Thieno[3,4-d]pyrimidin-4(3H)-thione: an effective, oxygenation independent, heavy-atom-free photosensitizer for cancer cells.

ABSTRACT: All-organic, heavy-atom-free photosensitizers based on thionation of nucleobases are receiving increased attention because they are easy to make, noncytotoxic, work both in the presence and absence of molecular oxygen, and can be readily incorporated into DNA and RNA. In this contribution, the DNA and RNA fluorescent probe, thieno[3,4-d]pyrimidin-4(1H)-one, has been thionated to develop thieno[3,4-d]pyrimidin-4(3H)-thione, which is nonfluorescent and absorbs near-visible radiation with about 60% higher efficiency. Steady-state absorption and emission spectra are combined with transient absorption spectroscopy and CASPT2 calculations to delineate the electronic relaxation mechanisms of both pyrimidine derivatives in aqueous and acetonitrile solutions. It is demon

SUBMITTER: Ortiz-Rodriguez LA 

PROVIDER: S-EPMC10445467 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature