Antibacterial cephem carboxylic acid salts - with lysine or arginine are water soluble and are given by intramuscular injection

摘要

The L-lysine and L-arginino salts of 7- (cyanomethylthio)-acetamido -3- 2-(5-methyl-1,3,4-thiadiazolyl)thio methyl - delta3 - cepheme-4-carboxylic acid (I) are new (where R = - (CH2)4-CH(NH2)COOH or -C(=NH)NH-(CH2)3 CH(NH2)COOH). The salts are active against Gram positive and negative bacteria. They are sufficiently soluble to be administered by intramuscular injection, unlike the sodium salt which has to be given orally. This gives a more raid absorption into the blood stream and a lnger duration of action. In an example the L-lysine salt was prepd. by heating 22.8g of the free acid at 60 degrees C in 200ml ethanol and 6.6g L-lysine in 50 ml ethanol at 60 degrees C added. The yield of L-lysine salt was 72% m.pt. 215-218 degrees C.