Highly oxygenated stigmastane-type steroids from the aerial parts of Vernonia anthelmintica Willd.

Nine new highly oxygenated stigmastane-type steroids, vernoanthelcin A-I (1-9), and two new stigmastane-type steroidal glycosides, vernoantheloside A and B (10 and 11) were isolated from the aerial parts of Vernonia anthelmintica Willd. The structures of compounds 1-11 were determined on the basis of IR, MS, 1D-NMR, and 2D-NMR, and their absolute configurations were deduced using single-crystal X-ray diffraction and the CD exciton chirality method. Compounds 1, 5, 7, 9 and 10 were tested for their effects on estrogen biosynthesis in human ovarian granulosa-like cells (KGN cells).

2-[(1R*,4R*)-1,4-Dihy-droxy-cyclo-hex-yl]acetic acid.

The title compound, C(8)H(14)O(4), is an isolation product of the aerial parts of Senecio desfontanei. The acetic acid group is oriented at a dihedral angle of 48.03 (9)° with respect to the basal plane of the cyclo-hexane-1,4-diol chair.