Withanolides from Jaborosa cabrerae

MANUELA E. GARCÍA; ALEXIS WOLFEL; GLORIA E. BARBOZA; JUAN C. OBERTI; CARLA RÍOS-LUCI; JOSÉ M. PADRÓN; VIVIANA E. NICOTRA; ANA ESTÉVEZ-BRAUN; ANGEL G. RAVELO

San Pablo

Congreso; ESPCA on Natural Products, Medicinal Chemistry and Organic Synthesis; 2011

Universidad de San Pablo

The natural product estate has served as an invaluable resourcein the search for structurally novel lead agents of potentialtherapeutic value. A significant portion of approved drugs areeither natural products themselves or have a clear connection to aparent natural product.Withanolides (w.) constitute a group of natural C-28 steroidsisolated mainly from several genera of Solanaceae. They have anergostane-type skeleton, oxidation at C-1, C-22 and C-26 beingtheir common feature. Biogenetic transformations of w. canproduce highly modified compounds in both the steroid nucleusand side chain, including the formation of additional rings.Their chemistry, biological activity and occurrence have alreadybeen reviewed.As part of our investigations of the withanolides of JaborosaJuss. species, we herein report the isolation of a set of novel andknown withanolides from J. cabrerae. In addition five newderivatives were prepared using jaborosalactone 38 as precursor,and the antiproliferative activity of natural and semisyntheticderivatives was evaluated against a panel of representativehuman solid tumor cell lines.