CA1149391A - Process for the preparation of derivatives of clavulanic acid - Google Patents

Abstract

ABSTRACT
The present invention provides a process for the preparation of a compound of the formula (I):
(I) wherein R1 is a hydrogen atom, an alkyl group of up to 5 carbon atoms, a cycloalkyl group of 5 or 6 carbon atoms, a hydroxyalkyl group of up to 5 carbon atoms or a moiety of the sub formula (a):

(a) wherein R2 is a hydrogen, fluorine, chlorine or bromine atom or an alkyl group of 1 - 3 carbon atoms, an alkoxyl group of 1 - 3 carbon atoms, an acyloxyl group of 1 - 3 atoms, a hydroxyl group, an alkoxycarbonyl group containing 1 - 3 carbon atoms in the alkoxy part, or a group -N(R5)CO.R6, -N(R5)SO2R6 or -CO-NR5R6 where R5 is a hydrogen atom or an alkyl group of 1 - 3 carbon atoms or a phenyl or benzyl group and R6 is an alkyl group of 1 - 3 carbon atoms or a phenyl or benzyl group; R3 is a hydrogen, fluorine or chlorine atom or an alkyl group of 1 - 3 carbon atoms, an alkoxyl group of 1 - 3 carbon atoms or an acyloxyl group of 1 - 3 carbon atoms; and R4 is a hydrogen fluorine or chlorine atom or an alkyl group of 1 - 3 carbon atoms or an alkoxyl group of 1 - 3 carbon atoms. The disclosed process comprises inter alia the hydrogenation of a compound of the formula (III):

(III)

Description

~ 3~ ~

Process for the Prep,aration of Derivatives of Clavulanic Acid 1, /0~, ~ I O
C Our earlier Canadian Patent No 1,09~,563 disclosed inter alia a process for the preparation of 5 the compounds of the formula (I):

~ ~ H2-NH CH2 Rl (I) o wherein Rl is a hydrogen atom, an alkyl group of up to S
carbon atoms, a cycloalkyl group of 5 or 6 carbon atGms, a hydroxyalkyl group of up to 5 carbon atoms or a mo~ety of the sub formula (a): R2 R3 (a) ~, 3~

wherein R2 is a hydrogen, fluorine, chlorine or bromine atom or an alkyl group of 1 - 3 carbon atoms, an alkoxyl group of 1 - 3 carbon atoms, an acyloxyl group of 1 - 3 atoms, a hydroxyl group, an alkoxycarbonyl ~roup containing 5 1 - 3 carbon atoms in the alkoxy part, or a group -N(R5)CO.R6, -N(R5)S02R6 or -C0-NR5R6 where R5 is a hydrogen atom or an alkyl gro~pof 1 - 3 carbon atoms or a phenyl or be~zyl group and R6 is an alkyl group of 1'- 3 carbon atoms or a phenyl or benzyl group; R3 is a hydrogen, 10 fluorine or chlorlne atom or an alkyl group of 1 - 3 carbon atoms, an alkoxyl group of 1 - 3 carbon atoms or an acyloxyl group of 1 - 3 carbon atoms; and R4 is a hydro~en fluorine or chlorine atom or an alkyl group of 1 - 3 carbon atoms or an alkoxyl group of 1 - 3 carbon atoms.
15 The disclosed process comprised inter alia the hydrogenation of a compound of the formula (II):

~CH2 -Rl ~ ~ CH2-N (II) or a hydrogenolysable ester thereof wherein Rl is as defined in relation to formula (I) and R7 is a group of the sub-formula (a) as defined in relation to formula (I) It has now been ~iscovered that the compounds of the formula (I) may also be prepared by the catalytic removal of substituted allyl groups from compounds of analogous to those of formula (II) in which the CH2R_ moiety is replaced by a substituted allyl group. This 25 process can improve yields of product and can be more convenient in that quicker reaction times and lower 93~31 pressures of hydrogen may be employed.
The present invention ~rovides a process for the preparation of a compound of the formula (I) as hereinbefore defined which process comprises the catalytic 5 hydrogenation of a compound of the formula (III):

/CH2~R
CH2-N \ (III) CH2cR8~-cR9R
\

or a hydrogenolysable ester thereof wherein R1 is as de~ined in relation to formula (I), or R1 is R1 is a moiety that on hydrogenation provides a group R as defined in formula (I), R8 is a lower alkyl group or a hydr~gen atom, Rg 10is a hydrogen atom or a lower alkyl group and Rlo is a hydrogen atom or a lower alkyl or phenyl group When used herein the term "hydrogenolysable ester" means an ester which on hydrogenation is cleaved to yield the parent carboxylic acid.
When used herein the term "lower alkyl"
means an alkyl group of up to 4 carbon atoms. Thus examples of suitable alkyl groups are the methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl and iso-butyl groups.
Favoured lower alkyl groups include the methyl and ethyl 20groUpS A preferred lower alkyl group is the methyl group.
Suitably Rl is a hydrogen atom. Sui~ably R
is an alkyl group of up to 5 carbon atoms. Suitably Rl is a hydroxyalkyl group of up to 5 carbon atoms. Suitably Rl is a phenyl group optionallysubstituted by a fluorine, 25chlorine or bromine atom or an alkyl or alkoxyl group of up to 3 carbon atoms.
Apt groups Rl include the methyl, ethyl, ~9~391 propyl, butyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, phenyl, p-methoxyphenyl, p-methylphenyl and the like groups. Certain particularly apt groups Rl include the methyl, ethyl.
Other suitable groups Rl include those of the sub-formula (b):

(b) wherein R2 is a hydrogen, fluorlne, chIorine or bromine atom or an alkyl group of l - 3 carbon atoms, an alkoxyl group of l - 3 carbon atoms, an acyloxy group of l - 3 lO carbon atoms, a hydroxyl group or an alkoxycarbonyl group containing l - 3 carbon atoms in the alkoxy part; R3 is a hydrogen, fluorine or chlorine atom or an alkyl group of l - 3 carbon atoms, an alkoxyl group of l - 3 carbon atoms or an acyloxyl group of l - 3 carbon atoms; and 15 R4 is a hydrogen, fluorine or chlorine atom or an alkyl group of l - 3 carbon atoms or an alkoxyl group of l - 3 carbon atoms.
More suitably R2 is a hydrogen, fluorine or chlorine atom or a methoxyl, ethoxyl, hydroxyl, acetoxyl, 20 propionyloxyl, methyl, ethyl, methoxycarbonyl or ethoxy-carbonyl group.
More suitably R3 is a hydrogen, fluorine or chlorine atom or a methoxyl, ethoxyl, acetoxyl, propionoxyl methyl or ethyl group.
More suitably R4 is a hydrogen, fluorine or chlorine atom or a methoxyl, ethoxyl, acetoxyl, propionoxyl, methyl or ethyl group.
More suitably R2 is a hydrogen, fluorine or chlorine atom or a methoxyl, hydroxyl or methyl group.

3~1 Most suitably R3 is a hydrogen, fluorine or chlorine atom or a methoxyl or methyl group.
Most suitably R4 is a hydrogen atom or a methyl or methoxyl group.
Preferably R2 is a hydrogen, fluorine or chlorine atom or a methyl or methoxyl group.
Preferably R3 is a hydrogen atom or methoxyl group.
Preferably R4 is a hy~drogen atom.
Certain particularly favoured values for R
include those of the sub-formula (c):

~ Q
~ (c) wherein Q is a hydrogen, fluorine or chlorine atom or a methyl, methoxyl, ethyl or ethoxyl group.
Suitably Q is a hydrogen, ~-fluorine, 15 m-fluorine, ~-~hlorine or _-chlorine atom or a p-methyl, m-methyl, ~-methoxyl or _-methoxyl group.
Most suitably Q is a hydrogen, ~-fluorine or ~-chlorine atom or a p-methyl or ~-methoxyl group.
Particularly preferably Q is a hydrogen atom.
20 It has been found that the process of this invention is particularly advantageous when employed in the preparation of 9-benzylaminodeoxyclaw lanic acid.
- A further favoured group of values for Rl is that of the sub-formula (d):
OH

Q

~939~

wherein Ql is a hydrogen, fluorine or chlorine atom or a methyl, ethyl, methoxyl, ethoxyl or hydroxyl group.
Suitably the OH substituent shown in formula (VIa) is para- to the carbon to which the -NH-CH2- moiety 5 is attached.
Suitably the OH subsituent shown in formula (VIa) is meta- to the carbon atom to whi-ch the -NH-CH2-moiety is attached.
Most suitably Q is a hyd~ogen-atom or a methyl 10 or methoxyl group.
Yet another favoured group of values for R
is t~at of the sub-formula (e):

N(R5)COR6 (e) wherein R3, R4, R5 and R6 are as defined in relation 'o formula (I).
Suitably R5 is a hydrogen atom or an alkyl group of 1 - 3 carbon atoms such as a methyl group and most suitably R5 is a hydrogen atom, More suitably R6 is an alkyl group of 1 - 3 carbon atoms such as the methyl group.
Favoured values for R3 and P~4 in relation to sub formula (e) are those as defined in relation to sllb-formuia (b). Preferably R3 and R4 are both hydrogen atoms.
Suitably in sub-formula (e) the -N(R5)COR6 moiety is attached para to the -NH-CH2- moiety.
Suitably in sub-formula (e) the -N(R5)COR6 moiety is attached meta tothe -NH-CH2- moiety.

7 _ A particularly favoured group of values for Rl is that of the sub-formula (f):

fi~
~ N(R5)COR6 (f) wherein R5 and R6 are as defined in relation to sub-formula (e). Particularly suitably R5 is a hydrogen atom or an alkyl group of l - 3 carbon atoms such as a methyl group. Preferably R5 is a hydrogen atom. Particularly suitably R5 is an alkyl group of l - 3 carbon atoms and preferably a methyl group.
Particularly apt groups CH2CRg=CRgR1o for use in the compounds of the formula (III) include the following CH2C(CH3)=CH2, CH2C(C2.~5) CH2, 2 3 7 2 CH2C(CH3)=CH.CH3, CH2C(CH3)=C(CH3)2, CH2C(CH3)=CH.C2H5 and CH2.C(CH3)=CH-C6H5-A favoured group CH2 CR8=cR9Rlo is the CH2C(CH3)=CH2 grou~.
A further favoured group CH2CR8=CRgCR10is the CH2C(CH3)=CHPh group.
The compound of the formula (III) may be pre-formed although it is normally produced in-situ by the hydrogenation of a hydrogenolysable ester. It follows that it is a preferred form of the process of this invçntion to employ a hydrogenolysable ester of a compound of the formula (III).
Hydrogenolysable esters for use in this invention are generally benzyl or substituted benzyl esters:
and also optionally substituted allyl esters. Suitable esters include those of the part-formuia (g): C02CHA1A2 wherein Al is a hydrogen atom or a lower alkyl or optionally substituted phenyl group and A2 is an optionally subsituted phenyl group.
Favourably Al is a hydrogen atom.
The nature of the substituent employed in a substituted phenyl group is unimportant as long as it does not interfere with the hydrogenolytic cleavage. Thus suitable substituents include lower alkyl, lower alkoxyl, lower acyloxyl, lower acyl, nitro, cyano, carboxylic -10 acid groups or salts or lower alkyl esters or amides there-of, nitro, halo or similar substituents. Apt substituents include ~ethyl, methoxyl, nitro, chloro, bromo and the like. One, two or three such substituçnts may be employed (except not more than one nitro group should be present).
Favoured esters include the benzyl, nitro-benzyl, bromobenzyl, chlorobenzyl, methylbenzyl and methoxybenzyl esters. Particularly favoured esters include the benzyl, p-nitrobenzyl and p-methoxybenzyl sters. The preferred ester is the benzyl ester.
Further preferred hydrogenolysable ester sroups include those groups CH2CR~=CR9R10 that have been specified hereinbe~ore as being favoured for removal from a nitrogen atom by hydrogenolysis.
The hydrogenation reaction is normally 25 carried out in the presence of a transition metal catalyst.
The catalyst we have preferred to use is palladium, for example in the form of palladium on carbon (charcoal), palladium on barium sulphate, palladium on calcium carbonate, palladium black or the like.
A favoured catalyst is palladium on carbon (sometimes referred to as palladium on charcoal); ~or example 5%, 10%, 20% or 30% palladium on carbon.
The higher palladium content catalyst can be particularly apt-as smaller total weights of catalyst 35 can be employed thereby avoiding possible problems associated with adsorption of product onto the carbon.
... ..
., _ 9 _ Alternatively use of a catalyst containing a lower proportion of metal and a higher quantity of carbon can be used specifically to adsorb the produ~t. Thls aids in isolation as the product may be recovered therefrom there-after by washing.
A low, medium or high pressure of hydrogen may be used in this reaction, for example from l to 6 atmospheres.
However it is one of the considerable advantages of the process of this-invention that it proceeds smoothly and quickly even at atmospheric pressure.
Thus a particularly favoured aspect of this invention comprises carrying out the hydrogenation at atmospheric pressure.
The reaction is normally carried out at a non-extreme temperature, for example from oC to 30C and more usually from 12C to 25C. It is generally convenient to carry out the reaction at ambient temperature.
Suitable solvents for carrying out the hydrogenation include ethanol, n-propanol, isopropanol, tetrahydrofuran, dioxan , ethyl acetate or mixtures of such solvents or such solvents in the presence of water.
favoured solvent is ethanol.
The product may generally be isolated from the reaction mixture by filtering off the solids (the catalyst, which should be well washed to remove the product) and then evaporating the solvent, preferably under low pressure, to yield the initial product. Further purification may be effected by such conventional methods as chromatography over cellulose or other mild stationary phase eluting with a Cl_4 alkanol optionally in the presence of water and optionally in the presence of tetrahydrofuran. Evaporation of the combined active fraction (identified by aqueous potassium permangar.ate spray on tlc) then yields the desired compound in pure form.
.~

,. ... ..... ... ... .... . . .. . . .

9~

_ 10 -The desired product is normally obtained in crystalline form (unless it is an unsalted ester). Trituration under ethanol, isopropanol or the like Cl 4 alkanol or other conventional solvent such as a ketone, ether or ester solvent or other conventional solvent (for example of up to 6 car~on atoms and more suitably of up to 4 carbon atoms) may also be used to aid crystallisation. Recryst-allisation from ethanol or the like may also be employed.
The solvent used in such processes may advantageously be moist.
The compounds of the formula ~III) as herein-before defined and their hydrogenolysable esters ure useful intermediates and as such form part of this invention.
The compounds of the formu~a (III) and their hydrogenolysable esters may be prepared by the methods set forth in Canadian Patent No. l,094,563. In sum~ary an apt form of this process comprises the reaction of an hydrogeno~sabk ester of an acyl derivative of clavulanic acid with an amine of the formula (IV):

~ CH2Rl HN ~ (IV)

2 8 gRl0 wherein Rl, R8, Rg, and Rlo are as defined in relativn to formula (III) and thereafter cleaving the ester if desired.
A favoured acyl deriva~ive is the dichloroac-etate. A favoured ester is the benzyl ester.
The following Examples illustrate the invention.

;..
, .

.. , . . . . . . . . ., . . .. . . , . . . . . . .. .... . .. .. ~, ~93~11 Example 1 Benzyl 9-N-(2l-methylallyl)benzylaminodeoxyclavulana~e Benzyl dichlor~acetylclavulanate (5 g;
12.5 mM) in dimethylformamide (70 cm3) at 0 was treated with N-t2-methylallyl)benzylamine (1.9 equivalents) dropwise with stirring. The mixture was stirred for 3 5 hours at o then poured into athylacetate (250 cm3) and washed with water t5 x 150 cm3) and saturated brine t5 x 100 cm3) dried (anhydrous magnesium sulphate) and evaporated in vacuo to yield an oil. This crude product was chromatographed on silica cluting with cyclohexane/
10 ethylacetate; 1:1. Fractions (detected by aqueous potassium perman~anatespray) were collected containing the title compound Rf (SiO2/ethylacetate:cyclohexane; 1:1) =
0.84. Combined fractions were evaporated to yield an oil 2.8 g (36~).v(film) 1805, 1750, 1695, 1495, 1455, 1303, 15 1230, 1175, 1120, 1015, 895~ 745, 700 cm 1. ~(CDC13) 1.70 (3H, s), 2.85 (2H, s), 2.76 - 3.10 (1H, d), 3.08 (2H, J
7 Hz), 3.40 (1H, dd9 J 17 and 3 Hz) 3.41 (2H, s), 4.71 (1H, t, J 7Hz), 4.75 - 4.95 (2H, broad m), 5.03 (1H, broad s) 5.15 (2H, s) 5.57 (1H, d, J 3 Hz), 7.25 and 7.30 (10 H, 2~ 2 x s).
The intermediate N-(2-methylallyl)benzy amine was prepared as follows:
Benzaldehyde (7.42 g; 70 mM) in 150 cm~ of a solvent mixture of ethylacetate/chloroform/ethanol was 25 treated with 1 equivalent of 2~methylallyl amine ~nd stirred for ~ hour. The mixture was treated with a slight excess of sodium borohydride and stirred for % hour. The 9~91 solvent was removed by evaporation in vacuo and the resi.due was redissolved in ethylacetate (200 cm ) then washed with water (3 x 100 cm3). The free amine was extracted into aqueous hydrochloric acid, the aqueous phase was washed w.th 5 eth~l acetate (2 x 100 cm3). Fresh ethylacetat~ was added (150 cm ) and stirred vigorously with sodium carbonate until alkaline. The ethylacetate phase containing the free amine was washed with water (5 x 100 cm ) and saturated brine (3 x 100 cm3), dried (anhydrous magnesium sulphate) 10 and evaporated to a mobile colourless liquid, yield =
8.1 g (72%) v (film) 3330, 1650, 1495, 1450, 1115, 1030, 895, 735, 700 cm . ~ (CDC13) 1.40 (lH, s, exchanges with D20 ), 1.74 (3H, s) 3.15 (2H, s) 3.70 (2H, s) 4.76 -4.95 (2H, m), 7.25 (5H, m). C11H15N requires 161-1180;
15 161.1192 found.

i39 iL

Example 2 9-N-Benzylaminodeoxyclavulanic acid Benzyl 9-_-(2-methylallyl)benzylamino-deoxyclavulanate (0.5 g) was hydrogenolysed in neat ethanol (30 cm3) in the presence of palladium on carbon (10%; 0.2 g; prehydrogenated for 20 minutes) for 25 5 minutes at atmospheric pressure, The catalyst was filtered o~f and washed with ethanol (10 cm3), the catalyst was then washed with aqueous ethanol (50%;
150cm3), this aqueous ethanolic wash was collected separat-~ely and evaporated to yield a white crystalline solid.
10 This ~olid was washed with cold (0) ethanol and dried to yield 164 mg (49%) of the title compound. Rf (SiO2/butanol-propan--2-ol-water~ 7:7:6) = 0~45 (detection by aqueous potassium permanganate spray). v(Nujol) 1815, 1690, 1612, 1575, 1305, 1187, 1125, 1082, 1065, 1045, 15 1035, 1018, 1005, 990, 950, 892, 750, 695 cm 1 939~

- 14 ~

Example 3 Benzyl 9-N-(4'-acetamidobenzyl)-N-(2-methylallyl) aminodeoxyclavulanate Benzyl dichloroacetyl clavulanate (3.2 g;
8 mm), in dry dimethylformamide (30 cm3) at 0C was treated with 1.9 equivalents of N-(4-acetamidobenzyl)-N-(2'-methylallyl)amine and stirred for 2~ hours at 0C.
5 The mixture was poured into ethyl acetate (250 cm3) and washed with water (4 x 100 cm3) and saturated brine (4 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chroma-tographed on silica gel eluting with ethyl acetate. Fractions were 10 collected containing the title compound, Rf (SiO2/
ethylacetate/cyclohexane 1:1) = 0,33 (detection by aqueous potassium permanganate spray). Combined fractions were evaporated to give a foam, yield = 1.92g (49%), v (film) 3320 (broad), 1805, 1750, 1695, 1670, 1605, 1535, 1515, 15 1455, 1415, 1370, 1310, 1265, 1230, 1175, 1120, 1040, 1020, 895, 830, 750, 700 cm , ~ (CDC13) 1.69 (3H, s), 2.12 ~3H, s), 2.84 (2H, s), 2.75 - 3.07 (lH, m), 3.06 (2H, d, J7Hz), 3.36 (2H, s), 3.40 (1H, dd, J 17 and 3 Hz), 4.69 (1H, t, J 7Hz), 4.74 - 4.98 (2H, broad m), 5.02 (1H, s), 20 5.15 (2H, s), 5.58 (1H, d, J 3Hz), 7.13 - 7.45 (10H, m).

Example 4 9-N-(4'-Acetamidobenzyl)aminodeoxyclavulanic acid Benzyl 9-N-(4'-acetamidobenzyl)-N-(2'-methyl-allyl~ aminodeoxyclavulanate (1.14 g; 2.33 mm) in tetra hydrofuran - ethanol (l:l; 40 cm3) was hydrogenolysed for 4 hours at atmospheric pressure in the presence of 10~
5 palladium on carbon (0.3 g). The catalyst was filtered and washed with aqueous ethanol (30 cm3) and the filtrate evaporated to an oil. This oil was dissolved in tetrahydrofuran-ethanol (50%; lO cm3) and cooled (0) slowly;crystals formed which were filtered off and washed lo with cold (o) tetrahydrofuran-ethanol mixture (l:l) and dried to yield the title compound as white crystals, yield = 172 mg (21~)Rf (SiO2/butanol-propan-2-ol-water;
7;7:6) = 0.45.
~(NUJOL) (1810 - 1790), 1692, 1675, 1600 cm 1. ~ (D20) 15 2.12 (3H, s), 3.04 (1H, d, J 17Hz), 3.53 (1H, dd, J 17Hz and 3 Hz), 3.69 (2H, d, J 7Hz), 4.12 (2H, s), 4.76 (1H, t, J 7Hz), 4.94 (1H, s), 5.69 (1H, d, J 3Hz), 7.40 (4H, s).

3~1 Example 5 Benzyl 9-N-(2'-methyl-3'-phenylallyl)ethylaminodeoxyclavulanate Benzyl dichloroacetylclavulanate (5g; 12,5 mM) in dry dimethylformamide (70 cm3) at -10 was treated with 1.9 equivalents of N-ethyl-N-(2-methyl-3-phenylallyl)amine and stirred for 30 minutes allowing the temperature to rise slowly to ~2 The mixture was poured into iced ethyl-acetate (250 cm3) and washed with water (5 x 100cm3) and saturated brine (5 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was dissolved in toluene (15 cm3) and chromatographed on silica eluting with ethyl acetate - cyclohexane; 1:2. Fractions were collected containing the title compound, Rf (SiO2/ethyl acetate - cyclohexane; 1:1) = 0.5 (detection by aqueous potassium permanganate spray). Combined fractions were evaporated to yield an oil; 1.4g (25%),V (film) 1805, 1750, 1700, 1308, 1175, 1015, 745, 700 cm 1. ~(C~Cl3) 1.C0 (3H, t, J 7 Hz), 1.84 (3H, d, J 1 Hz), 2.42 (2H9 q, J 7 Hz), 2.93 (1H, d, J 17 Hz), 2.96 (2H, s), 3.17 (2H5 d, J 7 Hz), 3.39 (1H, dd, J 17 and 3 Hz), 4.73 (1H, t, J 7 Hz), 5.16 (1H, s), 7~25 and 7.32 (10H, 2 x broad s).

93~31 - 17 _ Example 6 9-N-Ethylaminodeoxyclavulanic acid BenZyl 9-N-(2'-methyl-3'-phenylallyl)ethylaminodeoxy-clavulanate (0.71 g; 1.59 mM) in ethanol (40 cm3) was hydrogenolysed at atmospheric pressure in the presence of palladium on carbon (10%), 250 mg (which had been prehydrogenated for 15 minutes) for 1 hour. The catalys-t was filtered off and washed with aqueous ethanol (50 cm3), the filtrate was evaporated and ethanol was added, the resulting crystalline solid was filtered off cold (0) and washed with a little cold ethanol. Drying afforded the title compound as a white crystalline solid, yield = 78 mg. The filtrate was again evaporated, cold methanol was added and the resulting crystalline solid filtered off, washed with cold methanol and dried to yield a further 10 mg of the title compound;
total yield = 88 mg (24%). Rf (SiO2/butanol -isopropanol -water; 7:7:6) = 0.38 (detection by aqueous potassium permanganate spray). ~(Nujol) (3700-2000) very broad, 1808, 1695, 1620, 1585, 1302, 1190, 1120, 1045, 1020, 1008, 925, 895, 870, 802, 750 cm 1. ~ (KBr) (3700-3140), (3140-2890), (2890-2600), (2540-2100), 1790, 1690 (1675-1510), 1470, 1390, 1375, 1300, 1185, 1118, 1042, 1018, 920, 895, 803, 752 cm 1.
~ (D20) 1.21 (3H, t, J 7 Hz), 3.02 (2H, q, J 7 Hz), 3.07 (1H, d, J 17 Hz), 3.56 (1H, dd, J 17 and 3 Hz), 3.6~ (2H, d, J 7.5 Hz), 4.77 (1H, broad, t, J 7.5 Hz), 4.96 (1H, s), 5.74 (1H, d, J 3 Hz).

Example 7 Benzyl 9-N-(2"-methylallyl~_N_(1' 2'.~'.6'-tetrahvdrobenzYl) aminodeoxyclavulante Benzyl dichloroacetylclavulanate (6g; 15mM) in dry dimethylformamide (40 cm3) at 0 was treated with N-(2"-methylallyl)-N-(1',2',3',6'-tetrahydrobenzyl) amine (1.9 equivalents) and stirred at 0 for 1~ hours. The mixture was poured into ethyl acetate (200 cm3) and washed with water (5 x 100 cm3) and saturated brine (5 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated to yield an oil. This oil was chromatographed on silica gel eluting with ethyl acetate - cyclohexane; 1:1.
Fractions were collected containing the title compound, Rf (SiO2/ethylacetate - cyclohexane; 1:1) = 0.9 (detection by aqueous potassiurn permanganate spray). Cornbined fractions were evaporated to an oil, yield = 3.2 g (48%).
~(film) 1805, 1750, 1695, 1450, 1305, 1175, 1120, 1042, 1010, 895, 745, 700, 655 cm~~c ~ (CDC13) 1.00 - 2.30 (7H, broad m), 1.67 (3H, s), 2.14 (2H, d, J 6 Hz), 2.80 (2H, s), 2.96 (1H, d, J 17 Hz), 3.10 (2H, d, J 7 Hz), 3.42 (1H, dd, J 17 and 3 Hz), 4.68 (1H, t, J 7 Hz), 4.7-4.9 (2H, broad m), 5.04 (1H, s), 5.16 (2H, s), 5.58-5.70 (3H, broad m), 7.32 (5H, s).

Example 8 9-N-Hexahydrobenzylaminodeoxyclavulanic acid Benzyl 9-N-(2~-methylallyl)-N-(1l,2t,3l,6 t -tetra-hydrobenzyl)aminodeoxyclavulanate (1.26 g; 2,9 mM) in ethanol (50 cm3) was hydrogenolysed at atmospheric pressure for 40 minutes in the presence of palladium on carbon (10%) (400 mg) which had been prehydrogenated for 1~ hour. The catalyst was filtered off and washed with ethanol (20 cm3) then with 50% aqueous ethanol (100cm3). This aqueous washing was evaporated to yield a white crystalline solid. This solid was slurried in cold ethanol and filtered off, washed with a few cm3 of cold (0) ethanol and dried to yield 0.41 g (48%) of the title compound. Rf (SiO2/butanol-propan-2-ol-water; 7:7:6) = o.6 (detection by aqueous potassium permanga nate spray). V(Nujol) 1805, 1692, 1610 (broad), 1590 (broad), cm 1. 'H nuclear magnetic resonance showed that the cyclohexenyl C = C was only partially reduced. The mixed zwitterionic products were dissolved in 50% aqueous ethanol (40 cm3) and hydrogenated in the presence of 110 mg palladium on carbon (10%) for 3 hours at atmospheric pressure, filtered and the catalyst washed with aqueous ethanol (20 cm3), the filtrate was evaporated to yield a white crystalline solid, ethanol was added (20 cm3) and cooled (0). The solid was filtered off and washed with cold ethanol, dried to yield 0.3 g (30%) of the title compound. ~ (Nujol) 1805, 1695, 1610 (broad), 1305, 1190, 1120, 1080, 1070, 1050, 1020, 1008, 950, 900, 850, 810, 760 cm 1. ~ (D20) o.6-2.0 (11H, broad m), 2.83 (2H, d, J 6 Hz), 3.07 (1H, d, J 17 Hz), 3.55 ~1H, dd, J 17 and 3 Hz), 3.67 (2H, d, J 7 Hz), 4.75 (1H, t7 J 7 Hz),

4.95 (1H, s), 5.73 (1H, d, J 3 Hz)~

~t93~

Example 9 BenzYl 9-N-(2'-methylallyl)-N-(n-propyl)aminodeoxyclavulanate To a solution of benzyl dichloroacetylclavulanate (8.0g, 20 mmol) in dimethylformamide (100 ml) at -10C was added N-(2'methylallyl)-N-(n-propyl)amine (4.3 g, 38 mmol) in dimethylformamide (15 ml). After 30 mins at -10C the reaction mixture was poured into ethyl acetate and ex-tracted with water (4 x). The organic phase was washed with brine, dried (MgS0~) and evaporated to a yellow oil which was chromatographed on silica gel. The title ester was obtained on elution with petrol/ethyl acetate : 1/1 grading to 1/2.
Yield, as an oil, 4,2 g (55%).
I.R. (CDCl3) 2950, 1800, 1745, 1695 and 900 cm 1 N.M.R. (CDCl3) 0.81 (3H, t, J 7 Hz) 9 1.41 (2H, sextet, J 7 Hz), 1.68 (3H, s), 2.23 (2H, t, J 7 Hz), 2.81 (2H, s), 2.96 (1H, d, J 17 Hz), 3.10 (2H, d, J 7 Hz), 3.44 (1H, dd, J 17 and 3 Hz), 4.69 (1H, bt, J 7 Hz), 4.80 (2H, bs), 5.05 (1H, s), 5.16 (2H, s,) 5.63 (1H, d, J 3 Hz), and 7.34 (5H, s).

~939~

Example 10 9-N-(n-Propyl)aminodeoxyclavulanic acid -A mixture of tetrahydrofuran (150 ml~ and water (15 ml) containing 10% Pd on carbon (1.6 g) was hydrogenated at atmospheric pressure for 20 mins. Benzyl 9-N-(2l-methylallyl)-N-(n-propyl)aminodeoxydeoxyclavulanate (3.9g, 10.2 mmol) in tetrahydrofuran (15 ml) was added and the hydrogenation was continued for 40 mins. The catalyst was filtered off (celite) and the filter cake was washed which crystallised on trituration with iso-propanol. Yield = 0.190g.
The filter-pad from above was now washed with 50%
aqueous ethanol. Evaporation and trituration with iso_ propanol afforded the title compound as a white solid (0 91 g). Total yield of title compound = 1.1 g (45~).
I R. (KBr) 3540-3370, 2960, 1795, 1780, 1700 and 1615 cm 1 N.M.R. (D2Q) 0.90 (3H, t, J 7 Hz), 1.64 (2H, sextet, J
7 Hz), 2.94 (2H, t, J 7 Hz), 3.09 (1H, d, J Hz), 3.56 (1H, dd, J 17 and 3 Hz), 3.69 (2H, d, J 7 Hz), 4.78 (1H, bt, J 7 Hz), 4.97 (1H, s), and 5.75 (1H, d, J 3 Hz).

Example 11 Benzyl 9-N-(n-butyl)-N-(2'-methyl-3'-phenylallyl)amino-deoxyclavulanate Benzyl 9-0-dichloroacetylclavulanate (9733 g; 23.3 mmol) in dry dimethylformamide (90 ml) was stirred and cooled to -10C. N-(n-Butyl)-N-(2~-methyl-3~-phenylallyl)amine (9 g; 44.3 mmol) in dry dimethylformamide (90 ml) was then added dropwise. The solution was then stirred at -10C
for 30 minutes.
The solution was then poured into an ethyl acetate/water mixture and shaken. The two layers were then separated and the aqueous phase was extracted with more ethyl acetate.
The combined organic phases were then washed with water, brine, dried (MgS04), filtered and evaporated under a reduced pressure to give a dark yellow oil. Column chromatography through silica-gel eluting with ethylacetate petroleum ether 1:2 gave the title compound as a light yellow oil in a 35% yield.
V max (CHC13): 1800, 1750, 1720 and 1640 cm 1 ~(CDCl3): 0.70-~1.05 (3H, m) 1.06 >1.68 (4H, m), 1.85 (3H, s), 2.19 ~ 2.51 (2H, m), 2.90 (1H, d, J 17 Hz), 2.97 (2H, s), 3.19 (2H, d, J 7 Hz), 3.39 (1H, dd, J 17 and 3 Hz), 4.75 (1H, t, J 7 Hz), 5.09 (lH, s), 5.17 (2H, s), 5~62 (1H, d, J 3 Hz), 6.38 (1H~ br, s), and 7.02-~7.54 (10H, m).

i93~i Example 12 9-N-(n-Butyl)-aminodeoxyclavulanic acid Benzyl 9-N-(n-butyl)-N-(2-methyl-3-phenylallyl)amino-deoxyclavulanate (3.80 g, 8 mmole) in tetrahydrofuran (T.H.F.) (40 ml) was added to a prehydrogenated mixture of 10% palladium on charcoal (2 g) in 10% aqueous T.H.F.

5 The mixture was then hydrogenated at atmospheric pressure for 1 hour.
The catalyst was then filtered through a celite pad and the 'cake' washed with 10% aqueous T.H.F. and then with 50% aqueous ethanol. The filtrate was then evaporated -to 10 dryness under a reduced pressure and T,H,F~ added. The white crystalline solid was then filtered off and from the spectral data obtained found to be the title compound in 30% yield.
~ max (KBr): 1800, 1784, 1695, and 1610 cm 1 15 ~ (D20): 1.01 (3H, m), 1.57 (4H, m), 3.12 (2H, t, J Hz), 3.25 (1H, d, J 17 Hz), 3.75 (1H, dd, J 17 and 3 Hz), 3.83 (2H, d, J 7 Hz),4.93 (1H, broad, t, J 7 Hz), 5.14 (1H, s), and 5.88 (1H, d, J 3 Hz).

~9391 _ 24 -Example 13 Benzyl 9-N-(2'-methylallyl)-N-(3"-methylallyl)aminodeoxy-clavulanate Benzyl dichloroacetylclavulanate (7.4 g; 18.5mM) in dry dimethylformamide (50 cm3) at 0 was treated with N-(2'-methylallyl)-N-(3"-methylallyl) amine (1.9 equivalents) and stirred at 0 for 45 minutes. The mixture was poured into ethyl acetate (200 cm3) and washed wit~
water (6 x 100 cm3) and saturated brine (6 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chromatographed on silica eluting with ethyl acetate - cyclohexane (1:2), fractions were collected Rf (SiO2/ethyl acetate - cyclohexane; 1:2) = 0.5 (de~ection by aqueous potassium permanganate spray). Combined fractions were evaporated to yield the title compound an oil, yield = 2.7 g (37%). ~ (~ilm) 1805, 1750, 1700, 1450, 1380, 1305, 1230, 1175, 1120, 1080, 1042, 1015, 970, 895, 740, 700 cm 1. ~ (CDCl3) 1.58-1.80 (6H,m ), 2.81 (4H, broads), 2.95 (1H, d, J 17 Hz), 3.08 (2H, d, J 7 Hz), 3.42 (1H~ dd, J 17 and 3 Hz), 4.68 (1H, t, J 7 Hz), 4.79 (2H, broad s), 5.03 (1H, s), 5.15 (2H, s), 5.36-5.56 (2H, broad m), 5,60 (1H, d, J 3 Hz), 7.32 (5H, s).

3~1 ~5 _ Example 14 9-N-n-Butylaminodeoxyclavulanic Acid -Benzyl 9-N-(2'-methylallyl)-N-(3"-methylallyl) amino-deoxyclavulanate (1.37 g); in ethanol (30 cm3) was hydrogenolysed at atmospheric pressure in the presence of palladium on carbon, 10% (0.5 g, prehydrogenated for 20 minutes) for 25 minutes. The catalyst was filtered off and washed with aqueous ethanol (50 cm3). The filtrate was evaporated, ethanol added and cooled (0). A white crystalline solid was filtered off and dried (354 mg).
Thin layer chromatography on silica showed that this solid was a mixture of 9-N-n-butylaminodeoxyclavulanic acid and 9-N-isobutylaminodeoxyclavulanic acid and 9-N-isobutyl-aminodeoxyclavulanic acid, the former being present as the major constituent, and less polar Rf (SiO2-butanol-propan-2-ol-water: 7:7:6) = 0.53 than the iso derivative Rf = 0.50.
The mixture was chromatographed on cellulose eluting with butanol-propan-2-ol- water; 8:8:1. Fractions were collected containing the title compound Rf = 0.53. Combined fractions were evaporated to a white crystalline solid, 25 mg. ~ (Nujol) (2800-2100), 1805, 1690, 1600 (broad), 1300, 1182, 11l0, 1080 1067, 1045, 1015, 1005, 940, 910, 892, 865, 805, 755 cm 1.
~ (D20) 0.65 - 1.05 (3H, m) 1.05 - 1.82 (4H, m), 2~96 (2H, t, J 7 Hz), 3.07 (1H, d, J 17 Hz), 3.57 (1H, dd, J 17 and 3 Hz), 3.68 (2H, d, J 7 Hz), 4.76 (1H, t, J 7Hz), 4.95 (1H, s), 5.73 (1H, d, J 3 Hz).

3~1 Example 15 Benzyl 9-N-(3',4',5'-trimethoxyhenzyl)-N-(2"-methylallyl) aminodeoxyclavulanate _ Benzyldichloroacetylclavulana-te (5.49 g; 13.7 mM) in dry dimethylformamide (50 cm3) at 0C was treated with N-(3,4,5-trimethoxybenzyl) 2'-methylallylamine (1.9 equivalents) dropwise with stirring. The mixture was stirred at 0 for 2 hours then poured into ethylacetate (250 cm3) and washed with water (5 x 150 cm3) and saturated brine (5 x 150 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chromatographed on silica eluting with ethylacetate-cyclohexane; 1:2. Fractions were collected containing material Rf 0.78 (SiO2/ethylacetate-cyclohexane;
1:1). Combined fractions were evaporated to yield the title compound as an oil; yield = 2.4 g (34%). ~ (film) 1805, 1750, 1695, 1590, 1502, 1455, 1420, 1330, 1308, 1185, 1175, 1125, 1010, 895, 745, 700 cm 1. ~ (CDC13) 1.73 ~3H, s), 2.85 (2H, s), 2.96 (1H, d, J 17 Hz), 3.13 (2H, dS J
7 Hz), 3.37 (2H, s), 3.45 (1H, dd, J 17 and 3 Hz), 3.82 (9H, s), 4.73 (1H, t, J 7 Hz), 4.86 (2H, broad s), 5.07 ~1H, s3, 5.18 (2H, s), 5.61 (1H, d, J 3 Hz), 6.54 (2H~ s), 7.31 (5H, s).

Example 16 9-N-(3',4',5'-Trimethoxybenzyl)aminodeoxyclavulanic acid Benzyl 9-N-(3',4',5'-trimethoxybenzyl)-N-(2"-methyl-allyl)aminodeoxyclavulanate (2.0 g; 3.83 mM) in ethanol (50 cm ) was hydrogenolysed at atmospheric pressure in the presence of palladium on carbon (10%), 0.6 g (prehydrogenated for 15 minutes) for 20 minutes, water (10 cm3) was added and hydrogenolysis continued for 10 minutes. The catalyst was filtered off and washed with aqueous ethanol (30 cm3) and the clear filtrate evaporated.
Ethanol (30 cm3) was added to yield a white crystalline solid. The solid was filtered off cold (0) and washed with a little cold ethanol. Drying gave the title compound as a finely crystalline solid, yield = 0.61 g (42%), Rf (SiO2/butanol-propan-2-ol-water; 7:7:6) = 0.55.
U (Nujol) 1805, 1695, 1615, 1595, 1300, 1250, 1192, 1165, 1130, 1045, 1008, 920, 895, 830, 782, 750 cm~1, ~ (KBr) 1790, 1695, (1620-1590), 1510, 1464, 1427, 1385, 1334, 1300, 1247, 1190, 1160, 1123, 1040, 1020, 1005, 957, 920, 895, 850, 830, 783, 745 cm 1. ~(D20) 2.99 (1H, d, J
17 Hz), 3.50 (1H, dd, J 17 and 3 Hz), 3.64 (2H, d, J 7 Hz), 3.72 (3H, s,), 3.80 (6H, s), 4.05 (2H, s), 4.74 (1H, t, J 7 Hz), 4.92 (1H, s), 5.64 (1H, d, J 3 Hz), 6.72 (2H,s).

_ 28 --Example 17 Benzyl 9~N~N-bis(2~-methYlallyl)aminodeoxyclavulanate~
Benzyl dichloroacetylclavulanate (5 g; 12.5 mm) in dry dimethylformamide (75 cm3) at 0 was treated with bis (2-methylallyl)amine (1,9 equivalents) and stirred at 0 for 2 hours. The mixture was poured into ethylacetate (250 cm3) and washed with water (5 x 100 cm3) and saturated brine (5 x 100cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chromatographed on silica eluting with ethylacetatecyclohexane (1:1).
Fractions were collected containing the title compound Rf (SiO2/ethylacetate-cyclohexane; 1:1) = 0.82 (det~ction by aqueous potassium permanganate spray). Combined fraction~
were evaporated to yield an oil, 1.46 g (29%).
~ (film) 1805, 1750, 1695, 895, 755, 700 cm 1. ~
(CDCl3) 1.67 (6H, s), 2.78 (4H, s~, 2.95 (1H, d, J 17Hz), 3 03 (2H, d, J 7Hz), 3.42 (1H, dd, J 17 and 3Hz), 4.67 (1H, t, J 7Hz), 4.80 (4H, broads), 5.03 (1H, s), 5.17 (2H, s), 5.61 (1H, d, J 3Hz), 7.33 (5H, s).

t39~

Example 18 9-N-Isobutylaminodeoxyclavulanic acid Benzyl 9-N,N-bis(2'-methylallyl)aminodeoxyclavulanate (0.8 g; 2.02 mm) in ethanol (30 cm3) was hydrogenated in the presence of palladium on charcoal 10% (0.3 g) for 10 min at atmospheric pressure; the catalyst had been pre-hydro-genated for 20 minutes. The catalyst was filtered off and washed with aqueous ethanol (50 cm3), the filtrate was evaporated in vacuo and ethanol ~dded, after cooling at 0 a crystalline solid was filtered off and washed with cold ethanol, drying in vacuo afforded the title com~ound as a white crystalline solid; yield = 190 mg (37%) Rf (SiO2/butanol-propan-2-ol-water; 7:7:6) = 0.45 ~ (Nujol) 1805, 1690, 1610, 1570, 1185, 1110, 1080, 1070, 1045, 1020, 1005, 930, 895, 885, 857, 810, 758 cm 1. ~ (B r) 3570 (broad), 3350 (broad), 3220 (broad), 2840-2740, 2450 (broad), 1780, 1695, 1600 (very broad), 1470, 1392, 1320, 1295, 1110, 1045, 1020, 1003, 987, 932, 893, 885, 812, 750 cm 1. ~ (D20) 0.94 (6H, d, J, 6Hz), 1.90 (1H, m), 2.82 (2H, d, J 6Hz), 3.07 (1H, d, J 17Hz), 3.57 (1H, dd, J 17 and 3 Hz), 3.70 (2H, d, J 17 and 3 Hz), 3.70 (2H, d, J
7Hz), 4.77 ~1H, t, J 7Hz), 4.96 (1H, d), 5.73 (1H, ~, J 3Hz).

3~1 Example 19 Benzyl 9-N-isobutYl-N-(2'-meth~1-3'-phenylallyl)amino-deoxYclavulanate Benzyl dichloroacetylclavulanate (7.16 g; 17.9 mM) in dry dimethylformamide (85 cm3) at -12 was treated with 1.9 equivalents of N-isobutyl-N-(2-methyl-3-phenylallyl) amine and stirred at -15 for 15 minutes then for 45 minutes between -10 and 0. The mixture was poured into iced ethylacetate (250 cm3) and .washed with water (5 x 100 cm3), saturated brine (5 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated in the presence of toluene to a small volume. This crude product was chromatographed on silica eluting with ethylacetate - cyclohexane; 1:2.
Fractions were collected containing the title compound Rf (SiO2/ethylacetate - cyclohexane; 1:2) = 0.89. Combined fractions were evaporated to afford the title compound as as oil, yield = 1.60 g (19%),~ (film) 1808, 1750, 1690, 745 700 cm 1 ~ (CDCl3) 1.85 (6H, d, J 6 Hz), 1.50 2.20 (6H, broad m), 2.92 (1H, d, J 17 Hz), 2.94 (2H, s), 3.39 (1H, dd, J 17 and 3 Hz), 4.73 (1H, broad, t, J 7 Hz), 5.07 (1H, broad s), 5.17 (2H, s), 5.60 (1H, d, J 3 Hz)~ 6.35 (1H, broad s), 7.25 and 7.32 (10 H, 2 x s).

3~11 Example 20 9-N-Isobutylaminodeoxyclavulanic acid ., . ~ . .
Benzyl 9-N-(2'-methyl-3'-phenylallyl)-N-isobutyl~nino-deoxyclavulanate (1,44 g; 3.04 mM) in ethanol (25 cm3) was hydrogenolysed in the presence of palladium on carbon (10% Pd), 0.5 g (which had been prehydrogenated for 15 minutes), for 45 minutes at atmospheric pressure. The catalyst was filtered off and washed with ethanol (50 cm3), then with aqueous ethanol (100 cm3), the aqueous washing was collected separately and was evaporated to yield the title compound as a white crystalline solid. The solid was washed with a little cold ethanol, drying afforded 248 mg of the title compound. The ethanolic catalyst washing and the solvent from the hydrogenolysis were evaporated, ethanol added (10 cm3) and cooled, crystals were filtered off and dried to yield a further 17 mg of the title compound, total yield = 265 mg (34%). The infrared and proton magnetic resonance spectra were identical to the product obtained by hydrogenolysis of benzyl 9-N-N-bis(2'-methylallyl)aminodeoxyclavulanate.

Example 21 Benzyl 9-N-(2'-methylallyl)-N-(3"-methylallyl)aminodeoxy-clavulanate Benzyl dichloroacetylclavulanate (7.4 g; 18.5 mM) in dry dimethylformamide (50 cm3) at 0 was treated with N-(2'-methylallyl)-N-(3"-methylallyl) amine (1.9 equivalents) and stirred at 0 for 45 minutes. The mixture was poured into ethyl acetate (200 cm3) and washed with water (6 x 100 cm3) and saturated brine (6 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chromatographed on silica eluting with ethyl acetate - cyclohexane (1:2)5 fractions were collected Rf (SiO2/ethyl acetate - cyclo-hexane; 1:2) = 0.5 (detection by aqueous potassium permanganate spray). Combined fractions were evaporated to yield the title compound as an oil, yield = 2.7 g (37%). ~ (film) 1805, 1750, 1700, 1450, 1380 1305, 1230, 1175, 1120, 1080, 1042, 1015, 970,895, 740, 700 cm 1.
S (CDCl3) 1.58-1.80 (6H, m), 2.81 (4H, broads), 2.95 (1H, d, J 17 Hz), 3.08 (2H, d, J 7 Hz), 3.42 (1H, dd, J 17 and 3 Hz), 4.68 (1H, t, J 7 Hz), 4.79 (2H, broad s), 5.03 (1H, s), 5.15 (2H, s), 5.36-5.56 (2H, broad m), 5.60 (1H, d, J 3 Hz), 7.32 (5H, s).

9~

Example 22 9-N-Isobutylaminodeoxyclavulanic acid Benzyl 9-N-(2-methylallyl)-N-(3'-methylallyl)amino-deoxyclavulanate (13~g) in ethanol (30 cm3) was hydrogenolysed at atmospheric pressure in the presence of 10% palladium on charcoal (0.5 g which had been prehydrogenated for 20 minutes) for 25 minutes. The catalyst was filtered off and washed with aqueous ethanol, the filtrate was evapo~ated and ethanol added. The resulting crystals were filtered off cold and dried. This product was chromatographed on cellulose eluting with butanol-isopropanol-water; 4:4:1.
Fractions were collected containing the tit]e compound in low yield Rf(siO2/butanol-isopropanol water; 7:7:6)=
o.46 (detection by aqueous potassium permanganate spray).

Example 23 Benzyl 9-N-(2'-methylallyl)-N-(3"-transphenylallyl) aminodeoxyclavulanate Benzyl dichloroacetylclavulanate (5.9g; 14.8 m~i) in dimethylformamide (40 cm3) at 0 was treated with N-(2'methylallyl)-N-(3'-transphenylallyl) amine (1.9 equivalents) and stirred at 0 for 13/4 hours. The mix-ture was then poured into ethyl acetate (250 cm3) and washed with water (5 x 100 cm3) and saturated brine (5 x 100 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chromatographed on silica eluting with ethylacetate-cyclohexane (1:2), fractions were collected containing the title compound; Rf(SiO2/ethylacetate:cyclo-hexane 1:1) = 0.76 and combined fractions were evaporated to yield an oil, 3.49 g (51%). Detection by aqueous potassium permanganate spray. v (film) 1805, 1750, 1700, 1495, 1450, 1305, 1230, 1175, 1120, 1080, 1045, 1015, 967, 895, 745, 695 cm 1. ~ (CDCl3) 1~71 (3H, s), 2.89 (2H, s), 2.93 (1H, d, J 17Hz), 3.07 (2H, d, J 6Hz), 3.16 (2H, d, J
7Hz), 3.39 (1H, dd, 1 17 and 3Hz), 4.72 (1H, t, J 7Hz), 4.75-4.95 (2H, broad m), 5.06 (1H, d, J 3Hz), 5.15 (2H, s),

6.15 (1H, dt, J 16 and 6Hz), 6.45 (1H, d, J 16Hz), 7.15-

7.50 (10H, m).

~9~391 Example 24 9-N-Isobutylaminodeoxyclavulanic acid Benzyl 9-N-(2'-methylallyl)-N-(3"-trans phenylallyl) aminodeoxyclavulanate (11g) in ethanol (40 cm3) was hydrogenolysed for 20 minutes at atmospheric pressure in the presence of 10% palladium on charcoal (300 mg;
which had been prehydrogenated for 10 minutes). The catalyst was filtered off and washed with aqueous ethanol.
The filtrate was evaporated and e;thanol added, the resulting crystals were fil-tered off cold and dried. This product was chromatographed oncellulose eluting with butanol-isopropanol water; 4:4:1. Fractions were collected containingthe title compound in low yield Rf(SiO2/butanol-lsopropanol-water; 7:7:6) = o.46 (detection by aqueous potassium permanganate spray)~

~9~1 ~xample 2$
Benzyl 9-N-(2~-methylallyl)-N-(2"-methyl-3~'-phenYlallyl) aminodeoxYclavulanate Benzyl 9-0-dichloroacetylclavulanate (6.30 g; 15.8 mmole) in acetonitrile (60 ml) at 4C was treated with dropwise addition of N-(2'-methylallyl)-N-(2"-methyl-3l'-phenylally) amine (6 g; 30 mmol) in acetonitrile (60 ml).
On final addition the reaction was stirred at 4 to 10C
for 2 hours.
The acetonitrile was then removed under a reduced pressure and the resulting oil was dissolved in ethyl acetate. The solution was then washed with water, brine, dried (MgS04) and evaporated in vacuo. Silica-gel column chromatography afforded the title compound as as an oil in a 16% yield.
V max (CHCl3): 1802, 1745, 1695 and 1600 (br~ cm 1.
~ (CDCl3): 1.70 (3H, s), 1.82 (3H, s), 2.84 (2H, s), 2.92 (2H, s), 2.90(1H, d, J 17 Hz), 3.12 (2H, d, J 7 Hz), 3.38 (1H, dd, J 17 and 3 Hz), 4.70 (1H, br.t, J 7 Hz), 4.82 (2H, br.s), 5006 (1H, s), 5.16 (2H, s), 5.60 (1H, d, J 3 Hz), 6.36 (1H, s), 7.22 and 7.30 (10H, 2 x s).

Example 26 9-N-Isobutylaminodeoxyclavulanic acid Benzyl-9-N-(2'-methylallyl)~N-(2"-methyl-3"phenylallyl) aminodeoxyclavulanate (1.0 g; 2 mmol) in ethanol (20 ml) was carefully added to a pre-hydrogenated mixture of 10% palladium on charcoal (300 mg) in ethanol (30 ml).
The mixture was then hydrogenated at atmospheric pressure for 30 minutes. The catalyst was then filtered of.~ and washed well with aqueous ethanol; The filtrate plus washings were then evaporated to dryness under a reduced pressure. Cellulose column chromat.ography af~orded the ti~le compound as a white crystalline solid in 30% yield.

~93~9~ -Example 27 Benzyl 9-N-(iso-butyl)-N-(2'-methylallyl)aminodeoxyc]avulanate .
N-Isobutyl-N-(2-methylallyl)amine (7.25 g, 57 mmol) in dimethylformamide (30 ml) was added dropwise to a solution of benzyl dichloroacetylclavulanate (12.0 g, 30 mmol) in dimethylformamide (200 ml) at -10C. After 2 hours at this temperature the reaction mixture was poured into water and extracted with ethylacetate. The organic phase was washed several times with brine, dried (~gS04) and evaporated to a yellow oil. Chromatography in sllica gel (elution : petrol/ethylacetate : 3/1 grading to 2/1) afforded the title ester as an oil, 2.98 g (25%) I.R. (CHCl3) 1802, 1745, 1700, and 895 cm 1 N.M.R. (CDCl3) 0.84 (6H, d, J 7 Hz), 1.52-1.~8 (1H, m) 1.68 (3H, s), 2.00 (2H, d, J 7 Hz), 2.79 (2H, s), 2.94 (1H, d, J 17 Hz), 3.06 (2H, d, J 8 Hz), 3.41 (1H, dd, J
17 and 3 Hz), 4.68 (1H, bt, J 8 Hz), 4.78 (2H, bs), 5.03 (1H, bs), 5.17 (2H, s), 5.61 (1H, d, J 3 Hz), and 7.32 (5H, s).

Example 28 9-N-Isobutylaminodeoxyclavulanic acid _ 10% Pd-C ~0.83 g) in ethanol (80 ml) was hydrogenated for 15 minutes at 1 atmospheric of hydrogen, Benzyl 9-N-(isobutyl)-N-(2'-methylallyl)aminodeoxyclavulanate (2.5 g, 6.28 mmol) in ethanol (30 ml) was added and the hydrogenation continued for 45 minutes. The catalyst was then filtered off through celite and the pad was washed with some ethanol. These combin~d washings were evaporated to a yellow oil which crystallised from ethanol (0.12~ g).
The filter pad, above was now washed with 50%
aqueous ethanol (150 ml). Evaporation afforded the til;le material as a white solid (0.'70 g).
Combination of all the mother liquors and evaporation afforded a dark oil which was chromatographed on silica gel (elution : ethylacetate/isopropanol/water : 5/2/1 grading to 5/4/3) to provide more of the title product (0.115 g).
Total yield of required product = 0.935 g (59% yield).
N.M.R., I.R , and t.l.c. characteristics were identical to an authentic sample.

~am~2~
Phenacyl 9-N-Bis (2'-methylall~l)aminodeoxyclavulanate Phenacyl 9-0-dichloroacetylclavulanate (5.0 g; 11.7 mmol) in dry dimethylformamide (50 ml). The mixture was cooled to 0C and bis (2'-methylallyl) amine (2.8 g;
2Z.2 mmol) in dry dimethylformamide (30 ml) was added dropwise. After stirring at 0C for 1~ hours the mixture was poured into ethyl acetate and washed several times with water and then dried (MgS04). After filtration the ethyl acetate was removed in vacuo to give a yellow oil, which on column chromatography afforded the required compound as a yellow gum, yield 32%.
[~]20+ 11.0 (c. 1%, CHCl3). Found C, 67.60; H, 6.70; N
6.38%, C24H28H205 requires: C, 67.91; H, 6.65; N, 6 60%
max (CHCl3) 1805, 1760, and 1605 cm ; S (CDCl3) 1.72 (6H, s), 2.76-~ 3.22 (7H, m), 3.45 (1H, dd, J 17 and 3 Hz), 4-82 (5H, m), 5.19 (1H, s), 5.38 (2H, s), 5.66 (1H, d, J
3 Hz), 7.30-~7.60 and 7.78-t8.00.

~9 3 Example 30 Allyl 9-N,N-bis(2'-methylallyl)aminodeoxyclavulanate Allyl dichloroacetylclavulanate (5 g; 14.3 mM) in dry dimethylformamide (50 cm3) at 0 was treated with bis (2 ~ethylallyl)amine (1.9 equivalents) and stirred 2~ hours at between 0 and 5C. The mixt~lre was poured into ethylace-tate (250 cm3) and washed with water (5 x 200 cm3) and saturated brine (5 x 150 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil. This oil was chromatographed on silica eluting with ethylacetate - cyclohexane; 1:1. Fractions were collected containing the title compound, Rf (SiO2/ethylacetate -cyclohexane; 1:1) = 0.90 (detection by aqueous potassium permanganate spray). Combined fractions were evaporated in vacuo to yield an oil, 1.33 g (27%), (film) 1808, 1750, 1695, 1450, 1370, 1308, 1232, 1180, 1120, 1015, 940, 895 cm 1.
(CDCl3) 1.71 (6H, s), 2.83 (4H, s), 2.98 (1H, d, J 17 Hz), 3.07 (2H, d, J 7 Hz), 3.45 (1H, dd, J 17 and 3 Hz), 4.55-4.94 (7H, m), 5.02 (1H, s), 5.17 - 5.5 (2H, m), 5.63 (1H, d, J
3 Hz), 5.6 - 6.16 (1H, m).

3;~

Example 31 (2-Methylallyl) 9'-N-(IsobutYl)-N-(2"-Methylallvl) amino-deoxyclavulanate (2-Methylallyl)-9~-0-dichloroacetylclavulanate (9.05 g;
24.8 mmol) in anhydrous dimethylformamide (90 ml) was cooled with stirring to 20C. N-(Isobutyl)-N-(2-methyl-allyl) amine (6.0 g; 47 mmol) in anhydrous dimethylformamide (60 ml) was added dropwise over a period of 20 minutes.
The reaction mixture was allowed to warm to -10C and stirring continued for 2 hours.
The solution was poured into a cold mixture of ethyl acetate and water and shaken. The aqueous layer was extracted with more ethyl acetate. The combined or~anic layers were washed with water, dried (MgS04) and evaporated to an oil. Column chromatography afforded the title com-pound as a colourless oil in 23% yield.
~ max (CHCl3): 1805, 1750 and 1700 cm 1. ~(CDC13):
0.85 (6H, d, J 7Hz), 1.70 (3H, s), 1.77 (3H, s), 1.57 to 1.88 (1H, m), 2.05 (2H, d, J 7Hz), 2.84 (2H, s), 2.94 (1H, d, J 17Hz), 3.11 (2H, d, J 7Hz), 3.46 (1H, dd, J
17 and 3Hz), 4.58 (2H, s), 4.74 (1H, broad t, J 7Hz), 4.81 (2H, broad s), 4.99 (2H, broad s), 5.06 (1H, s), and 5.66 (1H, d, J 3Hz).

l9~1 Exam~le ~2 9-N-Isobutylaminodeoxyclavulanate (2-Methylallyl)-9'-N-(isobutyl)-N-(2"-methylallyl) aminodeoxyclavulanate (1.5g; 4 mmol) in ethanol (20ml) was carefully added to a pre-hydrogenated mixture of 10%
palladium on charcoal (0.5g) in ethanol (20 ml). The mixture was hydrogenated at 1 atmosphere until the uptake of hydrogen ceased.
The mixture was filtered through a celite pad and the "cake" washed with aqueous ethanol. The filtrate plus washings were evaporated to dryness resulting in a yellow solid which an addition of a small amount of ethanol gave a white solid. Filtration afforded the title compound in 20% yield. Spectral data was consistent with an authentic example.

Example 33 Benzyl 9-N-methyl-N-(2'-methylallyl)aminodeoxyclavulanate A solution of benzyl dichloroacetylclavulanate (6g; 0.015 mol) in dimethylformamide (80 ml) was cooled to -20 and a solution of N-methyl-N-(2-methylallyl)amine (2.4g; 0.028 mol) in dimethylformamide (10ml) was added slowly dropwise over 10 mins~ The reaction mixture was stirred at -10 for 2 hours then poured into ethyl acetate, washed with water, brine, dried and evaporated. Two crude product was chromatographed on silica eluting with etnyl acetate-cyclohexane, 3:1. Combined fractions were evaporated to afford the title compound as an oil, yield =
9%.
max (CHCl3) 1795, 1730, 1690 (sh), 1630 cm 1 S(CDC13) 1.71 (3H, s), 2.09 (3H, s) 2.81 (2H, s), 2.g8 (1H, d), 3.04 (2H, d, J 8Hz), 3.45 (1H, d, J 3Hz), 4.72 (1H, bt, J 8Hz), 4.82 (2H, bs), 5.07 (1H, bs), 5.18 (2H, s), 5.63 (1H, d, J 3Hz), 7.3 (5H, s).

Example 34 9-N-Methylaminodeoxyclavulanic acid A solution of benzyl 9-N-methyl-N-(2'-methylallyl) aminodeoxyclavulanate (200 mg) in ethanol : tetrahydrofuran :
water (7:2:1, 30ml) was hydrogenolysed at atmospheric pressure in the presence of 10% palladium on carbon (70mg) for 2 hours. The catalyst was filtered off and the pad washed well with aqueous ethanol. The filtrate and washings were combined and evaporated to give a solid which cryslallised from acetone to afford the title cDmpound in L~o% yield. This product was identical (t.l.c., i.r., n.m.r) to an authentic sample of 9-N-methylaminodeoxyclavulanic acid.

~93~1 Example 35 Benzyl 9-N-methyl-N-(2'-methyl-3'-phenyallyl)aminodeoxy-clavulanate A cold (-10) solution of benzyl dichloroacetylclavulanate (6.5g; 0.016 mol) in dimethylformamide (75ml) was treated dropwise with a solution of N-methyl-N-(2-methyl-3-phenyl-allyl) amine in dimethylformamide (25 ml) and stirred for 4 hours at -10. The mixture was poured into ethyl ace-tate (150 ml) and extracted with aqueous tartaric acid (3.0g in 100ml water: 0.02 mol), the acidic extract was basified to pH 8.3 and re-extracted with ethyl acetate. The ethyl acetate solution was washed with brine, dried (di-sodium hydrogen orthophosphate) and evaporated. Toluene was added during evaporation until only a small amount of sol-vent was present, this was loaded onto a silica gel column and the product eluted with ethyl acetate. The product was isolated as an oil in 7% yield.
~ max (film), 1805, 1750, 1700 cm 1 ~ (CDCl3) 1.85 (3H, d, J 1.5Hz), 2.13 (3H, s), 2.93 (1H, d, J 17Hz), 2~92 (2H, s), 3.09 (2H, d, J 8Hz), 3.39 (1H, dd, J 17 and 3Hz), 4.74 (1H, dt, J 8 and 1.5Hz), 5.07 (1H, bs), 5.16 (2H, s), 5.61 (1H, d, J 3Hz), 6.36 (1H, bs), 7.25, 7031 (10H, 2xs). Found M+ 432.2069, C26H28N2~4 requires 432.2049.

~9~1 Example 36 9-_-methylaminodeoxyclavulanic acid Benzyl 9-N-methyl-N-(2'-methyl-3'-phenylallyl)aminodeoxy-clavulanate (500mg) in ethanol (50ml) was hydrogenolysed at ambient pressure in the presence of 10% Pd-C (160mg) for 3 hours. The catalyst was fil-tered off and washed with aqueous ethanol; the filtrate and washings were combined and evaporated. The crude product was fractionated on silica gel using ethyl acetate : isopropanol : water, 5:4:4, as eluent.
The secondary amine was eluted and isolated as a crystalline solid in 20% yield.
max (KBr) 3420, 3000, 2760, 2430, 1779, 1693, 1618 cm 1.
~ (D20) 2.65 (3H, s), 3.15 (1H, d, J 17Hz), 3.62 (1H, dd, J 17 and 3Hz), 3.74 (2H, d, J 8Hz), 4.85 (1H, bt, J 8Hz), 5.05 (1H, bs), 5082 (1H, d, J 3Hz).

Description 1 Allyl 9-0-dichloroacetylclavulanate Allylclavulanate (6.3 g; 26 mm) in dichloromethane (100 cm3) at -30C was treated with pyridine (3 cm3) and dichloroacetylchloride (1 equivalent) and stirred ~or 10 minutes at -20C. The mixture was diluted with dichloromethane (100 cm3) and washed with aqueous citric acid solution (10%; 50 cm3), water (3 x 100 cm~), saturated brine (3 x 150 cm3), dried (anhydrous magnesium sulphate) and evaporated to an oil yield = 8.3 g (9OD/o~, Rf (SiO2/ethylacetate - cyclohexane 1:1) = 0.78.

Description 2 Phenacyl-9-Dichloroacetyl Clavulanate Phenacyl clavulanate (14.26 g; 45 mmol) in dry methylene chloride (100 ml) was treated with pyridine (4 mls, 50.6 mmol) at room temperature. The reaction mixture was cooled to -30C and dichloroacetyl chloride (4.3 mls, 1,2 equivalents) in dry methylene chloride (15 ml) was added dropwise. After stirring at -30C for 30 minutes the mixture was allowed to warm to 0C and was then poured into dilute hydrochloric acid. The organic phase was separated and washed with more dilute hydrochloric acid, sodium bicarbonate solution, water, brine and then dried (MgS04). After filtration the methylene chloride was removed in vacuo to afford a yellow oil which crystallised on trituration with ether. Yield = 11.21 g, 50%. A sample recrystallised from ether gave the following physical characteristics:
m.p. 75-77C []2~ + 16.1, (c. 1%; CHC13).

Description 3 (2-Methylallyl)clavulanate Sodium clavulanate (25g; 83 mmol) in anhydrous dimeth~lformamide (100 ml) was treated at room temperature over a period of 15 minutes with methallychloride (15.1g;
166 mmol) in dimethylformamide (50 ml) plus a catalytic amount of sodium iodide. The mixture was then stirrea at room temperature overnight.
The mixture was then poured into an ethyl acetate/
water mixture and shaken. The two layers were separated and the aqueous layer extracted with ethyl acetate. The organic layers were combined, washed with water, washed with a saturated solution of sodium chloride, dried (MgS04) and evaporated to give the title compound as an oil in 73%
yield.
V ax (CHC13) : 1810, 1750, 1695 and 1~60 cm 1.
(CDC13) : 1.75 (4H, s), 3.05 (1H, d, J 17Hz), 3 50 (1H, dd, J 17 and 3Hz), 4.23 (2H, d, J 7Hz), 4.58 (2H, s), 4.93 (1H, t, J 7Hz), 5.00 (2H, broad s), 5.09 (1H, m), and 5.70 (1H, d, J 3 Hz).

Descri~ion 4 (2-Methylallyl)-9'-0-Dichcloroacetvlclavulanate (2-Me-thylallyl)clavulanate (15.3g; 60 mmole) in anhydrous dichloromethane (150ml) was treated at room temperature with anhydrous pyridine (4.8ml; 60 mmol) and was added dropwise over a period of 10 minutes. T1le 5 reaction mixture was stirred at -40C for 1 hour and then allowed to warm to 0C.
The mixture was poured into cold dilute hydrochloric acid and separated. The organic layer was then washed several times with more dilute hydrochloric acid, water 10 and a saturated solution of sodium chloride, dried (MgS04) and evaporated to an oil affording the title compo~nd in 87% yield.
~ maX(CHCl3): 1810, 1755 and 1700 cm 1.
(CDCl3): 1.76 (3H, s), 3.10 (1H, d, J 17Hz), 3.5~ (1H, dd, J 17 and 3Hz), 4~60 (2H, s), 4.78 to 5.00 (5H~ m), 5.13 (1H, s), 5.77 (1H, d, J 3Hz), and 5.93 (1H, s).

Claims (15)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for the preparation of a compound of the formula (I):

(I) wherein R1 is a hydrogen atom, an alkyl group of up to 5 carbon atoms, a cycloalkyl group of 5 or 6 carbon atoms, a hydroxyalkyl group of up to 5 carbon atoms or a moiety of sub formula (a):

(a) wherein R2 is a hydrogen, fluorine, chlorine or bromine atom or an alkyl group of 1 - 3 carbon atoms, an alkoxyl group of 1 - 3 carbon atoms, an acyloxyl group of 1 - 3 atoms, a hydroxyl group, an alkoxycarbonyl group containing 1 - 3 carbon atoms in the alkoxy part, or a group -N(R5)CO.R6, -N(R5)SO2R6 or -CO-NR5R6 where R5 is a hydrogen atom or an alkyl group of 1 - 3 carbon atoms or a phenyl or benzyl group and R6 is an alkyl group of 1 - 3 carbon atoms or a phenyl or benzyl group; R3 is a hydrogen, fluorine or chlorine atom or an alkyl group of 1 - 3 carbon atoms, an alkoxyl group of 1- 3 carbon atoms or an acyloxyl group of 1-3 carbon atoms;
and R4 is a hydrogen fluorine or chlorine atom or an alkyl group of 1 - 3 carbon atoms or an alkoxyl group which process comprises the catalytic hydrogenation of a compound of the formula (III):

(III) or a hydrogenolysable ester thereof wherein R1 is as defined in relation to formula (I), or R1 is R1 where R11 is a moiety that on hydrogenation provides a group R1 as defined in relation to formula (I), R8 is hydrogen atom or a lower alkyl group, R9 is a hydrogen atom or a lower alkyl group and R10 is a hydrogen atom or a lower alkyl or phenyl group.

2. A process as claimed in claim 1 for the preparation of a com-pound of the formula (I) wherein R1 is a phenyl group.

3. A process as claimed in claim 1 for the preparation of a com-pound of the formula (I) wherein R1 is a p-acetamidophenyl group.

4. A process as claimed in claim 1 for the preparation of a com-pound of the formula (I) wherein CH2R1 is an isobutyl group which process comprises the hydrogenation of a compound of the formula (III) wherein CH2R1 is an isobutenyl group.

5. A process as claimed in claim 1 for the preparation of a com-pound of the formula (I) wherein CH2R1 is an isobutyl group.

6. A process as claimed in claim 1 wherein the moiety CH2CR8=
CR9R10 is CH2C(CH3)=CH2, CH2C(C2H5)=CH2, CH2C(nC3H7)=CH2, CH2C(CH3)=CHCH3, CH2C(CH3)=C(CH3)2, CH2C(CH3)=CHC2H5 or CH2C(CH3)=
CH.C6H5.

7. A process according to claim 1 where CH2CR8 = CR9R10 is CH2C(CH3)=CH2 or CH2C(CH3) = CHC6H5.

8. A process as claimed in claim 1 wherein the esterifying radical is benzyl, p-bromobenzyl, p-chlorobenzyl, p-methylbenzyl or p-methoxybenzyl.

9. A process as claimed in claim 1 wherein the esterifying radical is 2-methylallyl, 2-ethylallyl, 2-n-propylallyl, 2-methyl-3-methylallyl, 2-methyl-3,3-dimethylallyl, 2-methyl-3-ethylallyl or 2-methyl-3-phenylallyl.

10. A process as claimed in claim 1 wherein the hydrogenation reaction is performed in the presence of a palladium metal catalyst.

11. A process as claimed in claim 10 wherein the palladium catalyst is palladium on charcoal, palladium on barium sulphate, palladium on calcium carbonate or palladium black.

12. A process as claimed in claim 11 wherein the catalyst is palladium on carbon with a proportion of palladium between 1% and 30%.

13. A process as claimed in claim 1 wherein the pressure of hydro-gen used is between 1 and 6 atmospheres.

14. A process as claimed in claim 1 wherein the reaction tempera-ture is maintained between 0° and 30°C.

15. A process as claimed in claim 1 wherein the solvent for the hydrogenation reaction is ethanol, n-propanol, isopropanol, tetra-hydrofuran, dioxan or ethyl acetate, or a mixture of these solvents in the presence of water.