[Development of nonsteroidal antiandrogens: 4-nitro-3-trifluoromethyldiphenylamines]

For the development of new nonsteroidal antiandrogens a series of 4-nitro-3-trifluoromethyldiphenylamines was synthesized and compounds were tested for their affinities to steroid hormone receptors and for antiandrogenic activities. These compounds were synthesized by reacting 4-nitro-3-trifluoromethylphenylsulfocyanamide-sodium (4) with the corresponding aromatic amines to give the N-(4-nitro-3-trifluoromethylphenylsulfonyl)-N'-phenylguanidines . The crude products were then converted to the desired diphenylamines by Smiles rearrangement and hydrolysis. 2-Hydroxy-4'-nitro-3'-trifluoromethyldiphenylamine (13), which shows a relative binding affinity (RBA) to the androgen receptor (AR) of 6.5% of that of testosterone, exerts a higher affinity than hydroxyflutamide (RBA = 4.5). Shift of the hydroxy-function to position 3 or 4 as well as N-methylation caused a decrease in AR-affinity. Compounds exerting AR-affinity were tested for antiandrogenic activity. Compound 13 showed the best antiandrogenic effect, though less than the well-known antiandrogen flutamide.