DE2244915A1 - ANTIBIOTICS AND METHOD OF MANUFACTURING THEREOF - Google Patents

Description

DR. KAriL (LEORC LOSC

ί OO. . '.'. ¹ NCHENIS CiAJ; ΜΛ "ι <A-- it. I; I ¹ SbTFAiH 7βΟ, (

Munich, September 13, 1972 M / 12 262

BRISTOL-MYERS COMPANY
345, Park Avenue, New York, NY, USA

Antibiotics and processes for their manufacture

The present invention relates to a new antibacterial compound and a process for the preparation thereof. The present In particular, the invention relates to the preparation of the methoxymethyl esters of ampicillin and hetacillin, which themselves are valuable antibiotic drugs. It also includes' the present invention uses these: s hetacillin esters as an intermediate in the synthesis of other known ones Antibiotics.

309812/1258

The antibiotic compound of the present invention is a hetacillin derivative.

Hetacillin is a perficillin derivative that comes in the acid form
known as 6- (2,2-dimethyl-5-oxo-4-phenyl-1-imidazolidinyl) penicillanic acid. This compound, namely hetacillin,
j and many closely related compounds and how to make them
j are described in U.S. Patent 3,198,804. Ester
I of benzyl penicillins are in the British patent
j 1 003 479 and in U.S. Patent 2,650,218

j ■. ■:

j and acyloxymethyl ester of ampicillin are sold by W.V. Daehne j i et al. discussed in J. Med. Chem. 13, (4) 607-612 (1970). | ! This publication also makes reference to earlier publications I on the hydrolysis of esters. The pivaloyloxymethyl ester from! Ampicillin is in South African patent 68/5952

i I

I described. Various penicillin esters are also in the '. \ US Patent 3,528,965 described.

j t

ι ■ -.

; The compounds according to the invention have the following structure,

! _x / \ / ^H 3!

IR ¹ - CH - CH C.

i ill

! C N C - COOCH2OCH3

i ii

j 0

i Formula I.

in'

j where R is the group

NH ₂ ^(III)

or the group
means. -Z-

309812/1258

In general, the methoxymethyl ester of hetacillin ' by. Reacting hetacillin with a suitable esterifying agent;

Derivatives of the> methyl ether, such as halomethyl methyl ether, are produced. The hetacillin ester can also be obtained from a basic penicillin produced by fermentation, such as phenoxymethyl- ' ^! penicillin are produced by a series of ^reactions: where 'the Phenoxymethylpenicillinester by known encryption' is deacylated drive ■, with the corresponding methoxy \ methylester yields of 6-aminopenicillanic acid. The 6-amino penicillanic acid ester and a suitable acylating agent ^: can then be reacted as shown below. ί

The 6-Aminopenicillansäureester can be acylated in a known manner '\, where results in accordance with the choice of different acylating Penicillinester. | The choice of the acylating agent and the acylation conditions are not critical within narrow limits. Either the; free acid or the equivalent thereof can be used; to acylate the free amino groups of the 6-aminopenicillanic acid ester. Such acylating agents include the free acid and the corresponding carboxylic acid halides, for example _:. v / else the chlorides and bromides, the acid anhydrides including mixed anhydrides and especially the mixed anhydrides made from stronger acids such as lower aliphatic monoesters of carbonic acid, alkyl and aryl sulfonic acid and from more sterically hindered acids such as diphenylacetic acid. · In addition, an acid azide or an active ester or thioester (for example with p-nitrophenol, '2,4-dinitrophenol, thiophenol, thioacetic acid) can be used or the free acid itself can be mixed with 6-amino ^! penicillanic acid are coupled after this free acid has first ^{reacted with N, N 1} -Dimethylchlorformiminiumchlorid [British patent specification 1 008 170 and Novak and \ Weichet, Experientia XXI / 6, 360 (1965)] or one uses \

- 3 3098 12/1258

ι enzymes or a Ν, Ν'-carbonyldiimidazole or a Ν, Ν'-carbonylditriazole [South African patent 63/2 684] or a Carbodiimide reagent [especially NjN-dicyclohexylcarbodiimide, Ν, Ν'-diisopropylcarbodiimide or N-cyclohexyl-N '- (2-morpholinoethyl) -carbodiimide, Sheehan and Hess, J. Amer. Chem. Soc. 77, 1067 (1955)] or an alkynylamine peagent [R. Buijle and Η »G. Viehe, Angew. Chem. International Edition, 3> 582 (1964)] or a ketenimine reagent (CL. Stevens and M.E. Monk, J. Amer. Chem. Soc. 80, 4065 (1958)) or an isoxazolium salt reagent [R.B. Woodward, R.A. Olofson and H. Mayer, J. Amer. Chem. Soc. 83, 1010 (1961)]. Another equivalent of the acid chloride is a corresponding azolide, viz an amide of the corresponding acid whose amide nitrogen is a member of a quasi-aromatic five-membered ring, which contains at least two nitrogen atoms, namely imidazole, pyrazole, the triazoles, benzimidazole, benzotriazole and their substituted derivatives. An example of a general process for the preparation of an azolide is Ν, Ν'-carbonyldiimidazole . with a carboxylic acid in equimolar amounts at room temperature in tetrahydrofuran, chloroform, dimethylformamide or a similar inert solvent reacted, wherein the carboxylic acid imidazolide in practically quantitative Yield with release of carbon dioxide and 1 mole of imidazole. Dicarboxylic acids, give diimidazolides. The by-product, Imidazole, precipitates and can be separated and the imidazolide isolated, but this is not essential. The proceedings to carry out these reactions to make a penicillin and the methods used to make the Isolating penicillin produced in this way is known from the prior art (USA patents 3,079,314, 3,117,126 and 3,129,224 and British patents 932,644, 957,570 and 959,054).

30981? / 1 ? 5 8

When the acylating agent contains a free amino group it may be desirable to protect them with a suitable blocking agent. Such protecting groups include

! of the general formula ROCO- wherein R is an allyl, benzyl, subst. Benzyl, phenyl, subst. Phenyl or trityl group

ι means. Phenylglycylchloride hydrochloride is usually preferred chloride as an acylating agent. · '.,' V

j The resulting penicillin ester, namely the methoxymethyl ester of ampicillin can be reacted with acetone, which is the same as in US Pat. No. 3,198,804 described process of the hetacillin ester forms. '

Thus, the present invention includes a process for .Preparation of a compound of formula (I)

CH C

I ι ■ · - ..

C -. N - ■ C - COOCHgOCH ₃ H

wherein R is the group of the 'formula (II)

'y

or the group of the formula (III)

¹ ο "■

I!

CH-C-KH

NH ₂

means, characterized in that _t that 6-Aminopenicillansäuremethoxymethylester of formula (IV)

S CH _Q / \ / ~>

^KH 2 ^{CH C} ^ <, _H

Λ . I 3

_{0 = N c} _ COOCH2OCH3

acylated with the methoxymethyl ester of ampicillin and optionally this ampicillin ester with acetone converts, whereby the methoxymethyl ester of hetacillin forms.

An embodiment of the method according to the invention comprises the esterification of a penicillin of the structure

- Ci "- CH C ο π-3

CCOOK ""

Μ / 12262 _γ 224491

where R is an organic radical - many of which are on
known in the field of penicillins. The acyl group
any of the known penicillins can be used. One
a particularly suitable side chain is the phenoxymethyl group,

■■ s >

Examples of organic radicals are., Benzyl, furylmethyl, thienyl- J methyl., isoxazolyl and the like. It is well known that the 'j be substituted for various organic residues.

• I

Further specific examples of radicals containing aliphatic, carbocyclic and heterocyclic groups which represent the group R in the penicillin ^{starting materials:} are vinyl, ethoxy, cyclopentyl, cyclohexyl, 2,4-dichlorobenzyl, 3,4- Chlorobenzyl, m-bromobenzyl, o-bromobenzyl, j p-bromobenzyl, m-chlorobenzyl, o-chlorobenzyl, p-chlorobenzyl, | mrfluorobenzyl, o-fluorobenzyl, p-fluorobenzyl, p -Iodobenzyl-, \ p-Ni tr ob enzyl-, p-chlorophenoxymethyl-, in-nitrobenzyl-, o-nitrobenzyl-, 3-chloro-4-bromobenzyl-, m-trifluoromethylbenzyl, m-trifluoromethylphenoxymethyl-, p -Tolylmethyl, o-methylbenzyl, m-methylbenzyl-, 'phenylmercaptobenzyl-, p-methylmercaptobenzyl-, o-methoxybenzyl-, m-14ethoxybenzyl-, o-methylphenoxymethyl-, p-methoxy-: phenoxy: methyl, p-cyanobenzyl-, styryl, 3,4-dimethylbenzyl, '! 3-phenyl-bu-cyryl-, p-.beta.-naphthylmethyl Carbathoxyhydroxybenzyl- _3-f, ß-Naphthoxyme-thyl-, l-BrOEi-2-naphthylmethyl, 6-bromo -2-naphthyl- i methyl, 2-chloro-3-naphthylmethyl, 6-fluoro -2-naphthylniethyl-,
l-nitro-2-naphthylmethyl-, ß-kaphthylmercaptomethyl-, 6-meth-; oxy-2-naphthy, methyl, p-phenoxybenzyl, p-3iphenylylmethyl,
p-isopropylbenzyl and p-benzyloxybenzyl radicals.

3 0 9 8 19/1? R 8

Specifically, in the process of this invention a salt of the Phenoxymethy may! Be penicillins reacted in a suitable reaction medium with chloromethyl methyl ether at a temperature between about O ⁰ C and 50 ⁰ C and preferably between ⁰ ° C and about 3O ⁰ C. A preferred reaction medium is methylene chloride to which some dimethylformamide can be added, usually in a ratio of about "1 to 2 ml per 150 ml of methylene chloride. Dimethylformamide can also be used as the reaction medium. The reaction product can be recovered by conventional methods. J

The ester of phenoxymethylpenicillin obtained can then be deacylated either enzymatically or chemically. ι Enzymatic production of 6-aminopenicillanic acid is in

ι the USA patent specification 3,014,846 described. The preferred one

j The chemical cleavage process is carried out by

^! one imino halide by reaction with a halogen | ierungsmittel, such as phosphorus pentachloride, forms. The ester is dissolved in a non-aqueous solvent such as methylene chloride, benzene or chloroform to which a suitable amount of an acid binding agent such as dimethylaniline, pyridine, quinoline or lutidine has been added. The amount of acid-binding agent should be sufficient to absorb the acid formed by the reaction. The chlorination reaction temperature should be kept between about ~ $ 0 ° C to about 0 ⁰ C! to achieve a complete chlorination of the ester. ] The imino chloride is then treated with an alcohol under acidic conditions, an imino ether being formed under anhydrous conditions. Then water is added to the reaction mixture to hydrolyze the ether. The iminoether can be readily formed at temperatures of about -70 ⁰ C to about -30 ⁰ C.

309812/1258

• «J. ■

The general procedure for this sequence of reactions is described in U.S. Patent 3,499,909 along with various halogenating agents, \. acid-binding agents, alcohols and solvents, all of which can be ^{used 1 in general for the methoxymethyl esters according to the invention}

Alternatively, the 6-aminopenicillanic acid ester can be obtained directly from ' . ', 6-aminopenicillanic acid can be prepared by a process in which 6-aminopenicillanic acid is slurried in methylene chloride at about 25 ° C. and dissolved therein as the triethylamine salt. The reaction mixture is then ^{cooled to about 0} ° C. and esterified with chloromethyl methyl ether 6-aminopenicillanic acid ester can be isolated from the reaction mixture in the form of the free base or as an acid addition salt. The p-toluenesulfonate salt of the 6-aminopenicillanic acid ester is described in the literature by Jackson et. Al. Chemical Communications, 14, 1970. _r ^: ·. ';; -.

The acylation of the ö-aminopenicillanic acid esteri-s-ti-r production of the methoxymethyl ester of ampicillin can according to known Methods such as those in US Patents -2,985,648 and 3 140 282 described.

The above-mentioned toluene sulphate salt of 6-aminopenicillanic acid ester can be brought into contact with an acylating agent such as 2-phenylglycyl chloride hydrochloride in an acidic aqueous medium at low temperature. It _'is: .. the acylating agent in amounts of about 1 to 3 moles per mole of 6-aminopenicillanic acid used and the temperatures should be between about -10 ⁰ C and +20 ⁰ C. The pH of the reaction medium should be below 4 and preferably from about. 1.5 to about 3.0, usually between 2.0 and 2.8 The reaction medium is preferably a mixture of water and organic

309812/1258

/ D

! Solvents such as acetone, methylene chloride, or Tetrahydroj furan. The acylated ester can be obtained by increasing the pH

of the reaction medium to about 4 or higher, for example!

between 4 and 7, can be won. Any solids can

removed by filtration, a solution;

of the ampicillin ester results. I.

/ ί

According to a preferred method, the ester is in an i

Mixture of methylene chloride / acetone at ice bath temperatures,;

generally between about O ⁰ C 5 ⁰ C..und dissolved. A small ! Amount of water, about 2.5 % based on the volume of the organic solvent, is then added. The resulting

The mixture is kept at about O ⁰ C until the acid chloride '

has solved. The reaction product can then be prepared using standard i procedure can be obtained. This reaction can be carried out under anhydrous conditions.

The ampicillin methoxymethyl ester can be used in a reaction with: aqueous acetone at a pH of about 6.5 to. about 9.5. _; j can be converted into the corresponding hetacillin ester. In general, this stage of the process can be carried out at one temperature
between about -1O ⁰ C and 15 ⁰ C, although one
temperatures of about ⁰ ° C. to about 5 ^° C. are usually preferred
used. The pH and temperature should be during a
Sufficient time to maintain a. _; substantial conversion to hetacillin, for example during
about -12 to 170 hours depending on the other conditions to give j. After the reaction time of the Hetacillinmethoxy- can: be obtained methylester by the pH of the reaction \ to mix with an acid such as hydrochloric acid, between sets \ 1.5 and 2.0 and extracted with a suitable solvent] as methylene chloride. The hetacillin ester is made from
the organic phase obtained in the usual way.

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309812/1258

■ The hetacillin ester can easily be converted into hetacillin by hydrolysis of the ester group under acidic or mildly alkaline conditions. The ester can be in hydrochloric acid with a strength of 1 Ms 6-normal at temperatures between about O ⁰ C ^; and 40 ⁰ C are hydrolyzed. In concentrated hydrochloric acid, the product is recovered as a hydrochloride salt which can easily be redissolved and then reprecipitated in a suitable solvent such as water or a mixture of water and an organic liquid such as acetone or methyl isobutyl ketone, by adjusting the pH to sets the isoelectric point for hetacillin in the form of the free acid, namely about 2.5. The precipitation of the hydrochloride salt can be assisted by using a suitable soluble substance, such as ammonium chloride.

The a-carbon atom of the acyl side chain is an asymmetric one Carbon atom and the compounds according to the invention can therefore be both in optically active isomers. Forms as well as in ■ racemic form, which is a mixture of the two-optically active Represents forms, are present. All of these optical isomers and mixtures thereof are included within the scope of the present invention Invention.

The following examples are intended to illustrate the invention in more detail. however, do not limit them.

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262 22U915

example 1 Methoxymethyl ester of penicillin V

38.8 g Kaliumphenoxymethylpenieillinat are slurried in 150 ml of methylene chloride, and-the 'mixture is cooled to about 5 ⁰ C by means of eines.Kühlbades and 9.5 g (0.118 mol) of chloromethyl methyl ether and 0.5 ml of dimethylformamide are added. The cooling bath is removed and the mixture is stirred for about 1.5 hours while allowing the mixture to come to room temperature. The methylene chloride solution is washed four times with 200 ml portions of water and then dried and stripped to give 33.5 g of a yellowish oil. The yield is about 84 %.

example

6- Aminopenicillan acid methoxymethyl ester

<——— ** m — m - * - I! - ■■ - ■■■■■■■■ «•• ■■■■■■ WMIBmMMBMamilVMBMMMnMMMMM ^ ABM ^ IMMMMlMfc« III ■ I

Penicillin-V-methoxymethyl ester in 100 ml of methylene chloride cooled to -55 ⁰ C to a solution of 12 g (0.0304 moles) is j 4.8 ml (4.6 g, 0.038 mole) and then immediately dimethylaniline 7.0 g (0.0337 mol) of phosphorus pentachloride dissolved in 100 ml of methylene chloride. The mixture is kept at -4O ⁰ C to -5O ⁰ C for about 2 hours. Thin layer chromatography shows complete chlorination of the penicillin V ester. The J mixture is then cooled to -70 ⁰ C and 47 ml of methanol, j precooled to -50 ⁰ C are added rapidly. Then, the mixture is kept for 2 hours at -50 ⁰ C to -4o C ^0. To the resulting yellow solution, 100 ml of water are added with vigorous stirring. The temperature of the reaction mixture rises to about ⁰ ° C. and the pH of the mixture is about 0.6 to 1.0. After the mixture has been heated for about 10 to 15 minutes at this

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temperature and left in this pH range, the pH is brought to 6.5 to 6.8 with dilute sodium hydroxide. The layers are separated and the methylene chloride layer is washed with water, treated with activated charcoal and dried. Thin-layer chromatography shows methylaniline, methylphenoxyacetate and 6-aminopenicilanic acid methoxymethyl esteri. - "'- ■■■ -. - ■''"

Example 3
Methoxvmethvl-a ^ aminobenzvlpeniclllinat

A methyl chloride solution, the methoxymethyl ester of. 6-aminopenicillanic acid, prepared from 0.04 mol of methoxymethylphenoxymethylpenicillinate as in Example 2, is diluted with 100 ml of acetone. After cooling the resulting mixture to about. O ⁰ C to 5 ⁰ C is adding to the solution 5 ml of water and 0.04 mole (4.8 g) Dirnethylanilin. 8 g (0.039 mol) of phenylglycyl chloride hydrochloride are then added to the solution with vigorous stirring. "The mixture is ^{stirred for about 1 hour at 0} ° C., at which time all of the acid chloride is dissolved. The yield of methoxymethyl ester of α-aminobenzylpenicillin is 42 %. , determined by bioassay of the reaction product mixture. ·. j

Example 4 Methoxymethyl ester of hetacillin

An acylation reaction as described in Example 3 is described carried out using 13.0 g (0.05 mol) of 6-aminopenicillanic acid ester and 20.6 g (0.10 mol) of phenyl glycyl chloride

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hydrochloride. After any undissolved phenylglycyl chloride hydrochloride has been filtered off, the pH of the solution is adjusted to 8.5 with 10% sodium hydroxide and the mixture is left to age ^{at 8 ° C. for about 90 hours.} * Biotest gives a yield of about 60 %. The pH of the aged mixture is then adjusted to 1.8 with 6 η hydrochloric acid and the mixture is extracted with methylene chloride. The methylene chloride layer is washed with water, dried and stripped to give about 14.4 g of product.

example

Hetacillin ,

(a) 5 g of methoxymethyl ester of hetacillin are slurried in 50 ml of 3 η hydrochloric acid at 25 ° C. for about 20 minutes with vigorous stirring. The mixture is by means of a water bath to about ⁰ ° C to 5 ⁰ C gekühlt.und the pH is adjusted with 20% sodium hydroxide to 3.1. After crystallization, the solid is separated off by filtration and washed with acetone. The yield is 2.05 g of hetacillin with an activity of 913 γ / mg.

(b) 1 g of hetacillin methoxymethyl ester is added to 20 ml .6 η HCl, stirred for 2 minutes, seeded with hetacillin hydrochloride crystals and cooled to 0 ° C to 5 ° C. After about 10 minutes of further crystallization, the hetacillin hydrochloride is filtered off. The yield is 64 % of material with spectral (IR and NMR) and thin layer chromatography properties comparable to those of hetacillin hydrochloride.

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Example 6 Hetacillin methoxymethyl ester

To 38.9 g (0.1 mole) of hetacillin in 200 ^ mL of dry methylene chloride at 25 ⁰ C is added 10.1 g (0.1 mol) of triethylamine. The clear solution is cooled to ⁰ ° C. and 8.05 g (8 ml, 0.1 mol) of chloromethyl methyl ether, dissolved in 50 ml of methylene chloride, are added over a period of 10 minutes. After stirring at 0 ^° C. for 1 hour, the reaction mixture is filtered and concentrated under reduced pressure to an oil, which is taken up in acetone, filtered and concentrated again to give an oil. This oil is taken up in methylene chloride and with. Water with pH 2 and then washed twice with water with pH 7. After drying, the methylene chloride is removed in vacuo, giving an amorphous foamy solid. The yield is 40 g or 93 %. This material proves to be homogeneous on thin layer ■ chromatography and the IR and NMR spectra are in agreement with the structure of the desired product.

A sample of 2.0 g (4.6 mmol) is dissolved in 25 ml of acetone and 0.75 g (6.3 mmol) of p-toluenesulfonic acid monohydrate are added to the solution. After adding 25 ml of diethyl ether, crystallization begins. After 15 minutes at ⁰ ° C., the white crystals are filtered off, washed with ether and dried, giving 1.9 g of the toluenesulfonate salt of hetacillin: methoxymethyl ester.

Analysis C ^ gH ^ cN ^ SpOg

j calculated: found:

- 15 -

C. , 45 H , 82 N 92 55 , 75 5 , 12 ■ 6, 92 55 6th 6,

30 98 17/126 8

In a similar method of preparation, 20 g (0.046 mol) of hetacillin ester in 70 ml of tetrahydrofuran and 3 ml of conc. Hydrochloric acid was stirred ^{at 25 °} C. for 20 minutes and then at ⁰ ° C. to 5 ^{° C. for 30 minutes.} The resulting white precipitate is filtered off and washed with 100 ml portions of acetone. 16 g of white crystalline hetacillin ester hydrochloride are obtained. The spectra are consistent with the desired structure. Bio tests show an activity of 764 Y / mg based on hetacillin.

analysis

Cl calculated: 7.54

found: 7.72

example

C. , 65 H OO N , 94 53 , 44 6, 95 8th , 74 53 5, 8th

Acylation of p-toluenesulfonate salt of methoxymethyl 1-6-amino-

penicillinate;

1.3 g (3 mmol) of the p-toluenesulfonate salt of methoxymethyl-6-amino-; penicillinat are mixed with 40 ml of acetone and 10 ml of water. The mixture is cooled ^{between 0} ° C. and 5 ^{° C.} 1.2 g of 6 mmol of phenylglycyl chloride hydrochloride are added to the cooled mixture with vigorous stirring. The pH of the reaction mixture is / if necessary, kept between 2.0 'and 2.8 by adding 10% sodium hydroxide. After the reaction has ended, the pH is adjusted to between 6.5 and 7.0, the mixture is filtered and diluted to 200 ml with acetone, a solution of the methoxymethyl ester of ampicillin being obtained.

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Example 8 ''

Ampicillin methoxymethyl ester hydrochloride

37.1 g (0.1 mol) of sodium amphicillin are dissolved at 25 ° C. in 150 ml of dimethylacetamide. The solution is cooled to ⁰ ° C. to 5 ^° C. and 8.0 ml (0.1 mol) of chloromethyl methyl ether are added. After one

Has stirred for 1 hour, thin layer chromatography reveals no more remaining sodium amphicillin. The solution is poured into 200 ml cold buffer with pH 7 and. » extracted three times with 100 ml portions of methylene chloride. The methylene chloride extracts add to about 150 ml of cold water and adjust the pH with ChIoJr hydroic acid to 1.6. The water layer is separated and adjusted to pH 6.8 with dilute sodium hydroxide and extracted three times with 100 ml portions of methylene chloride. The methylene chloride liquors are dried over sodium sulfate and concentrated under reduced pressure to give a colorless oil which on thin layer chromatography is a Zone shows. The oil is dissolved in 2-propanol, cooled and HCl in 2-propanol is added. This solution is then added to 700 ml cold, well-stirred ether. A white precipitate forms which, after stirring for 15 minutes, is filtered off and washed with cold ether. 12 g of a white solid which is soluble in water are obtained. The IR and NMR spectra are available consistent with the structure for the hydrochloride salt of the methoxymethyl ester of ampicillin. Bioactivity related on ampicillin gives an activity of 682 γ / mg.

A useful embodiment of the process of the invention is a continuous series of reactions without isolating or recovering intermediates. For example, the potassium salt of phenoxymethylpenicillin is esterified with chloromethyl methyl ether in methylene chloride at a temperature between ⁰ ° C. and 30 ^{° C.} The methylene chloride solution of the ester is then successively mixed with phosphorus pentachloride,

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3 09812/1258

Treated methyl alcohol and water to complete the removal of the phenoxymethyl side chain and obtain a methylene chloride solution containing the methoxymethyl ester of 6-aminopenicillanic acid. This solution ¹ is then used in the acylation reaction in which phenylglycyl chloride hydrochloride is added to the solution to give a methylene chloride solution of the ampicillin ester. In the last stage, the solution of ampicillin ester is treated with acetone at pH 7.5 to 8.5 and left until the formation of hetacillin ester has proceeded. Hetacillin itself is obtained from the organic phase by treatment with a strong acid and water, for example 3 η water-chlorinated;

»I

chemical acid, obtained. The hetacillin is in the liquid!

Phase insoluble and crystallized.

Oral absorption of the hetacillin ester is as shown in Table I. shown, rated and compared to ampicillin and hetacillin. Each time the antibiotic is given to a group of 8 males Orally administered to mice in equivalent amounts. Blood levels are determined by plate culture tests for Bacillus subtilus determined and given as γ / ml ampicillin.

These data show that the hetacillin ester absorption is at Mice in the blood of the mice occurs more rapidly than with either hetacillin or ampicillin, which results in a more rapid achievement from peak levels of the antibiotic in the blood.

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M / 12 262

TABEL

Blood levels after oral administration to mice

link

.Dose. (mg. Ag.)

Blood level (γ / ml) 0.5. 1 2 3 ". ~ 5 Hours after administration

Ester ¹ 126 Λ: ⁴⁹ 3.49 1.43 0.42 Hetacillin 115 4.30 5.00 2.10 0.38 Ampicillin 100 5.79 5.34 1.91 0.44 Ester ² 126 10.20 4.48 . 1.53 0.42 ^: 2
Ampicillin 100 5.35 3.67 1.45 0.51 Hetacillin 115 2.52 2.81 1.46 0.52

administered in 5% sodium bicarbonate solution administered in distilled water

Elimination and more absorption data obtained from '■ studies in rats urine, as shown in Table II. The j compounds are administered in Ό, 0001 molar phosphate buffer! is enough and the amount of antibiotic recovered becomes

indicated as ampicillin ..

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M / 12 262

TABLE II

Recovery from urine of methoxymethyl ester of hetacillin after oral administration to rats

link

Dose (mg / kg)

Number of d.

% Recovery

Hours after administration _{06 624 024}

Ester 63 5 ^k 5 17, 09 0, 56 17th , 65 Hetacillin 57, 5 4, 42 0, 52 4th , 94 Ampicillin 50 5 ^V 6, 13th 0, 36 6th , 49

Rapid appearance of the antibiotic in the urine indicates that it is suitable for the treatment of urinary tract infections ".

In addition to being a useful intermediate in the manufacture of hetacillin, the methoxymethyl ester has important antibiotic properties of hetacillin. This compound is due to its ability to more rapidly peak blood serum levels to yield compared to sodium amphicillin, auc! von Four as an antibiotic. When trying on beagle dogs the methoxymethyl ester of hetacillin shows peak blood levels i approximately 15 to 20 minutes after administration. Lace mirror j for sodium amphicillin occur about 1 hour after administration j under comparable conditions.

One of the factors in the evaluation of antibiotics is the biological half-life of the antibiotic. With beagle dogs the methoxymethyl ester of hetacillin has a half-life

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ti

of about 1.2 hours. Under ^{comparable conditions:} Sodium amphicillin has a half-life of only 30 to 40 minutes. In these tests, the concentration of the antibiotic is measured by bio tests.

Further experiments show that the methoxymethyl ester of hetacillin ' is more favorably distributed over the body tissue. Tests carried out on Beagle dogs show that the Ester has a significantly lower volume of distribution, namely the drug appears in a larger volume of fluid resolved as compared with sodium amphicillin. Provisional ^ It is estimated that the ester is twice as distributed as sodium amphicillin.

! Table ΙΙΪ below shows data on the therapeutic activity of methoxymethyl esters of hetacillin and ampicillin, '. expressed in terms of the dose necessary to protect 50 % of j mice exposed to a test organism. I. It can be seen that the ester is generally equivalent to known good antibiotics against a susceptible organism. j

TABE L L E III

Chemotherapeutic activity of ampicillin, hetacillin and , -. . . _ - ι

j the methoxymethyl ester of hetacillin and ampicillin according to j. oräle-f administration to "mice, ^fi: e infected with Escherichia coli

t * ι

ί "are-. ι

link -Ampicillin carrier _ buffer oral PD ₅ Q -mg / kg ⁺ Hetacillin 21 - .. E. eoli A 15119 He tacilline ster Test / 1 .. , ... test 2 (1) Ampicilin ester H ^ O 70 80 (2) H ₂ O 70 76 (3) H ₂ O 70 50 (4) H ₃ PO ₄ 50 54

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M / 12 262

j All compounds are administered orally in equimolar concentrations to mice 1 hour after exposure to the bacteria administered.

= Dose that protects 50% of the animals.

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3 0 981 TI 125 «

Claims (9)

M / 12 262 Pat ent spray e 1. Process for the preparation of a compound of the formula (I)! 1 CH - - y CH \ / · 3 - R- \ I. C -
I! N - ^ CHo
J. 0 - CH- .COOCH ₂ OCH ₃ j where R is the group (II) or group (III) - NH - 3090 1 2/1258 means, characterized in that methoxymethyl-6-aminopenicillinate of formula (IV) NH ₂ -CK C II ^CH 3 O = N CH- COO CH ₂ OCH ₃ acylated, forming the methoxymethyl ester of ampicillin, and optionally this ampicillin ester with acetone converts, forming the methoxymethyl ester of hetacillin. 2. The method according to claim 1, characterized in that the methoxymethyl-6-aminopenicillinate by deacylating of a penicillin ester of the formula (V) R-CO-NH 0 -CH- [■ = c - - CH I. - N C ^ CIi- COOCH ₂ OCH ₃ * ■ - ι ί. will be produced. 3. The method according to claim 1, characterized in that the resulting methoxymethyl ester of hetacillin is treated to remove the methoxymethyl ester group, and that itself resulting product is obtained. 309812 / 125Γ m / 12 262 2244815 4. The method according to claim 3 _t, characterized in that this product is obtained as a pharmaceutically acceptable non-toxic salt thereof. ^ 5. The method according to claim 2> 'characterized in that R denotes a phenoxymethyl group. 'j ι ■ 6. Connection of the formula CH- _c Ö wherein R is the group of the formula (II) or the group of the formula (III;) ö Ji = y \ means. - 25 - 3Ό9812 / 1258 Sh 7. The methoxymethyl ester of hetacillin. 8. The methoxymethyl ester of ampicillin. t 9., The compounds according to claim 6 to 8, prepared according to the method of claim 1. - 26 - 309812/1258