Examples of pharmaceutically acceptable esters of the compound of formula (I) include carboxylic acid esters of the hydroxyl group in the compound of formula (I) in which the non-carbonyl moiety of the carboxylic acid portion of the ester grouping is selected from straight or branched chain alkyl...
These KA-6606, I, II, III and IV obtained as free bases can be converted to their acid addition salts by treatment with pharmaceutically acceptable inorganic or organic acids. Examples of such acids are inorganic acids such as hydrochloric acid, sulfuric acid and hydrobromic acid, and organic ...