Synthesis of novel 6,6′-methylene-bis-[3-(2-anilinoacetyl)-4- hydroxycoumarin] derivatives

Abstract

The synthesis of novel 6,6′-methylene-bis-[3-(2-anilinoacetyl)-4- hydroxycoumarin] derivatives 6a-f was achieved in excellent yields from 6,6′-methylene-bis-[3-(2-bromoacetyl)-4-hydroxycoumarin] 5 and various arylamines. 5,5′-Methylene-bis-ethylsalicylate 3 was obtained by the esterfication of 5,5′-methylene-bis-salicylic acid 2 with ethanol, which was in turn obtained from salicylic acid 1 and formaldehyde. Cyclocondensation of 3 with ethyl acetoacetate resulted in 6,6′-methylene-bis-[3-acetyl-4- hydroxycoumarin] 4, which on selective α-bromination with molecular bromine in the presence of montmorillonite K10-AlCl3 catalyst, in chloroform-ethyl acetate binary solvent mixture at room temperature, afforded the compound 5 in excellent yield. All the newly synthesized compounds were characterized by their spectral data. © 2008 Pharmaceutical Society of Japan.