CH649297A5 - Cephalosporin compounds, their preparation and pharmaceutical compositions containing them - Google Patents

Description

The invention relates to cephalosporin compounds with valuable antibiotic properties.

The cephalosporin compounds in the following description are described with reference to "Cepham" according to J. Amer. Chem. Soc., 1962, 84,3400, the term "cephem" referring to the cepham base structure with a double bond.

The cephalosporin antibiotics are widely used in the treatment of diseases caused by pathogenic bacteria in humans and animals, and they are particularly useful in the treatment of diseases caused by bacteria resistant to other antibiotics such as penicillin compounds in the treatment of penicillin-sensitive patients. In many cases, it has been desired to use a cephalosporin antibiotic that has activity against both Gram-positive and Gram-negative organisms, and considerable research has been devoted to the development of

(IV)

ch20h coor '

different types of broad spectrum cephalosporin antibiotics.

For example, British Patent 1,399,086 describes a new class of cephalosporin antibiotics m containing a 7β- (a-etherified oxyimino) acylamido group, the oxyimino group being in the syn configuration. This class of antibiotic compounds is distinguished by a high antibacterial activity against a number of Gram-positive and Gram-negative organisms, while at the same time there is a particularly high stability for β-lactamases which are produced by different Gram-negative organisms .

The discovery of this class of compounds has prompted further research in the field to attempt to find compounds with improved properties, for example over certain classes of organisms, particularly Gram-negative organisms.

For example, British Patent 1,453,049,335 contains cephalosporin antibiotics with a 3-carbamoyloxymethyl group and a 7β-acylamido group of the formula

R'.C.CO.NH-

40

N

(A)

OR2

described, wherein R1 is a furyl, thienyl or phenyl-4s group and R2 is a Ci-4-alkyl group, a C3-C7-cycloalkyl group or a phenyl group, the compounds being syn isomers or as mixtures of syn and anti isomers are present with at least 90% of the syn isomer. These compounds have a high antibacterial activity against a wide range of Gram-positive and Gram-negative organisms and a particularly high stability for β-lactamases which are produced by various Gram-negative organisms.

In addition, the British patent 55 1 496 757 cephalosporin antibiotics with a 7β-acylamido group of the formula

R.C.CO.NH-

60

N

RA

I.

(B)

65

X). (CH2) mC (CH2) nCOOH

I.

RB

(where R is a thienyl or furyl group; RA and RB can vary within wide limits and for example

649297

may be Ci-4-alkyl groups or together with the carbon atom to which they are attached can form a C3-7-cycloalkylidene group and m and n are each 0 or 1 such that the sum of m and n is the number 0 or 1)), these compounds being syn isomers or mixtures of syn and anti isomers with at least 90% of the syn isomer. The 3-position of the cephalosporin molecule can be unsubstituted or it can have one of a variety of possible substituents. These compounds were found to have particularly good activity against Gram-negative organisms.

Other compounds of similar structure have been developed from these compounds in further attempts to find antibiotics with improved broadband antibiotic activity and / or high activity against Gram-negative organisms. Such developments included variations not only in the 7β-acylamido group in the above formulas, but also in the introduction of special groups in the 3-position of the cephalosporin molecule.

For example, Belgian Patent 852,427 describes cephalosporin antibiotic compounds which fall within the general scope of British Patent 1,399,086 and in which the group R in formula (B) above can be replaced by a variety of different organic groups, including of 2-aminothiazol-4-yl and the oxygen atom in the oxyimi-no group is linked to an aliphatic hydrocarbon group, which in turn can be substituted, for example by carboxy. In such compounds, the 3-position substituent is an acyloxymethyl group (e.g. carbamoyloxymethyl), hydroxymethyl, formyl or an optionally substituted heterocyclic thiomethyl group.

Furthermore, Belgian patent 836 813 describes cephalosporin compounds in which the group R in the above formula (B) can be replaced, for example, by 2-aminothiazol-4-yl and the oxyimino group is a hydroxyimino or blocked hydroxyimino group, for example a methoxyimino group . In such compounds, the 3-position of the cephalosporin molecule is substituted by a methyl group, which in turn can optionally be substituted by any of a large number of residues of the nucleophilic compounds described therein; 10 As an example of such a substituted methyl group, a carbamoyloxymethyl group is given, which in turn can be substituted by an alkyl group, for example a methyl group. No antibiotic activity is ascribed to such compounds in this patent, they are only mentioned as intermediates for the preparation of antibiotics described in this patent.

Belgian patent 853 545 describes cephalosporin antibiotics, the 7β-acylamido side chain 20 being primarily restricted to a 2- (2-aminothiazol-4-yl) -2- (syn) -met-hoxyiminoacetamido group and the substituent in 3-position is broadly defined in a manner similar to that in the aforementioned Belgian patent 836 813. Compounds that are specifically mentioned in the description include compounds in which the 3-position is substituted by a carbamoyloxymethyl radical.

It has now been found that through a suitable selection of a small number of special groups in the 7-position in combination with a carbamoyloxymethyl group 30 in the 3-position, cephalosporin compounds with particularly advantageous activity (which is described in more detail below) over a wide range of usually pathogenic organisms can be obtained.

The invention therefore relates to cephalosporin antibiotics of the general formula x *

s n

W-

h f j

«

c.co.nh j-

n ra 0 ^ - "n ch2 # o.cö.nh2

^ 0.c.cooh cooh

'b R

wherein Ra and Rb, which are identical or different from one another, each represent a C1-4-alkyl group, preferably a straight-chain alkyl group, for example methyl, ethyl, n-propyl or n-butyl and especially a methyl or ethyl group, or Ra and Rb together with the carbon atom to which they are attached form a C3-7-cycloalkylidene group, preferably a C3-s-cycloalkylidene group, the non-toxic salts and the non-toxic metabolically labile esters of these compounds, furthermore the non- toxic salts of the esters just mentioned as well as the solvates of the compounds of formula (I).

The compounds according to the invention are syn isomers.

The syn-isomeric form is defined by the configuration of the group

60 Ra

I.

-O.C.COOH

I.

Rb

65

with respect to the carboxamido group. In the present description, the syn configuration is structurally referred to as

5

649 297

s n c.co.nh

II

N aa

\ t o.c.cooh

It should be mentioned that, since the compounds according to the invention are geometric isomers, some mixing with the corresponding anti-isomer can occur.

The compounds according to the invention can exist in tautomeric forms (with respect to the 2-amino-thiazolyl group) and it should be mentioned that such tautomeric forms, for example the 2-aminothiazolinyl form, fall within the scope of the invention.

It should also be noted that if Ra and Rb in the above formulas represent different Ci-4-alkyl groups, the carbon atom to which they are attached includes an asymmetry center. Such compounds are diastereoisomeric and the invention encompasses the various diastereoisomers of these compounds as well as the mixtures thereof.

As already said, the invention also includes the solvates, in particular the hydrates of the compounds of the formula (I). It also includes the salts of the esters of the compounds of the formula (I) already mentioned.

The compounds according to the invention have good broadband antibiotic activity. The activity is unusually high towards Gram-negative organisms. This high activity extends to many β-lactamase-producing gram-negative strains. The compounds also have high stability to β-lactamases, which are produced by a number of Gram-negative organisms.

It has been found that the compounds according to the invention have an unusually high activity against strains of Pseudomonas, e.g. Strains of Pseudomonas aeruginosa, as well as high activity against various members of the Enterobacteriaceae (e.g. strains of Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, Enterobacter cloacae, Serratia marcescens, Providence species, Proteus mirabilis and in particular indole-positive and Proteus organisms such as Proteus organisms Proteus morganii) and strains of Haemophilus influenzae.

The non-toxic salts which can be formed by reaction of one or both of the carboxyl groups present in the compounds of general formula (I) include salts of inorganic bases such as alkali metal salts (e.g. sodium and potassium salts) and alkaline earth metal salts (e.g. calcium salts) ; Amino acid salts (e.g. lysine and arginine salts); Salts of organic bases (e.g. procaine, phenylethylbenzylamine, dibenzylethylenediamine, ethanolamine, diethanolamine and N-methylglucosamine salts). Other non-toxic salts include acid addition salts e.g. formed with hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, formic acid and trifluoroacetic acid. The salts may also be in the form of resinates formed with, for example, a polystyrene resin or cross-linked polystyrene-divinyl-benzene copolymer resin containing amino or quaternary amino groups or sulfonic acid groups or with a resin containing carboxyl groups e.g. a polyacrylic acid resin. Soluble base salts (e.g. alkali metal salts such as the sodium salt) of the compounds of the formula (I)

can be used in therapeutic applications because of the rapid distribution of these salts in the body after administration. However, if insoluble salts of the compounds of formula (I) are desired in a particular application e.g. for use in depot preparations, such salts can be formed in a conventional manner, for example with suitable organic amines.

These and other salts, such as the salts with toluene-p-sulfonic acid and methanesulfonic acid, can be used as intermediates in the preparation and / or purification of the compounds of the formula (I), for example in the processes described below.

Non-toxic metabolically labile esters which can be formed by esterification of one or both carboxyl groups in the parent compound of the formula (I),

include acyloxyalkyl esters, for example lower alkanoyloxymethyl or ethyl esters such as acetoxymethyl, acetoxyethyl or pivaloyloxymethyl ester.

Examples of preferred compounds according to the invention include the following compounds and their non-toxic salts and non-toxic metabolically labile esters, namely:

(6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (2-carboxyprop-2-oxyimino) acetamido] -3-carbamoyloxymethyl-ceph-3-em- 4-carboxylic acid and

(6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (l-carboxycy-clobut-1-oxyimino) acetamido] -3-carbamoyloxy methyl-ceph-3 -em-4-carboxylic acid.

Other compounds according to the invention include, for example, those in which the groups Ra and Rb in the formula (I) are as follows:

Ra Rb a) alkyl groups

-C2H5 -C2H5

-CH3 -C2H5

b) Cycloalkylidene groups, cyclopropylidene, cyclopentylidene, cyclohexylidene

The compounds of formula (I) can be used to treat a variety of diseases caused by pathogenic bacteria in humans and animals, such as infections of the respiratory tract and urinary tract.

According to the invention, a process for the preparation of an antibiotic compound of the general formula (I) as defined above or of its non-toxic salts or non-toxic metabolically labile esters is also provided, wherein

A) a compound of the formula s

10th

15

20th

25th

30th

35

40

45

50

55

60

65

649297

6

CH2.0oC0oNHR

(II)

coor-

where Rc is hydrogen or an N-protected group, e.g. a labile group such as an acyl group, especially a lower alkanoyl group such as acetyl, a halogen substituted lower alkanoyl group such as mono-, di- or trichloroacetyl, or a chlorosulfonyl or bromosulfonyl group, and R3 represents hydrogen or a carboxyl blocking group, e.g. the remainder of an ester-forming aliphatic or araliphatic alcohol or an ester-forming phenol, silanol or stannanol (this alcohol, phenol,

c.

11

N

COOH

Silanol or stannanol preferably contains 1 to 20 carbon atoms), or a salt, for example an acid addition salt (formed with, for example, a mineral acid such as

15 hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid or phosphoric acid or an organic acid such as methanesulfonic or toluene-p-sulfonic acid) or a base salt formed with a cation such as Na + or K +, or an N-silyl derivative thereof with an acid of the formula

20th

(iii)

O.C

R

* 4

coor

*

acylated, where Ra and Rb are as defined above, R4 represents a carboxyl blocking group, e.g. as described for R3 and R5 is an amino or protected amino-40

grappe, or with one of these corresponding acylating agents or

B) a compound of the formula (ï V)

RJ

A

s n w.

c.co.nh

II

n ra

\ 1 3a

0.c.c00rja t

Rb

(xv) ch.oh coor "

wherein Ra, Rb and R5 are as defined above and R3 and R3a independently represent hydrogen or a carboxyl blocking group, or a salt thereof is reacted with an acylating agent which forms a carbamoyloxymethyl- or N-protected carbamoyloxymethyl group in 3 position is suitable, whereupon any carboxyl-blocking and / or N-protecting groups which may be present are removed and, if appropriate, a carboxyl group is converted into a non-toxic salt or a non-toxic metabolically labile ester.

Acylating agents which can be used in the preparation of the compounds of formula (I) include acid halides, especially acid chlorides or bromides 60. Such acylating agents can be prepared by reacting an acid (III) or a salt thereof with a halogenating agent, for example phosphorus pentachloride, thionyl chloride or oxalyl chloride.

Acylation using acid halides 65 can conveniently be carried out in aqueous or non-aqueous reaction media at temperatures of from -50 ° to + 50 ° C, preferably at from -20 ° to + 30 ° C, if desired in the presence of an acid-binding agent.

Suitable reaction media include aqueous ketones such as aqueous acetone, esters such as ethyl acetate, halogenated hydrocarbons such as methylene chloride, amides such as dimethyl acetamide, nitriles such as acetonitrile, or mixtures of two or more such solvents. Suitable acid binding agents include tertiary amines (e.g. triethylamine or dimethylaniline), inorganic bases (e.g. calcium carbonate or sodium bicarbonate) and oxiranes such as low 1,2-alkylene oxides (e.g. ethylene oxide or propylene oxide) which bind the hydrogen halide released in the acylation reaction.

Acids of formula (III) can themselves be used as acylating agents in the preparation of the compounds of formula (I). If desired, the acylation using the acids (III) is carried out in the presence of a condensing agent, for example a carbodiimide such as N, N'-dicyclohexylcarbodiimide or N-ethyl-N'-y-dimethylaminopropylcarbodiimide; a carbonyl compound such as carbonyldiimidazole or an isoxazolium salt such as N-ethyl-5-phenylisoxazolium perchlorate.

The acylation can also be carried out with other amide-forming derivatives of acids of formula (III), for example an activated ester, a symmetrical anhydride or a mixed anhydride (e.g. formed with pivalic acid or with a halogen formic acid ester such as lower alkyl haloformate). Mixed anhydrides can also be formed with phosphoric acid (e.g. phosphoric or phosphorous acid), sulfuric acid or aliphatic or aromatic sulfonic acids (e.g. toluene-p-sulfonic acid). An activated ester can conveniently be formed in situ using, for example, 1-hydroxy-benzotriazole in the presence of a condensing agent as indicated above. Alternatively, the activated ester can be preformed.

The acylation reactions comprising the free acids or their amide-forming derivatives mentioned above are conveniently carried out in a non-aqueous reaction medium e.g. Methylene chloride, tetrahydrofuran, dimethylform amide or acetonitrile.

If desired, the above acylation reactions can be carried out in the presence of a catalyst such as 4-dimethylaminopyridine.

If desired, the acids of the formula (III) and the corresponding acylating agents can be prepared and used in the form of their acid addition salts. For example, the acid chlorides can expediently be used as hydrochlorides and the acid bromides as hydrobromides.

Carbamoylation of the 3-hydroxymethyl compounds of formula (IV) can be accomplished by conventional means using suitable carbamoylating agents, suitable carbamoylating agents comprising isocyanates of the formula Rd.NCO (wherein Rd is a labile substituent group) to form a compound containing a substituent in 3-position with the formula -CH20.C0NHRd (where Rd has the meaning given above). The labile group Rd can then be split off, for example by hydrolysis, to form a 3-carbamoyloxymethyl group. Examples of labile groups Rd which are easily cleavable after treatment include those labile groups as given above as examples for the group Rc and halogenated lower alkoxycarbonyl groups such as 2,2,2-trichloroethoxycarbonyl. Such labile groups can generally be split off by acid or base catalyzed hydrolysis (e.g. by base catalyzed hydrolysis using sodium bicarbonate).

The compounds of formula (IV) defined above,

649297

which are used as starting materials in process B) are new and represent a further subject of the invention as a means for carrying out process B). In addition to their usability as intermediates for the preparation of cephalosporin compounds with side chains in the 7-position of the same type as those of formula (II) above and having a variety of groups in the 3-position, the compounds also have useful antibiotic activity similar to that described above for the compounds of formula (II). These compounds can be obtained, for example, by enzymatic hydrolysis (e.g. using Rhodospiridium toruloides or Rhodotorula rubra) of a corresponding 3-acetoxymethyl compound e.g. the 3-acetoxy-methyl compound, for example, in an analogous manner to that described in British Patents 1,531,212 and 1,474,519.

Metabolically labile esters of the compounds of formula (I) can be prepared by reacting a compound of formula (I) or a salt thereof with a suitable esterifying agent such as an acyloxyalkyl halide (eg iodide), conveniently in an inert organic solvent such as dimethylformamide or acetone and then if necessary, by removing any protective groups.

The salts of the compounds of formula (I) with bases can be formed by reacting an acid of formula (I) with a suitable base. For example, the sodium or potassium salts can be prepared using the corresponding 2-ethylhexanoate or hydrogen carbonate. The acid addition salts can be prepared by reacting a compound of formula (I) or a metabolically labile ester thereof with a suitable acid.

When a compound of formula (I) is obtained as a mixture of isomers, the syn isomer can be obtained by, for example, conventional methods such as crystallization or chromatography.

For use as starting materials for the preparation of the compounds of the general formula (I) according to the invention, preference is given to compounds of the general formula (III) and corresponding acid halides and anhydrides in the syn-isomeric form or in the form of mixtures of the syn-isomeric and the corresponding anti-isomers containing at least 90% of the syn-isomer used.

The acids of formula (III) (provided that Ra and Rb together with the carbon atom to which they are attached do not form a cyclopropylidene group) can be prepared by etherifying a compound of the formula it n

^ OH

(wherein R5 is as defined above and R6 represents a carboxyl-blocking group) by reaction with a compound of the general formula

7

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

649297

R'1

I.

T.C.COOR4

I.

Rb

(VI)

(wherein Ra and Rb and R4 are as defined above and T is halogen such as chlorine, bromine or iodine, sulfate or sulfonate such as tosylate), and then by removing the carboxyl blocking group R6. The xo isomers can be separated either before or after such etherification. The etherification reaction is generally carried out in the presence of a base e.g. Potassium carbonate or sodium hydride and is preferably carried out in an organic solvent, for example dimethyl is sulfoxide, a cyclic ether such as tetrahydrofuran or dioxane or an N, N-disubstituted amide such as dimethylformamide. Under such conditions, the configuration of the oxyimine group is essentially unchanged by the etherification reaction. The reaction is said to be carried out in the presence of a base when an acid addition salt of a compound of formula (IV) is used. The base should be used in an amount sufficient to quickly neutralize the acid in question.

The acids of the general formula (III) can also be obtained by reacting a compound of the formula r5

uz.

25th

30th

co.coor

(vii)

35

(wherein R5 and R6 are as defined above) with a compound of the formula

Ra

H2N.O.C.COQR4

Rh

(VIII)

(wherein Ra, Rb and R4 are as defined above) and then removing the carboxyl blocking group R6 and, if necessary, by separating the syn and anti isomers.

The latter reaction is particularly applicable to the preparation of acids of formula (III) in which Ra and Rb s0 together with the carbon atom to which they are attached form a cyclopropylidene group. In this case the corresponding compounds of formula (VIII) can be prepared in a conventional manner, e.g. by the synthesis described in Belgian patent 866 422 for the preparation of t-butyl-1 - S5 amino-oxycyclopropanecarboxylate.

The acids of formula (III) can be converted into the corresponding acid halides and anhydrides and acid addition salts by conventional means, for example as described above. 60

It should be noted that in some of the above conversions, it may be necessary to protect any sensitive groups in the molecule of the compound in question in order to avoid undesirable side reactions. For example, during any of the 6S reaction sequences mentioned above, it may be necessary to protect the NH2 group of the aminothiazolyl portion by, for example, tritylation, acylation (e.g. chloroacetylation), protonization, or other appropriate method. The protecting group can then be removed in any suitable manner which does not cause degradation of the desired compound, e.g. in the case of a trityl group by using an optionally halogenated carboxylic acid e.g. Acetic acid, formic acid, chloroacetic acid or trifluoroacetic acid or use of a mineral acid e.g. Hydrochloric acid or mixtures of such acids, preferably in the presence of a protic solvent such as water or, in the case of a chloroacetyl group, by treatment with thiourea.

The carboxyl-blocking groups which are used in the preparation of the compounds of the formula (I) or in the preparation of the necessary starting materials are expediently groups which can expediently be split off easily in a suitable stage of the reaction sequence in the last stage. However, in some cases it may be appropriate to use non-toxic metabolically labile carboxyl blocking groups such as acyloxyalkyl groups (e.g. acetoxymethyl or ethyl or pivaloyloxymethyl) and to retain them in the final product in order to use a suitable ester of the compound of formula (I) to surrender.

Suitable carboxyl blocking groups are known and a list of representative blocked carboxyl groups is listed in British Patent 1,399,086. Preferred blocked carboxyl groups include aryl lower alkoxycarbonyl groups such as p-methoxybenzyloxycarbonyl, p-nitrobenzyloxycarbonyl and diphenylmethoxycarbonyl; lower alkocycarbonyl groups such as tert-butoxycarbonyl; lower haloalkoxycarbonyl groups such as 2,2,2-trichloroethoxycarbonyl. Carboxyl-blocking group or groups can then be removed by any suitable method known from the literature; for example, acid or base catalyzed hydrolysis can be used in many cases, such as enzymatically catalyzed hydrolysis.

The antibiotic compounds according to the invention can be formulated for administration in any suitable manner in analogy to other antibiotics and the invention also encompasses pharmaceutical compositions which contain an antibiotic compound according to the invention and are adapted for use in human therapy or veterinary medicine. Such compositions can be presented for use in a conventional manner by means of any necessary pharmaceutical carriers or excipients.

The antibiotic compounds according to the invention can be formulated for injection and can be presented in unit dose form in ampoules or in multiple dose containers, if necessary with an added preservative. The compositions can also have forms such as suspensions, solutions and emulsions in oily or aqueous media and can contain formulating agents such as suspending agents, stabilizing or dispersing agents. Alternatively, the active ingredient can also be in powder form for dissolution in a suitable medium, e.g. sterile pyrogen-free water, available before use.

If desired, such powder formulations may contain a suitable non-toxic base to improve the water solubility of the active ingredients and / or to ensure that when the powder is dissolved in water the pH of the resulting aqueous formulation is physiologically acceptable. Alternatively, the base can be present in the water used to prepare the powder for solution for injection. The base can, for example, be an inorganic base such as sodium car-

649297

bonate, sodium bicarbonate or sodium acetate or an organic base such as lysine or lysine acetate.

The antibiotic compounds can also be formulated as suppositories e.g. containing common supplement bases such as cocoa butter or other glycerides.

The compositions for veterinary medicine can be formulated, for example, as intramammary preparations either on a long-term basis or on a fast-acting basis.

The compositions can range from 0.1%, e.g. Contain 0.1 to 99% of active material depending on the method of administration. When the compositions comprise dosage units, each unit will preferably contain 50 to 1500 mg of the active ingredient. The dosage as used for an adult in human medicine will preferably be from 500 to 6000 mg per day depending on the route of administration and the frequency of administration. For example, in adults in human medicine, 1000 to 3000 mg per day administered intravenously or intramuscularly is usually sufficient.

Higher daily doses may be required to treat Pseudomonas infections.

The antibiotic compounds according to the invention can be used in combination with other therapeutic agents such as antibiotics, e.g. Penicillins or other cephalosporins can be administered.

The following examples illustrate the invention. All temperatures are in ° C. “Petrol” is supposed to mean petroleum ether with a boiling range of 40 to 60 ° C.

Manufacturing 1

Ethyl (Z) -2- (2-aminothiazol-4-yl) -2- (hydroxyimino) acetate

A solution of 180 g of sodium nitrite in 400 ml of water was added to a stirred, ice-cold solution of 292 g of ethyl acetate toacetate in 296 ml of glacial acetic acid in such a way that the reaction temperature was kept below 10 ° C. Stirring and cooling continued for about 30 minutes when a solution of 160 g calcium chloride in 800 ml water was added. The resulting mixture was stirred for 1 hour. The lower oily phase was separated and the aqueous phase was extracted with diethyl ether. The extract was combined with the oil, washed successively with water and saturated saline, dried and evaporated. The remaining oil, which solidified on standing, was dried over petroleum ether and in vacuo over potassium hydroxide and gave 309 g of ethyl (Z) -2- (hydroxyimino) -3-oxobutyrate.

A stirred and ice-cold solution of 150 g of ethyl (Z) -2- (hydroxyimino) -3-oxobutyrate in 400 ml of dichloromethane was treated dropwise with 140 g of sulfuryl chloride. The resulting solution was kept at room temperature for 3 days and then evaporated. The residue was dissolved in diethyl ether, washed with water until the washings were almost neutral, dried and evaporated. The remaining oil (177 g) was dissolved in 500 ml of ethanol and 77 ml of dimethylaniline and 42 g of thiourea were added with stirring. After 2 hours the product was collected by filtration, washed with ethanol and dried to give 73 g of the title compound; F = 188 ° C (dec.).

Manufacturing 2

Ethyl (Z) -2-hydroxyimino-2- (2-tritylaminothiazol-4-yl) acetate, hydrochloride

16.75 g of trityl chloride was added portionwise over 2 hours to a stirred and cooled to −30 ° C. solution of 12.91 g of the product of preparation 1 in 28 ml of dimethyl

formamide, which contained 8.4 ml of triethylamine. The mixture was allowed to warm to 15 ° C over 1 hour, stirred for a further 2 hours and then partitioned between 500 ml of water and 500 ml of ethyl acetate. The organic phase was separated, washed with 2 × 500 ml of water and then shaken with 500 ml of 1N HCl. The precipitate was collected, washed successively with 100 ml of water, 200 ml of ethyl acetate and 200 ml of ether and dried in vacuo to give the title compound as an io white solid (16.4 g), M = 184 to 186 ° C (dec.).

Manufacturing 3

Ethyl- (Z) -2- (2-butoxycarbonylprop-2-oxyimino) -2- (2-trityl-aminothiazol-4-yl) acetate is 34.6 g of potassium carbonate and 25.5 g of tert-butyl-2 -bromo-2-methyl propionate in 25 ml of dimethyl sulfoxide was added under nitrogen to a stirred solution of 49.4 g of the product of preparation 2 in 200 ml of dimethsulfoxide and the mixture was stirred at room temperature for 6 hours. The mixture was poured into 21 water, stirred for 10 minutes and filtered. The solid was washed with water and dissolved in 600 ml of ethyl acetate. The solution was washed successively with water, 2N hydrochloric acid, water and saturated brine, dried and evaporated. The residue was recrystallized from petroleum ether (boiling range 60 to 80 ° C) and gave 34 g of the title compound of F = 123.5 to 125 ° C.

Manufacturing 4

30 (Z) -2- (2-butoxycarbonylprop-2-oxyimino) -2- (2-tritylami-nothiazol-4-yl) acetic acid

2 g of the product of Preparation 3 was dissolved in 20 ml of methanol and 3.3 ml of 2N sodium hydroxide was added. The mixture was heated to reflux for 1.5 hours and then concentrated. The residue was taken up in a mixture of 50 ml of water, 7 ml of 2N hydrochloric acid and 50 ml of ethyl acetate. The organic phase was separated and the aqueous phase was extracted with ethyl acetate. The organic solutions were combined, washed successively with water and saturated hydrochloric acid, dried and evaporated. The residue was recrystallized from a mixture of carbon tetrachloride and petroleum ether and gave 1 g of the title compound of F = 152 ° to 156 ° C. (dec.).

45

Manufacturing 5

Ethyl- (Z) -2- (2-tritylaminothiazol-4-yl) -2- (1-t-butoxycar-bonylcyclobut-1-oxyimino) acetate so 55.8 g of the product of preparation 2 were made under nitrogen in 400 ml of dimethyl sulfoxide with 31.2 g of finely ground potassium carbonate stirred at room temperature. After 30 minutes, 29.2 g of tert-butyl-1-bromocyclobutane carboxylate were added. After 8 hours a further 31.2 g of potassium 55 µm carbonate were added. During the next 3 days even more potassium carbonate (6x16 g portions) was added and after 3 days a further 3.45 g of tert-butyl-1-bromo-cyclobutane carboxylate was added. After a total of 4 days, the mixture was poured into about 31 ice water and the 60 solid was collected by filtration and washed well with water and petroleum ether. The solid was dissolved in ethyl acetate and the solution was washed twice with brine, dried with magnesium sulfate and evaporated to a foam. This foam was dissolved in 65% ethyl acetate-petroleum ether (1: 2) and filtered through 500 g of silica gel. Evaporation gave 60 g of the title compound as foam Vmax (CHBd) 3400 (NH) and 1730 cm "1 (ester).

649 297

10th

Manufacturing 6

(Z) -2- (1-t-Butoxycarbonylcyclobut-1-oximino) -2- (2-trityl-aminothiazol-4-yl) acetic acid

A mixture of 3.2 g of the product of Preparation 5 and 1.65 g of potassium carbonate was refluxed in 180 ml of methanol and 20 ml of water for 9 hours and the mixture was cooled to room temperature. The mixture was concentrated and the residue was partitioned between ethyl acetate and water to which 12.2 ml of 2N HCl was added. The organic phase was separated and the aqueous phase extracted with ethyl acetate. The combined organic extracts were washed with saturated brine, dried and evaporated to give 2.3 g of the title compound Xmax (ethanol) 265 nm (E ^ 243).

example 1

a) Diphenylmethyl- (6R, 7R) -7 - [(Z) -2- (2-t-butoxycarbonyl-prop-2-oxyimino) -2- (2-tritylaminothiazol-4-yl) -acetamido] -3- carbamoyloxymethyl-ceph-3-em-4-carboxylate

A stirred solution of 2.86 g of the product of preparation 4 and 2.64 g of diphenylmethyl- (6R, 7R) -7-amino-3-carbamoyloxymethyl-ceph-3-em-4-carboxylate in 50 ml of dimethyl Formamide was cooled to 0 ° C. and 745 ml of 1-hydroxybenzotriazole were added, followed by 1.14 g of dicyclohexylcar-bodiimide. The mixture was warmed to room temperature and stirred overnight. The mixture was filtered and the white solid washed with a little ethyl acetate. The filtrate and the washings were diluted with 200 ml of water and extracted with ethyl acetate. The organic extracts were combined, washed successively with 2N hydrochloric acid, water, sodium bicarbonate solution, water and saturated saline, dried and evaporated. The residue was eluted through a column of silica with ethyl acetate. The appropriate fractions of the eluate were collected and concentrated to give 3.6 g of the title compound Àmax (ethanol) 237.5 nm (E '270), A.inf256 nm (Ej 207) [aß0 + 15 ° (c 1.0, DMSO).

b) (6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (2-carboxy-prop-2-oxyimino) acetamido] -3-carbamoyloxymethyl-ceph-3 -em-4-carboxylic acid

20 ml of trifluoroacetic acid was added to a solution of 3 g of the product from step a) in 20 ml of anisole at 0 ° C. The mixture was stirred at room temperature for 2Vt hours and concentrated. The residue was dissolved in ether and evaporated again. The residue was dissolved in ethyl acetate and extracted with saturated sodium bicarbonate solution. The pH of the aqueous extracts was adjusted to 6 and the solution was washed with ethyl acetate. The aqueous phase was acidified to pH 1.5 under ethyl acetate and extracted with ethyl acetate. The combined organic extracts were washed with water and saturated saline, dried and evaporated. The residue was dissolved in 40 ml of warm 75% formic acid and left to stand for 1 hour. The mixture was diluted with water and filtered. The filtrate was concentrated. The residue was taken up in water again, filtered and lyophilized to give 450 ml of the title compound, tanf (pH 6 buffer) 235 nm (Ej'ém 253), 257 nm (egg 224), 295 nm (egg 104), ( Nujol) 1540,

1670 cm-1 (CONH), 1680 cm-1 (OCONHz), 1720 cnr1 (CO2H), 1780 cm-1 (ß-lactam).

Example 2

a) Diphenylmethyl- (6R, 7R) -7 - [(Z) -2- (l-t-butoxycarbonyl-cyclobut-l-oxyimino) -2- (2-tritylaminothiazol-4-yl) -acet-amido] - 3-carbamoyloxymethyl-ceph-3-em-4-carboxylate

A stirred solution of the product of manufacture 6 and

0.88 g of diphenylmethyl- (6R, 7R) -7-amino-3-carbamoyloxy-methyl-ceph-3-em-4-carboxylate in 20 ml of dimethylformamide was cooled to 0 ° C with 0.3 g of 1-hydroxy -benzotrialzole and then 0.45 g of dicyclohexylcarbodiimide and the 5 product isolated, essentially according to the method of Example la and gave 1.6 g of the title compound A. max (ethanol) 240 nm (Ej 242),? Unr305 nm (E | 58), Vmax (CHBn) 1522.1688 cm-1 (CONH), 1685 cm-1 (OCÖNHz), 1730 cm- '(CO2R), 1790 cm-1 (ß-lactam).

10th

b) (6R, 7R) -7 - [(Z) -2- (aminothiazol-4-yl) -2- (1-carboxycy-clobut-1 -oxyimino) -acetamido] -3-carbamoyloxymethyl-ceph-3- em-4-carboxylic acid

8 ml of trifluoroacetic acid were added to a solution of 2.3 g of the product of step a) in 2 ml of anisole at 0 ° C. The mixture was treated and treated essentially as described in Example 1b) and gave 285 mg of the title compound An, ax (pH 6 buffer) 239.5 nm (E] 194), Alf 292.5 nm (Egg 129), [alo + 32.5 ° (c 1.0, DMSO).

20th

Example 3

a) t-Butyl- (6R, 7R) -3-acetoxymethyl-7 - [(Z) -2- (2-t-butoxy-carbonylprop-2-oxyimino) -2- (2-tritylaminothiazol-4-yl) -acet-

25 amido] -ceph-3-em-4-carboxylate

A stirred solution of 572 mg of the product of preparation 4 and 328 mg of t-butyl- (6R, 7R) -3-acetoxymethyl-7-aminoceph-3-em-4-carboxylate in 10 ml of dimethylformamide was cooled to 0 ° C. treated with 150 mg of 1-hydroxybenzotriazole 30 and then 225 mg of dicyclohexylcarbodiimide and the product isolated as described in Example 1a and gave 533 mg of the title compound. A portion was recrystallized from di-isopropyl ether and had a melting point of 103 to 113 ° C (dec.). [a0 + 8.5 ° (c 1.0, DMSO).

35

b) (6R, 7R) -3-acetoxymethyl-7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (2-carboxyprop-2-oxyimino) acetamido] -ceph-3- em-4-carboxylic acid

18 ml of trifluoroacetic acid were added to a solution of 2.4 g of 40 of the product of step a) in 18 ml of anisole at 0 ° C. The mixture was treated essentially as described in Example 1b) and gave 920 mg of the title compound, Xmax (pH 6 buffer) 236 nm (E ^ m 250), Xm255 nm (E ^ m235), 296 nm (Ej'L 103 ); [a] 2D ° + 20.0 ° (c 1.0, DMSO).

45

c) (6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (2-carboxy-prop-2-oxyimino) acetamido] -3-hydroxymethylceph-3- em-4-carboxylate, disodium salt

1 g of the product of stage b) was suspended in a mixture of 15 ml of 0.2 molar pH7 phosphate buffer and 5 ml of water. The pH was adjusted to 6.8 by adding dilute sodium hydroxide solution and the resulting solution was treated with 1.5 ml of a semi-frozen suspension of Rhodospiridium toruloides (CBS 349) and the mixture was stirred at 22 ° C for 3 days.

The mixture was filtered and the filtrate was freeze-dried to give 1.37 g of crude product as an amorphous solid.

60 A sample (0.66 g) of the above product in water was treated on a 33 cm x 2.5 cm column containing "Amberlite XAD-2" resin. The column was sequentially washed with water and then with 25% ethanol eluted in water and the appropriate fractions were collected and pooled and evaporated in vacuo to a small volume.

This solution was freeze-dried and gave 0.216 g of the title salt A. max (pH 61 buffer) 235 nm 275) with infections at 251 nm (egg? Cm 257) and 290 nm 130), Vmax

11

649 297

(Nujol) 1760 (β-lactam), 1660 and 1534 (CONH) and Pharmaceutical Examples 1590 cm-1 (CO2).

Example a) - Dry powder for injection

Example 4 Sterile (6R, 7R) -7 - [(Z) -2- (aminothiazol-4-yl) -2-

a) t-ButyI- (6R, 7R) -3-acetoxymethyl-7 - [(Z) -2- (lt-butoxy- 5 (2-carboxyprop-2-oxyimino) acetamido] -3-carbamoyloxy-carbonylcyclobut-1 -oxyimino) -2- (2-tritylaminothiazol-4-yl) - methylceph-3-em-4-carboxylic acid disodium salt in glass acetamido] -ceph-3-em-4-carboxylate vials such that each vial has a lot equiva-

A stirred solution of 24.2 g of the product containing 250 ml of the antibiotic acid. Take the lung 6 and 13.6 g of tert-butyl- (6R, 7R) -3-acetoxymethyl-7-ami filling aseptically under a protective layer of sterile stick

noceph-3-em-4-carboxylate in 300 ml dimethylformamide 10 substance. The vials are cooled to 0 ° C using 4.5 g of 1-hydroxybenzotriazole mo rubber washers or stoppers, which are sealed with aluminum.

nohydrate and then sealed with 6.4 g of dicyclohexylcarbodiimide seals, whereby one is treated and the product is essentially gas exchange or penetration of microorganisms as in Example

1 b) described, isolated and gave 12.8 g of the title is combined. The product is then ready for use from F = 113.5 to 116.5 ° (dec.). [a] o + 15.0 ° (c 1.0, is made by adding water just before administration

DMSO). Injections or another suitable sterile carrier is dissolved.

b) (6R, 7R) -3-acetoxymethyl-7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (l-carboxycyclobut-2-oxyimino) acetamido] -ceph-3- Example b) - Dry powder for injection em-4-carboxylic acid 20 formulation for vials

100 ml of trifluoroacetic acid was added to a mixture of (6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (l-carboxycy-

12.5 of the product of stage a) and 5 ml of anisole at 0 ° C. clobut-1-oxyimino) acetamido] -3-carbamoyloxymethyl-ceph-

given. The mixture was treated and treated essentially as described in 3-em-4-carboxylic acid 500 mg, game 1 b), and gave 4 g of the title compound. Lysine acetate 368 mg of bond IW (pH 6 buffer) 246 nm (E | 264) , Lnf 295 nm 25

(E | ä; "118), [aß0 + 27.3 ° (c 1.0, DMSO). method

The sterile cephalosporin antibiotic is mixed with c) (6R, 7R) -7 - [(Z) -2- (aminothiazol-4-yl) -2- (l-carboxycy- sterile lysine acetate under aseptic conditions. It becomes clobut-1 - oxyimino) -acetamido] -3-hydroxymethylceph-3-em aseptically filled in glass vials under a protective layer of 4-carboxylic acid, sodium salt 30 sterile nitrogen. The vials are under

1 g of the product of stage b) was mixed in 15 ml of 0.2 molar pH using rubber washers or stoppers

7-buffer and 15 ml of water and suspended with a padlock, which is fixed by aluminum seals sion of Rhodospiridium toruloides (CBS 349) as they are in, causing a gas exchange or penetration of

Example 3 c) is described, treated and gave 0.756 g of the microorganisms is prevented. The product is made by

Title compound [cc] d + 78.8 ° (c 1.00, DMSO), Amax (pH 35 dissolving in water for injections or another

6 buffer), 246 nm (E) ^ m 311) with an inflection at 294.5 nm suitable sterile carrier shortly before the administration

(Ej'c ° m 124). ready to use.

B

Claims (12)

649297 2nd PATENT CLAIMS I. Cephalosporin antibiotics of the general formula: a2 s n w_ c. co. nh II n \ (I) ch2.o.co.nh2 cooh in which R "and Rb, which are identical or different from one another, each represent a Ci-4-alkyl group or Ra and Rb 20 together with the carbon atom to which they are attached form a C3-7-cycloalkylidene group, their non-toxic salts, their non-toxic metabolically labile esters and the non-toxic salts of these esters as well as the solvates of the compounds of formula (I) 2. (6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (2-carboxy-prop-2-oxyimino) acetamido] -3-carbamoyloxymethylceph-3- em-4-carboxylic acid and its non-toxic salts as compounds according to claim 1. 3. (6R, 7R) -7 - [(Z) -2- (2-aminothiazol-4-yl) -2- (l-carboxy-cyclobut-1-oxyimino) acetamido] -3-carbamoyloxymethyl-ceph-3 -em-4-carboxylic acid and its non-toxic salts as compounds according to claim 1. 4. A process for the preparation of an antibiotic compound of the general formula (I) according to claim 1 or of non-toxic salts thereof, characterized in that a compound of the formula h h coor ' ch2o.co.nhr (ii) wherein Rc is hydrogen or an N-protecting group and R3 is hydrogen or a carboxyl-blocking group, or a salt or N-silyl derivative thereof with an acid of formula u _c. cooh "v, a n h \ 1 4 0. c. coor ! b (in) wherein Ra and Rb are as defined in claim 1, R4 is a carboxyl-blocking group and R5 is an amino or protected amino group, or acylated with a corresponding acylating agent, whereupon any carboxyl-blocking and / or N-protecting groups present are removed and optionally converting a carboxyl group to a non-toxic salt. 5. Process for the preparation of an antibiotic compound of the general formula (I) according to claim 1 or of non-toxic salts thereof, characterized in that a compound of the formula: 3rd 649 297 h h 1 i c co nh « n \ r «.Ia 0. c. coor Rb wherein Ra, Rb and R5 are as defined above and R3 and R3a independently represent hydrogen or a carboxyl-blocking group, or react a salt thereof with an acylating agent which serves to carbamoyloxymethyl- or N-protected carbamoyloxymethyl- to form a group in the 3-position, whereupon any carboxyl-blocking and / or N-protecting groups present are removed and, if appropriate, a carboxyl group is converted into a non-toxic salt. 6. A process for the preparation of non-toxic, metabolically labile esters of an antibiotic compound of the general formula I according to claim 1, characterized in that said antibiotic compound is prepared by the process according to claim 4 and this or a salt thereof with an ester residue mentioned above corresponding esterifying agent. 7. A process for the preparation of non-toxic metabolically labile esters of an antibiotic compound of the general formula I according to claim 1, characterized in that said antibiotic compound is prepared by the process according to claim 5 and this or a salt thereof with an ester residue mentioned above corresponding esterifying agent. 8. A pharmaceutical composition for use in human or veterinary medicine, comprising an antibiotic compound according to one of claims 1 to 3 together with a pharmaceutical carrier or excipient. 9. Compounds of formula (IV) as means for carrying out the method according to claim 5.