[Novel derivatives of diosgenin: design, synthesis and anti-tumor activity].

Diosgenin can inhibit the growth of A375 and K562 cell lines and induce their apoptosis with an effect on pro-apoptotic members of Bcl-2 family. To study the SAR of diosgenin derivatives, and to improve the anti-tumor activity of diosgenin, a series of novel diosgenin derivatives were designed and synthesized. Their anti-tumor activities in vitro were evaluated. The results revealed that most of the new derivatives had potent effects against K562, A375 and A549 (three tumor cell lines) in vitro, and had no or less effect against H293 and L02 (two normal cell lines). Particularly, some compounds (e.g. 1, 6-8) showed excellent activities on K562 with IC50 values ranging from 1.96 to 4.35 micromol x L(-1).

[Structure-activity relationship of diosgenin derivatives as Bcl-2 antagonists].

The purpose of this paper is to clarify the structure-activity relationship of anti-tumor activity of diosgenin derivatives in vitro. Study has found that diosgenin can inhibit the reproduction of tumor cells by inducing apoptosis and the main target spot of this effect is Bcl-2. Based on the characteristics of pharmacophoric points' of the three-dimensional pharmacophore for Bcl-2 inhibitors, we have docked lots of diosgenin derivatives with Bcl-2, then synthesized 31 compounds of them, finally assessed the anti-tumor activity of the diosgenin derivatives in vitro against A375, A549, HepG-2 and K562. Preliminary studies of SAR have indicated that the aliphatic esters, and aromatic esters of diosgenin without F ring have no anti-tumor activity in vitro. The triazole bromides of diosgenin all achieve fairly good anti-tumor activity in vitro, and those with larger hydrophobic group have the better activity. The stronger is the hydrogen bonding interaction and dipole-dipole interaction of the heterocyclic of diosgenin and diosgenin without F ring and the acid ester of diosgenin without F ring, the better is the activity of derivatives.