Verfahren zur Herstellung von Stoffen mit antibakteriellen Eigenschaften

摘要

The invention relates to thiopenicillins of general formula wherein R1, R2 and R3 are each H, halogen, C1- 10 alkyl or C1- 10 alkoxy and R4 and R5 are H or C1- 10 alkyl and X is sulphur or oxygen, and salts thereof. The thiopenicillins are produced by reacting a reactive acylating derivative of the 3-carboxylic group of a penicillin of general formula wherein R1, R2, R3, R4 and R5 and X have the above meanings, with a source of sulphydryl groups in a non-interfering solvent. The pencillin reactant may be the acid chloride, acid bromide, anhydride or azolide and this may be reacted with H2S, sodium hydrosulphide or potassium hydrosulphide in an inert solvent such as dimethylformamide in the presence of a base such as triethylamine. Alternatively, the thiopenicillins are produced by the acylation of 6-aminothiopenicillanic acid (Specification 1,078,077. Typical thiopenicillins are 6- (phenoxyacetamido) - thiopenicillanic acid, 6 - (a -isopropylphenoxyacetamido) - thiopenicillanic acid, 6 - (phenylmercaptoacetamido) - thio-penicillanic acid and 6-(4-methoxyphenylmercaptoacetamido) thiopenicillanic acid. The thiopenicillins have antibacterial activity against some penicillin-resistant organisms and are acid-stable. They may be formulated into pharmaceutical compositions for human or animal use or they may be added to animal feeds. They may be used for the treatment of mastitis in cattle.ALSO:An animal fed comprises a thiopenicillin as nutritional supplement, said thiopenicillin having the formula:- wherein R1, R2 and R3 are H, halogen, C1-10 alkyl or C1-10 alkoxy, and wherein R4 and R5 are H or C1-10 alkyl and X is sulphur or oxygen; or a salt thereof. A typical thiopencillin is 6-(phenoxyacetamido)-thiopenicillanic acid and its alkali metal, ammonium and amine salts.