated at 85 ° C for 7 hours in the presence of sodium azide (1.75 g, 27.0 mmol). The solution was then poured into 35 cold water (1 liter) and the reaction product which crystallized was collected by filtration. Redissolving in dichloromethane, washing with brine and drying (MgSO4) gave the azidophosphorane as a yellow foam after evaporation of the solvent, 11.5 g (98.9%). It 73

DK 161970 B

! was used as such in the next step. IR ν (CHCl1): 2100 (N,), 1740 and 1610 cm "1 (C = O).

(TR, 3S, 4R and 1'S, 3R, 4S) 4-Acetylthio-3- (1-azido-1H-ethyl) -1-5 - (paranitrobenzyl-2 ”-triphenylphosphoranylidene-2" acetate) -2 - -acetidinone (isomer B)

N N

X __ ^ - Sc * 3 ^ L / S> 2 "9 SCOCH, 10 ο ^ ΝγίΙ, φ3 'co2pnb co2pnb co2pnb

A cooled solution (5 ° C) of (rR, 3S, 4R and 1'S, 3R, 4S) 3- (Γ-15-azido-Γ-ethyl) -1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2u-acetate ) -4-Tritylthio-2-azetidinone (8.9 g, 10.25 mmol) in dichloromethane (30 ml) was treated with a solution of mercury acetate (2.12 g, 6.66 mmol) in methanol (30 ml). After stirring at 5 ° C for 0.5 hours and at room temperature for 1.5 hours, the solvent was evaporated and the crude mercuric salt was redissolved in dichloromethane and washed with dilute NaHCO 3 and brine. After drying (MgSO C and treated immediately with pyridine (1.66 g, 21 mmol) and dropwise with acetyl chloride (1.65 g, 21 mmol). The reaction mixture was stirred at 5 ° C for 1 hour. The precipitated mercuric chloride was filtered off and the filtrate was washed successively with dilute HCl, NaHCO 3 and brine, then the organic solution was saturated with hydrogen sulfide at 5 ° C to precipitate the remaining mercury impurities as mercuric sulfide. one after evaporation of the solvent was purified on a silica gel column (8.5 x 9 cm), eluting with dichloromethane (500 ml) and 15% acetonitrile dichloromethane, 5.1 g, (74.6%). Hinr (CDCl 3) S: 3.70 (1H, * n, Η-Γ), 2.98 (1H, m, H-3), 2.33 and 2.20 (3H, 2s, acetyl), 1.28 (3H, d, J = 6.2 Ha, H-2 '). IR / (CHCK): 2115 (fU, 1758, 1693 and 1620 cm''1ΧΧΧ 3 <3 (C-O)).

35 74

DK 161970 B

(1'R, 5R, 6S and 1'S, 5S, 6R) paranitrobenzyl 6- (1'-azido-Γ-ethyl) -2-methylpenem-3-carboxylate (isomer B) N 13

5 X __ ^ coch3 -V-rs \ rH

J = G. - · 2¾

C02PNB

A solution of (1'R, 5R, 6S and 1'S, 5S, 6R) 4-acetylthio-2- (1 '- azido-1'-ethyl) -1-paranitrobenzyl-2 "-triphenylphosphoranylidene-2" - (acetate) -2-azetidinone (5.1 g, 13.1 mmol) in toluene (100 ml) is refluxed for 2 hours under nitrogen. The solvent was evaporated and the reaction mixture purified by chromatography on a silica gel column (7 15 x 5 cm). Azidopenemen were eluted with dichloromethane (additional elution was allowed with 10% ether-dichloromethane to recover 1.82 g of unreacted phosphorane): 1.21 g (40.6%), m.p. 132-34 ° C. x Hmr (CDClg) δ: 8.21 (2H, d, Hm aromatic), 7.60 (2H, d, Ho aromatic), 5.51 (1H, d, 0 = 1.6 Hz, H-5), 5.33 (2H, ABq, H-benzyl), 3.92 (1H, dq, J = 8, 6.4 Hz, Η-Γ), 3.67 (1H, dd, J = 1.6, 8 Hz, H-6), 2.37 (3H, s, CH 3), 1.46 (3H, d, J = 6.4 Hz, H-2 '). IR (CDCl3): 2123 (N3), 1788 and 1712 cm -1 (OO).

(1'R, 5R, 6S and rs, 5S, 6R) 6- (r-amino-r-ethyl) -2-methylpenem-.

-3-carboxylic acid (isomer B)

N NH

- -ο-

CC 2 PNB * 2 ° 2H

A solution of (1'R, 5R, 6S and rs, 5S, 6R) paranitrobenzyl 6- (1 '- azido-r-ethyl) -2-methylpenem-3-carboxylate (440 mg, 1.13 mmol) in 35 THF-ether water (1: 1: 1) (120 ml) was hydrogenated at 50 psi for 1 hour in the presence of 10% Pd-C (440 mg). The catalyst was filtered off, the filtrate extracted with ether and the aqueous phase lyophilized.

The crude amino acid (100 mg) was purified at hplc: 19.5 mg. ^ mr ^ 0) t 75

DK 16197 0 B

S: 5.69 (1H, d, J = 0.9 Hz, H-5), 3.94 (2H, m, H-6, H-1 '), 2.28 (3H, s, CH 3 ph) , 1.50 (3H, d, J = 6.4 Ha, H-2 '). IR νmx (Nujol): 1767, 1576 cm "1 (C = 0). UV (H₂O) λ ^: 300 m / i (e 5326).

Method B

(1'R, 3S, 4S and rs, 3R, 4S) 3- (r-Azido-r-ethyl) -4-tritylthio-2-azetidinone (Isomer B) »'fbT' -.

313) 2 t-Bu 15 A solution of (r $, 3S, 4R and rR, 3R, 4S) 1- (t-butyl di methyl si - • Tyl) -3- (r-methanesulfonyloxy-r-ethyl) - 4-Tritylthio-2-azetidinone (Isomer C) (1.75 g, 3 mmol) and sodium azide (0.39 g, 6 mmol) in 10% H2 O: HMPA (15 mL) was heated under N 2 at 75-80 ° C in 3 hours. The reaction mixture was then diluted with ethyl acetate and washed several times with brine. The organic phase was dried (MgSO4) and evaporated leaving an oil which crystallized spontaneously. Trituration in ether and filtration gave 951 mg (76.5%) of the azido compound as a white solid, m.p. 185-90 ° C, decomp. mr (CDCl 3) S: 7.23 - 7.78 (15H, m, aromatic), 4.43 (1H, d, J = 3, H-4), 4.37 (1H, s, NH) 3.89 (1H, dq, J = 7, 6.5, Η-Γ), 3.16 (1H, dd, J = 7, 3, H-3), 1.50 (3H, d , J = 6.5, H-2 '). IR in / (CHCL ·): 3410 (n-H), 2123 L of ITlaX v (N3) and 1765 cm -1 (C = O).

(1'R, 3S, 4R and r $, 3R, 4S) 3- (r-Amino-1'-ethyl) -4-tritylthio-2-30-azetidinone (Isomer B) N X 2 * '_, ΧΥ ...

35 J-

DK 161970 B

76

A suspension of (rR, 3S, 4R and rs, 3R, 4S) 3- (1'-azido-1'-ethyl) -4-tritylthio-2-azetidinone (Isomer B) (1.0 g, 2 41 mmol) of platinum oxide (100 mg) in ethyl acetate (100 ml) was hydrogenated for 1 hour at a pressure of 50 psi. When the reaction was incomplete, 200 mg of platinum oxide was added and the mixture was hydrogenated for an additional 1 hour. Finally 200 mg of platinum oxide was again added and the reaction was continued for 2.5 hours.

Total amount of catalyst: 500 mg. Total time: 4.5 hours. The catalyst was then filtered off and the solvent was evaporated. The crude amine crystallized from ether: 700 mg (80%). Snip. 128-30 ° C. 1 Hmr 10 (CDCl 3) 8: 7.13 - 7.63 (15H, m, aromatic), 4.40 (1H, d, J = 2.5, H-4), 4.30 (1H, broad, H1 ), 3.30 (1H, dq, J = 5.1, 6.3, H-1 '), 3.03 (1H, dd, J = 5.1, 2.5, H-3), 1 , 20 (3H, d, J = 6.3, H-2 ') and 1.0 - 1.80 ppm (2H, broad, NH 2).

(1'R, 3S, 4R and 1S, 3R, 4S) 3- (rp-nitrobenzyloxycarbonylamino-Γ-ethyl) -4-tritylthio-2-azetidinone (Isomer B) JCL.sc * C02 «æ» u _, -V ".

H

A solution of (rR, 3S, 4R and 1'S, 3R, 4S) 3- (r-amino-1'-ethyl) -25 -4-tritylthio-2-azetidinone (Isomer B) (1.00 g, 2 57 mmol) in dichloromethane (100 ml) was cooled to 5 ° C and treated with p-nitrobenzyl chloroformate (0.61 g, 2.83 mmol) and pyridine (0.22 g, 2.83 mmol).

After stirring at 5 ° C for 45 minutes and at room temperature for 2.25 hours, the reaction mixture was washed with dilute HCl, brine, dried (MgSO 4) and finally evaporated to dryness. The crude carbonate was crystallized from ether: 1.03 g (70.5%). 147-50 ° C.

1 Hmr (CDCl 3) 8: 7.10 - 8.33 (19H, m, aromatic), 5.23 (2H, s, benzyl), 5.08 (1H, NH), 4.40 (1H, s, NH ), 4.29 (1H, d, J = 2.2, H-4), 4.10 (1H, dq, J = 8, 6, H-1 '), 3.18 (1H, dd, J = 2.2, 8, 35 H-3) and 1.23 ppm (3H, d, J = 6, H-2 '). IR (CHCL ·): 3395

in maX O

(N-H), 1765 and 1724 cm -1 (C = O).

77

DK 161970 B

(rR, 5R, 6S and rs, 5S, 6R) p-nitrobenzyl-2-methyl-6- (1'-p-nitro-benzylox, ycarbonylamino-r-ethyl) -penem-3-carboxylate (Isomer B )

NHCO-PNB NHCO ^ PNB

5 Λ. s *** '\ -r \ u - * CO PNB 2 10 The title product was prepared from (l'R, 5R, 6S and l'S, 5S, 6R) 3 - (1'-p-ni trobenzyloxycarbonylamide no-1' -ethyl) -4-triethylthio-2-azetidine non (isomer B) by the standard procedure; mp. 108-110 ° C. mr (CDCl 3) S: 7.50 - 8.40 (8H, m, aromatic), 5.58 (1H, d, J = 1.20, H-5), 5.35 (2H, ABq, benzyl ester) ), 5.20 (2H, s, benzylcarbamate), 4.90 (1H, wide NH), 4.20 (1H, dq, J = 6, 8, Η-Γ), 3.80 (1H, dd , J = 1.2, 8.0, H-6), 2.40 (3H, s, CH 3), 1.40 (3H, d, J = 6, CH 3).

IR max max * 3435 1777 and 1717 cm 1 ((c = 0) · p-nitrobenzyl ester can be subjected to catalytic hydrogenation as in the process of Example 43 (Method A) to form the corresponding carboxylic acid.

Example 21 Spilled v-1- (β-trimethylsilyl ethyl-V - tri phenyl phosphoranylidene-2 '-30 acetate) -2-azetidinone-4-thiolate 4β / SAg <Α-νρφ3 / c ”

DK 161970 B

di-g-trimethyl Si Ίylethyl fumarate 5 Π * "(CH) Si T

o pyridine J 6 O

To a cold (-10 ° C) ether (20 ml) solution of 2-trimethylsilyi-ethanol (4.73 g, 0.04 mmol) [H. Gerlach Helv. Chim. Acta 60, 3039 (1977)] and pyridine (5.66 ml, 0.07 mol), under nitrogen, were added dropwise (15 min) fumaryl chloride (3.78 ml, 0.035 mol) dissolved in ether ( io ml). The black mixture was stirred for 5 minutes at -10 ° C and for 10 minutes at room temperature. Charcoal was added and the reaction mixture was filtered on a Celite pad. The filtrate was washed with sodium hydrogen carbonate 1% brine (1: 1, 150 ml). The aqueous phase was back-extracted with ether (30 ml). The ether solutions were combined, washed with brine, dried over sodium sulfate, filtered and concentrated under reduced pressure to give a brown solid. This compound was purified on a silica gel pad (30 g, 4x5 cm) with benzene 20 (300 ml) as eluent to give an oil (4.855 g, 77%) which solidified on standing: m.p. 33-34 ° C.

Analysis calculated for ^ 14 ^, ^ ^, ^^ ^^, 2: C, 53.12; H, 8.91;

Found: C, 53.35; H, 8.91.

25 (CDCl 3) δ: 6.78 (2H, s, C = CH), 4.26 (4H, m, CH 2 -O), 1.03 (4H, m, CH 2 -Si) and 0.06 ppm (18H, s, (C 2 Si); v: 1710 (C = O of ester), 1643 (C = C), 1267, 1258, 862 and 840 cm 2 (Si-C).

Trimethyl silylethyl, glyoxylate hydrate 4.

o 11 ^ sitar) 3 3 11 o fH 2-Si (CH, l, (CH313S1 '^' J [2> ICH3> 2S 2 35

DK 161970 B

79

A solution of di-O-trimethylsilylethyl fumarate (37 g, 0.117 mmol) in methylene chloride (1.1 L) was ozonated at -78 ° C until a blue color was maintained. Excess ozone was excreted by nitrogen and dimethyl sulfide (2.57 ml, 0.351 mol) was added. The solution was allowed to gradually reach a temperature of 23 ° C. The reaction mixture was diluted with carbon tetrachloride to 2 liters and washed with 1% aqueous solution of sodium carbonate (500 ml). The organic phase was dried over sodium sulfate, filtered on Celite and evaporated (~ 25 ° C) to dryness to give 43.9 g of title compound (97%); ir 10 (pure) v-3450 (-0H), 1740 (ester, 1255, 860 and 840 cm -1) (Si-C). max 1- (1-trimethylethyl silyl ethyl-2'-hydroxy-2 ') -acetate) -4-triethyl thio-2-azetidinone STr STr CH (OH) _. r - f I-1 CO y ^^ SlC 3 ---->

I 1 CV Δ J — N OH

O γ SilCHj) 20

Trimethylsilylethyl, glyoxylate hydrate (4,000 g, 11.6 mmol) and 4-tritylthio-2-azetidinone (4.8 g, 24.96 mmol) were refluxed in benzene (25 ml) in a Dean Stark condenser under nitrogen for 24 hours. . The solvent was evaporated under vacuum. The product was chromatographed on a sieve 1 in a pillar column (450 g, 8.5 x 14.5 cm) and eluted with ethyl acetate: methylene chloride (1:19) until the title compound started to come out (-1.5 liters) and then with ethyl acetate: methylene chloride (1: 9, 2 liters). The fractions containing the title compound were combined and evaporated to dryness to give 5.415 g (89%) of the title compound. W (CDCl 3) 7.80 to 6.70 (15H, m, trityl), 5.23 and 4.90 (1H, 2s, HC-O), 4.50 to 4.10 (3H, m, H- 3 and O-CH 2), 2.60 (2H, m, H-2), 0.95 (2H, m, CH 2 -Si and 0.1 ppm (9H, s, Si-CH 2); ir (CHCl v: 3520 (-0H), 1765 (C = 0 of β-lactam), 1740 (C = 0 ~ oo max-35 of ester), 1595 (CH, aromatic), 1257, 860 and 840 cm 1 (C-Si).

80

DK 161970 B

1- (β-trimethyl silylethyl-2'-chloro-2'-acetate) -4-trityl thio-2-azetidinone STr

_ .STr S0C12 --S

5 I pyridine * ._ti Cl I ✓ '"v / 3 3 c0 CO 2 2 10

A solution of thionyl chloride (0.74 ml, 10.37 mmol) in dry THF (9 ml) was added dropwise with stirring to a solution of 1- (γS-trimethyl silylethyl-2'-hydroxy-2'-acetate) -4-Triethyl thio-2-azetidone (4.9 g, 9.37 mmol), pyridine (0.84 mL, 10.38 mmol) and dry THF (40 mL) at -15 ° C nitrogen atmosphere. The mixture was stirred at -15 ° C for 2 hours. The precipitate was removed by filtration on a Celite pad and washed with benzene (50 ml). The filtrate was evaporated in vacuo at 30 ° C. The residue was dissolved in benzene (100 ml), treated with charcoal and filtered through a Celite pad. Evaporation of the solvent gave a residue which was purified through a silica gel pad (100 g, 4.7 x 11 cm): hexane-benzene (1: 1, 400 ml), ether-benzene (1:19, 1 liter). Evaporation of the relevant fractions gave 4.64 g of the title compound (92%). * Hmr (CDCl 3) S: 7.30 (15H, m, aromatic H), 5.77 and 5.43 (1H, 2s, CH-Cl), 4.7 to 4.2 (3H, m, H- 4 and 25 CH 2 -O), 2.85 to 2.50 (2H, m, H-3), 1.15 (2H, m, CH 2 -Si) and 0.06 ppm (9H, s, Si-CH -); ir (pure) i / v: 1760 (C = O), 860 and 840 cm 2 (C-Si).

1- (R) trimethylsilylethyl-2'-tri phenylphosphoranylidene-2'-acetate) -30 -4-trityl thio-2-azetidinone • 4 STr _ JSTr Φ3Ρ - ^ s— N r.cl 2,6-lutidm qJ I ^ Ρψ 5i (CH) «^ Y ^ -SUCH3'3 lo, · ^ 33 35 to2 '^ 2/81

DK 16197 0 B

A dioxane (20 ml) solution of the above chlorazetidinone (4.12 g, 7.568) was treated with triphenylphosphine (2,209 g, 8.424 mmol) and 2.6-1utidi n (0.98 ml, 8.424 mmol). 3.5 hours. The cooled solution was filtered and the white solid was washed with THF. The filtrate was evaporated to dryness. The residue was purified on a silica gel column (200 g, 4 x 31 cm) using ethyl acetate-hexane (3: 7, 1 liter; 7: 3, 1 liter) to give the title phosphorane (4.836 g, 83% ). ir (film) γ: 1755 (C = 0), 1615 in max (phosphorane), 850 and 830 cm -1 (Si-C).

Analysis calculated for C CH ^ NONO P PSSi: C, 73.89; H, 6.07; N, 1.81 Found: C, 72.18; H, 6.08; N, 1.83.

Silver 1- (ff-trimethylsilylethyl-2'-tri phenylphosphoranylidene-2'-acetate) -2-azetidinone-4-thiolate STr I + + AgNO3 + (nBu) 3N + CF 2 ° 2 ° 2 S *, I ^SitCH) CO S ^ 3 3 2 25 1 - ([J-trimethylsilylethyl-2'-tri phenylphosphoranylidene-2'-acetate) - -2-azetidinone (7.64 g, 10 mmol) was dissolved in ether (60 ml). An aqueous solution of silver nitrate (0.5 m, 80 ml, 40 mmol) was added followed by rapid addition (1 minute) of a solution of tributylamine (3 ml, 12.58 mmol) and trifluoroacetic acid (0.154 ml, 0.2 mmol) in ether (20 ml). The mixture was stirred mechanically for 19 minutes. The precipitate was filtered, purified with ether (200 ml), triturated in water (70 ml), filtered again and purified with ether (100 ml). The light brown solid was dried under vacuum (water aspirator 10 min and pump 65 min) to give the title compound (6.42 g), ir (CHCl 3) i / max: 1862 * 35 (C = 0, 1630 (phosphorane)) , 860 and 840 cm 2 (Si-C).

82

DK 161970 B

Example 22

Sodium and potassium salts of 6-formamidomethylT-2-methylpenem-3-carboxylic acid trans-1- (t-butyldimethylsyl) -3-methanesulfonyl oxymethyl-4-tritylthio-2-azetidinone

OH H H

HH .. T!> SC <}> 15 __HS0 II] J- »I '' silCH) ° ^ Si (CH) \ 32 \ 32 t-Bu t-Bu 20 A solution of trans-1- (t-butyldimethylsilyl) ) -3-Hydroxymethyl-4-tritylthio-2-azetidinone (8.0 g, 16.36 mmol) in dichloromethane (50 ml) was heated at 5 ° C with methanesulfonyl chloride (1.4 ml, 18 mmol) in dichloromethane ( 10 ml) and triethylamine (2.5 ml, 18 mmol). Stirring was maintained for 1 hour under N 2. Then, the solution was washed successively with cold 1 N hydrochloric acid, 1 M sodium bicarbonate and brine, dried (MgSO 4) and evaporated in vacuo. The residue (mixture of hydroxy and mesylate cpd) was again treated as before to form the mesylate (90 g, 97%) as an amorphous solid. It was used as such in the next step without further purification. The analytical sample was recrystallized from methylene chloride, m.p. 167-168 ° C. IR (pure) i: 1755 cm55 1. 1 Hmr (CDCl 3) S: 7.3 (15H, * m), 4.4 (1H, d, J = 2 Hz), 3.9 (1H, dd, J = 8 Hz, 4 Hz), 3.2 (2H, bs), 2.8 (3H, s), 0.95 (9H, s) and 0.3 ppm (6H, s).

35 83

DK 161970 B

Trans-3-methanesulfonyloxymethyl-4-tritylthio-2-azetidinone and trans-3-azidomethyl) -4-tritylthio-2-azetidinone

5 jyscd?> Sc <f> H H

^ π 3 _> -> ^ - r 3_. »Ri-f> cr v, J— n. Li

SUCH,) o H H

T-Bu 10 A solution of trans-1- (t-butyldimethylsilyl) -3-methanesulfonylmethyl-4-tritylthio-2-azetidinone (21.0 g, 37.0 mmol) in HMPA (90 ml) cooled in an ice bath and treated with sodium azide (2.7 g, 41.2 mmol) in 10 µl (10 mL). The reaction mixture was stirred at room temperature for 1 hour, diluted with ethyl acetate, washed with (5 x 100 ml), dried (MgSO 4) and evaporated in vacuo. Trans-3-methanesulfonyloxymethyl-4-triethylthio-2-azetidine is diluted with HMPA (90 mL), treated at room temperature with sodium azide (2.7 g, 41.2 mmol) in HgO (10 mL), heated at 60 ° C for 2 hours and triturated with cold water. The crude azide was diluted with benzene-ether (5: 1) and washed with water (5 x 20 ml). Evaporation of the solvent followed by crystallization from ether gave 18.0 g (77%) of azide as a white solid. The analytical sample was recrystallized from CH 2 Cl 2 / ether, m.p. 174-5 ° C.

Calcd. For C₂ ^H₂₂O₂: 25 Calculated: C: 68.97, H: 5.03, N: 13.99,

Found: C: 68.78, H: 5.00, N: 14.16.

IR (nujol) v: 2100, 1765 cm cm ", δ Hmr (CDCl1): δ: 7.35 (15H, m), max δ 4.75 (1H, bs), 4.4 (1H, d, J = 2 Hz) and 3.1 - 3.7 ppm (3H, m).

Trans-3-aminomethyl-4-trityl thio-2-azetidone non 4 N3 \ --- + J_1 35 o nh o

DK 161970 B

84 ΤΠ A solution of trans-3-azidomethyl-4-tritylthio-2-azetidinone (10.0 g, 47.5 mmol) in dry methanol (500 ml) was added ammonium chloride (19.0 g) and zinc powder (1.0 g) and the suspension was stirred at room temperature for 5 hours. The reaction mixture was filtered and evaporated. The residue is partitioned between 1N hydrochloric acid and benzene. The aqueous layer was made basic with 1M sodium bicarbonate and extracted with methylene chloride. The extracts were washed with brine, dried (MgSO 4) and evaporated in vacuo. The crude amine was crystallized from ether, 14.05 g (79%); mp. 139-9 ° C.

Analysis for C23H22N2O2.1 / 4 CH2 Cl2:

Calculated: C: 70.56, H: 5.73, N: 7.08,

Found: C: 70.68, H: 5.94, N: 7.27.

IR (CHCl3) ν: 3400 and 1760 cm "1. 1 Hmr (CDCl13) δ: 7.35 (15H, m), 5.15 (1H, m), 4.3 (1H, bs), 2.7 - 3.5 (3H, m) and 1.3 ppm (2H, m).

Trans-3-phthalimidomethyl-4-tritylthio-2-azetidinone o

li h H

20 η h ✓ΟγΑ s "A ^ sc <i) 3> / tp -.

25 A solution of trans-3-aminomethyl-4-tritylthio-2-azetidinone (13.9 g, 37.2 mmol) and N-carbethoxyphthalimide (8.3 g, 37.9 mmol) in benzene (200 ml) was heated at reflux for 15 hours. The solvent was evaporated in vacuo and the residue crystallized from ether to give 17.4 g (93%) of the title compound; mp.

172-3 ° C.

Analysis for C

Calculated: C: 73.78, H: 4.79, N: 5.55,

Found: C: 73.92, H: 4.87, N: 5.49.

IR (CHCl3) v 1770 and 1715 cm -1. HHmr (CDCl1) δ: 7.8 (4H, όΙΐΙΙΐΙΧ, 35 m), 7.3 (15H, m), 4.45 (1H, d, J = 2 Hz), 3.3 - 4, 1 (3H, m) and 3.3 -4.6 ppm (1H, m).

5 85

DK 161970 B

Trans-3-phthalimidomethyl-1- (paranitrobenzyl-2'-hydroxy-2'-acetate) -4-tritylthio-2-azetidinone 0. (f NH

CO PNB

A mixture of trans-3-phthalimidomethyl-4-tritylthio-2-azetidinone (17.4 g, 34.52 mmol), paranitrobenzylglyoxylate, hydrate (9.4 g, 41.4 mmol) and triethylamine (4, 8 ml, 34.5 mmol) in tetrahydrofuran (250 ml) was stirred at room temperature for 20 hours. The reaction mixture was evaporated in vacuo and the residue treated with charcoal in benzene. Evaporation of the solvent gave the crude hydroxyglyoxylate (25 g, quantitative) as an amorphous solid. It was used in the next step without further purification. IR (CHCl3) v: 1770 and 1715 cm -1. 6 Hmr (CDCl 3) S: 8.1 (2H, d, J = 9 Hz), 7.55 (3H, d, J = 9 Ha), 7.3 (19H, m), 5.0 - 5.4 (2H, bs), 4.3 - 5.0 (2H, m) and 2.8 - 3.8 ppm (4H, m).

Trans-3-phthalimidomethyl-1- (paranitrobenzyl-2H-chloro-2'-acetate) -4-tritylthio-2-azetidinone

Hf CO PNB

CO PNB 2 2 30

To a cooled (ice bath, 0 ° C) solution of trans-3-phthalimidomethyl-1- (paranitrobenzyl-2'-hydroxy-2'-acetate) -4-triethylthio-2-azetidinone (25 g, 35 mmol ) in tetrahydrofuran (150 ml) was added dropwise a solution of thionyl chloride in tetrahydrofuran (46 ml, 46 mmol) followed by a 35 M solution of pyridine in tetrahydrofuran (46 ml, 46 mmol). The reaction mixture was stirred at room temperature for 20 minutes, diluted with petroleum ether (50 ml) and filtered over a Celite / charcoal bed. The solvent was evaporated in vacuo to give 86

DK 161970 B

chlorazetidinone (26 g, quantitative) as an amorphous solid. It was used in the next step without further purification. IR (CHCl3) niax1 1775 and 1720 cm -1. iHmr (CDCl3) S: 8.12 (2H, d, 0 = 9 Hz), 7.60 (2H, d, ΰ = 9 Hz), 7.3 (19H, m), 5.25 (2H, m ), 4.7 - 5.4 δ (1H, m), 4.55 (1H, bs), and 3.3 - 4.0 ppm (3H, m).

Trans-3-phthali in domethyl -1- (paran trobenzyl-2β-tri-phenyl-phosphoranylidene-2β-acetate) -4-tritylthio-2-azetidinone

CO PNB CO PNB

2 2 15

A mixture of trans-3-phthalimidomethyl-1- (paranitrobenzyl-2 H -chloro-2'-acetate) -4-tritylthio-2-azetidinone (26 g, 35.5 mmol), triphenylphosphine (10.25 g, 39.1 mmol) and 2,6-lutidine (4.6 ml, 39.1 mmol) in dioxane (200 ml) were heated at 100 ° C for 20 hours. The reaction mixture was filtered over Celite and evaporated. The residue was chromatographed on a silica gel column (350 g) eluting with benzene to benzene / ether (1: 1) to give the phosphorane (21 g, 62%) as a white solid. IR (CHCl3) p: 1750 and 1710 cm "". 1 Hmr (CDClC) δ: 7.4 (38H, m) 4.8 - 5.4 (3H, m), 4.6 (2H, m) and 3 , 7 ppm (1H, bs).

Trans-3-phthalamidomethyl-1- (paranitrobenzyl-V-triphenylphosphoranylidene-2β-acetate) -4-tritylthio-2-azetidinone (§xVH'sc * 3 - ► © Vtf

C02P.NB

A cooled (ice bath) suspension of trans-3-phthalimidomethyl-1- (paranitrobenzyl-2β-triphenylphosphoranylidene-2β-acetate) -4-tritylthio-2-azetidinone (18.02 g, 18.83 mmol) in tetrahydrofuran (30 ml), water t 35

DK 161970 B

87 (30 ml) and acetone (30 ml) were treated dropwise with sodium sulfide (4.97 g, 20.7 mmol) in acetone / water 1: 1 (30 ml) and heated to reflux for 8 hours. The reaction mixture was diluted with water, acidified with 1N hydrochloric acid and extracted with dichloromethane.

The organic extracts were washed with brine and evaporated in vacuo to give 17.1 g (88%) of the title compound as an amorphous pale yellow solid. It was used in the next step without further purification. IR (pure) µ: 3150 - 3600, 1750 and 1700 cm cm ’. x Hmr (CDCl 3) δ: 7.4 (38H, m) and 3.3 - 5.5 ppm (8H, m).

10

Trans-S-L-phthalisoimidomethyl fparanitrobenzyl ^ '- triphenyl-phosphoranylidene-2'-acetate) -4-tritylthio-2-azetidinone

(θ ') Η H

15 fl i? .Sc *, W A

3 __ ^ CO 2 H / -ΝγΡΦ1

CO PNB CO PNB

2 in 20 A solution of trans-S-phthalimidomethyl-1-iparanitrobenzyl 4'-triphenylphosphoranylidene-2'-acetate) -4-triethyl thio-2-azetidinone (17.1 g, 17.54 mmol) in dichloromethane ( 125 ml) was treated dropwise at room temperature with N, N'-dicyclohexylcarbodiimide (3.62 g, 17.54 mmol) in dichloromethane (30 ml). The solution was filtered over Cel in tea and evaporated to give title compound (18.23 g, quantitative) as an oil. It was used in the next step without further purification.

IR (neat) v: 2110, 1755, and 1710 cm 1 m (m³) (CDCL ·) δ: 7.5 ΗΙ αΧΧ (38H, m), 4.6 - 5.3 (4H, m), and 3, 9 ppm (2H, bs).

Trans-3-aminomethyl-1- (paranitrobenzyl-2β-triphenylphosphorylidene-2'-acetate) -4-triethyl thio-2-azetidinog

35 (f "V" 3 To PNB

CO PNB

88

DK 161970 B

A solution of trans-3-phthalisoimidomethyl-1- (paranitrobenzyl-2'-triphenylphosphoranylidene-2'-acetate) -4-tritylthio-2-azetidinone (5.9 g, 6.16 mmol) in tetrahydrofuran (40 ml) , cooled to -20 ° C, was treated dropwise under Ng with hydrazine (0.2 mL, 6.16 mmol), and stirring was maintained for 30 minutes. The reaction mixture was acidified with 1N hydrochloric acid and washed with ether; the aqueous phase was made basic with 1M sodium bicarbonate and extracted with methylene chloride. The organic extracts were washed with brine, dried (MgSO 4) and evaporated. The residue was purified on a silica gel column 10 (60 g) eluting with ether to ethyl acetate to give * 3.38 g (66%) of the aminophosphorane as an amorphous solid. IR (CHCl 3) δ: 1730, 1710 cm 1 1, mr (CDCl1) δ: 6.5 - 8.1 (34H, m), 3.8

ΪΤιαΧ O

5.3 (6H, m) and 0.9 - 1.9 ppm (2H, m).

Trans-3-formamidomethyl-1- (paranitrobenzyl-2'-tri-phenylphosphoranylidene-2'-acetate) -4-tritylthio-2-azetidinone 3-A V * 3

io2PNB CO ^ PNB

To a cooled (ice-bath) solution of trans-3-aminomethyl-1- (para-25-trobenzyl-2'-tri-phenyl-phosphoranylidene-1-acetate) -4-triethyl-o-2-aze-tidinone (5, 0 g, 6.04 mmol) in dichloromethane (50 ml) was added dropwise under a solution of acetic acid formic anhydride (600 mg, 6.8 mmol) in dichloromethane (5 ml) followed by a solution of tri ethylamine (1 ml, 7 mmol) in dichloromethane (2 ml). Stirring was continued for 30 minutes-30 hours. The solution was washed successively with 1N hydrochloric acid, water, 1H sodium bicarbonate and brine. The organic layer was dried (MgSO 4), evaporated and the residue chromatographed on a silica gel column (50 g). Elution with ether to ethyl acetate gave 2.0 g, (39%) of the formamide as an amorphous solid. IR (CHCl3) 1740, 1685 and 1620 35 cm -1 1 Hmr (COCl3) S: 6.6 - 8.2 (35H, m) and 2.5 - 5.3 ppm (7H, m).

t

DK 161970 B

89

Trans-silver-3-formamidomethyl-1- (paranitrobenzyl-2'-tri-phenyl-phosphoranylidene-2'-acetate) -2-azetidinone-4-thiolate J — N. A solution of trans-3-formamidomethyl-1- (paranitrobenzyl-2'-triphenylphosphoranylidene-2'-acetate) -4-tritylthio-2-azetidinone (550 mg, 0.64 mmol) in dichloromethane (10 ml) was evaporated. to dryness and diluted with hot methanol (20 ml). The solution was stirred at 60 ° C and treated with a preheated (60 ° C) solution of 0.15M silver nitrate in methanol (5.7 mL, 0.86 mmol) followed by a solution of 1.5M pyridine in methanol ( 0.57 ml, 0.86 mmol). The creamy solution was stirred at room temperature for 30 minutes, then in an ice bath for 2 hours. The solid was filtered, washed with cold methanol and ether and dried to give 300 mg (65% of the silver salt as a beige solid. It is used in the next step without further purification).

Trans-4-acetylthio-3-formamidomethyl-1- (paranitrobenzyl 2'-tri-phenylphosphoranylidene-acetate) -2-azetidinone 25 η Γ - -H J_il JP0, c / -N

T CO PNB

CO.PNB 2 30 2 4.

To a cooled (ice-bath) solution of trans-silver-3-formamidomethyl-1- (paranitrobenzyl-2'-tri-phenylphosphoranylidene-2'-acetate) -2-azetidi-non-4-thiolate (800 mg, 1.11 in dichloromethane (10 ml) was added dropwise under N2 a solution of 1M acetyl chloride in dichloromethane (1.33 ml, 1.33 mmol) followed by a solution of 1M pyridine in dichloromethane (1.33 ml), 1 , 33 mmol). The solution was stirred in a cold bath for 1 hour and then filtered over Celite. The filtrate was washed 90

DK 161970 B

successively with 1N hydrochloric acid, water, 1M sodium bicarbonate and brine, and the organic layer is dried (MgSO4) and evaporated. The residue was purified on a silica column (5.0 g) and eluted with ethyl acetate to 10% methanol in ethyl acetate to give 450 mg (62%) of the title compound: IR (CHCl 3: 1755, 1685 and 1620 cm -1Hmr (CDCl3) S: 8.18 (2H, d, J = 9 Hz), 7.0 - 8.0 (20H, m), 6.75 (2H, d, J = 9 Hz) , 6.3 (1H, m), 5.5 (1H, m), 5.2 (2H, bs), 4.9 (1H, bs), 3.6 (1H, m), 3.0 ( 1H, m) and 2.2 ppm (3H, two s).

10 Paranitrobenzyl-6-formamidomethyl-2-methylpenem-3-carboxylate H J_I Ρφ3 * 15 o 3

CO PNB

A solution of trans-4-acetylthio-3-formamidomethyl-1- (paranotrobenzyl-2'-tri phenylphosphoranylidene-2'-acetate) -2-azetidinone (450mg, 0.686mmol) in toluene (10ml) was heated. under reflux for 12 hours. Concentration and purification on a silica column eluting with ether to 10% methanol in ether gave 100 mg (39%) of the penemen as an amorphous solid. IR (CHCU) vm '. 1780 and 1690 cm- *. 1 Hmr (CDCl 3) S: 8.2 (2H, d, J = 9 Hz), 8.2 (1H, s), 7.6 (2H, d, J = 9 Hz), 6.9 (1H, m), 5.55 (1H, s), 5.35 (2H, 2S), 3.3 - 4.1 (3H, m) and 2.33 ppm (3H, s).

Sodium and potassium salts of 6-formamidomethyl-2-methylpenem-3 - carboxylic acid 30

A

Η H

H H O

V1 +> ch3 ->

3 0 Λοβ, β-ο, P

Co2pnb 2:

DK 161970 B

91

A mixture of paranitrobenzyl-6-formidomethyl-2-methylpenem-3-carboxylate (80 mg, 0.21 mmol), palladium-on-Celite (30%, 100 mg) tetrahydrofuran (10 ml), ether (25 ml) and 0.05M buffer solution pH 7 (4.46 mL, 0.223 mmol) was hydrogenated on a Parr shaker 5 at an initial hydrogen pressure of 45 psi for 3 hours. The catalyst was removed by filtration on Cel ite and washed with water. The filtrate and washings were combined and the phases separated. The aqueous phase was washed with ether (3 x 15 ml) and lyophilized. The crude solid was purified by hplc to give 18 mg of a mixture of the sodium 10 and the potassium salts. UV (H90) X: 299 (e 4933), 259 (€ 4094). IR

(nujol) »/: 3100 - 3650 and 1755 cm -1. Hmr (020) δ: 8.15 (1H, s), 5.53 (1H, d, J = 1.4 Hz), 4.0 (1H, m), 3.74 (2H, d, J = 5

Hz), 3.25 - 4.25 (1H, s), 5.53 (1H, d, J = 4 Hz), 4.0 (1H, m), 3.74 (2H, d, J = 5 Hz), 3.25 - 4.25 (1H, m) and 2.27 ppm (3H, s).

15 4 92

DK 161970 B

Example 23

Sodium and potassium salts of (rR, 5R, 6S and 1'S, 5S, 6R) 6- (r-hydroxy - Γ-propyl) -2-methylpenem-3-carboxylic acid (isomer B)

5 HQ, H

(1 / R, 3S, 4R and rS, 3R, 4S) 1-t'-butyldimethylsilyl-5-formyl-oxy-1'-propyl) -4-tritylthio-2-azetidinone (isomer) B)

OH HCO H, ET N OCHO

^^ STr DMAP, Ac20

X- N CH.Cl J-N

° -SiMe2 2 2 0 X.siM ^ 20 4-Dimethylaminopyridine (DMAP) was prepared according to a) H.C. Brown et al., Org. Synth. Collect. Vol. 5, 977 (1973) and b)

Helmet Vorbruggen et al., Angew. Chem. Int. Ed., 17, 569 (1978). Course of action:

To a cooled (0 ° C) solution of (1'R, 3S, 4R and 1'S, 3R, 4S) 25 1-t-butyldimethylsilyl-3- (1'-hydroxy-1'-propyl) -4-tri To thi o-2-azeti di-non (isomer B) (3.612 g, 7 mmol) in CH 2 Cl 2 (50 mL) was added Et 2 N (4.48 mL, 35 mmol), HCO 2 H (0.63 mL, 16, 8 mmol) and DMAP (0.854 g, 7 mmol) followed by the dropwise addition of acetic anhydride (7.14 g, 70 mmol). The clear yellow solution was stirred at -40 ° C, 30 and milky mixture. It was poured onto ice-ΙΝ HCl (pH 6) and the layers separated. The CH 2 Clg solution was washed with 1M NaHCO 3 and brine. It was dried (Na 2 SO 4) and evaporated to dryness to give 3.8 g of a solid residue. This was treated with pentane and filtered to give 3.7 g of a white solid (96.8%). Mp. 125-27 ° C. IR (pure) δ ax: 1720 (H-C-) and

. ISLAND

1750 cm "1 (ε-lactam). Hmr (CDCl13) δ: 7.1 (H, s, H - (-), 6.8 - 7.7.93)

DK 161970 B

(15H, m), 4.8 (H, m), 4.05 (H, d, J = 1.5), 3.7 (H, m, J = 1.5, J = 7), 1 , 4 (2H, m), 0.95 (9H, s), 0.8 (3H, t) and 0.1 ppm (6H, s).

Calculated: C: 70.42, H: 7.20, N: 2.57,

Found: C: 70.20, H: 7.33, N: 2.73.

(1'R, 3S, 4R and 1'S, 3R, 4S) 3- (Γ-Formyloxy-1'-propyl) -4-triethyl-thio-2-azetidinone (isomer B)

OCHO

OCHO I

J> STr _ ^ - * STr

- [HMPT. IN

I + NaN, "-" Y — N

A – N 3 10% H O Cr

CT ^ SiMe 2 H

15 2

Course of action:

To a cooled (ice bath) solution of (3.7 g, 6.77 mmol) in HMPT (40 ml) containing 10% HgO was added NaN3 (0.91 g, 14 mmol). The mixture was stirred at room temperature for 1.5 hours. It was poured into ice rim (200 ml) and extracted with ether (4 x 40 ml). The ether solution was diluted with petroleum ether and washed thoroughly with water and brine to remove HMPT. It was dried (Na 2 SO 4) and evaporated to dryness to give 2.92 g of a thick colorless oil.

25 (Quantitative yield), m m (CDCl 3) S: 8.1 (H, HC-, S), 7.1 - 7.7 (15H, m, -STr), 5.23 (H, m, J = 7), 4.38 (H, d, J = 2.5), 4.3 (H, -NH), 3.35 (H, dd, J = 2.5, J = 7), 1 , 75 (2H, m) and 1.0 ppm (3H, t).

30 4 35

DK 161970B

94 (1'R, 3S, 4R and 1'S, 3R, 4S) 3- (r-Formyloxy-1'-ethyl) -1- (para-nitrobenzyl-211-hydroxy-2'-acetate) -4-tritylthio -2-azetidinone (isomer B)

OCHO OCHO

1_> STr A_> STr I f PNB GLYOXYLATE I i - \ H Et ^ N / THF ^ \ ^ / ΟΗ

CO PNB

10-2 Procedure:

A mixture of 3- (r-formyloxy-r-propyl) -4-tritylthio-2-azetidinone (isomer B) (2.9 g, 6.77 mmol), PNB glyoxylate (1.59 g, 7 mmol) ), 15 EtgN (5 drops) and NagSO 4 (anhydrous, 5.0 g) in THF (50 ml) were stirred at room temperature for 18 hours. It was filtered and evaporated to dryness to give an amorphous solid in quantitative yield (4.33 g). 1 Hmr (CDCl 3) δ: 8.2 (2H, d), 7.1 - 7.8 (18H, m), 5.2 (2H, d), 4.9 (H, m), 4.65 and 4.3 [H, 4.65 (1/2 H, s) 4.3 (1/2 H, s)], 4.2 - 4.3 (H, d, 1/2 H at 4, 2, 1/2 H at 4.3), 3.65 (H, m), 1.4 (2H, m) and 0.8 ppm (3H, t).

(1'R, 3S, 4R and 1'S, 3R, 4S) 3- (r-Formyloxy-r-propyl) -1- (para-nitrobenzyl-2ll-chloro-2 "acetate) -4-tritylthio-2- azetidinone 25 (isomer B)

OCHO OCHO

^ STr STr

j Py / THF

rJ-N \ ^ ° H SOC1 / THF ς /

30 T 2 I

CO PNB CO PNB

2 4..2

Course of action:

To a cooled (ice-salt bath) solution of the above-mentioned 35 glyoxylate (4.3 g, 6.77 mmol) and 1M Py / THF (8 mL, 8 mmol) in dry THF (30 mL) was added dropwise. 1 H SOClg / py (8 mL, 8 mmol) The resulting solid mixture was stirred at the above temperature for 1 hour, diluted with benzene (30 mL) and stirring continued;

DK 161970 B

95 was set for 20 minutes. It was filtered over Celite charcoal and the filtrate was evaporated to dryness to give 4.1 g of an amorphous solid

ISLAND ISLAND

's // -I

(92%). IR (pure) v: 1720 (H-C-), 1750 (-C-OPNB) and 1780 cm

flldX

4 ° (β-lactam). mr (CDCl3) S: 8.25 (2H, d), 7.8 (H, s, HC-), 7 - 7.75 (17H, m), 5.25 (2H, d), 5, 0 (H, m), 4.6 (H, s), 4.4 (H, d), 3.7 (H, m), 1.6 (2H, m) and 0.9 ppm (3H, t) .

10 (TR, 3S, 4R and rS, 3R, 4S) S-U'-Formyloxy-1'-propyl-1-eparitnitrobenzyl-211-triphenylphosphoranylidene-2 "acetate) -4-tritylthio-2-azetidinone (isomer B)

Ρ ° Η0 OCHO

15 «3p aioxane ^ fSTr O lutidine \ ^> ΡΦ3

C02PNB lo PNB

Method:

A mixture of the above-mentioned chlorine compound (4.0 g, 6.07 mmol) φ ^ (1.834 g, 7 mmol) and lutidine (0.749 g, 7 mmol) in dioxane (40 ml) was heated at 100 ° C (oil bath ) for 2 days. It was cooled, diluted with ether and washed successively with cold solution of 1N HCl, 1M NaHCO 3 and brine. The organic solution was dried (Na 2 SO 4) and filtered over Celite charcoal. Therein it was evaporated to dryness to give an oil which was chromatographed on SiO 2 (Act. 1, 200 g) and eluted with benzene ether to give 2.60 g of title compound as an amorphous solid (48.45% ). IR (pure) 30 "max" 1720 (H-c- ° -> ° 9 1750-1760 cm -1 (-CO2PNB and β-Octam).

5 96

DK 161970 B

(1'R, 3S, 4R and rs, 3R, 4S) 4-acetylthio-3- (r-formyloxy-r-propyl) -1- (paran in trobenzyl-2 "-tri phenylphosphoranyli den-2" - acetate) -2-azetidinone (isomer B)

OCHO QCHO

STr JyYSAg

10 CO PNB CO PNB

Δ 2

OCHO

15 Ν \ ^ ΡΦ3

C02PNB

Method:

A hot solution (60 ° C) of 0.15M AgNO 3 -CH 2 OH (8.7 mL, 1.3 mmol) was added to a mixture of the aforementioned phosphorane (0.88 g, 1 mmol) and pyridine (0.103 g, 1.3 mmol) in MeOH (5 ml) heated to 60 ° C. The mixture was stirred at room temperature for 15 minutes and at 0 ° C for 2 hours. It was filtered and washed with cold MeOH to give 0.53 g of the silver mercaptide as a yellow solid (71%) which was used as such. To a cooled (ice-bath) mixture of the above-mentioned mercaptide (0.53 g, 0.71 mmol) and pyridine (0.079 g, 1 mmol) in CHgClg (10 ml) was added dropwise CHgCOCl (0.079 g, 1 30 mmol) in CHgCl2 (5 ml). After stirring at 0 ° C for 1 hour, the mixture was filtered. The filtrate was washed well with a cold solution of 0.5 M HCl, 0.5 M NaHCO 3 and brine. It was dried (Na 2 SO 4) and evaporated to dryness to give 0.43 g of an oil. (63%). IR (neat) -1 35 nm: 1700 - 1760 cm -1 (broad -C and β-lactam).

i 97

DK 161970 B

(rR, 3S, 4R and 1'S, 3R, 4S) and acetylthio-S-U'-hydroxy-r-propyl-1- (paranitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azetidinone (isomer B)

_ OCHO PH

Owslc U

in HCl / MeOH) I

3 θ · ^ -Νγ? Φ3 C02PNB co2pnb Procedure:

The above-mentioned formate (1.0 g, 1.45 mmol) in THF (10 ml) was treated at room temperature with HCl / MeOH (10 ml, prepared from 2 ml concentrated HCl and diluted with MeOH to a volume of 24 ml). . The mixture was kept at room temperature for 0.5 hours. It was basified with 1M NaHCO 3, extracted with EtOAc solution, washed with brine and dried (50 SO). It was evaporated to give 0.9 g of the crude title. This was chromatographed on S1O2 and eluted with ether and ether: EtOAc (1: 1) to give 0.6 g of pure title compound as an amorphous solid (62.5%).

1 Hmr (CDCl 3) δ: 8.25 (2H, d), 7.3 - 8.1 (17H, m, aromatic), 5.6 (H, m), 5.2 (2H), 4.9 (H), 4.4 (H, m), 2.3 (3H, SAc), 1.5 (2H, m) and 0.9 ppm (3H, t).

(1; R, 5R, 6S and rs, 5S, 6R) paranitrobenzyl 6- (Γ-hydroxy-Γ-propyl) -2-meth, ylpenem-3-carboxylate (isomer B)

OH OH

,, Of'*. - A ^ "CO PNB 2 2 *

Course of action:

The aforementioned phosphorane (0.2 g, 0.3 mmol) in toluene (45 ml) was heated to reflux and 5 ml of toluene was distilled off.

The resulting baking solution is evaporated for 6 hours. It was cooled and evaporated to dryness to give 0.2 g of an oil. This was chromatographed on SiO 2 and eluted with ether to give i

DK 161970 B

98 0.1 g of the title compound as a white solid. (87%). Mp. (pen-tan) 133-135 ° C. iHmr (CDCl3) i: 8.3 (2H, d), 7.6 (2H, d), 5.6 (H, d), 5.35 (2H, d), 4.15 (H,), 3.8 (H, g), 2.4 (3H, s, CH 2), 2.2 (H, OH), 1.7 (2H, m) and 1.05 ppm (3H, t).

Mixed K and Na salts of (rR, 5R, 6S and rs.5S.6R) 6- (r-hydroxy-Γ-propyl) -2-methylpenem-3-carboxylic acid (isomer R)

OH? H

15 'CO PNB CO (Wa + K) 2 2

Procedure: A mixture of the above ester (0.07 g, 0.185 mmol), 30% Pd-Celite (150 mg) and buffer solution (pH 7, 4 ml) in THF (15 ml), Et 2 O (25 ml) and deionized water (15 ml) were hydrogenated at an initial pressure of 48 psi for 4 hours. It was filtered over Celite and the layers separated. The aqueous layer was washed with ethyl acetate and then lyophilized to give 91 mg of a solid. IR (KBr) i / maxi 1780 (β-lactam) and 1650 cm -1 (wide, -CO2 ~). UV H2 O: 255 (£ 983) and 300 [e 1092).

X, 5 99

DK 161970 B

Example 24 (4'S, 5R, 6S and 4 / R) 5 $, 6R) -6- (2β, 2β-dimethyl-1,3,3-dioxolan-4'-yl) -2-methylpenem-3- carboxylic acid (Isomer B) 0 Λο2 4 (4 / $, 35.4R and 4R, 3R, 4S) -3- (2 /, 2'-dimethylM) -3 / -dioxolane-4-yl) - 4 ~ tri tyl thi o-2-azeti di non (Isomer B) O, _> STr O, _sST'r

Tj -¾_, ΓΓ J— N / HMPT-H O, 0 * ~~ u '"Si 2 * /> <30

The title compound was prepared as described in Example 51 for "Isomer C" from (4'S, 3S, 4R and 4R, 3R, 4S) -1- (t-butyl-dimethylsilyl) -3- ( 2 ', 2'-dimethyl-β, 3'-dioxolan-3'-yl) -4-tritylthio-2-azetidinone (Isomer E) (14.4 g, 25.8 mmol): yield 10.8 g, 24.3 mmol, 94.1%; 35 mp. 155 ° C (CH2 Cl2 ~ Et2 O); Rf 0.24 (hexanes: EtOAc = 2: 1); Hmr (CDCl3): 1.37, 1.40 (6H, 2s, di-Me), 3.23 (1H, dd, 03-4 = 2.5 Hz, J3 4, = 5Hz, H-3), 3.7-4.5 (4H, m, H-4 \ H-5 ', NH), 4.50 (1H, d, J = 2.5Hz, H-4) and 7.1-7.6 ppm (15H, m, aromatic Hs); ir (nujol) 100

DK 161970 B

3170 (NH) and 1745 cm -1 (C = O);

Analysis calculated for c27 H27 NO3 S: C, 72.78; H, 6.11; N, 3.14; S, 7.20; found: C, 72.16; H, 6.11; H, 3.14; S, 7.17.

5 (4'S, 3S, 4R and 4 / R, 3R, 4 $) - 3- (2 /, 2 H -dimethyl-1,3,3-dioxolan-4,1-yl-1- (p-nitrobenzyl) -2 "-hydroxy-2" acetate) -4-tritylthio-2-azetidinone (mixture of epimers at C-2 ") (Isomer B) 10 S ° PNB _ 15 Et3K / THF ^ CO PNB 2 20 Title past The latter was prepared as described in Example 51 for "Isomer C" from (4'S, 3S, 4R and 4 ^^, 45) -3 - ^, 2 ^ 11 ^ 1 ^ 1 - ^, 3 ^ -dioxolane-4 / - yl) -4-tritylthio-2-azetidinone (Isomer B) (10.8 g, 24.3 mmol): yield 15.8 g, 24.1 mmol, 99.3%); yellow foam; Rf 0.29 and 0.22 (benzene: Et 2 O + 1: 1); 1HMR (CDCl 3) δ: 1.28, 1.34 (2s, di-Me), 3.4-4.4 (m, H-3, H-4 ', H-5', H-2 ", OH), 4.39, 4.53 (2d, J = 2Hz, H-4), 5.15, 5.25 (2s, OCHgAr) and 7.1-8.3 ppm (m, aromatic Hs); ir (pure) i / max: 3440 (br, OH), 1760 (C = O), 1520, 1350 cm "1 (NO₂).

4 i

DK 161970 B

101 (4'S, 3S, 4R, and 4'R, 3R, 4 $) - 3- (2,2,2-dimethyl-r, 3β-dioxoanil-4'-yl) -1- (p-nitrobenzyl) 2 "-chloro-2" acetate) -4-tritylthio-2-azetidinone (mixture of epimers at C-2 ") (Isomer B)

0J—> i ^ OH ™ F

CO PNB CO PNB

10 2

The title compound was prepared as described in Example 51 for "Isomer C" from (4, S, 3S, 4R and 4'Rf3R, 4S) -3- (2 /, 2'-dimethyl-r, 3 / -15 -Γ, 3'-dioxolan-4'-yl) -1- (p-nitrobenzyl-2 "-hydroxy-2" acetate) -4-trityl-thio-2-azetidinone (Isomer B) (14.9 g , 22.8 mmol); mixture of epimers at C-2 "); yield 14.1 g, 20.9 mmol, 91.9%; yellow foam; Rf 0.52 (benzene: Et 2 O = 3: 2); Hmr (CDCl 3) S: 1 , 30, 1.38 (6H, 2s, di-Me), 3.4-4.5 (4H, m, H-3, H-4 ', H-5'), 4.57 (1H, d , J = 3Hz, H-4), 5.13 (s, H-2 "), 5.27 (s, 0CH + Ar) and 7.1-8.3 ppm (19H, m, aromatic Hs) ; ir (pure) v: 1780 cm (ε-lactam, ester).

ΐΠαΛ (4'S, 3S, 4R and 4, R, 3R, 4 $) - 3- (2, 2, -dimethyl-1, 3, -dioxolan-4, -yl) -1- (p-nitrobenzyl) 2 "-Triphenylphosphoranilidene-2" acetate) -25 4-tritylthio-2-azetidinone (Isomer B)

30 ci * ο ^ _ν ^ ρφ3

CO PNB 4 CO PNB

Title 1 was prepared as described in Example 51 for "Isomer C" from (4'S, 3S, 4R and S'R.SR ^ SJ-S - ^ '^' - dimethyl-1'.S'- -dioxolan-4'-yl) -1- (p-nitrobenzyl-2 "-chloro-2" acetate) -4-tritylthio-2-azetidinone (Isomer B) (14.0 g, 20.8 mmol; mixture of epimers at 102

DK 161970 B

C-2 "): yield 4.64 g, 5.16 mmol, 24.8%; mp 190-195 ° C (decomp., CH 2 Cl 2-Et 2 O); W (CDCl 3) S: 1.12, 1, 20, 1.27, 1.35 (4s, di-Me) and 7.0-8.1 ppm (m, aromatic Hs); ir (CH 2 Cl 2): 1750 cm -1 (β-lactam ester); Analysis calculated for Cg ^NN PS: C, 72.14; H, 5.27; N, 3.12; S, 3.57; found: C, 71.90; H, 5.57; N, 3.07; S, 3.56;

Rf 0.21 (benzene: Et 2 O = 1: 1).

10 (4'S, 3S, 4R and 4 # R, 3S, 4R) -Silver-3- (2 ', 2 H -dimethyl-r 2' - dioxolane - 4 '1) -1- (p-nitrobenzyl-2 "-Triphenyl phosphoranyl-iden-2" acetate) - 2-azetidinone-4-thiolate (Isomer B) 15

The title compound was prepared as described in Example 51 for "Isomer C" from (4'S, 3S, 4R and 4'R, 3S, 4R) -3- (2 ', 2'-dimethyl-1', 3'-di oxolan-4'-yl) -1- (p-nitrobenzyl-2 "-triphenylphosphoranyliene-2" acetate) -4-tritylthio-2-azetidinone (Isomer B) (1.00 g, 1.12 mmol): yield 580 mg, 0.760 mmol, 67.8%; mp. 129-135 ° C (decomp.) Ir (nujol) y: 1745 cm -1 (jS-lactam, ester).

(4 '$, 3S, 4R and 4'R, 3S, 4S) 3- (2', 2'-Dimethyl-1 '' -dioxolan'-yl) -30 -1 '- (p-ni trobenzyl-2 "-Tri phenylphosphoranylidene-2" acetate) -4- -acetylthio-2-azetidinone (Isomer B) *.

_> SAC

\ A> »SAg CH ^ coci / pyr. ^ (| ...

35 jn

° CO PNB

CO PNB 2 2 103

DK 161970 B

/

The title compound was prepared as described in Example 51 for "Isomer C" from (4'S, 3S, 4R and 4'R, 3R, 4S) silv-3- (2 ', 2'-dimethyl - Γ, 3'- dioxolan-4'-yl) -1- (p-nitrobenzyl-2 "-triphenylphosphoranylidene-2" acetate) -2-azetidinone-4-thiolate (Isomer B) (2.46 g, 3.22 mmol): Yield after purification by column chromatography (SiO 2 32 g, eluent 10% -50% EtOAc in CH 2 Cl 2 = 1: 1). 1 Hmr (CDCl 3) δ: 1.23, 1.27, 1.30 (3s, di-Me), 2.22, 2.33 (2s, SAc) and 7.3 - 8.3 ppm (m, aromatic Hs). IR (pure) i / 1755 (/ Mactam, ester) and 1695 cm

iTlaX

ester).

10 (4 / $, 5R, 6 $ and 4, 5 $, 6Β) p-nitrobenzyl-6- (2 ', 2 "-dimethyl-r, 3β-dioxolan-4'-yl) -2- methylpenem-3-carboxylate (Isomer B) 15X, _ / SAc O '··, - JV -' οΛν3

T CO PNB

co2pnb - 2 20. The title compound was prepared as described in Example 51 for "Isomer C" from (4'S, 3S, 4R and 4'R, 3R, 4S) 3- (2 /, 2 / -dimethyl-1 3 '- di oxolan-4'-yl) -1- (p-nitrobenzyl-2 "-tri phenylphosphoranylidene-2" acetate) -4-acetylthio-2-azetidinone (Isomer B) (200 mg, 0.286 mmol):

Yield 64 mg, 0.15 mmol, 53%, m.p. 151-2 ° C (CH 2 Cl 2 / Et 2 O); Rf 25 0.67 (benzene: Et 2 O = 1: 1). Hmr (CDCl 3) δ: 1.29, 1.38 (6H, 2 $, di-Me), 2.30 (3H, s, 2-CH 3), 3.6-4.4 (4H, m, H-6, H-4 ', H-5'), 5.00 - 5.18 - 5.28 - 5.46 (4H, ABq, -0CH2 Ar), 5.47 (1H, d, J = 1 , 5 Hz, H-5) and 7.42 - 7, 55 - 8.05 - 8.15 ppm (4H, A2 ', aromatic Hs). IR (pure) ymax 1785 cm "1 (l J-lactam) and 1710 cm’1 (ester). UV (EtOH) Am: 266 (e 13,300) and 314 m / ι (e 9,700).

ΠιαΧ

Analysis for c18 H20 N2 ° 7S: +

Calculated: C: 54.28, H: 4.79, N: 6.66, S: 7.63,

Found: C: 54.00, H: 4.75, N: 6.68, S: 7.61.

35 104

DK 161970 B

(4'S, 5R, 6S and 4 / R, 5 $, 6R) 6- (2'12 / -dimethyl) -r, 3β-dioxolan-4β-yl) -2-methylpenem-3-carboxylic acid ( Isomer B)! Xf> =

C02PNB c02H

The title compound was prepared as described in Example 51 for * "Isomer C" from (4, S, 5R, 6S and 4'R, 5S, 6R) p-nitrobenzyl-6- (2 ', 2' - dimethyl -Β, 3'-Dioxolan-4'-yl) -2-methylpenem-3-carboxylate (Isomer B) (79 mg, 0.19 mmol): Yield after recrystallization from Cl 2 Cl 2 - pentane 9 mg, 0.032 mmol , 17%; Rf 0.54 (acetone: HOAc = 5: 0.5).

1 Hmr (CDCl 3) δ: 1.35, 1.44 (6H, 2s, dl-Me), 2.37 (3H, s, 2-CH 3), 3.6 - 4.5 (4H, m, H -6, H-4 ', H-5') and 5.56 ppm (1H, brs, H-5).

IR (pure) v: 1785 cm 2 (1-lactam). UV (EtOH) Amav: 307 (e ϊϊιαΧ ΪΠαΧ 4300) and 262 m [i [e 3700).

20

EXAMPLE 25 2-Benzylmethylamino-methyl-penem-3-carboxylic acid

COOH

A (i 3-CH-7-N-CH COlNa + + (COCl) \ = / 2 χ \ 2 30 (I) (^ J> ^ "2 ^^ C" 2COCl (II)

To a suspension of 0.38 g (0.0015 mol) of sodium 3-benzyl-35-1,2,4-oxadiazol-5-one-4-acetate (I) * in 10 ml of methyl chloride containing 2 drops of DMF 0.13 ml (0.0015 mole) of oxalyl chloride was added at room temperature, causing the mixture to burst. The reaction mixture was stirred at room temperature for 1 hour. It formed /

DK 161970 B

'105

The NaCl was removed by filtration and the filter cake washed with several small portions of methylene chloride. The acid chloride (II) solution was used directly.

* K. Tak'acs and K. Hars'anyi, Ber. 103, 2330 (1970).

(n) * jTSA8o rfY ^ v ^ -O

J-'pyrldin \ = /

CO ^ PNB CO PNB

10 (III) (IV)

A solution of 1.0 g (0.0015 mol) of (III) and 0.12 ml (0.015 mol of pyridine in 10 ml of methylene chloride under nitrogen atmosphere was cooled to 4 °. The whole acid chloride (II) solution was added at once to the solution (III) and the reaction mixture was stirred at 4 ° for 5 minutes, then at room temperature for 1.5 hours. The organic phase was then washed successively with 70 ml of 0, 1N hydrochloric acid, 80 ml of 1% sodium bicarbonate and 80 ml of water, the methylene chloride phase was dried over magnesium sulfate, the solvent was removed at reduced pressure and the residual oil was chromatographed on Mallinckrodt SilicAR CC-7 silica gel. chloroform was used as the eluant, to give 0.4 g (30.5%) of (IV) as an oil The infrared and nuclear magnetic resonance spectra were consistent for (IV).

c. (IV) _z .-.

toluene v I // v 3Q reflux Οχ "- '/ 0 = 3 ^ [^ \ / 1' o-"

CO PNB

(V) A solution of 0.4 g (0.00045 mol) of IV in 50 ml of toluene is heated under reflux for 4 hours. The solvent was removed at reduced pressure and the residue was chromatographed on Mallinckrodt SilicAR CC-7 silica gel using 5% ethyl acetate in methylene-106

DK 161970 B

chloride as eluant to give 0.15 g (66.6%) of V as an oil which solidified. The infrared and nuclear magnetic resonance spectra were consistent for V.

Analysis for C Hj CHNN6O₂S: Calculated: C: 55.86, H: 3.67, N: 11.33,

Found: C: 56.17, H: 3.76, N: 11.23.

D. (V) s II f /

io h_> VX

A solution of 0.135 g (0.00027 mol) of V in 40 ml of tetrahydrofuran and 40 ml of anhydrous diethyl ether was added to a slurry of 10% palladium-on-charcoal catalyst in 40 ml. ml of water under nitrogen atmosphere.

The resulting mixture was hydrogenated in a Parr hydrogenation apparatus at room temperature at an initial hydrogen pressure of 52 psi for 3.5 hours. Hydrogen uptake was 4.5 psi. The catalyst was removed by filtration, washing the filter pad well with water. Additional diethyl ether was added to the filtrate and the phases separated. The aqueous phase was extracted three times with diethyl ether. The aqueous phase was then concentrated to dryness at reduced pressure. The residue was chromatographed using high pressure liquid chromatography technique to give 0.050 g (58%) of the title penic acid; dec. 156-173 ° C. The infrared and nuclear magnetic resonance spectra were consistent for the desired product.

Analysis for C 15 H 15 N 3 O 3 S, 1.5H 2: 30 Calculated: C: 52.31, H: 5.27, N: 12.20,

Found: C: 51.64, H: 4.95, N: 12.31. 4th

Claims (1)

20 I (IIIa) J-N P (Q) ^ O 3 co2rm 25 wherein Y, Q and R "have the above meanings.