Synthesis of Naturally Occurring Curcuminoids and Related Compounds

✍ Scribed by Pedersen, Uffe ;Rasmussen, Preben B. ;Lawesson, Sven-Olov

• Publisher: John Wiley and Sons
• Year: 1985
• Tongue: English
• Weight: 669 KB
• Volume: 1985
• Category: Article
• ISSN: 0947-3440
• DOI: 10.1002/jlac.198519850805

✦ Synopsis

Abstract

Six known naturally occurring curcuminoids^1)^ like curcumin, [5‐hydroxy‐1,7‐bis(4‐hydroxy‐3‐methoxyphenyl)‐1,4,6‐heptatrien‐3‐one (4a)] and 31 other analogs (Scheme 1) have been synthesized. Among them, 25 curcuminoids were prepared by condensing different substituted 2,4‐pentanediones and benzaldehydes. The boron complex 12 has been used to avoid Knoevenagel condensation at C‐3 of 2,4‐pentanedione. Some curcuminoids containing hydroxy groups in the aromatic moiety have been acylated. Alkylation of the tetrabutylammonium salt of 5‐hydroxy‐1,7‐diphenyl‐1,4,6‐heptatrien‐3‐one (1a) by benzyl bromide gave only C‐alkylated 4‐benzyl‐1,7‐diphenyl‐1,6‐heptadiene‐3,5‐dione (1d^*^). The ^13^C NMR data, the UV absorptions, and the tautomerism of the curcuminoids are discussed.