Patent ID: 6111107
Filing Date: 2000-08-29
Classification: C07D

Abstract:
A method of forming esters of camptothecin or camptothecin derivatives, comprising:reacting an acyl heteroaromatic ion-based compound of the formula: ##STR15## wherein A is an anion;R.sub.1 is an aromatic or aliphatic acid residue;Y is O or S;Z is CH or N; andX is selected from the group consisting of ##STR16## where R.sub.2 and R.sub.3 are independently selected from the group consisting of C.sub.1-6 alkyls, C.sub.1-6 substituted alkyls, C.sub.3-8 branched alkyls, C.sub.3-8 cycloalkyls, aryls, substituted aryls, C.sub.1-6 alkyl aralkyls, C.sub.3-8 branched alkyl aralkyls and C.sub.3-8 cycloalkyl aralkyls;with a camptothecin or camptothecin derivative in the presence of a lanthanide.sup.III metal-based catalyst whereby an ester of a camptothecin or camptothecia derivative is formed.