New acetylenic norlignan compounds from rhizomes of Curculigo crassifolia

Two pairs of diastereoisomeric acetylenic norlignan compounds with PhCH(OR(1))CH(OR(2))CH(2)C triple bond CPh skeleta: (1R, 2R)-1-O-methylnyasicoside (1) and (1S, 2R)-1-O-methylnyasicoside (2), and (1R, 2R)-crassifogenin D (3) and (1S, 2R)- crassifogenin D (4), were isolated from the ethanolic extract of rhizomes of Curculigo crassifolia. Compounds 3 and 4 are new and their structures were elucidated on the basis of spectroscopic evidence and comparisons with literature data.