Studies on the constituents of fruits of Helicteres isora L.

Three new compounds; 4'-O-beta-D-glucopyranosyl rosmarinic acid (2), 4,4'-O -di-beta-D-glucopyranosyl rosmarinic acid(3) and 2R-O-(4'-O-beta-D-glucopyr anosyl caffeoyl)-3-(4-hydroxyphenyl) lactic acid named as 4'-O-beta-D-gluco pyranosyl isorinic acid (4) were isolated together with rosmarinic acid (1) from the fruit of Helicteres isora L. (Sterculiaceae), an Indonesian medic inal plant, The structures of these compounds, including the absolute stere ochemistry of 4, were elucidated by spectroscopic analysis and chemical mea ns. Compound 3 had greater scavenging activity against superoxide anion pro duced with xanthine and xanthine oxidase (XOD) than rosmarinic acid (1).