dimethoxanate 10h-phenothiazine-10-carboxylic acid 2-[2-(dimethylamino)ethoxy]ethyl ester 2-(2-dimethylaminoethoxy)ethyl phenothiazine-10-carboxylate 2-(2-dimethylaminoethyloxy)ethyl phenothiazine-10-carboxylate phenothiazine-10-carboxylic acid 2-(2-dimethylaminoethyloxy)ethyl ester Dimethoxanate USP/EP/BP