Activity-Guided Isolation of an Antiandrogenic Compound of Pygeum africanum

Abstract

Inactivation of the androgen receptor (AR) through androgen ablation and treatment with antiandrogens is a major goal in the therapy for prostate hyperplasia and prostate cancer. Bioactivity-directed fractionation of a selective dichloromethane extract from the stem bark of Pygeum africanum led to the isolation of the antiandrogenic compound atraric acid. Its activity was examined by an androgen receptor responsive reporter gene assay. For lead structure optimization we transformed the natural occurring compound atraric acid into its ethyl, n-propyl and n-butyl esters and their antiandrogenic activities were examined as well. In addition, benzoic acid was isolated. The structures of all compounds were determined and characterized by means of ¹H- and ¹³C-NMR, HR-EI-mass, IR and UV spectroscopy.

Key words

Pygeum africanum - Prunus africana - Rosaceae - atraric acid - benzoic acid - antiandrogenic activity - androgen - hormone therapy

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