Synthesis of novel diazaphosphinanes coumarin derivatives with promoted cytotoxic and anti-tyrosinase activities

A series of alpha-aminocarbonitriles 2a-h, obtained by a condensation reaction of 4-hydroxycoumarin with malononitrile and a series of arylaldehydes, was reacted with Lawesson's reagent to give the diazaphosphinanes 3a-h and 3a'-h' as diastereoisomers. All the synthesized compounds were characterized by spectroscopic means such as NMR (H-1, C-13, P-31) and MS. The synthesized compounds were evaluated for their cytotoxic activity in vitro against two tumor cell lines MCF-7 and HCT-116 and for their anti-tyrosinase effect. The results showed a moderate cytotoxic activity for most compounds and nearly all tested derivatives have been found considerable tyrosinase inhibitors. (C) 2016 Elsevier Ltd. All rights reserved.