Synthesis of 7-(4-methylphenyl)thiomethyl and 7-morpholylmethyl derivatives of natural phaeosphaeride A and their cytotoxic activity

The herein synthesized 7-(4-methylphenyl)thiomethyl and 7-morpholylmethyl derivatives of natural phaeosphaeride A have lower cytotoxic activity towards the human lung adenocarcinoma A549 cell line compared to phaeosphaeride A. The presence of exocyclic C=C bond and N–OMe group in such compounds is suggested to be a factor in their antitumor activity.