FI78071B - MELLANPRODUKT ANVAENDBAR VID FRAMSTAELLNING AV TIENAMYCIN. - Google Patents

Description

1 78071

The present invention relates to an intermediate for the preparation of thienamycin starting from L-aspartic acid of formula a) - I 1 ii J-NR1 10 0

wherein R 1 is a protecting group such as tert-butyldimethylsilyl, or OH

b) I SR

J-NR1 SR

wherein R is a protecting group such as tert-butyldimethylsilyl, and R is a lower alkyl group, or

OH

20 C) Π I 7 vi J-NH 1 -CO 0 R 1 7 0 '2] R is a protecting group such as p-nitrobenzyl, or

OH

25 d '^ Y-r ^ V

7 VII

-Nhn ^ -co2r wherein R is a protecting group such as p-nitrobenzyl.

The compounds of the invention are used in the preparation of thienamycin, i.e. 3-aminoethylthio-6- (1-hydroxyethyl) -1-azabicyclo 3.2.0 -hept-2-en-7-one-2-carboxylic acid and its pharmaceutically acceptable esters of the acid of formula 2 78071

OH

> —R Vsx 2! il 1

5 £ N-, Λ- C OOH

O

Thienamycin has been described e.g. in Finnish patents 53,718 and 66,001, and in J.Am. Chem. Soc. 100 (1978): 1, 313-314.

The present invention therefore relates to the overall synthesis starting from L-aspartic acid, and the synthesis is carried out stereoselectively via intermediates II, III and IV: rC1 J-NR1

O

20 OH

/ \ __ 111 I f

λ - N --’- COOR

0'X

25

OH

^: - f ^ VX IV

30 N --— COOR

wherein X is a conventional leaving group such as an arylsulfonyloxy group, and R * is a common easily removable protecting group such as a triorganosilyl group. Details of the total synthesis of 3,78071 5 are shown in the following reaction scheme:

C02H

2 nh2 -> 10

CO ^ R

R0oc \ 1 2 NH2 -> 15 2

^ CO, R

20 -2 _ ^

/, - NH

O

3 25 n ^ 0H -,

J-NH

o 4

/ V

30 4 78071 - ^ oso2ch3 / N ->

O H

5, 4a

/ V

r-r · _>

J-NH

10 0 5 Λ '—rr 15 ,, _ y II * / 7 o 6 SR2 -y ^ Y ^ SR3 20 111 έκ4 _ * J-NR 7

O

7 OH SR2 A_ / A5 * 3 25 | λ iR4 -

-NR V

<f 8

Oh 30 ^ I - '(^^ CO, R5 O ~ * 9 / N ^ 5 78071 OR2 / · - ^ COjR5 s Π * 1 "* 0 10 OR2

/ _ / VCHO

10, _HR1 11 r- OR2 Λη ^, ·· - J-NR1 0 12 20 OR2 / •• ι — 1 ^ \ 0Η, lco9m -> „_NR1 θ '13 25 / - OR2 λγ ~ (Ύ",

J, _NR1 UU2K

30 ° ^ OR2

Ar- / V0 7 JIL · - 0 35 A $ 6 78071

OH

5 J, NH CO 2 R 2

0 16 VI

/ - '

OH

io s ^ ·· i- ^ y0 N2 CO202 - *

O

17 VI1 / V / 15

OH

A- y-v> 0 7 ->

} -N-. ..C0, R

1 '1 20 "

OH

/ '· ______ ^ N_ X

4- il_L_ CO-R7 25 0

19 OH

NHR8 I | 7>

30 0 - N - 1 - CO2R

20

OH

A. nh2

35, _ N_I .__ COOH

o '7 78071

As stated, L-aspartic acid 1 is esterified in a known manner. Typically, 1 is reacted in a solvent such as benzene, toluene, chloroform or the like with an esterifying agent such as benzyl alcohol, methanol, ethanol, isopropanol and the like in the presence of p-toluenesulfonic acid, HCl, HBr and the like at 0-110 ° C. for 1-24 hours to obtain the desired product and thus to protect the carboxyl functions. The obtained compound 2 is treated in a solvent such as ether, THF, DME or the like with trimethylchlorine-10 and the like and then with EtMgBr, MeMgJ, 0MgBr, t-BuMgCl and the like -40 to + 50 ° At C for 1-72 hours to give azetidinone ^ 3. Reduction of compound 3 with a reducing agent such as NaBH 4 or the like in a solvent such as methanol, ethanol, isopropanol and the like at -10 to + 40 ° C for 1 to 6 hours gives compound ^ (symbols used herein Et ,

Me, O, iPr and t-Bu mean ethyl, methyl, phenyl, isopropyl and tert-butyl, respectively).

Treatment of compound 4 in a solvent such as methylene chloride, CHCl 3 and the like, methanesulfonyl chloride, methanesulfonic anhydride or the like in the presence of a base such as Et 2 N, N 2 O 4 or the like and then a stoichiometric amount of acetone or even a 5-fold amount of sodium is obtained. via, compound ^ 5.

In the reaction, a protecting group R is added, which may be, for example, a triorganosilyl group such as a t-butyldimethylsilyl, t-butyldiphenylsilyl, triphenylsilyl, isopropylmethylsilyl group, or, for example, a 3,4-dimethoxybenzyl group. Silyl protection is more preferred, and R 1 is attached, for example, by treating J 5 in a solvent such as dimethylformamide, acetonitrile, hexamethylphosphoramide, tetrahydrofuran and the like, a silylating agent such as t-butyldimethylchlorosilane, t-butyldiphenyldiphenyldiphenyldiphenyl -20 to + 25 ° C for 0.5 to 20 hours, in the presence of a base such as triethylamine, diisopropylethylamine or imidazole.

8 78071

Reaction 6 -> 7 is carried out by treating compound 6j in a solvent such as tetrahydrofuran, dimethoxyethane, diethyl ether or the like with a carbanion, which can be generally represented by the following formula: 5 * SR2 M®C® - SR3 \ SR4 10 where M is a metal cation , such as lithium, potassium, copper 2 3 4 or magnesium, and R, R and R represent alkyl, aryl or aralkyl, such as methyl, ethyl, benzyl, methoxybenzyl, trityl or phenyl, at -100 -0 ° C 0.5 -4 hours. The carbanion reagent is typically prepared prior to addition to the reaction with the compound by treating the triorganothiomethane with a strong base such as n-butyllithium, t-butyllithium, phenyllithium, lithium diisopropylamide (LDA) and the like.

The alkylation is performed by treating the compound 20 in a solvent such as tetrahydrofuran, dimethoxyethane, diethyl ether, hexamethylphosphoramide at -100-20 ° C with a strong base such as lithium diisopropylamide, lithium hexamethyldisilazide, lithium 2,2 , 6-tetramethylpiperide, potassium 25 hydride and the like, and then adding acetaldehyde from an equivalent amount to a 10-fold excess. This reaction gives a mixture of isomers from which the desired trans-R form can be conveniently separated by chromatography or crystallization.

Reaction 8 to 9 can be carried out by treating rv in a solvent such as methanol, ethanol, isopropanol, water and the like at 0 to 80 ° C with a Lewis acid such as mercuric chloride, silver tetrafluoroborate, thallium trinitrate and the like. The meaning of R is determined. according to the alcohol used in the reaction.

78071 9

In reaction 9 - (U), the hydroxyl protecting group R2 is attached. Most preferred protecting groups R 2 are triorganosilyl groups such as t-butyldimethylsilyl, t-butyldiphenylsilyl, triphenylsilyl and the like. at 0 / 5-25 hours.

The reduction H) -> VI, is carried out by treating the compound in a solvent such as toluene, methylene chloride, diethyl ether, tetrahydrofuran and the like with a reducing agent such as diisobutylaluminum hydride, sodium bis (2-methoxyethoxy) aluminum hydride. At C for 1-10 hours.

15 The addition reaction 11 to »12 is carried out by

r ~~> / "U

compound u in a solvent such as tetrahydrofuran, diethyl ether, dimethoxyethane, etc., at -100 to 0 ° C for 6 to 15 minutes with LiCl 2 CO 2 R, wherein R is benzyl, p-methoxybenzyl, 2.4 -dimethoxybenzyl or the like, this reagent is typically prepared in situ by treating R 6 acetate with a strong base such as LDA, lithium hexamethyldisilazide, lithium 2,2,6,6-tetramethylpiperide and the like.

If desired, the first attached R 1 can be replaced with a removable carboxyl protecting group R for the bomb. This reaction 12 13 14 is carried out by removing the selective

IV Λ / V

protecting the compound 12 by hydrogenation or hydrolysis to give compound 12. The reaction is typically carried out by hydrogenating compound 12 in a solvent such as methanol, ethanol, dioxane, tetrahydrofuran, water or the like at a pressure of 1-4 atm hydrogen under a catalyst such as Pd / carbon, PdiOH or the like, in the presence of 0.1 to 10 hours. Intermediate 1 ^ (M may be e.g. H, Na, K or ammonium such as Et 2 NH) need not be isolated. Intermediate 14 is obtained from the hydrogenation mixture by treating it with a reagent capable of coupling R7, such as 1078071 with an aralkyl halide in a solvent such as dimethylformamide, acetonitrile, hexamethylphosphoramide, at 0-50 ° C for 0.5-18 hours. is typically an aralkyl group such as p-nitrobenzyl or o-nitro-5-benzyl.

Oxidation 1 ^ 4 -> i5 is carried out by treating λΑ in a solvent such as methylene chloride, acetonitrile and the like with an oxidation system such as dipyridine-chromium (VI) oxide, 3,5-dimethylpyrazole-10 chromium (VI) oxide, pyridinium chlorodiacrate, pyridinium chlorochromate, with dimethyl sulfoxide, acetic anhydride-dimethyl sulfoxide and the like, at -78 to + 25 ° C for 5 minutes to 8 hours.

Removal of the protecting groups R and R (1 £ -> 1 £) is carried out by acid hydrolysis in an aqueous medium using a solvent such as methanol, ethanol, tetrahydrofuran, dioxane, and an acid such as hydrochloric acid, sulfuric acid, acetic acid and the like, 0-100 ° C: within 2-18 hours 20.

The diazo compound 17 is prepared from the compound 16 by treating it in a solvent such as CH 2 Cl 2, THF and the like with an azide such as p-carboxybenzenesulfonyl azide, toluenesulfonyl azide, methanesulfonyl azide, a base such as triethylamine, 2H), (C 2) pyridine, or the like, in the presence of 1-50 hours at 0-25 ° C.

Cyclization 17 to 18 is carried out by treating compound 17 in a solvent such as benzene, toluene, Λχ * 30 in THF and the like at 50 to 110 ° C for 1 to 5 hours with a catalyst such as bis (acetylacetonato) CU (II ) in the presence of CuSO 4, Cu powder, Rh (OAc) 2 or Pd (OAc) 2. Alternatively, the cyclization can be performed by irradiating compound 1 through 7 a pyrex filter 35 (wavelength greater than 300 nm) in a solvent such as benzene, CCl 2, diethyl ether, etc. at 0-25 ° C for 0.5-2 hours / OAc = asetaatti7.

n 78071

Coupling of the leaving group X (18 -> 19) is performed with an acylated ketoester 18 with an acylating agent

O

RA / such as p-toluenesulfonic anhydride, p-nitrophenylsulfonic anhydride, 2,4,6-triisopropyl-5-phenylsulfonic anhydride, methanesulfonic anhydride with toluene sulfone, toluenesulfonic acid chloride, p-bromo-phenyl; p-nitrophenylsulfonyloxy, methanesulfonyloxy, p-bromophenyl-10-sulfonyloxy or any other conventionally used leaving group well known in the art. Typically, the above acylation to attach the group X is performed in a solvent such as methylene chloride, acetonitrile, or dimethylformamide in the presence of a base such as diisopropyl-ethylamine, triethylamine, 4-dimethylaminopyride, and the like at -20 to + 40 ° C from 0.5 to 5 ° C. within an hour. The leaving group X of intermediate 1J may also be halogen. The halogen group is attached by treating the compound 1 with a halogenating agent such as: 11a, O 6, 6 (O) 3 PBr or oxalyl chloride in a solvent such as

In C 1 -C 4, CH 2 Cl 2, THF, etc., in the presence of a base such as diisopropylethylamine, triethylamine or 4-dimethylethylaminopyridine.

Reaction 19 is carried out by treating compound 19 in a solvent such as dioxane, dimethylformamide, dimethyl sulfoxide, acetonitrile, hexamethylphosphoramide, etc., with mercaptan reagent 8 8 (equivalent or excess) HSCH 2 Cl 2 NHR, where R is readily deprotected or hydrogen , such as p-nitrobenzyloxycarbonyl, o-nitrobenzyloxycarbonyl and the like, in the presence of a base such as sodium hydrogencarbonate, potassium carbonate, triethylamine, diisopropylethylamine and the like at -40 to + 25 ° C for 1 to 72 hours. The mercaptan reagent HSCl For 4 hours.

The final deprotection is carried out in a conventional manner, such as by hydrolysis or hydrogenation. Typically, the compound 2E is hydrogenated in a solvent such as dioxane-water-ethanol mixture, tetrahydrofuran-10 dipotassium hydrogen phosphate aqueous solution-isopropanol mixture and the like under a hydrogen pressure of 1-4 atm in the presence of a hydrogenation catalyst such as Pd / carbon, palladium hydroxide, etc. at 0.5-50 ° C. -4 hours to give compounds I.

In the aldol reaction described above, wherein the hydroxyethyl side chain is attached, a mixture of isomers (trans-R, trans-S and cis-R) is obtained directly from which the desired trans-R isomer can be separated by chromatography or crystallization. The aldol reaction can be carried out via intermediates to stereoselectively obtain the trans-R isomer, as follows: 13 78071 SR2 _ / N ^ SR3 __Li ^ r4

CT

5 7 r- '

Direct acetylin- (B) \ (A) 0H 2 “\ Α_ ^ Υ« 3, 0 ^ O * SR4 o ψ oxidation 0 SR2 15 μl ^ / y ^ '\ - j / ^ n ^ sr3 ^ NR1 ^ Ö 20 (D) Reductions M /? H SR2 /··.—/y sri

J-NR

o 8 r ~> 30 in which formulas all symbols have the same meaning as above.

78071 14

In the above reaction scheme, step A has been described previously. Direct acetylation, step B, is performed by treating the compound with two or more equivalents of a base such as lithium diisopropylamide, lithium hexamethyldisilazide, lithium 2,2,6,6-tetramethylpiperide, in a solvent such as tetrahydrofuran, diethyl ether or dimethoxy. At 100 to 20 ° C with an acylating agent such as N-acetylimidazole or the like. Most preferably, a mixture of the compound and the base 10 is added to the acylating agent.

Oxidation step C is performed with an oxidant such as dipyridine chromium (VI) oxide, trifluoroacetic anhydride-dimethylsulfoxide-triethylamine, pyridium dichromate, acetic anhydride-dimethyl-15 sulfoxide in a solvent such as methylene chloride, methylene chloride, - Within 5 hours.

Reduction step D is performed by contacting the ketone with a reducing agent such as potassium tri (mixed-butyl) borohydride, lithium tri (sec-butyl) borohydride, sodium borohydride, sodium tris (methoxyethoxy) aluminum hydride, lithium aluminum hydride, dichloromethane, e.g. in tetrahydrofuran, toluene and the like, at -20 to + 25 ° C. The reaction is preferably carried out by adding a complexing salt such as potassium iodide, magnesium bromide and the like.

From the verbal description of the reaction scheme for the overall synthesis of thienamycin above, it is to be understood that there is considerable choice in the reaction parameters.

30 This choice has generally been demonstrated by listing equivalent solvent systems, temperature ranges, and various reagents suitable for use. Furthermore, it is to be understood that the presentation of the synthesis scheme in clear steps in a particular order has been performed for ease of description rather than as a necessity; namely, it should be noted that the mechanically separated 78071 reactions represent a uniform synthetic scheme, and that certain steps can be combined, run simultaneously, or performed in reverse order without changing the course of the synthesis.

The following examples illustrate the invention.

Example 1

Preparation of 4 (S) -4-iodomethylazetidin-2-one Step A

10, r 2 CO 2 CH 2 ^ __ ^ C ° 2CH 2 O 0CH 2 O 2N NH 2 * TSOH -OCH 2 O 2 NH 2 ^ aco-CH-0 15 1 '2 2 -> ^ CH 2 O 2 NHSiKe 3 -> -

- NH

20 0 *

Benzyl (S) -azetidin-2-one-4-carboxylate To a 1000 mL separatory funnel is added dibenzyl (S) -aspartate p-toluenesulfonic acid salt (48.6 g, 0.1 mol), ice-cold diethyl ether (300 mL). ), ice-cold water (100 ml) and ice-cold saturated aqueous potassium carbonate solution (50 ml). The mixture is shaken vigorously and the layers are separated. The aqueous phase is further extracted with cold diethyl ether (2 x 100 ml). The combined ether solutions were washed with brine, dried over magnesium sulfate and evaporated in vacuo to give dibenzyl (S) -aspartate (31.4 g, 0.1 mol) as a colorless liquid.

78071 16

A solution of dibenzyl (S) -aspartate in anhydrous diethyl ether (200 ml) is cooled in an ice bath under nitrogen. Trimethylchlorosilane (12.7 mL, 0.1 mol) is added to the solution with stirring to give a white precipitate. Triethylamine (14.0 mL, 0.1 mol) is then added to the mixture. The cooling bath is removed and the mixture is stirred at room temperature (22-25 ° C) for 2 hours. The mixture is filtered directly into a 1-liter round-bottomed 3-necked flask equipped with a glass sinter-10 filter, a magnetic stirrer, and a tube for vacuum and nitrogen flow. The filtration is carried out in a nitrogen shielding gas and care is taken to ensure that the humidity of the air is not affected. The glass sinter filter is replaced with a stopper and the ether is evaporated in vacuo with stirring to give dibenzyl (S) -N-trimethylsilyl aspartate (35.5 g, 0.092 mol) as a slightly cloudy oil.

Anhydrous diethyl ether (250 mL) is added to the flask containing the silyl derivative and the magnetic stirrer is replaced with a mechanical stirrer. The resulting solution is stirred under a nitrogen atmosphere and cooled in an ice bath. An ethereal solution of ethylmagnesium bromide (34 ml of a 2.94 M solution, 0.1 mol) is added dropwise over 40 minutes to give a cream-colored miscible precipitate. The cooling bath is removed and the mixture is stirred at room temperature. After 1.5 hours, a viscous rubber forms. The mixture is allowed to stand overnight at room temperature, then cooled in an ice-methanol bath, and 2-N hydrochloric acid saturated with ammonium chloride (100 ml) is slowly added thereto with stirring. The resulting mixture was diluted with ethyl acetate (100 mL) and water (100 mL), and the layers were separated. The aqueous phase is further extracted with ethyl acetate (3 x 100 ml). The combined organic solutions are washed with water (200 mL), 5% aqueous sodium carbonate (100 mL), water (100 mL) and brine, dried over magnesium sulfate and filtered.

17

Evaporation of the solvent in vacuo gave an orange oil with a fine granular precipitate (25.3 g). This material is dissolved in warm chloroform (75 ml), the solution is diluted with petroleum ether (125 ml), seed crystals are added, the edges of the vessel are scraped and the solution is cooled in an ice bath. The precipitate was collected, washed with petroleum ether and dried in vacuo to give benzyl (S) -azetidin-2-one-4-carboxylate o (3.85 g) as an off-white solid, m.p. 136-139 C.

10 The mother liquors and washings are combined, diluted to 500 ml with light petroleum, seeded with seed crystals and left in the refrigerator for several days. The resulting precipitate was collected, washed with petroleum ether and dried in vacuo to give more of the desired product (0.82 g) as pale yellow crystals. Recrystallization of the sample from chloroform-petroleum ether gives small white flakes. Sp. 141-143 ° C; ft (? D = 4343.4 ° (c = 3.275, CHCl 3); IR (CHCl 3): 3425, 1778, 1746 cm -1; 1 H NMR (CDCl 3): c T 3.00 (ddd, 1, J = 1 , 9, 3.2 and 14.6 Hz, H-3a), 20 cf 3.35 (ddd, 1, J = 1.5, 5.4 and 14.6 Hz, H-3b), 6 * 4 .20 (dd, 1, J = 3.2 and 5.4 Hz, H-4), δ 5.22 (s, 2, OCH 2 Ph), # 6.48 (m, 1, NH), 7.38 (s, 5, phenyl): mass spectrum m / e 205 (M +), 163, 91, 70, 43.

Analysis calculated for C C 64.38, H 5.40, N 6.83

Found: C 64.10, H 5.70, N 6.77.

ie 78071

Step B

co2ch20 - | ^ XOH

I -> \ - N

/ Lks H

To a suspension of 4 (S) -4-hydroxymethylazetidin-2-one 4 (S) -azetidin-2-one 4-carboxylate (20.0 g, 10 97.5 mmol) in 300 mL of anhydrous methanol is added 0 ° C: sodium borohydride (3.69 g, 97.5 mmol) in one portion. The mixture is then allowed to warm slowly, cooling from time to time to maintain an internal temperature of 30 ° C. The mixture is stirred for 2 hours, glacial acetic acid (23.5 g, 390 mmol) is added and the reaction mixture is evaporated in vacuo. The residue is taken up in 500 ml of chloroform and the mixture is filtered. The filtrate is evaporated in vacuo and the residue is chromatographed on 250 g of silica gel (chloroform-methanol 4: 1) to give 9.62 g (98%) of 4 (S) -hydroxymethylazetidine-. . 2-one as a white solid. Sp. 51-53 ° C; = + 68.0 ° (c = 2.676, CHCl 3); IR (CHCl 3): 3410, 1765 cm -1; ; 1 H NMR (CDCl 3): δ 7.07 (1H, br. S, NH), t 4.05 (1H, br.

s, OH), S 3.77 (2H, m H4, H-5a or b), <$ 3.58 (1H, dd, 25 J = 11.6, H-5a or b), Cf 2.97 (1H, ddd, J = 14.5, 4.8 1.3, H3b), ¢ 2.7 (1H, br. D, J = 14.5, H3a); mass spectrum m / e 101 (M +), 83.

Step C

0 30 OH.-F "OSCH3 Π -> —n °

c / «H

4 (S) -4-Methanesulfonyloxymethylazetidin-2-one 33 Methanesulfonyl chloride (11.46 g, 100 mmol) is added dropwise via syringe at 0 ° C to 4 (S) -4-hydroxymethylazetidin-2-one (10.1 g, 100 mmol) and triethyl, 9,78071 amine (10.1 g, 100 mmol) in 15 mL of dry methylene chloride. (Heating must be used to initially dissolve the alcohol. The resulting solution is then cooled to 0 ° C before the addition of the other reagents). The solution is stirred at 0 ° C for 1 hour to form a bulky precipitate. The reaction mixture is then filtered and the filtrate is evaporated in vacuo. The two solid residues are combined, 500 ml of chloroform are added. The mixture is filtered to give substantially pure 4 (S) -methanesulfonyloxymethyl-azetidin-2-one as a white solid. The filtrate, which contains most of the triethylamine hydrochloride, is concentrated in vacuo and chromatographed on 200 g of silica gel (chloroform-methanol 4: 1) to give 15 more mesylates. This batch is combined with that obtained previously and crystallized from chloroform to give 15.57 g (87%) of 4 (S) -4-methanesulfonyloxymethylazetidin-2-one as colorless needles. Sp. 109.5-110.5 ° C; [Α] D = + 25.8 ° (c = 1.025, H 2 O); NMR (D 2 O): λ 4.62 (1H, dd, J = 11.2, 3.0, H-5a or b), δ 4.43 (1H, dd, J = 11.2, δ , H-5a or b), δ 4.12 81H, m 4H), rf 3.26 (3H, s, O -SCH-), δ 3, Ί9 (1H, dd, J = 15, 4.5, H3b), tf 2.88 (1H, dd, tl 305 J = 15, 2.5, H3a); mass spectrum m / e 179 (M +), 136.

Analysis calculated for C 33.51, H 5.06, N 7.82, S 17.89 Found: C 33.54, H 5.08, N 7.72, S 17.93

Step D q 30 I- ^ ° iCH3 I-Λ *

N O acetone _N

S \ XH

o H OH

4 (S) -4-Iodomethylazetidin-2-one 35 A mixture of 4 (S) -4-methanesulfonyloxyazetidin-2-one (11.8 g, 65.9 mmol) and powdered sodium iodide (19.8 g, 132 mmol) 130 in 1 ml of acetone is heated to reflux for 20 hours. The reaction mixture is concentrated in vacuo, 200 ml of chloroform are added to the residue, and the mixture is filtered.

The filtrate is washed with 2 x 50 ml of water and dried over magnesium sulfate. The organic phase is filtered, evaporated in vacuo and chromatographed on 250 g of silica gel (ethyl acetate) to give 11.94 g (86%) of 4 (S) -4-iodomethylazetidin-2-one as a white solid. It is crystallized from ether-petroleum ether to give white crystals. Sp. 91-92 ° C; Δ = -23.7 ° (c = 1.354, CHCl 3); IR (CHCl 3): 3450, 1765 cm -1, 1 H NMR (CHCl 3): δ 6.13 (brs, NH), δ 3.94 (m, 1H, He), 3.36 (m, 2H, Hd and e ), £ 3.16 (ddd, kH, J = 14.9, 5.4, 2.3, Ha), 2.72 (d, d, d, 1H, J = 14.9, 15 2, 1, 2, Hb), mass spectrum me / e 211 (M +) 168, 142, 127, 84.

Example 2 Preparation of (4S) -1- (tert-butyldimethylsilyl) -4-iodomethylazetidin-2-one.

O υ Si- ττ / \ 11 25 To an ice-cold stirred solution of (4S) -4-iodomethylazetidin-2-one (10.0 g, 47.4 mmol) and triethylamine (5.04 g, 49.8 mmol) in anhydrous dimethylformamide (100 mL) is added tert-butyldimethylchlorosilane (7.51 g, 49.8 mmol) in one portion.

30 A white bulky precipitate is formed almost immediately.

The reaction mixture is stirred for 1 hour at 0-5 ° C, then allowed to warm to room temperature. Most of the solvent is removed in vacuo, and the resulting residue is treated with diethyl ether (250 mL) and water. The ether-35 phase is washed with 2.5 N hydrochloric acid, (50 ml), water (3 x 50 ml) and brine, dried over magnesium sulphate, filtered and evaporated in vacuo to give a white solid (4S) -1- ( tert-butyldimethylsilyl) -4-iodomethylazetidin-2-one (15.1 g).

Recrystallization from petroleum ether-ether mixture 5 gives colorless plates, m.p. 71-72 ° C; NMR (CDCl 3: δ $ 3.8 (m, 1), 2.6-3.6 (2 superimposed d, AB, 4), {$ 1.0 (s, 9), δ 0.3 (s , 6) <$ 0.25 (s, 6).

Example 3 Preparation of (4S) -1- (tert-butyldimethylsilyl) -N- [2,2,2-tri-10 (methylthio) ethyl] azetidin-2-one; ° 3 n-Butyllithium (19.4 ml of a 2.5 M hexane solution, 48.5 mmol) is slowly added via syringe to a solution of tri (methylthio) methane (7.47 g, 48.5 mmol) in freshly charged tetrahydrofuran. (150 ml) at -78 [deg.] C. The solution is stirred at -78 [deg.] C. for 30 minutes, after which (4S) -1- (tert-butyldimethylsilyl) -4-iodomethyl-azetidin-2-one (15, 0 g, 46.15 mmol) in 50 mL of tetrahydrofuran The solution is stirred at -78 ° C for 30 min, then saturated aqueous NH 4 Cl is added.

The reaction mixture is allowed to warm to room temperature, poured into ether (250 ml), the ether phase is washed with water (2 x 100 ml), brine (100 ml) and dried over magnesium sulphate. The solvents are removed in vacuo and the residual oil is crystallized from petroleum ether to give 13.3 g (82%) of (4S) -1- (tert-butyldimethylsilyl) -N-1,2-tri (methylthio) ethyl-7-azetidine- 2-ones as colorless prisms, m.p. 61-62 ° C. IR (CHCl 3, cm -1): 2918, 2850, 1730; NMR (CDCl 3): δ A, 0 (m, 1), δ 3.35 (dd, 1.35 J = 5.5, 16), δ 2.83 (dd, 1, J = 3.16) , tf 2.5 (ABq), </ 2.15 (s, 9), δ 0.98 (s, 9), </ 0.25 (s, 6).

22 7 8 0 71

Example 4 Preparation of (3S, 4R) -1- (tert-butyldimethylsilyl) -1-hydroxyethyl_7- [2,2,2-tri (methylthio) ethyl] azetidin-2-one. / CH3 H? SCH3 - / ^ £ SCH3 J 'SCH3 * ECH-j 0 / \ ~ 0' \ T v 10 n-butyllithium (14.8 ml of a 2.5 M hexane solution, 37.0 mmol) is added at -78 ° C syringe to a solution of diisopropylamine (3.74 g, 37.0 mmol) in 180 mL of freshly distilled tetrahydrofuran. Solution 15 is stirred at -78 ° C for 15 min, then (4S) -1- (tert-butyldimethylsilyl) -4- [1,2,2-tri (methylthio) ethyl] azetidin-2-one (12, 34 g, 35.16 mmol) in 35 ml of tetrahydrofuran. The solution is stirred at -78 ° C for 10 min, then acetaldehyde 20 (4.62 g, 105 mmol) is added. The solution is stirred for a further 5 min at -78 ° C, then saturated aqueous NH 4 Cl is added and the mixture is allowed to warm to room temperature. The mixture is poured into 250 ml of ether, washed with water (2 x 100 ml) and brine and dried over magnesium sulfate. The solvents are evaporated in vacuo and the residual oil is chromatographed on a silica gel column (ether-petroleum ether 1: 1) to give (3S »4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1-hydroxyethyl] -4- [2,2,2-tri (methylthio) ethyl] -azetidin-2-one (7.0 g, 40.4%); Rf = 0.2. The product can be recrystallized from petroleum ether. Alternatively, the trans-R product can be isolated from the reaction mixture by crystallization directly from petroleum ether solution.

23 7 8 0 71

Example 5 Preparation of (3S, 4R) -1- (tert-butyldimethylsilyl) -3- (1-oxoethyl) -4- [2,2,2-tri (methylthio) ethyl] azetidin-2-one_____ 5 e * - u O HO r ...

ö \ .4- o 'si-f · o N s-4-

Si-N / butyllithium (2.43 ml of a 2,4-M solution, 5.84 mmol) is added at -78 ° C via syringe to di-isopropylamine (591 mg, 5, 84 mmol) in 25 ml of freshly distilled tetrahydrofuran. The resulting solution is stirred at -78 ° C for 15 min, then (4R) -1- (tert-butyldimethylsilyl) -4- / 2,2,2-tri- (methylthio) ethyl / azetidin-2-one ( 1.00 g, 2.85 mmol) in tetrahydrofuran (5 mL). The solution is stirred at -78 ° C for 15 min, then passed through a Teflon tube into a mixture (-78 ° C) of N-acetylimidazole (642 mg, 5.84 mmol) and tetrahydrofuran (25 mL). The resulting yellow reaction mixture is stirred at -78 ° C for 10 min, then saturated aqueous NH 4 Cl is added. The mixture is diluted with ethylene. (200 mL) and washed with 2.5 N hydrochloric acid solution (50 mL), water (50 mL) and brine (50 mL) and dried over magnesium sulfate. The solvents are evaporated in vacuo, the yellow oil obtained is chromatographed on silica gel (ether-petroleum ether 30:70) to give (3S, 4R) -1- (tert-butyldimethylsilyl) -3- (1-oxoethyl) -4- / 2.2 , 2-tri (methylthio) ethyl / azetidin-2-one. N MR (CDCl 3): c 4.42 (m, 1), δ 4.32 (d, 1), 02.35 (m, 2), ε 2.32 (s, 3, f 2.2 (s , 9), £ 0.98 (s, 9), 35 cf 0.3 (2s, 6).

24 78071 B. To a solution of dimethyl sulfoxide (2.53 mmol) in dry methylene chloride (5 mL) at -78 ° C is added trifluoroacetic anhydride (400 mg, 1.905 mmol) via syringe. The mixture is stirred at -78 ° C for 30 min, then (3RSt4R) -1- (tert-butyldimethylsilyl) -3 - [(RS) -1-hydroxyethyl] -4 - [? 2-Tri (methylthio) ethyl * 7-azetidin-2-one (500 mg, 1.27 mmol) in dry CH 2 Cl 2 (1 mL) The resulting solution was stirred for 30 min, then triethylamine (360 mg, 3.56 mmol) was added. After 40 min, the reaction mixture is diluted with CH 2 Cl 2, washed with water and brine, and dried over magnesium sulfate, and the solvents are removed in vacuo to give an oil which is purified as above, yield 432 mg (86%).

Example 6 Preparation of (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - [(4) -1-hydroxyethyl] -4- [2,2,2-tri (methylthio) ethyl] azetidin-2-one 20 0 u SCH3 ho l J. 1scH3 *, Kh "3 K-Selectride® (3.64 mL 0.5-m, 1.82 mmol) is added via syringe at room temperature with potassium iodide (126 mg, 0.758 mmol) and (3S, 4R) -1- (tert-butyldimethylsilyl) -3- (1-oxoethyl) -4- / 2,2,2-tri (methylthio) ethyl / azetidin-2-one (298 mg, 0.758 mmol) in freshly distilled ethyl ether ( The resulting mixture was stirred at room temperature for 2.5 hours, then acetic acid (218 mg, 3.64 mmol) was added and the mixture was diluted with ethyl acetate (25 mL) and filtered.

Through Celite. The solvents are removed in vacuo, the resulting oil is chromatographed on silica gel (ether-petroleum ether) to give 252 mg of (3S, 4R) -1- (tert-butyl-dimethylsilyl) -3- [J [R] -1-hydroxyethyl ^ -4- ^ 2,2,2-tri- (methylthio) ethyl-azetidin-4-one. NMR (R-isomer, δ CDCl 3 + D 2 O): δ 4.15 (dq, 1), δ $ 3.95 (ddd, 1, J = 9.5, 2.3), δ 3.2 δ (dd , 1, J = 8, 2,3, <S 2.37 (m, 2), <$ 2.16 (s, 9), <$ 1.37 (d, 3, J = 6, 6), < $ 1.0 (s, 9), <$ 0.26 (s, 6).

Example 7 Preparation of (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - ((R) -1-10 hydroxyethyl) -4-carbomethoxymethylazetidin-2-one__

HO SCH3 HO

"" 'FCfe— 1 O / \ «

Mercury chloride (12.37 g, 45.6 mmol) is added in one portion at 0 ° C to a solution of (3S, 4R) -1-20 (tert-butyldimethylsilyl) -3 - [(R) -1- hydroxyethyl 7 '- 4 - [(2,2,2-tri (methylthio) ethyl] azetidin-2-one (6.0 g, 15.2 mmol) in 250 mL of anhydrous methanol. The resulting mixture (heavy white precipitate) was stirred. Sodium bicarbonate (8.99 g, 107 mmol) is added at 0 [deg.] C. The mixture is filtered, the solid is washed with methanol, the combined filtrate and washings are evaporated in vacuo and ethyl acetate and saturated aqueous NH4Cl are added to the residue, shaken. , and the organic phase is separated, washed with saturated aqueous NH 4 Cl, water and brine and dried over magnesium sulfate, the solvent is evaporated in vacuo and the resulting oil is chromatographed on a silica gel column (cyclohexane: ethyl acetate 3: 2) to give (3S, 4R) -1 tert-butyldimethylsilyl) -3 - ((R) -1-35 hydroxyethyl) -4-carbomethoxymethylazetidin-2-one.

26 7 8071

Example 8 Preparation of (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1- (tert-butyldimethylsilyloxy) ethyl] -4-carbomethoxymethylazetidin-2-one

5 I

HO 4-SiO

I I

'^' 'r-Y ~' CO 2 Ca 3_ ^ / 'v / \ CO 2 CH 3

o ^ si-h <> / V

10 tert-Butyldimethylchlorosilane (940 mg, 6.25 mmol) is added at 0 ° C in one portion of (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1-hydroxyethyl] To a solution of 4-carbomethoxymethylazetidin-2-one (1.88 g, 6.25 mmol) and triethylamine (1.27 g, 6.25 mmol) in 15 mL of anhydrous dimethylformamide.

After 15 minutes, the cooling bath is removed and the reaction mixture is stirred at room temperature for 24 hours. Ether (100 mL) is added to the mixture, and the mixture is filtered, washed with 2.5 N hydrochloric acid (20 mL), water (3 x 20 mL), and brine. The organic phase is dried over magnesium sulfate and evaporated in vacuo. The residue is chromatographed on silica gel (petroleum ether-ether 7: 3) to give (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1-tert-butyldimethylsilyloxy) -ethyl] /. 4-carbomethoxymethyl-2-one. NMR (CDCl 3): δ 4.3, 2.7 (m, 2), δ 3.68 (s, 3), δ 3.03 (dd, 1, J = 4, 3, 2, 7), ^ 2.8 (ABq, 2), <δ 1.17 (d, 3, 30 J = 6.6), δ 0.98 (s, 9), δ 0.89 (p. 9), δ , 23 (s, 6), S 0.1 (s, 6).

27 7 8 0 71

Example 9 Preparation of (3S, 4R) -1- (tert-butyldimethylsilyl) -3- (R) -1- (tert-butyldimethylsilyloxy) ethyl] -4- (2-oxoethyl) azetidin-2-one

5 l ». J

~ rSi ° -f "si0 H

O ^ 'si-f- 0 10

Diisobutylaluminum hydride (3.72 ml of a 0.91 M solution in hexane, 3.38 mmol) is added slowly at -78 ° C via syringe (3S, 4R) -1- (tert-butyldimethylsilyl) -3- / * To a solution of (R) -1- (tert-butyldimethylsilyloxy) -15 ethyl / -4-carbomethoxymethylazetidin-2-one (936 mg, 2.26 mmol) in 25 mL of freshly distilled toluene. The solution is stirred at -78 ° C for 3 hours, then 2.5N hydrochloric acid (5 ml) is added. The resulting mixture is stirred for 2 min, then the mixture is poured into a separatory funnel containing 100 ml of ether and 50 ml of 1.25 N hydrochloric acid saturated with tartaric acid. The organic phase is separated and the aqueous phase is extracted with ether (2 x 50 ml). The combined organic phases are washed with brine and dried over magnesium sulfate. The solvent 25 is removed in vacuo, the resulting white crystalline material is recrystallized from ether petroleum ether to give (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1- (tert-butyldimethylsilyloxy) ethyl] -4- (2-oxoethyl) azetidin-2-one. Sp. 115-116 ° C; NMR (CDCl 3): 64.1 (m, 1), δ 4.03 (m, 1), & 2.7-3.2 (m, 3), δ 1/23 (d, 3, J = 6 , 4), S 1/08 (s, 9), <5 0.9 (s, 9), 60.25 (s, 6), δ 0.1 (s, 6), δ 9.83 (t = 1. J = 1, 4).

78071 28

Example 10 (3S, 4R) -1- (tert-Butyldimethylsilyl) -3 - [(R) -1- (tert-butyldimethylsilyloxy) ethyl] -4- (3-benzyloxycarbonyl-2-hydroxypropyl) -azetidine-5 Preparation of 2-one___________ III I.

H — EiO “ElO

- ^ N: ho _ ^ ° H

n-butyllithium (1.81 mmol) is added via syringe to a solution of diisopropylamine (1.81 mmol) in freshly distilled tetrahydro-furan. The solution is stirred at -78 ° C for 15 min.

Benzyl acetate (1.81 mmol) is then added dropwise via syringe and the solution is stirred at -78 ° C for 20 min. (3S, 4R) -1- (tert-Butyldimethylsilyl) -3 - [(R) -1-20 (tert-butyldimethylsilyloxy) ethyl] -4- (2-oxoethyl) azetidin-2-one is slowly added via syringe via syringe. (1.64 mmol) solution in 3 ml: anhydrous tetrahydrofuran. The reaction mixture is stirred at -78 ° C for a further 15 min, then saturated aqueous NH 4 Cl 2 is added. Ethyl acetate (50 mL) is added to the mixture, and the organic phase is separated, washed with water (2 x 10 mL) and brine, and dried over magnesium sulfate. The solvent is evaporated in vacuo and the white solid obtained is chromatographed on a short column of silica gel (ether: petroleum ether 40:60) to give 30 (3S, 4R) -1- (tert-butyldimethylsilyl) -3- (R) -1- (tert-butyldimethylsilyl). .-butyldimethylsilyloxy) ethyl-4- (3-benzyloxycarbonyl-2-hydroxypropyl) azetidin-2-one. NMR (CDCl 3): δ 7.32 (s, 5), δ 5.1 (s, 2), 4.0 (m, 3), δ 2.4-3.8 (m, 4), δ, 0 (m, 2), 51.25 (overlapping d, 3), 35 5 0.95 (s, 9), $ 0.9 (s, 9), «f 0.3 (s, 6, cfo , 18 (s, 6).

29 78071

Example 11 (3S, 4R) -1- (tert-Butyldimethylsilyl) -3 - [(R) -1- (tert-butyldimethylsilyloxy) ethyl] -4- [3- (4-nitrobenzyl) oxycarbonyl-2 -hydroxypropyl-5-azetidin-2-one preparation__-f-sio + f °.

U 2 O 2 O 2 -CH 2 -CH-® -No 2 (3S, 4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1- (tert-butyldimethylsilyloxy) ethyl] -4) 3- benzylcarbonyl-2-hydroxypropyl) azetidin-2-.

A mixture of 15 onions (1.00 mmol), sodium bicarbonate (1.00 mmol) and 10% Pd / C in 20 ml of a 4: 1 mixture of tetrahydrofuran and water is hydrogenated at 276 kPa on a Parr shaker for 30 minutes. The mixture is filtered through Celite and the catalyst is washed with 10 ml of water.

The combined washings and filtrate are evaporated in vacuo to 2 ml and lyophilized. The resulting light white solid is dissolved in 5 mL of anhydrous dimethylformamide and p-nitrobenzyl bromide (216 mg, 1.00 mmol) is added in one portion. The resulting solution was stirred at room temperature for 3 hours, then ether (50 mL) was added and the solution was washed with water (3 x 10 mL) and brine and dried over magnesium sulfate. The solvent is evaporated in vacuo and the residue is chromatographed on silica gel to give (3S, 4R) -1- (tert-butyldimethylsilyl) -3- (10-1- (tert-butyldimethylsilyloxy) ethyl) -4- [3- (4 -nitrobenzyl) -oxycarbonyl-2-hydroxypropyl] -azetidin-2-one NMR (CDCl 3) δ δ 7.85 (2d-aromatic, δ) δ 5.26 (s, 2), δ 4.2 (m , 3), cf 2.5-3.6 (m, 4), </ 2.0 35 (m, 2), 1, 4 (2 overlapping d, 3), of 1.0 (2s, 18 ), cf 0.25 (2s, 12).

3o 7 8071

Example 12 (3S, 4R) -1- (tert-Butyldimethylsilyl) -3 - [(S) -1- (tert-butyldimethylsilyloxy) ethyl] -4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl] azetidin-5 Preparation of 2-one__

Ή5 iO -f SiO

^ CO-, ρΝΒ Jr-N kCO, -CH, - @ - NO, 10 sSi, ^ 2 ^ ° CT "61+ 2 2 ^ 2 I / \

Anhydrous chromium trioxide (10.0 mmol) is added to a solution of anhydrous pyridine (20.0 mmol) in 30 ml of anhydrous methylene chloride. The mixture is stirred at room temperature for 15 min, then (3S, 4R) -1- (tert-butyldimethylsilyl) -3-f (R) -1- (tert-butyldimethylsilyloxy) ethyl] -N-4- [3- A solution of (4-nitrobenzyl) oxycarbonyl-2-hydroxypropyl} -azetidin-2-one (1.00 mmol) in anhydrous methylene chloride (8 mL). The mixture is stirred at room temperature for 5 min, the Cl 2 Cl 2 layer is decanted over a dark, tarry residue which is then triturated with another portion of Cl 2 Cl 2. The combined Cl 2 Cl 2 phases are evaporated in vacuo. The residue is triturated in ether (100 ml) and the ether solutions are filtered. The filtrate is washed with 5% aqueous sodium bicarbonate, 2,5-N hydrochloric acid, 5% NaHCO 3 and brine, dried over magnesium sulfate and evaporated in vacuo to give (3S, 4R) -1-tert-butyl-dimethylsilyl) - 3-, [(R) -1- (tert-butyldimethylsilyloxy) ethyl] -4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl] azetidin-2-one. NMR (CDCl 3): cf.6.6 (2d-aromatic, 4), cf 5.27 (s, 2), δ 4.05 (m, 2), cf 3.6 (s, 2), δ 2, 4-3.2 (dd overlapping ABq, 3), 35 d * 1.2 (d, 3, J = 6, 6), cfo, 9 (2 s, 18), (^ 0.22 (s, 6), <f0.5 (s, 6).

31 78071

Example 13 Preparation of (3S, 4R) -3 - [(r) -1-hydroxyethyl] -4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl] azetidin-2-one

5 -J-SiO HO

(2S, 4R) -1- (3Sf 4R) -1- (tert-butyldimethylsilyl) -3 - [(R) -1- (tert.- butyldimethylsilyloxy) ethyl-4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl] azetidin-2-one (7.9 mmol) is dissolved in 160 ml of a 9: 1 (v / v) aqueous methanol mixture and the solution is cooled. 0 ° C.

Concentrated hydrochloric acid (2.75 ml) is added to the solution, and the resulting solution is stirred at 0 ° C for 15 min, then allowed to warm to room temperature. The solution is stirred at room temperature for 2.5 hours, ethyl acetate (200 ml) is added, the organic phase is washed with water, saturated aqueous sodium bicarbonate solution and brine, dried over magnesium sulphate and evaporated in vacuo to give (3S, 4R) -3 - / * ) - 1-hydroxyethyl / -4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl] azetidin-2-one.

Example 14 Preparation of (3S, 4R) -S- (R) -1-hydroxyethyl--4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxo-3-diazopropyl] azetidin-2-one

30 HO HO

Λ-τγ Λ-τ-r ° p ^ COjPNB a> - «n- ^ CO 2 -CH 2 - <Ö> -NO 3 35 Triethylamine (263 mg, 2.6 mmol) is added at 0 ° C via syringe (3S, 4R) -3-Z "(R) -1-hydroxyethyl--4-Z" 3- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl-78071 32 azetidin-2-one (253 mg, 0.72 mmol) and p -carboxy-benzenesulfonyl azide (196 mg, 0.84 mmol) in dry acetonitrile (6 mL). At the end of the addition, the cooling bath is removed and the reaction mixture is stirred at room temperature for one hour. The mixture is then diluted with ethyl acetate (50 mL) and filtered. The filtrate is evaporated in vacuo and the residue is chromatographed on a short column of silica gel (ethyl acetate) to give 222 mg (81% overall yield (3S, 4R) -10 1- (tert-butyldimethylsilyl) -3- [1R) -1- (tert. - with respect to butyldimethylsilyloxy) ethyl [4 - [[4- (4-nitrobenzyl) oxycarbonyl-2-oxopropyl] azetidin-2-one] (3S, 4R) -3 H (R) -1-hydroxyethyl] -4- [3- (4- nitrobenzyl) oxycarbonyl-2-oxo-3-diatsopropyyli7atsetidin-2-one

15 as a white solid. Sp. 163 ° C (decomposes); IR

(CHCl 3, cm-1): 3410, 2132, 1756, 1718, 1650, 1350, 1280, 1120; NMR (CDCl 3): δ 7.9 (2d-aromatic, 4), (f 5.4 (s, 2), δ 6.2 (brs, 1), δ 4.1 (m, 2), δ 2.6-3.6 (m, 4), δ 1.32 (d, 3, J = 6.2).

Example 15 Preparation of (5R, 6S) -p-nitrobenzyl 6-7 (R) -1-hydroxyethyl-7-azabicyclo [3.2.07] heptane-3,7-dione-2-carboxylate__

25 H.0 HO

A suspension of (3S, 4R) -1-hydroxyethyl-4- [3- (4-nitrobenzyl) oxycarbonyl-2-oxo-3 -diazopropyl-7-azetidin-2-one (56.4 mg, 0.15 mmol) and rhodium (II) acetate (0.1 mg) in dry benzene (3 mL), deoxygenated under nitrogen for 10 min.

The mixture is then heated at 78 ° C for one hour. Upon heating, the starting material gradually dissolves. The mixture is cooled, the catalyst is filtered off and the filtrate is evaporated in vacuo to give 51 mg (98%) of (5R, 6S) -p-nitrobenzyl-β- (1R) -1-hydroxyethyl] -1-azabicyclo [* 3,2,0,7-Heptane-3,7-dione-2-carboxylate as a colorless oil which slowly crystallizes at room temperature (22 ° C). Physical properties

OH

Δ Γ ~ ΐ ^ Ύ ° 1 o Jr-yl-L co 2 -ch 2 -®-no 2 PNB = p-nitrobenzyl NMR: (300 MHz), CDCl 3): 8.26, 7.54 (aromatic, 4), 5.29 (AB, 2), 4.77 (s, 1), 4.32 (dq, 1, J = 6.6, 7) 4.16 (ddd, 1, J = 7, 7.5) , 2.2). 3.21 (dd, 1, J = 7, 2.2), 2.94 (dd, 1, J = 19.57), 2.50 (dd, 1, J = 19.5, 7.5) , 2.2 (brs, 1), 1.37 (d, 3, J = 6.6).

IR (CHCl 3, cm -1): 1770, 1758, 1610, 1522, 1353.

Sp. 110-111 ° C.

Example 16 Preparation of p-nitrobenzyloxycarbonylaminoethanolthiol HS / V ^ NH2-HCl + Cl-COCH2 - ^ ^ - NO2 o

25 _ ^ NHCO2PNB

To a stirred mixture of diethyl ether (Et 2 O) (600 mL) and water (75 mL) is added 3.2 g of cystamine hydrochloride (m.p. 114, 28.1 mmol) in an ice bath with stirring. To the solution is added 7.14 g of NaHCO 3 (m.p. 84, 85 mmol) in 75 ml of water.

The ice bath is removed and a solution of p-nitrobenzyl chloroformate (6.75 g, m.p. 216, 31.3 mmol) in 270 ml of diethyl ether is added dropwise over 1 hour at room temperature. After 10 minutes, the layers are separated. The ether layer is extracted with 150 ml of 0.25 N hydrochloride-34,78071 solution and then with 200 ml of brine. The aqueous solutions are then extracted each with 100 ml of diethyl ether. The combined ether layers are dried over anhydrous magnesium sulfate, filtered and evaporated.

The crystalline residue is slurried in a small amount of ether, filtered, and the pale yellow crystals are dried under high vacuum to give 4.7 g of p-nitrobenzyloxycarbonylaminoethanolthiol (65% yield).

NMR (CDCl 3): 8.18 (d, J = 8 Hz, aromatic protons in the 10 o position relative to the nitron), 7.47 (d, J = 8 Hz, aromatic protons in the m position relative to the nitron), δ , 27 (-NH-), 5.20 (s, -Cl 2 -NH-), 2.67 (m, -CH 2 -SH), 1.35 (t, J = 8.5 Hz, -SH) ppm, downward relative to TMS. IR (CHCl 3): carbonyl- 1725 cm -1. Mass spectrum: molecular ion-256, 15 (M-47) 209, (M-136) 120, + CH 2 O 2 NO 2 126.

Example 17 (5R, 6S) -p-Nitrobenzyl-3- [2- (p-nitrobenzyloxycarbonyl) aminoethylthio, -6 - [(R) -1-hydroxyethyl] -1-azabicyclo [3.2.07] Preparation of hept-2-en-7-one-2-carboxylate_20

OH 0H

i — NL CO 2 PNB CQ 2 -CH 2 - <O 2 -NO 2 25 (5R, 5S) -p-Nitrobenzyl-6 - [(R) -1-hydroxyethyl] -1-azabicyclo / 3.2.07-heptane-3 The 7-dione-2-carboxylate (51 mg, 0.147 mmol) is dissolved in acetonitrile (3 mL) and the resulting solution is cooled to 0 ° C. To the solution 30, diisopropylethylamine (22 mg, 0.17 mmol) is added via syringe and the solution is stirred at 0 ° C for 1 minute, then freshly crystallized p-toluenesulfonic anhydride (51 mg, 0.156 mmol) in dry acetonitrile (1 mL) is added. The resulting solution containing the intermediate (which can be isolated) (5R, 6S) -35 78071 p-nitrobenzyl-3- (p-toluenesulfonyloxy-6- / T (R) "1" hydroxyethyl azabicyclo-3,2,0,7hept-2-en-7-one-2-carboxylate, stirred at 0 ° C for 1 hour, then the solution is cooled to -25 ° C. isopropylethylamine (80.5 mg, 0.624 mmol) and shortly thereafter a solution of Np-nitrobenzyloxycarbonylcystamine (40 mg, 0.156 mmol) in 1 mL of dry acetonitrile The reaction mixture was allowed to stand in the refrigerator for 70 h, diluted with 25 mL of ethyl acetate. The solvent is evaporated off in vacuo and the yellow oil obtained is chromatographed on a silica gel plate (ethyl acetate, = 0.4) to give (5R, 6S) -3 - [(2-p-nitrobenzyloxycarbonyl) aminoethylthio./-6- (R) -1-15 hydroxyethyl N-azabicyclo [3.2-0] hepten-7-one 2-carboxylate as a yellow solid, m.p. 167-169 ° C. IR (Nujoi) 1773 and 1690 cm -1; NMR (CDCl 3) δ 7.54-8.62 (overlapping ABq, 4), δ 5.40 (ABq, 2), δ $ 5.22 (s, 2), δ 4.27 (m, 2), <δ 3.47 (m), cJ3.23 (dd, 1), δ <53.14 (dd, 1), <i3.40 (dd, 1), <53.04 (m, 2), cil, 37 (d, 3).

Example 18 Preparation of thienamycin

25 OH OH

/ k ™ C ° 2PNB

0J-N - * - CO2PNB ^ 0 ^ ”N -c ° 2H

30 Np-nitrobenzyloxycarbonylthienamycin p-nitrobenzyl ester (10 mg, 0.017 mmol) and 10% Pd / C catalyst (Bolhofer type) (in tetrahydrofuran, 2 mL), 0.1 M dipotassium hydrogen phosphate solution (1.4 mL) and 2 -propanol (0.2 ml) is hydrogenated at 276 kPa in a Parr shaker for 30 minutes. The mixture is filtered and the catalyst is washed with water (3 x 3 ml). The filtrate and washings are combined and extracted with ethyl acetate-ethyl ether and evaporated to 3 ml and lyophilized. The white powder obtained is identical in all respects to natural thienamycin.

5

Claims (4)

37 7 8 0 71 An intermediate for the preparation of thienamycin, starting from L-aspartic acid of the formula ^ -NR111010 wherein R1 is a protecting group such as a tert-butyldimethylsilyl group. 2. An intermediate used in the preparation of thienamycin starting from L-aspartic acid of the intermediate formula OH Λ-τν », J - NR1 SR O wherein R · * - is a protecting group such as tert-butyldimethylsilyl and R is lower alkyl group. 3. An intermediate for the preparation of thienamycin starting from L-aspartic acid of the formula OH Λ-υΎ - »-NH 1 -CO 2 R wherein R 1 is a protecting group such as p-nitrobenzyl. 4. An intermediate used in the preparation of thienamycin starting from L-aspartic acid of the formula qh Λ-vi1 35 7 -NH CO 2 R 'N 2 i 7 wherein R is a protecting group such as p-nitrobenzyl.