RESUMEN
AIM To investigate the chemical constituents of the rhizomes of Dioscorea panthaica Prain et Burkill and look for new active compounds. METHODS The compounds were isolated with silica gel and HPLC, and their structures were elucidated on the basis of chemical evidences and spectral analysis (IR, ESI-MS, 1HNMR, 13CNMR, DEPT, 1H-1H COSY, HMQC, HMBC, NOESY). RESULTS Three steroidal saponins were isolated from the rhizomes of Dioscorea panthaica. They were elucidated as 26-O-β-D-glucopyranosyl-3β,26-diol-23(S)-methoxy-25(R)-Δ5,20(22)-diene-furosta-3-O-［α-L-rhamnopyranosyl-(1→2)-O-α-L-rhamnopyranosyl-(1→4)］-β-D-glucopyranoside (I), pseudoprotodioscin (II), 26-O-β-D-glucopyranosyl-3β,26-diol-25(R)-Δ5,20(22)-diene-furosta-3-O-α-L-rhamnopyranosyl-(1→2)-O-β-D-glucopyranoside (III). CONCLUSION Compound I is a new steroidal saponin and was named as dioscoreside C. Compound II and III were obtained from this genus for the first time.
RESUMEN
Repeated administrations of gangliosides extracted from Cervus nippon Temminek exerted remarkable facilitation action on the acquisition, retrieval and consolidation of memory in mice. It was able to increase the incorporations of [8H] Leucine into protein and [3H] Uridine into RNA in mouse brain tissue. It was suggested that the above-mentioned actions of gangliosides may be due to the promoting action for the synthesis of protein in brain tissue.