Synthesis and cytostatic activity of the antitumor antibiotic chartreusin derivatives

In order to overcome the rapid biliary excretion of chartreusin, which diminished its activity when administered iv, a series of 3',4'-O-substituted derivatives of chartreusin were synthesized. Exo-type of 3',4'-O-benzylidene-chartreusin was found active both by ip and iv administration. Therefore, this compound was selected for further modification on its 6-phenol to obtain broader spectra and better pharmacokinetic parameters than the original compound. Several 6-O-acyl-3',4'-O-exo-benzylidene-chartreusins had high antitumor activity against some murine tumors both by iv and po administration.