Silicon photosensitizers in cancer therapy: Theoretical studies on novel 5-methoxypsoralens

Three novel silicon photosensitizers (PSs) are discovered with prospects to be utilized in psoralen ultra-violet A (PUVA) cancer therapy, at B3LYP/6-311++G** level of theory. They include 5-methoxysilolo[3,2-g]chromen-2(8H)-one (1), 5-methoxybenzo[4,5]silolo[3,2-g]chromen-2(10H)-one (2), and 11-methoxybenzo[c]silolo[3,2-g]chromen-5(8H)-one (3). Structures 1-3 exhibit intense narrow absorption peaks in the ultra violet A (UVA) therapeutic window and show T-1 energies necessary to activate the ground state triplet molecular oxygen (O-3(2)) to its singlet excited state (O-1(2)).