Three new sesquiterpenes from roots of Curcuma longa

OBJECTIVE: To study the chemical constituents from the roots of Curcuma longa. METHODS: The structures of the compounds were elucidated based on extensive spectral analysis, including 1D and 2D NMR, MS, UV, and CD analysis. RESULTS: Two new sesquiterpene compounds (1S,2R,5R,7S,8R)-2,8-epoxy-5-hydroxybisabola-3,10-dioen-9-one (1), (1R,2R,5R,7S,8R)-2,8-epoxy-5-hydroxybisabola-3,10-dioen-9-one (2), and a new natural product 6-(4-Hydroxymethylphenyl)-2-methyl-hept-2-ene-4-one (3) together with three known compounds ar-turmerone (4), 2-methyl-6-(4-hydroxyphenyl-3-methyl)-2-hepten-4-one (5) and 2-methyl-6-(4-hydroxyphenyl)-2-hepten-4-one (6) were isolated from C. longa root extract with 95% ethanol. CONCLUSION: In the study, three new compounds were isolated from C. longa, and their absolute configurations were determined.