CORCHORUSOSIDE-A, CORCHORUSOSIDE-B, CORCHORUSOSIDE-C, CORCHORUSOSIDE-D, AND CORCHORUSOSIDE-E, NEW CARDIOTONIC OLIGOGLYCOSIDES FROM THE SEEDS OF CORCHORUS-OLITORIUS L. (MOROHEIYA)

The methanolic extract of the seeds of Corchorus olitorius L. (Morohei ya) was found to show inhibitory effect against Na+-K+-ATPase and posi tive inotropic activity in the guinea pig isolated atria. Through bioa ssay-guided separation from the methanolic extract, new cardenolide ol igoglycosides called corchorusosides A, B, C, D, and E were isolated t ogether with six known cardenolide oligoglycosides. The structures of new corchorusosides were determined on the basis of chemical and physi cochemical evidence. All cardenolide oligoglycosides from the seeds sh owed potent inhibitory activity against Na+,K+-ATPase, which was equiv alent to those of digitoxin and ouabain. The methanolic extract, glyco side fraction, and principal glycoside showed potent acute toxicity by intraperitoneal administration, whereas they showed little acute toxi city by oral administration. Furthermore, by means of HPLC quantitativ e analysis of the cardiotonic oligoglycosides, it was found that the g lycosides mainly distributed in the seeds, while the edible parts such as fresh young leaves and stems contained only trace amount.