Novel inhibitors of tyrosinase produced by the 4-substitution of TCT (П).

Novel Tyrosinase Inhibitors of 4-functionalized Thiophene-2-carbaldehyde thiosemicarbazone (TCT) derivatives (1-8) had been synthesized and Spectrofluorimetry, 1H and 13C NMR titration and Molecular docking had been used to investigate their inhibitory activities and mechanisms on tyrosinase. The results showed that the inter-molecular interactions or hydrogen bond formation by increasing length of carbon chain or introducing benzene ring to the 4-functionalized ester group promoted or stabilized formation of complexes between modifier and tyrosinase, and enhanced the inhibitory activity of modifiers. The inhibitory activity of 4-benzoy methoxy-TCT was much stronger than that of any other synthesized tested modifiers, which was well explained by molecular docking and further verified by spectrofluorimetry and NMR titration by assuming that there existed an inter-molecular interaction besides formation of hydrogen bonds between the amino acid residues ASN260, GLU256, HIS85 of enzyme and the modifier.We concluded that 4-benzoy methoxy substitution of TCT was a good route obtaining novel tyrosinase inhibitors and deserved further studies.