Here is comparing to Formestane
1: Eur J Med Chem. 2008 Sep;43(9):1865-77. Epub 2007 Dec 7.Click here to read Links
Evaluation of ursolic acid isolated from Ilex paraguariensis and derivatives on aromatase inhibition.
Gnoatto SC, Dassonville-Klimpt A, Da Nascimento S, Galéra P, Boumediene K, Gosmann G, Sonnet P, Moslemi S.
Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Ipiranga 2752, Porto Alegre 90610-000, RS, Brazil.
The inhibitory potency of 3-beta-3-hydroxy-urs-12-ene-28-oic acid extracted from Ilex paraguariensis, a plant used in South American population for a tea preparation known as maté, and its derivatives to inhibit aromatase activity was assessed and compared to a phytoestrogen apigenin and a steroidal aromatase inhibitor 4-hyroxyandrostenedione (4-OHA). Among all compounds tested only ursolic acid 1 showed an efficient and dose-dependent aromatase inhibition with IC50 value of 32 microM as did apigenin (IC50=10 microM), whereas IC50 value of 4-OHA was 0.8 microM. Our results show that the incorporation of a metallocene moiety into the 3-beta-3-hydroxy-urs-12-ene-28-oic acid derivatives decreases the aromatase inhibition. Moreover, comparison of the structure/inhibitory potency relationship of compounds indicates that the presence of cycle A and the configuration of C3-OH and C17-COOH seems to be more favourable to recognize the active site of aromatase and to block its activity.