GB969664A - Penicillins - Google Patents

Abstract

Penicillins of the formula: <FORM:0969664/C1/1> wherein R stands for a hydrocarbon radical, optionally substituted, and wherein the thiophen ring may optionally be further substituted, and the salts thereof may be prepared by a process which comprises acylation of 6-aminopenicillanic acid with an appropriate acylating agent. Typical penicillins of the above formula are 6-[a -(thien-2-yl) propionamido]-, 6-[a -(thien-3-yl)-n-butyramido]-, 6-[a -(thien-2-yl)-n-butyramido]-, 6-[a -(thien-2-yl)-n-hexanamido]-, and 6-[a -isobutyl-a -(thien-2-yl)-acetamido]-penicillanic acid. a -(Thien-2-yl) butyryl chloride may be prepared by reacting ethyl a -(thien-2-yl) acetate with sodium hydride followed by ethyl iodide to form ethyl a (thien-2-yl) butyrate which is subjected to alkaline hydrolysis to give a -(thien-2-yl) butyric acid which is treated with thionyl chloride. Other suitable thien-2-yl acylating agents may be prepared similarly. a (Thien-3-yl) butyryl chloride may be prepared by reacting 3-(a -hydroxypropyl)thiophen with hydrogen chloride to give 3-(a -chloropropyl) thiophen, which is reacted with potassium cyanide to give a -(thien-3-yl) butyronitrile, which is hydrolysed to a -(thien-3-yl)-butyric acid, which is treated with thionyl chloride. The penicillins or their pharmaceutically acceptable salts may be incorporated in pharmaceutical compositions in forms such as tablets, granules, capsules, dispersible powders, solutions, suspensions or emulsions, or ointments.