A simple route to a novel acid-sensitive 20(S)-O-linked camptothecin norcantharidin acid ester derivative.

A facile synthetic method was developed for a novel acid-sensitive camptothecin norcantharidin acid ester derivative I. The total yield can reach 71%. This method provides several advantages, including high yield and simple working procedure for the synthesis of analogues. The new synthetic compound I has been shown to exhibit better solubility and similar activity against tumour cell lines.