Scheme 1. The synthetic route to novel tyrosinase inhibitors. Reagents and conditions: (a) i. TBDMSCl, DIEA, DCM, 0 °C to rt., 20 h; ii. K2CO3, MeOH/THF, rt., 3 h; (b) i. SOCl2, DCM, reflux, 5 h; ii. paeonol or thymol, NEt3, DCM, 0 °C to rt., overnight; (c) 2 M HF solution, THF, reflux., 1 h; (d) paeonol or thymol, EDCI, HOBt, DIEA, DCM, 0 °C to rt., overnight.
