Phenolic Glucosides from Dendrobium aurantiacum var. denneanum and Their Bioactivities

Abstract

A new 8,4¢-oxyneolignane glucoside 1 has been isolated from the stems of Dendrobium aurantiacum var. denneanum together with six known phenolic glucosides 2-7. The structure of the new compound, including its absolute configuration, was determined by spectroscopic and chemical methods as (–)-(7S,8R,7¢E)-4-hydroxy-3,3¢,5,5¢-tetramethoxy-8,4¢-oxyneolign-7¢-ene-7,9,9¢-triol 7,9¢-bis-O-β-D-glucopyranoside (1). In the in vitro assays, compound 1 and (-)-syringaresinol-4,4¢-bis-O-β-D-glucopyranoside (2) showed evident activity against glutamate-induced neurotoxicity in PC12 cells. Shashenoside I (4) showed a selective cytotoxic activity with the IC50 value of 4.17 μM against the acute myeloid leukemia cell line MV4-11, while it was inactive against 10 other human tumor cell lines.

Keywords

• Dendrobium aurantiacum var. denneanum
• lignan glucosides
• phenylpropanoid glycosides
• bioactivities