Patent GB-1379502-A (GB)
Title: 6- alpha- -w-guanidinoalkanoylamido acylamide- penicillanic acids
IPC: A61K31/43
Filed: 1972-04-24
Abstract: 1379502 Guanidine-penicillins PFIZER Inc 24 April 1972 [22 Feb 1972] 18985/72 Headings C2A and C2C The invention comprises compounds of the Formula I and pharmaceutically acceptable acid addition salts thereof, wherein R is hydrogen or acyloxy (C 1 -C 4 ) alkyl, wherein acyloxy is selected from (C 1 -C 4 ) alkanoyloxy, benzoyloxy and substituted benzoyloxy wherein the substituent is chloro, bromo, fluoro, (C 1 -C 4 ) alkyl, (C 1 -C 4 ) alkoxy or trifluoromethyl; R 1  is hydrogen, (C 1 -C 14 ) alkyl, (C 3 -C 6 ) cycloalkyl, 1,4-cyclohexadienyl, naphthyl, benzyl, phenethyl, indolylmethyl, furyl, thienyl, #-ethylthio (C 1 -C 4 ) alkyl, or Y-substituted phenyl wherein Y is hydrogen, nitro, di-(C 1 -C 4 ) alkylamino, (C 1 - C 4 ) alkanoylamino, (C 1 -C 4 ) alkyl, (C 1 -C 4 ) alkoxy, hydroxy, sulphamyl, chloro, bromo, fluoro, iodo or trifluoromethyl; R 2  is hydrogen or (C 1 -C 4 ) alkyl; or R 1  and R 2  when taken together with the carbon atom to which they are attached are cycloalkylidene of 3-10 carbon atoms; each of R 3 , R 4 , R 5  and R 6  is hydrogen, (C 1 -C 4 ) alkyl, benzyl or phenyl; or R 4  and R 5  when taken together with the guanyl moiety to which they are attached form a 5- or 6-membered heterocyclic ring selected from 2-imidazolyl, 2 - (2 - imidazolinyl), 2 - (1,4,5,6 - tetrahydropyrimidinyl) and 2-pyrimidinyl; X is alkylene having 1 to 7 carbon atoms, phenylene, cycloalkylene having 3 to 9 carbon atoms, propenylene whose methylene group is bound to the adjacent nitrogen; vinylenephenylene, methylene oxyphenylene orphenylenemethylene, each of which phenylene group is bound to the adjacent nitrogen; or X and N-R 3  when taken together form a 5- or 6-membered heterocyclic ring selected from pyrrolidyl and piperidyl ; or X and R 5  when taken together with the guanidino moiety to which they are attached form a 5- or 6-membered heterocyclic ring selected from 2-amino-2-imidazolinyl and 2-amino-(1,4, 5,6-tetrahydropyrimidinyl); or R 3  and R 4  when taken together with the guanidino moiety to which they are attached form a 5- or 6- membered heterocyclic ring selected from 2- imidazolino and 2-(1,4,5,6-tetrahydropyrimidino); or R 3  and R 5  when taken together with the guanidino moiety to which they are attached form a 5- or 6-membered heterocyclic ring selected from imidazolidino and hexahydropyrimidino. A process for preparing compounds of Formula I comprises reacting a 6-[(α-amino substituted)-acylamido]penicillanic acid or a suitable ester thereof, of the Formula II with an appropriate guanidino substituted acid of Formula III wherein Z is a hydroxy or a halo group. An alternative process for preparing compounds of Formula I comprises reacting a compound of Formula III-A with an appropriate S-alkylisothiourea of Formula III-B Guanidino substituted acids of Formula III wherein Z = OH may be prepared (1) by reacting an amino acid HOOC-X-NHR 3  with an S- alkylisothiourea R 4 N=C(-SR<SP>1</SP>)NR 5 R 6  to yield guanidino substituted acids of formula (2) by reacting the appropriate amino acid with benzoyl cyanamide to yield guanidino substituted acids of formula (3) by reacting the sodium salt of the amino acid HOOC-X-NH(CH 2 ) p -NH 2  with cyanogen bromide to yield guanidino substituted acids of Formula VI  (4) by reacting 2- (or 3-)pyrrolidine carboxylic acid with the appropriate S-alkylthiouronium chloride to yield guanidino substituted acids of Formula VII (5) by reacting the appropriate amino acid with 2 - mebhylthioimidazolinium iodide or 2- methylthio - 2 - (1,4,5,6 - tetrahydropyrimidinium)iodide to yield guanidino substituted acids of Formula VIII or (6) by reacting an amino acid with 2-chloropyrimidine or 2-chloroimidazole to yield guanidino substituted acids of formula wherein R 4  and R 5  when taken together with the guanyl moiety to which they are attached form an imidazolyl or 2-pyrimidinyl group. In many cases, the conversion of the guanidino substituted acids to the corresponding guanidino substituted acid chloride hydrochlorides is described.