Pharmaceutically acceptable salts of 20(s)-camptothecins

Abstract

Described are pharmaceutically acceptable salts of a compound of formula (I) its tautomeric forms, its stereoisomers or its polymorphs, which is obtained by treating the compound of formula (I) with an acid selected from the group consisting of hydrohalo acid selected from the group consisting of hydrochloric acid or hydrobromic acid, acetic acid; sulfuric acid, nitric acid, phosphoric acid, boric acid, perchloric acid, tartaric acid, maleic acid, citric acid, methanesulfonic acid, benzoic acid, ascorbic acid, salicylic acid and benzene sulfonic acid wherein R1 represents substituted (C1–C6) alkyl wherein the substituent(s) is selected from mono (C1–C6) alkylamino or di (C1–C6) alkylamino; R2 represents hydroxy; R3, R4 and R5 represent hydrogen; and R6 represents hydrogen, or substituted (C1–C6) alkyl, wherein the substituent(s) is selected from halogen, hydroxy or (C1–C6) alkoxy and methods for using these compounds.

Dependencies are inferred from the claim text.