Antioxidant phenolic compounds from rhizomes of Curculigo crassifolia.

A pair of new phenolic glycosides, crassifoside G (5) and isocrassifoside G (6), along with five known phenolic compounds (1-4 and 7), were isolated from the ethanolic extract of the rhizomes of Curculigo crassifolia. Their structures were established by spectroscopic techniques and chemical methods. Most of the isolated compounds exhibited strong antioxidant activity in the 1, 1-diphenyl-2-picryldydrazyl (DPPH) radical scavenging assay.