An efficient total synthesis of trilepisiumic acid

Abstract

Total synthesis of trilepisiumic acid (4-((3-(3,4-dihydroxyphenyl)acryloyl)oxy)-3-hydroxybenzoic acid) isolated from Trilepisium madagascariense was carried out. Doebner condensation of 3,4-dimethoxybenzaldehyde with malonic acid yielded 3,4-dimethoxycinnamic acid (2). Esterification of the latter with vanillin afforded 4-formyl-2-methoxyphenyl-3-(3,4-dimethoxy phenyl)acrylate (3) followed by permanganate oxidation in acidic medium provided the corresponding acid 4. Finally, demethylation of 4 was achieved by refluxing in hydrobromic acid to unveil the trilepisiumic acid (1).

Keywords::

• trilepisiumic acid
• cinnamic acid
• Trilepisium madagascariense