The inhibitory effects of 13-epimeric estrones, D-secooxime and D-secoalcohol estrone compounds on human placental 17b-hydroxysteroid dehydrogenase type 1 isozyme (17b-HSD1) were investigated. The transformation of estrone to 17b-estradiol was studied by an in vitro radiosubstrate incubation method. 13a-Estrone inhibited the enzyme activity effectively with an IC 50 value of 1.2 mM, which indicates that enzyme affinity is similar to that of the natural estrone substrate. The 13b derivatives and the compounds bearing a 3-hydroxy group generally exerted stronger inhibition than the 13a and 3-ether counterparts. The 3-hydroxy13b-D-secoalcohol and the 3-hydroxy-13a-D-secooxime displayed an outstanding cofactor dependence, i.e. more efficient inhibition in the presence of NADH than NADPH. The 3-hydroxy13b-D-secooxime has an IC 50 value of 0.070 mM and is one of the most effective 17b-HSD1 inhibitors reported to date in the literature.
Abstract:The syntheses of C-13 epimeric 3-[(1-benzyl-1,2,3-triazol-4-yl)methoxy]-D-secoestrones are reported. Triazoles were prepared from 3-(prop-2-inyloxy)-D-secoalcohols and p-substituted benzyl azides via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The antiproliferative activities of the products and their precursors were determined in vitro against a panel of human adherent cervical (HeLa, SiHa and C33A), breast (MCF-7, MDA-MB-231, MDA-MB-361 and T47D) and ovarian (A2780) cell lines by means of MTT assays. The orientation of the angular methyl group and the substitution pattern of the benzyl group of the azide greatly influenced the cell growth-inhibitory potential of the compounds. The 13β derivatives generally proved to be more potent than their 13α counterparts. Introduction of a benzyltriazolylmethyl group onto the 3-OH position seemed to be advantageous. One 13α compound containing an unsubstituted benzyltriazolyl function displayed outstanding antiproliferative activities against three cell lines.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.