Reagents for Photoaffinity Labeling of Estrogen Binding Proteins. Synthesis of Some Azide and Diazo Derivatives of Estradiol, Estrone, and Hexestrol

Fourteen estrogen derivatives bearing a photosensitive functional group have been synthesized for use as photo-affinity labels for estrogen binding proteins: diazoacetate derivatives of 17β-estradiol and estrone, 16-diazoestrone, and 3-diazo-2-ketopropyl ether and ortho azide derivatives of estradiol, estrone, and hexestrol. All of these compounds are reasonably stable and easily purifiable. Attempts to introduce a diazo function at B-ring positions 6 and 7 of the estrogens have been unsuccessful: the 6-diazo derivative is thermally labile and the 6-keto-7-diazo derivative fails to form. This is presumably due to the hindrance at position 7, as the corresponding position (2) in 7-hydroxy-1-tetralone is easily functionalized.