Photobiological properties of furothiocoumarins in Saccharomyces cerevisiae.

Nine furothiocoumarins corresponding to psoralen, 8-methylpsoralen, 3-carbethoxy-8-methylpsoralen, 8-methoxypsoralen, pseudopsoralen, angelicin, isopseudopsoralen, allopsoralen and pseudoisopsoralen were synthesized by treating furocoumarins with phosphorus pentasulfide. Photobiological studies on haploid yeast cells (Saccharomyces cerevisiae) revealed that the furothiocoumarins exert some photoactivity on cell survival and the induction of mitochondrial damage. In most cases, the furothiocoumarins were less active than their furocoumarinic counterparts and exhibited a preference for a monofunctional type of action. A certain photochemotherapeutic activity can be suggested.