NZ208649A - A method of producing cephalosporin derivatives - Google Patents

Description

New Zealand Paient Spedficaiion for Paient Number £08649 208649 Priority Date(s]< Complete Specification Filed: Class: f. F.1&S9. i(o^oC Publication Date: ..$9. 3??® P.O. Journal, No: .

Patents Form No. 5 NEW ZEALAND PATENTS ACT 1953 COMPLETE EPECIFICATION "METHOD OF PRODUCING CEPHALOSPORIN DERIVATIVES" ^WE KYOTO PHARMACEUTICAL INDUSTRIES, LTD., of 38, Nishinokyo, Tsukinowa-cho, Nakakyo-ku, Kyoto-shi, Kyoto, Japan, a Japanese company, hereby declare the invention, for which 2riwe pray that a patent nay be granted to jb€/us, and the method by which it is to be performed, to be particularly described in and by the following statement:- (followed by Page 1A) - l A - 208649 SPECIFICATION Method of Producing Cephalosporin Derivatives TECHNICAL FIELD This invention relates to methods of producing novel cephalosporin derivatives and salts thereof.

BACKGROUND OF THE INVENTION, PRIOR ART The present inventors have previously developed novel cephalosporin derivatives (I) of the general formula CH-CONH , S > N N I O I N ^1—CH^-S 2 - 3 ? ° 0 COOH_ (I) CH-NH0 I 2 CH3 2 wherein R is hydrogen or hydroxyl, and salts thereof (cf.New Zealand patent-specification No. 206019). Said cephalosporin derivatives (I) and salts thereof are excellent in absorbability through the digestive tract. After absorption, they are rapidly converted to the unesterified compounds corresponding to the cephalosporin derivatives (I), namely the compounds of the general formula R2_Y' x>—CH-CONH Jtl-UUNH ■ II I U OH ff "Alj-S^SA, (II) O ' ^ COOH 2 -6 JUN1986"f s/t> // ^ n 208649 wherein R is as defined above, as a result of in vivo enzymatic hydrolysis of the carboxylate ester moiety at the 4-position of the cephem ring and of the amino acid ester moiety at the a-position on the 7-position side chain. Thus, oral administration of the cephalosporin derivatives (I) can result in high blood levels of the unesterified forms which have excellent antimicrobial activity. Therefore, the cephalosporin derivatives (I) and salts thereof are very excellent antibiotics.

The present inventors conducted an intensive and extensive study in search of an improved method of producing said novel cephalosporin derivatives (I) and salts thereof and found that the methods described below can afford the cephalosporin derivatives (I) and salts thereof in an efficient manner. This finding has now led to completion of the present invention.

OBJECTS AND DISCLOSURE OF THE INVENTION Accordingly, an object of the invention is to provide certain methods of producing the cephalosporin derivatives (I) and salts thereof.

Another object is to provide intermediates for the production of the cephalosporin derivatives (I) and salts thereof [namely, the compounds (V) to be described herein-below] and methods of producing the same.

In accordance with the invention, the cephalosporin derivatives (I) and salts thereof are produced in the 208649 following manner: (Process 1) This process involves the reaction of a compound of the general formula r2 / \_ch_c00h O I C=0 (III) I CH-NH„ I 2 CH3 2 wherein R is as defined above, with a compound of the formula ' NH, (IV) The compound (III) is submitted to this reaction in the form of free carboxylic acid, in the form of an alkali metal salt or in the form of a reactive derivative thereof. Thus, it is submitted to said reaction in the form of free acid, in the form of a salt such as the sodium, potassium, calcium, triethylamine or pyridine salt, or in the form of a reactive derivative thereof, such as an acid halide (e.g. acid chloride, acid bromide), an acid anhydride, a mixed acid anhydride [e.g. with a substituted phosphoric acid (e.g. dialkylpho^phoric acid), an alkylcarbonic acid 208649 (e.g. monoethylcarbonic acid)], an active amide (amide e.g. with imidazole) or an ester (e.g. cyanomethyl ester, 4-nitrophenyl ester).

When the compound (III) is used in the free carboxylic acid form, an appropriate condensing agent is preferably used. As the condensing agent, there may be used a dehydrating agent, such as an N,N'-disubstituted carbodi-imide (e.g. N,N'-dicyclohexylcarbodiimide) or an azolide compound (e.g. N,N1-carbonyldiimidazole, N,N'-thionyldi-imidazole). When such condensing agent is used, the reaction presumably proceeds via a reactive derivative of the carboxylic acid.

The above reaction is generally carried out in an inert solvent. Examples of the solvent are water, organic solvents, such as acetone, dioxane, acetonitrile, chloroform, benzene, methylene chloride, ethylene chloride, tetrahydrofuran, ethyl acetate, N,N'-dimethylformamide and pyridine, and mixture of these.

The reaction is preferably conducted at -20°C to 35°C. (Process 2) In this process, a compound of the general formula CH-CONH CH2-S N N O // CH 3 0 COOCH CH c=o 3 (V) 1 0 o CH-NH-R CH O 3 2086 4 9 wherein R1 is formyl, t-butoxycarbonyl, l-methyl-2-methoxy- carbonylvinyl, l-methyl-2-ethoxycarbonylvinyl, benzyloxy- carbonyl, p-methoxybenzyloxycarbonyl, chloroacetyl, trityl, 2 silyl or 2,2,2-trichloroethoxycarbonyl and R is as defined above, is subjected to an amino-protecting group elimination reaction.

Referring to r\ the silyl represented thereby includes, among others, trialkylsilyl, dialkylalkoxysilyl and trialkoxysilyl groups, in which each alkyl is preferably a lower alkyl containing 1-4 carbon atoms, such as methyl, ethyl or propyl, and alkoxy is preferably a lower alkoxy containing 1-4 carbon atoms, such as methoxy, ethoxy or propoxy.

The elimination reaction may be carried out in the manner, for example in the manner of hydrolysis or reduction. (1) Hydrolysis: The hydrolysis is desirably conducted in the presence of an acid.

As the acid, there may be mentioned inorganic acids (e.g. hydrochloric acid, hydrobromic acid, sulfuric acid), organic acids (e.g. formic acid, acetic acid, trifluoro-acetic acid, propionic acid, methanesulfonic acid, benzene-sulfonic acid, p-toluenesulfonic acid), acidic ion exchange resins, etc. When such organic acids as trifluoroacetic acid and p-toluenesulfonic acid are used, the reaction is preferably carried out in the presence of a cation acceptor 208649 (e.g. anisole). The hydrolysis is generally conducted in a conventional solvent which does not adversely affect the reaction, such as water, methanol, ethanol, propanol, tertiary-butyl alcohol, tetrahydrofuran, N,N-dimethy1form-amide , dioxane, acetone, methyl ethyl ketone or ethyl acetate, or a mixture of these. When the above-mentioned acid is a liquid, it may also serve as the solvent.

The hydrolysis reaction temperature is not particularly limited. (2) Reduction: The reduction is carried out in the conventional manner, such as in the manner of chemical reduction or catalytic reduction. Reducing agents suited for use in the chemical reduction are combinations of a metal (e.g. tin, zinc, iron) or a metal compound (e.g. chromium chloride, chromium acetate) and an organic or inorganic acid (e.g. formic acid, acetic acid, propionic acid, trifluoroacetic acid, p-toluenesulfonic acid, hydrochloric acid, hydro-bromic acid).

Conventional catalysts are suited for the catalytic reduction. Thus, for instance, platinum catalysts (e.g. platinum plate, platinum sponge, platinum black, colloidal platinum, platinum oxide, platinum wire), palladium catalysts (e.g. palladium sponge, palladium black, palladium oxide, palladium-on-carbon, colloidal palladium, palladium-on-barium acetate, palladium-on-barium carbonate), nickel catalysts (e.g. reduced nickel, nickel oxide, Raney 7 208649 nickel), cobalt catalysts (e.g. reduced cobalt, Raney cobalt), iron catalysts (e.g. reduced iron, Raney iron) and copper catalysts (e.g. reduced copper, Raney copper, Ullmann copper) may be used.

The reduction is generally carried out in a conventional solvent which does not adversely affect the reaction, such as water, methanol, ethanol, propanol or N,N-dimethylformamide, or a mixture of these. When the acid used in the chemical reduction is a liquid, it may also serve as the solvent. Suitable solvents for use in the catalytic reduction are diethyl ether, dioxane, tetra-hydrofuran and mixtures of these as well as the above-mentioned solvents.

The reaction temperature for this reduction is not particularly limited.

The elimination method is selected from among those mentioned above depending on the protective group to be eliminated.

The compounds (V) are novel compounds and are produced, for example, in the following manner: (Process 1) This process involves the reaction of a compound of the general formula C=0 (VI) CH-NH-R 1 CH 3 2 086 49 wherein R and R are as defined above, or a reactive derivative thereof with a compound of the formula NH 2n • I l-N CH2S N s N CH 3 (VII) 0 | COOCH 2 CH 3 O O o The compound (VI) is submitted to the above reaction in the free carboxylic acid form or in the form of a reactive derivative. Thus, it is subjected to said acyla-tion reaction in the free acid form or in the form of a reactive derivative such as a salt with sodium, potassium, calcium, triethylamine, pyridine or the like, an acid halide (e.g. acid chloride, acid bromide), an acid anhydride, a mixed acid anhydride [e.g. with a substituted phosphoric acid (e.g. dialkylphosphoric acid, an alkylcarbonic acid (e.g. monoethylcarbonic acid)], an active amide (amide e.g. with imidazole) or an ester (e.g. cyanomethyl ester, 4-nitrophenyl ester).

When the compound (VI) is used in the free acid form, an appropriate condensing agent is preferably used. The condensing agent is, for example, a dehyrating agent such as an N,N'-disubstituted carbodiimide (e.g. N,N1-dicyclo-hexylcarbodiimide) or an azolide (e.g. N.N'-carbonyldi-imidazole, N,N'-thionyldiimidazole). When such condensing agent is used, the reaction presumably proceeds via a reactive derivative of the carboxylic acid. The reaction 208649 is generally conducted in an inert solvent. Examples of the solvent are water, acetone, dioxane, acetonitrile, chloroform, benzene, methylene chloride, ethylene chloride, tetrahydrofuran, ethyl acetate, N,N-dimethylformamide, pyridine or the like organic solvents, and mixtures of these.

The above reaction is generally carried out at -30°C to 50°C, preferably -20°C to 20°C.

The compound (VII) is produced, for example, by reacting a compound of the general formula R3-NH- 0 N N COOH 3 wherein R is hydrogen or an amino-protecting group, with a compound of the general formula X-CH2—p=i—CH3 O O (IX) 0 wherein X is a group reactive with a carboxyl group (or a reactive group derived therefrom). 3 Referring to R is general formula (VIII), the amino-protecting group includes those amino-protecting groups which are known per se, such as benzylcarbonyl, 2-thienyl-acetyl, 2-furylacetyl, D-5-amino-5-carboxyvaleryl, trityl, phthalimido, formyl, t-butoxycarbonyl, l-methyl-2-methoxy- 208649 carbonylvinyl and l-methyl-2-ethoxycarnonylvinyl.

Referring to general formula (IX) , the group reactive with a carboxyl group (or a reactive group derived therefrom) as represented by X is, for example, halogen (e.g. bromo, chloro, iodo), alkylsulfonyloxy (e.g. methan^sulfonyl-oxy) , arylsulfonyloxy (e.g. p-toluenesulfonyloxy) or hydroxyl.

The compound (VIII) is used in the free carboxylic acid form or in the form of a reactive derivative thereof. Thus, it is submitted to said acylation reaction in the free acid form or in the form of the same reactive derivative as mentioned with respect to the compound (VI).

When the compound (IX) is used in the form in which X is hydroxyl, an appropriate condensing agent may be used. The condensing agent to be used in that case may be the one mentioned hereinabove. When such condensing agent is used, the reaction presumably proceeds via a reactive derivative of the carboxylic acid.

This reaction is conducted generally at -30°C to 50°C, preferably -20°C to 20°C. 3 Said protective group (R ) can be eliminated by the per se known method.

The compound (VI) is produced, for example, by reacting a compound of the general formula (VI-1) OH 2 0 3 6 4 9 2 wherein R is as defined above, or a reactive derivative thereof with a compound of the general formula HOOC-CH-NH-.R I CH- (VI-2) J • wherein R is as defined above.

(Process 2) This process involves the reaction of a compound of the general formula R2 CH-CONH OH // CH.

(X) wherein R is as defined above, or a reactive derivative thereof with a compound of the general formula CH.

R -NH-CH-COOH (XI) ,1 ■ wherein R is as defined above.

The compound (XI) is submitted to the reaction either in the free carboxylic acid form or in the form of a derivative such as mentioned for the compound (VI).

When the compound (XI) is used in the free acid form, the use of an appropriate condensing agent is preferred. As the condensing agent, those mentioned hereinabove may 12 20864 be used. When such condensing agent is used, the reaction presumably proceeds via a reactive derivative of the carboxylic acid. In carrying out the reaction, a base, such as 4-dimethylaminopyridine, is preferably used as the catalyst. This reaction is carried out generally in an inert solvent. Examples of the solvent are water, organic solvents, such as acetone, dioxane, acetonitrile, chloroform, benzene, methylene chloride, ethylene chloride, tetrahydrofuran, ethyl acetate, N,N-dimethylformamide and pyridine, and mixtures of these.

The compound (X) is produced by reacting the compound (II) with the compound (IX) or by reacting the compound (VII) .with a compound of the general formula The compound (II) is preferably submitted to this reaction in the form of a reactive derivative (e.g. an alkali metal salt, such as sodium salt or potassium salt, an alkaline earth metal salt, such as calcium salt, an organic amine salt, Buch as triethylamine salt or pyridine salt).

This reaction is preferably carried out under cool- 2 ing so that the byproduct A -isomer formation can be (XII) II 0 2 wherein R is as defined above 2086 4 avoided. The use of a solvent which does not adversely affect said reaction (e.g. N,N-dimethylformamide, N,N-dimethylacetamide, hexamethylphosphoramide, acetone, acetonitrile, dimethyl sulfoxide, chloroform, methylene chloride) can facilitate the progress of the reaction. (Process 3) This process involves the reaction of a compound of the general formula S CH.

(XIII) CH-NH-R CH. 1 2 wherein R and R are as defined above, or a reactive derivative thereof with the compound (IX).

The compound (XIII) is submitted to the above reaction either in the free carboxylic acid form or in the form of a reactive derivative such as mentioned with respect to the compound (VI).

When the compound (IX) is used in the form in which X is hydroxyl, the use of a condensing agent such as mentioned above is preferred. When a condensing agent is used, the reaction presumably proceeds via a reactive derivative of the carboxylic acid. Bases, such as 4-dimethylaminopyridine, are preferred catalysts for use in conducting this reaction. 208649 The compound (XIII) is produced by reacting 7-amino-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylic acid (7-ACTD) with the compound (VI).

The compound (VI) is preferably submitted to said acylation reaction in the form of reactive derivative such as mentioned hereinabove.

The cephalosporin derivatives (I) can be converted, by the conventional means, to pharmaceutically acceptable acid addition salts, such as mineral acid salts (e.g. hydrochloride).

The cephalosporin derivatives (I) and salts thereof can be isolated and purified by the conventional methods.

The thus-produced cephalosporin derivatives (I) can be diluted with a pharmaceutical carrier or excipient by the per se known techniques to give therapeutic preparations for oral use which are useful in the treatment of bacteriacaused infectious diseases. The dilution is performed by the per se known means, for example, by mixing. Examples of the carrier or excipient are starch, anhydrous lactose, sugar, calcium carbonate and calcium phosphate.

Said oral preparations for use in treating infectious diseases caused by bacteria may further contain other additives as desired. Preferred additives are a binding agent (e.g. starch, gum arabic, carboxymethylcellulose, hydroxypropylcellulose, crystalline cellulose), a lubricant (e.g. magnesium stearate, talc) and a disintegrating agent 208649 (e.g. carboxymethylcellulose calcium, talc), among others. The necessary components are mixed and the mixture is processed, by the per se known methods, into dosage forms suited for oral administration, such as capsules, tablets, fine powder, granules, and dry syrup.

The dose of the cephalosporin derivatives (I) and salts thereof may vary depending on the subject to be treated therewith, the symptom and other factors. In treating suppurative diseases in adults, for instance, the cephalosporin derivatives (I) and salts thereof are administered orally about 1-4 times daily, for example, in a single dose of about 1-40 mg/kg of body weight as calculated on the corresponding unesterified form basis.

The following examples illustrate the invention in more detail. It is to be noted that they are by no means limitative of the invention.

In the examples, Boc means t-butoxycarbonyl.

Example 1 Synthesis of (5-methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-O-(L-alanyl)mandelamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)-thiomethyl-3-cephem-4-carboxylate hydrochloride Process (1): (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-amino-3- (5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate - (1.5 g) is dissolved in 45 ml of methylene chloride. Thereto is added 0.92 g of D-0-(L-alanyl)mandelic acid chloride hydrochloride at 0°C over 30 minutes, followed by stirring at room temperature 208649 overnight. The solid matter is collected by filtration and washed with methylene chloride to give 2.1 g of the title compound in a crude state. This is recrystallized from ethanol to give 1.7 g of the title compound.

Process (2); (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-O-(N-Boc-L-alanyl)mandelamide]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate (72 g) is dissolved in 700 ml of ethyl acetate, followed by blowing 7 g of hydrogen chloride gas into the solution at -5°C. The mixture is then stirred at 0°C for 30 minutes. The solid matter is collected by filtration and washed with isopropyl ether to give 66 g of the title compound in a crude state. Recrystallization from ethanol gives 56 g of the title compound.

Process (3): (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-O-(N-formyl-L-alanyl)mandelamide]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate (2 g) is dissolved in 50 ml of methanol, and 1.32 ml of concentrated hydrochloric acid is added. The mixture is stirred at room temperature overnight and then poured into isopropyl ether. The solid matter (precipitate) is collected by filtration and washed with isopropyl ether to give 1.7 g of the title compound in a crude state. Recrystallization from ethanol gives 1.2 g of the title compound. Process (4): (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-{D-O-[N-(l-methyl-2-ethoxycarbonylvinyl)-L-alanyl]mandel-amino}-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3- 17 2 086 4 9 ¥ cephem-4-carboxylate (5 g) is dissolved, in 30 ml of methanol. Thereto is added, at 0°C, 20 ml of 4 N hydrogen chloride in ethanol, followed by stirring at room temperature for 30 minutes. Diethyl ether is added to the reaction mixture and the resulting precipitate is collected by filtration and washed with diethyl ether to give 3.8 g of the title compound in a crude state. Recrystallization from ethanol gives 2.9 g of the title compound. Melting point: 158°C (decomposition).

IR (nujol, cm ^) ; 1815, 1760, 1690 NMR ((CD3)2SO, 6 value) ; 1.48 (d, 3H, J=7Hz, -CH-CH3) 2.18 (s, 3H, dioxole-CH3) 2.66 (s, 3H, thiadiazole-CH3) 3.62 (br^ s, 2H, 2-position-H2) I 4.2 (m, 1H, -CH-CH3) 4.07, 4.65 (d, d, 2H, J=14Hz, 3-position-CH2S-) 5.05 (d, 1H, J=5Hz, 6-position-H) .15 (s, 2H, dioxole-CH2~) .72 (d x d, 1H, J=5 and 9Hz, 7-position-H) 6.13 (s, 1H, -CH-CONH-) 7.4 (m, 5H, phenyl) 8.73 (br. 3H, ~NH3+) 9.46 (d, 1H> J=9Hz, -CONH-) Example 2 Synthesis of (5-methyl-l,3-dioxol-2-on-4-yl)methyl 7- [D-ot- (L-alanyloxy) -p-hydroxyphenylacetamido] -3- (5-methyl- 20864 1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate hydrochloride (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-a-(Boc-L-alanyloxy)-p-hydroxyphenylacetamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate (0.8 g) is dissolved in 3.9 ml of formic acid, followed by addition, at 0°C, of 1.26 ml of 4.08 N hydrogen chloride in isopropyl alcohol. After stirring at room temperature for 10 minutes, diethyl ether is added to the reaction mixture, and the resulting precipitate is collected by filtration, washed with diethyl ether and dried to give 586 mg of the title compound.

IR (nujol, cm"1) ; 1830, 1790, 1760, 1695 NMR ((CD3)2SO, 6 value) ; I 1.45 (d, 3H, J=7Hz, -CH-CH3) 2.18 (s, 3H, dioxole-CH^) 2.66 (s, 3H, thiadiazole-CH^) 3.64 (br. s, 2H, 2-position-H2) 4.08, 4.66 (d, d, J=14Hz, 3-position-CH2S-) i 4 a, 4.3 (m, 1H, -CH-CH3) .12 (d, 1H, J=5Hz, 6-position-H) .14 (s, 2H, dioxole-CHj-) .69 (d x d, 1H, J=5 and 9Hz, 7-position-H) i 6.0 (s, 1H/ -CH-CONH-) 6.78, 7.31 (d, d, 4H, J=8Hz, phenyl) 8.7 (br. 4H, -OH, ~NH3+) 9.3 (d, 1H, J=9Hz, -CONH-) 20864 Example 3 (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-{D-0-[N-(1-methyl-2-ethoxycarbonylvinyl)-L-alanyl}mandelamido]-3- (5-methyl-1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carbox-ylate is treated by the procedure of Example 1, Process (4) to give the same product as in Example 1.

Example 4 (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-0-(N-trityl-L-alanyl)mandelamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)-thiomethyl-3-cephem-4-carboxylate is treated by the procedure of Example 2 to give the same product as in Example 1.

Example 5 (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-0-(N-p-methoxybenzyloxycarbonyl-L-alanyl)mandelamido]-3-(5-methyl-1,3, 4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate is treated by the procedure of Example 1, Process (4) to give the same product as in Example 1.

Example 6 (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-0-(N-trimethylsilyl-L-alanyl)mandelamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate is treated by the procedure of Example 1, Process (3) to give the same product as in Example 1.

Example 7 (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-0-(N-benzyloxycarbonyl-L-alanyl)mandelamido]-3-(5-methyl-l,3,4- 2 086 4 9 thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate is debenzylated with acetic acid-hydrobromic acid. Ether is added to the reaction mixture and the hydrobromide obtained is converted to the free base. Conversion of the base to the hydrochloride give the same product as in Example 1.

Example 8 (5-Methyl-l, 3-dioxol-2-ori-4-yl) methyl 7- [D-0- (N-2,2,2-trichloroethoxycarbonyl-L-alanyl)mandelamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate is dissolved in 10 ml of acetic acid. Then, at 20°C, 2 g of active zinc is added and the mixture was stirred for an hour. Methylene chloride is added, and the insoluble matter is filtered off. The filtrate is washed quickly with cold aqueous sodium bicarbonate and cold aqueous sodium chloride and dried over anhydrous sodium sulfate, and then the solvent is distilled off under reduced pressure. To the residue is added 0.2 ml of 5 N methanolic hydrogen chloride solution, followed by addition of 1 ml of methanol and 10 ml of acetone, whereby the compound of Example 1 is obtained.

Reference Example 1 Production of D-O-(L-alanyl)mandelic acid chloride hydrochloride D-0-(L-alanyl)mandelic acid hydrochloride (7 g) is suspended in 140 ml of methylene chloride and, under cooling, 140 ml of an 8% solution of phosphorus pentachloride 208649 in methylene chloride is added. After stirring overnight, the solid matter is collected by filtration, washed with methylene chloride and dried to give 7.5 g (94% yield) of 2 8 the title compound. = "56.28° (c = 1, dioxane) IR (nujol, cm ^) ; 3020, 1790, 1750 NMR (CF3COOD, 6 value) ; I 1.83 (d, 3H, J=7Hz, -CH-CH3) I 4.65 (q, 1H, J=7Hz, -CH-CH-j) l 6.32 (s, 1H, -CH-CONH-) 7.51 (s, 5H, phenyl) Reference Example 2 Synthesis of D-0-(Boc-L-alanyl)mandelic acid Boc-L-alanine (2 g) is dissolved in 30 ml of anhydrous tetrahydrofuran. Following addition of 1.1 g of triethyl-amine, a solution of ethyl chloroformate in 10 ml of anhydrous tetrahydrofuran is added dropwise at -20°C. The mixture is then stirred at the same temperature for 30 minutes. To the mixture are added 1.61 g of mandelic acid and 50 mg of 4-dimethylaminopyridine, and the whole mixture is stirred at 0°C for 30 minutes and then at room temperature for 2 hours. The solvent is then distilled off under reduced pressure, ethyl acetate is added to dissolve the residue, the solution is washed with water and aqueous sodium chloride and dried over anhydrous sodium sulfate. Removal of the solvent by reduced pressure distillation, addition of hexane and allowing to stand gives 830 mg of the title compound (the same compound as 20864 the product of Example 2). (Yield 24%) IR (nujol, cm"1) ; 3500, 3425, fl725, 1690 NMR (CDC13, 6 value) ; 1.38 (s, 9H, -C(CH3)3) I 1.4 0 (d, 3H, J=7Hz, CH3-CH-) I 4.40 (m, 1H, CH3-CH-) 6.00 (s, 1H, <f>-CH-) 7.2 ^ 7.5 (m, 6H, <j>, -COOH) 9.27 (br. s, 1H, -NH-) Reference Example 3 49.7 g of D-0-(N-Boc-L-alanyl)mandelic acid obtained in Reference Example 2 and 62 g of (5-methyl-l,3-dioxol-2-on-4—yl)methyl 7-amino-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate are dissolved in 600 ml of methylene chloride. At -5°C, 80 ml of a 2 N solution of N,N'-dicyclohexylcarbodiimide in methylene chloride is added dropwise, followed by stirring at the same temperature for an hour. The insoluble matter is filtered off, the filtrate is evaporated under reduced pressure, ethyl acetate is added to the residue, the mixture is filtered, the filtrate is evaporated under reduced pressure, methanol is added to the residue, and the resulting crystalline precipitate is collected by filtration and dried to give 72 g of (5-methyl-l,3-dioxol-2-on-4-yl)-methyl 7-[D-0-(N-Boc-L-alanyl)mandelamido]-3-(5-methyl-1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate. Melting point: 156°C (decomposition). 208649 IR (nujol, cm"1) ; 3340, 1820, 1780, 1750, 1680 NMR (CDC13, 6 value) ; I 1.40 (d, 3H, J=7Hz, -CH-CH3) 1.41 (s, 9H, -C(CH3)3) 2.22 (s, 3H, dioxole-CH3) 2.73 (s, 3H, thiadiazole-CH3) 3.42, 3.82 (d, d, 2H, J=17Hz, 2-position-H2) 3.89, 4.91 (d, d, 2H, J=14Hz, 3-position-CH2S-) 4.1 ^ 4.55 (m, 1H, -CH-CH3) .0 (br. 1H, -NH-) .03 (d, 1H, J=5Hz, 6-position-H) .05 (s, 2H, dioxole-CH2-) .69 (d x d, 1H, J=5 and 9Hz, 7-position-H) 6.19 (s, 1H, -CH-CONH-) 7.4 (s, 5H, phenyl) 7.68 (d, 1H, J=9Hz, -CONH-) Reference Example 4 (5-Methyl-l,3-dioxol-2-on-4-yl)methyl 7-amino-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate (45.6 g) is dissolved in 500 ml of methylene chloride and, at 0°C, 17.8 g of anhydro-O-carboxymandelic acid is added over 15 minutes. Thereafter, stirring is continued at the same temperature for 2 hours. The solvent is distilled off under reduced pressure, the residue is dissolved in ethyl acetate, and the solution is washed with saturated aqueous sodium bicarbonate and saturated aqueous sodium chloride, dried over anhydrous sodium 2 086 4 9 sulfate and concentrated under reduced pressure. Isopropyl ether is added and the solid matter (precipitate) is collected by filtration and recrystallized from methanol to give 49 g of (5-methyl-l,3-dioxol-2-on-4-yl)methyl 7-D-mandelamido-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiGmethyl-3-cephem-4-carboxylate. Melting point: 151°C (decomposition) .

IR (nujol, cm"1) ; 3350, 1820, 1780, 1730, 1680 NMR ((CD3)2SO, 6 value) ; 2.22 (s, 3H, dioxole-CH^) 2.70 (s, 3H, thiadiazole-CH^) 3.59, 3.97 (d, d, 2H, J=17Hz, 2-position-H2) 4.07, 4.87 (d, d, 2H, J=14Hz, 3-position-H2) .12 (d, 1H, J=5Hz, 6-position-H) .15 (s, 2H, dioxole-CH2-) .21 (d, 1H, J=6Hz, -CH-OH) .41 (d, 1H, J=6Hz, -OH) .81 (d x d, 1H, J=5 and 9Hz, 7-position-H) 7.42 (m, 5H, phenyl) 7.99 (d, 1H, J=9Hz, -CONH-) Reference Example 5 (1) To 1.7 g of 7-[D-0-(L-alanyl)mandelamido]-3-(5-methyl-1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylic acid and 0.4 g of ethyl acetoacetate, there is added 20 ml of methanol, followed by addition of a solution of 0.2 g of potassium hydroxide in 15 ml of methanol with stirring at room temperature. After 4 hours of stirring, 350 ml of 2 086 diethyl ether is added to the reaction mixture, and the resulting solid precipitate is collected by filtration and dried to give 1.92 g of potassium 7-[D-0-{N-(1-methyl-2-ethoxycarbonylvinyl)-L-alanyl}mandelamido]-3-(5-methyl-1,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxyrate.

NMR ((CD3)2SO, 6 value) 1.15 (t, 3H, J=7Hz, -C02CH2CH3) 1.41 (d, 3H, J=7Hz, -CH-CH3) I — 1.92 (s, 3H, CH3-C=) 2.66 (s, 3H, thiadiazole-CH3) 3.4 (br. s, 2H, 2-position-H2) I 3.9 ^ 4.8 (m, 3H, 3-position-CH2S-, -CH-CH3) 3.98 (q, 2H, J=7Hz, -C02-CH2~CH3) I — 4.43 (s, 1H, —C=CH-) 4.94 (d, 1H, J=5Hz, 6-position-H) .50 (d x d, 1H, J=5 and 9Hz, 7-position-H) 6.01 (s, 1H, —(^H-CONH-) 7.36 (s, 5H, phenyl) 8.67 (d, 1H, J=9Hz, -CONH-) 9.25 (d, 1H, J=9Hz, -NH-) (2) A 1 g portion of the compound obtained above in (1) is dissolved in 20 ml of N,N-dimethylformamide, and a solution of 0.37 g of 4-bromomethyl-5-methyl-l,3-dioxol-2-one in 2 ml of N,N-dimethylformamide is added dropwise at -10°C, followed by stirring at the same temperature for 30 minutes. To the reaction mixture is added 100 ml of water, and the mixture is extracted with two 50-ml 20864 portions of ethyl acetate. The ethyl acetate layers are combined and washed with water and saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. Removal of the solvent under reduced pressure, addition of diethyl ether to the residue, collection'of the solid precipitate by filtration and drying of the same give 0.6 g of (5-methyl-l,3-dioxol-2-on-4-yl)methyl 7- [D-0-{N-(l-methyl-2-ethoxycarbonylvinyl)-L-alanyl} mandelamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate.

NMR ((CD3)2SO, 6 value) 1.16 (t, 3H, J=7Hz, -C02-CH2-CH3) I — 1.41 (d, 3H, J=7Hz, -CH-CH3) 1.92 (s, 3H, CH3-C=) 2.18 (s, 3H, dioxole-CH3) 2.65 (s, 3H, thiadiazole-CH3) 3.65 (br. s, 2H, 2-position-H2) 4.0 (q, 2H, J=7Hz, -C02CH2CH3) 4.0 ^ 4.8 (m, 3H, 3-position-CH2S-, -CH-CH3) 4.42 (s, 1H, -C=CH-) .10 (d, 1H, J=5Hz, 6-position-H) .13 (s, 2H, dioxole-CH2~) .72 (d x d, 1H, J=5 and 9Hz, 7-position-H) j .98 (s,- 1H, -CH-CONH-) 7.38 (s, 5H, phenyl) 8.70 (d, 1H, J=9Hz, -C0NH-) 9.35 (d, 1H, J=9Hz, -NH-) 2 086 4 9 Reference Example 6 Methylene chloride (30 ml) and 15 ml of ethyl acetate are added to 0.88 g of D-ot-(N-Boc-L-alanyloxy)-p-hydroxy-phenylacetic acid and 1 g of (5-methyl-l,3-dioxol-2-on-4-yl) methyl 7-amino-3- (5-methyl-l, 3,4-thiadiazol-2-yl )*thio-methyl-3-cephem-4-carboxylate. To the suspension, there is added with stirring at -5°C, 2.8 ml of 1 N N,N'-dicyclo-hexylcarbodiimide in methylene chloride, followed by stirring at the same temperature for 1 hour. The insoluble matter is filtered off, the filtrate is evaporated under reduced pressure, ethyl acetate is added to the residue, again the insoluble matter is filtered off, isopropyl ether .is added to the filtrate, and the solid precipitate is collected by filtration and dried to give 1.45 g of (5-methyl-l,3-dioxol-2-on-4-yl)methyl 7-[D-a-(N-Boc-L-alanyloxy)-p-hydroxyphenylacetamido]-3-(5-methyl-l,3,4-thiadiazol-2-yl)thiomethyl-3-cephem-4-carboxylate. NMR (CDC13, 6 value) ; 1.39 (s, 9H, -C(CH3)3) 1.40 (d, 3H, J=7Hz, -CH-CH3) 2.19 (s, 3H, dioxole-CH3) 2.70 (s, 3H, thiadiazole-CH3) 3.38, 3.80 (d, d, 2H, J=17Hz, 2-position-H2) 3.89, 4.90 (d, d, 2H, J=14Hz, 3-position-CH2S-) 4.0 ^4.4 (m, 1H, -CH-CH3) 4.95 (d, 1H, J=5Hz, 6-position-H) .05 ^ 5.25 (m, 3H, -NH-, dioxole-CH2-) 2086 .70 (d x d, 1H, J=5 and 9Hz, 7-position-H) I 6.06 (s, 1H, -CH-CONH-) 6.75, 7.23 (d, d, 4H, J=8Hz, phenyl) 7.25 (br. 1H, -OH) 7.75 (d, 1H, J=9Hz, -CONH-)

Claims (2)

1. WHAT WE CLAIM IS:-

   208649

   CLAIM

   1 A method of producing cephalosporin derivatives of the general formula

   R2—(/ CH-CONH ^ S

   0

   rr

   -N

   N N

   CH^-S"^ ^S CH

   ^ 0 2" 3

   C=0

   | COOCH —nrmrp CH,

   CH-NH 2 I I

   | 0 0

   CH Y

   J 0

   2

   wherein R is hydrogen or hydroxyl, which comprises reacting a compound of the general formula

   R2 ^CH-COOH

   0

   1

   C=0

   I

   CH-NH-

   I

   ch3
2. 2 ...

   wherein R is as defined above, or a reactive derivative thereof with a compound of the formula

   NH

   2 ~| f I N N

   J^~N^^CH--S CH?

   0 ^

   C00CH2 I | CH3

   0 0

   Y

   o

   - 30

   208649

   or subjecting a compound of the general formula

   >2—M ^V-CH-CONH 1 { S N — N

   O f—n>y^ch2-S^—^S^CH3

   I O

   c=0 i i x cooch2 -j j ch3

   CH-NH-R

   I 0 0

   CH3 Y

   0

   wherein R1 is formyl; t-butoxycarbonyl, l-methyl-2-methoxy-carbonylvinyl, l-methyl-2-ethoxycarbonylvinyl, benzyloxy-carbonyl, p-methoxybenzyloxycarbonyl, chloroacetyl, trityl,

   2

   silyl or 2,2r2-trichloroethoxycarbonyl and R is as defined above/ to an R"'' group elimination reaction.

   A method as claimed in claim 1 substantially as herein particularly described with reference to any one of the Examples.

   Cephalosporin derivatives when produced by the method of claim 1.

   Baldwin

   Attorneys for the Applicant