Abstract
5-Selenothiazoles 4-7 were prepared through the reaction of triseleniumdicyanide 2 with 2-aminothiazole 3 in DMSO to form the 2-amino-5-selenocyanatothiazole 4, which was reduced with NaBH4 to give the di-selenide 6. Acetylation of seleno derivatives 4 or 6 with acetic anhydride formed the acetamides5 and 7. The interactions of compounds 4-7 with the double strain fish sperm deoxyribonucleic acid were investigated by spectrophotometric method and showed groove binding interaction with a binding constant of 10(4)M(-1). The calculated enthalpies, entropies, and Gibbs free energy change indicated that all the interaction processes were spontaneous and the hydrogen bond and Van der Waals interaction play main roles in the binding of 4-7 to FS-DNA. The molecular modeling results illustrated that compound binds to groove of B-DNA by relative binding energy of -4.3 to -6.2 kcal mol(-1). Preliminary biological studies were conducted, highlighting the effect of the di-selenide compounds. 6 and 7 exhibited good cytotoxicity against prostate (PC-3), liver (HepG2), and breast (MCF-7) cancer cell lines, consistent with the presence of nitrogen heteroatoms and extended delocalized systems correlating with strong cytotoxic performance.