Xanthene and thioxanthene derivatives, compositions thereof and a method of preparation thereof

摘要

The present invention relates to novel xanthene and thioxanthene derivatives of the following general formula: ##STR1## wherein Y represents sulfur or oxygen, R.sup.1 represents hydrogen, chlorine, trifluoromethyl or dimethylsulfamoyl, R.sup.2 represents hydrogen or fluorine; and R.sup.3 and R.sup.4 each represents hydrogen or methyl, provided that R.sup.3 and R.sup.4 may not both represent hydrogen, or R. sup.3 and R.sup.4 taken together with the nitrogen atom form a piperazine or piperidine ring optionally substituted in the 4-position by a methyl group or a 2-hydroxyethyl group, if desired, esterified with an aliphatic carboxylic acid having from one to seventeen carbon atoms inclusive, as well as non-toxic acid addition salts thereof.