Azasteroids from diosgenin: Synthesis and evaluation of their antiproliferative activity.

In this work, we report the synthesis of two new azasteroids through the modification of the A and B rings of diosgenin 1. The 4-azasteroid derivative 12 was prepared in three steps using the α,ß-insaturated-3-keto compound 11 as a precursor, which was first oxidized with KMnO4/KIO4 followed by an oxidative cleavage of ring A, and subsequently cyclized with an ammonium salt, under focused microwave irradiation for a short time of 3 min. A second azasteroid was synthesized, for which the key step was the Beckmann rearrangement of ring B of the oxime 16, affording the lactam-type enamide 17 in good yield. The methodologies developed for the synthesis of the precursors derivatives 10 and 11 contribute to improved yields, compared to those reported in the literature. The biological activity of the azasteroidal compounds 12 and 17 and their precursors has been evaluated in cervical cancer cells (HeLa), colon (HCT-15), and triple negative breast cancer (MDA-MB-231) lines.

Diosgenin hemihydrate.

Diosgenin [or (22R,25R)-spirost-5-en-3ß-ol] is the starting material of the Marker degradation, a cheap semi-synthesis of progesterone, which has been designated as an Inter-national Historic Chemical Landmark. Thus far, a single X-ray structure for diosgenin is known, namely its dimethyl sulfoxide solvate [Zhang et al. (2005 ▶). Acta Cryst. E61, o2324-o2325]. We have now determined the structure of the hemihydrate, C(27)H(42)O(3)·0.5H(2)O. The asymmetric unit contains two diosgenin mol-ecules, with quite similar conformations, and one water mol-ecule. Hy-droxy groups in steroids and water mol-ecules form O-H⋯O hydrogen-bonded R(5) (4)(10) ring motifs. Fused edge-sharing R(10) rings form a backbone oriented along [100], which aggregates the diosgenin mol-ecules in the crystal structure.