Leptocarposide: a new triterpenoid glycoside from Ludwigia leptocarpa (Onagraceae)

A new triterpenoid bidesmoside (leptocarposide) possessing an acyl group in their glycosidic moiety (1), together with the known luteolin-8-C-glucoside (2) and 1-O-β-D-glucopyranosyl-(2S,3R,8E)-2-[(2'R)-2-hydroxypalmitoylamino]-8-octadecen-1,3-diol (3) was isolated from the n-butanol-soluble fraction of whole plant of Ludwigia leptocarpa (Nutt) Hara (Onagraceae). Structure of compound 1 has been assigned on the basis of spectroscopic data ((1)H and (13)C NMR, (1)H-(1)H COSY, HSQC, HMBC, and ROESY), mass spectrometry, and by comparison with the literature. This compound was further screened for its potential antioxidant properties by using the radical scavenging assay model 2,2-diphenyl-1-picrylhydrazyl and reveals non-potent antioxidant activities, while compound 2 shows SC50 of 0,038 mM.