Cytotoxic Sesquiterpenoids and Diarylheptanoids from the Rhizomes of Curcuma elata Roxb

The present study was aimed to investigate the chemical constituents of Curcuma elata Roxb. (Zingiberaceae) rhizomes originating in Thailand. Ten sesquiterpenes, germacrone (1), curzerenone (2), isofuranodienone (3), furanodienone (4), curdione (5), neocurdione (6), zederone (7), curcumenone (8), 13-hydroxygermacrone (9) and zedoarondiol (10), and four diarylheptanoids, 3-hydroxy-5-platyphyllone (11), (3S)-1,7-bis(4-hydroxyphenyl)-(6E)6-hepten-3-ol (12), centrolobol (13) and (3S)-1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)-(6E)-6-hepten-3-ol (14) were isolated for the first time from the rhizomes of this plant. The structures of the isolated compounds were identified by comparison of the spectroscopic and physical data with those of the reported values and the stereochemistry at the asymmetric carbon was determined by the modified Mosher’s method and, in some cases, was confirmed by comparison of optical rotation data with literature. Compounds 12 and 13 exhibited strong cytotoxic activity against KB cell line, whereas compounds 4, 9 and 12-14 showed strong cytoxicity against NCI-H187 cell line.