Synthesis and photochemical properties of photoactivated antitumor prodrugs releasing 5-fluorouracil

A new family of antitumor prodrugs ( 1-3) of 5-fluorouracil ( 5-FU) possessing photolabile 2-nitrobenzyl chromophores have been designed and synthesized to investigate the efficiency and mechanism of photoactivated 5-FU release upon UV-irradiation at lambda(ex) = 365 nm. The photoactivated prodrug 3 derived from conjugation of 2 with a tumor-homing cyclic peptide Cys-Asn-Gly-Arg-Cys ( CNGRC) was so designed as to manifest a tumor-targeting function.