Disclosed are compounds of formula (I), prodrugs and salts thereof, and methods for their preparation. Specific examples of compounds of formula (I) include: 4-[(2S,3S)-2-ethyl-3-hydroxy-5-oxopyrrolidin-1-yl]-2-(trifluoromethyl)benzonitrile, 2-Chloro-4-[(4R,5S)-5-ethyl-3,3-difluoro-4-hydroxy-2-oxopyrrolidin-1-yl]benzonitrile, 4-[(2S,3S)-2-ethyl-3-hydroxy-5-oxopyrrolidin-1-yl]-2-(trifluoromethyl)benzonitrile, and 2-Chloro-4-[(2S,3S,4S)-2-ethyl-3-hydroxy-4-methyl-5-oxopyrrolidin-1-yl]benzonitrile. Also disclosed are pharmaceutical agents comprising compounds of formula (I) which act as tissue-selective androgen receptor modulators and agonists. These agents are useful for preventing or treating hypogonadism, male climacteric disorder, frailty, cachexia or osteoporosis and can also act as a frailty suppressant, a muscle strength enhancer, a muscle increasing agent, a cachexia suppressant, a body weight decrease suppressant, an agent for the prophylaxis or treatment of prostate hypertrophy, amyotrophy or muscle loss caused by a disease or an agent for reducing the prostate weight.
