Synthesis of C-6 fluoroandrogens: Evaluation of ligands for tumor receptor imaging
摘要:
Seven androgens, substituted with fluorine at C-6, were prepared as potential imaging agents for androgen receptor-positive prostate tumors and were evaluated in vitro in terms of their lipophilicity and their relative binding affinities (RBA, relative to R 1881 = 100) for the androgen receptor and for sex steroid binding protein. Introduction of a fluorine atom into the C-6 position of an androgen generally decreases binding affinity to the androgen receptor, except in the two cases: 6 alpha-fluoro-19-nor-testosterone (RBA = 41.6 versus 30.6 for the unsubstituted steroid) and 6 alpha-fluoro-19-nor-testosterone (RBA = 8.9 versus 6.6). Receptor binding of the C-6 fluoro-androgens is also stereospecific, showing higher binding affinities for the alpha-epimers compared to the corresponding beta-epimers (4:1-15:1). Binding affinity to sex steroid binding protein is the lowest with 19-nor-testosterone, which is also the least lipophilic androgen studied. Based on the binding properties of compounds in this series, 6 alpha-fluoro-19-nor-testosterone appears to have the most promise as a turner imaging agent.
Synthesis of C-6 fluoroandrogens: Evaluation of ligands for tumor receptor imaging
作者:Yearn Seong Choe、John A. Katzenellenbogen
DOI:10.1016/0039-128x(95)00009-f
日期:1995.5
Seven androgens, substituted with fluorine at C-6, were prepared as potential imaging agents for androgen receptor-positive prostate tumors and were evaluated in vitro in terms of their lipophilicity and their relative binding affinities (RBA, relative to R 1881 = 100) for the androgen receptor and for sex steroid binding protein. Introduction of a fluorine atom into the C-6 position of an androgen generally decreases binding affinity to the androgen receptor, except in the two cases: 6 alpha-fluoro-19-nor-testosterone (RBA = 41.6 versus 30.6 for the unsubstituted steroid) and 6 alpha-fluoro-19-nor-testosterone (RBA = 8.9 versus 6.6). Receptor binding of the C-6 fluoro-androgens is also stereospecific, showing higher binding affinities for the alpha-epimers compared to the corresponding beta-epimers (4:1-15:1). Binding affinity to sex steroid binding protein is the lowest with 19-nor-testosterone, which is also the least lipophilic androgen studied. Based on the binding properties of compounds in this series, 6 alpha-fluoro-19-nor-testosterone appears to have the most promise as a turner imaging agent.
Chavis,C.; Mousseron-Canet,M., Bulletin de la Societe Chimique de France, 1971, p. 632 - 637