ABSTRACT
A new taraxer-based triterpenoid ester, taraxer-14-en-30-al-3β-O-palmitate(1), was isolated from the whole plant of Wedelia trilobata, along with six known compounds, ent-kaur-16-en-19-oic acid(2), 16α-hydroxy-ent-kauran-19-oic acid(3), tara-xerol(4), β-amyrin(5), 1β-acetoxy-4α, 9α-dihydroxy-6β-isobutyroxyprostatolide(6), and stigmasterol(7). Their structures were elucidated with use of a combination of spectroscopic techniques(IR, HR-ESI-MS, 1 D, 2 D NMR data) and chemical methods.
Subject(s)
Magnetic Resonance Spectroscopy , Molecular Structure , Triterpenes , WedeliaABSTRACT
Objective To investigate the chemical constituents of Wedelia trilobata.Methods The chemical constituents were separated by chromatography and their structures were determined by physico-chemical constants and spectral analyses.Results Eleven compounds were isolated and identified as grandiflorenic acid(1),1?-acetoxy-6?,9?-dihydroxy-4,10?-dimethyl-5?H,7?H,8?H-endesm-3-en-8,12-olide(2),1?-acetoxy-4?-hydroxy-6?-isobutyryloxy-9?-isovaleryloxyprostatolide(3),16?-hydroxy-ent-kauran-19-oic acid(4),(3R,4R,6R)-3,4-dihydroxy-1-menthene(5),trilobolide-6-O-isobutyrate(6),1?-acetoxy-4?,9?-dihydroxy-6?-isobutyroxyprostatolide(7),16?,17-dihydroxy-ent-kauran-19-oic acid(8),daucosterol(9),protocatechualdehyde(10),and caffeic acid(11).Conclusion All the compounds are isolated from W.trilobata for the first time except compounds 6 and 7.Compounds 2 and 3 are new sesquiterpene lactones,named as trilobolide A and 1?-acetoxy-4?-hydroxy-6?-isobutyryloxy-9?-isovaleryloxyprostatolide,respectively.