Isocartormin, a novel quinochalcone C-glycoside from Carthamus tinctorius.

A new semi-quinonechalcone C-glycoside isocartormin along with cartormin and safflomin C were isolated from the water extract of Carthamus tinctorius L. The structure of isocartormin was determined by extensive analysis of HR-MS, 1D- and 2D NMR data, and by comparison with those of cartormin reported previously by our group. Isocartormin was identified as a diastereoisomer of cartormin with a reverse configuration at C-18.