Solid-Phase Microwave Assisted Synthesis of Curcumin Analogs

Abstract

Turmeric contains three important analogs, curcumin, demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC), collectively called as curcuminoids. Curcumin, the most abundant of these curcuminoids is reported to have antioxidant, anti-inflammatory, neuroprotective, antimicrobial, nematocidal, antimutagenic, anticarcinogenic, antiretroviral and chemopreventive activities. Curcumin (a symmetric diketone) analogs 3a-e were synthesized fromdiketones and aromatic aldehydes using solid phase microwave irradiation method in presence of boric acid in diethanolamine, acetic acid (1:1) with reduced reaction time and enhanced %yield. Various clays like Alumina (neutral), Silica gel and Montmorillonite K 10 were used as solid phase catalysts where alumina was found to be efficient in the synthesis of curcumin analogs.

Hybrid Synthetic and Computational Study of an Optimized, Solvent-Free Approach to Curcuminoids

“…The solvent-free synthesis of curcuminoids was explored as part of ongoing efforts 17 to expand the applicability of solvent-free approaches, toward small, biologically important molecules, as a means to develop greener, more atom-economical processes. Despite the report of the solid-state synthesis of curcumin and related compounds, 18 to the best of our knowledge, there has been no investigation of the applicability of solvent-free approaches for the syntheses of such compounds. The present combined mechanistic and crystallographic study has yielded crystal structures of three curcuminoids and one reaction intermediate.…”