NEW PHENTHIAZINE DERIVATIVES

1,269,870. Phenothiazines. RHONE-POULENC S.A. 16 July, 1970, No. 34612/70. Addition to 1,186,973. Heading C2C. Compounds (I) and their acid addition salts, wherein R 1 is 1-methylpentadecyl or 1,1-dimethylpentadecyl are prepared by esterifying a 3-dimethylsulphamoyl - 10 - {3 - [4 - (2 - hydroxyethyl) piperidino] propyl phenothiazine with R 1 -CO-X, where X is the acid residue of a reactive ester, OH, OAlkyl, alkanoyloxy, alkenoyloxy or alkynyloyloxy. 2-Methylhexadecanoyl chloride and 2,2-dimethyl hexadecanoyl chloride are prepared from the corresponding acids. Pharmaceutical compositions comprise compounds (I) with a diluent or coating especially in forms for parenteral administration.