GB777380A - New salts of penicillin with alkylene diamines and processes of making them - Google Patents

Abstract

The invention relates to salts of penicillin with alkylene diamines of general formula <FORM:0777380/IV(b)/1> wherein each R1 substituent represents an alkyl radical containing from 1 to 7 carbon atoms and alk stands for an alkylene radical of 2 to 12 carbon atoms either in a straight chain or branched chain form. The salts are prepared by reacting penicillin, or a salt thereof, with the appropriate alkylene diamine, or a salt thereof, the reaction being carried out in the presence of a solvent. The free acid and base is reacted in a non-aqueous solvent such as ether, acetone, ethyl acetate and amyl acetate. Salts are reacted in an aqueous medium. The penicillin salt may be an alkali metal or an alkaline earth metal; and the penicillin penicillin G, dihydro F, X, K or a mixture thereof. The diamine salt may be a salt with an inorganic or organic acid, e.g. acetic, lactic, succinic, malic, aconitic or tartaric acid. The salts of penicillin and the diamine may be mono- or di-salts. The example relates to the preparation of N,N1-di-(a -methylbenzyl ethylene diamine dipenicillin. The salts are non-toxic and may be used therapeutically. They are also used in the purification of penicillin. The N : N1-disubstituted diamines may be prepared by reacting a ketone of formula <FORM:0777380/IV(b)/2> where R1 stands for a 1 to 7 carbon alkyl group with an alkylene diamine to form a di-imine which is then reduced catalytically by means of hydrogen. In the example, acetophenone is reacted with ethylene diamine and the di-imine so produced is hydrogenated in glacial acetic acid using a platinum oxide catalyst. Specification 716,556 is referred to.