[{"from": "human", "value": "Could you provide a description of this molecule? [C][C@][C][C][C][=Branch1][C][=O][C][=Branch2][Ring1][=Branch2][=C][Ring1][#Branch1][C][C][C@@H1][C@@H1][Ring1][O][C][C][C@][Branch1][#Branch2][C@H1][Ring1][=Branch1][C][C][C][Ring1][Branch1][=O][C][O]"}, {"from": "gpt", "value": "The molecule is also a prohormone of 4-hydroxytestosterone, an active steroid with weak androgenic activity and mild aromatase inhibitor activity. It is listed as a prohibited substance by the World Anti-Doping Agency for use in athletes.    Formestane has poor oral bioavailability, and thus must be administered fortnightly (bi-weekly) by intramuscular injection. Some clinical data has suggested that the clinically recommended dose of 250mg was too low. With the discovery of newer, non-steroidal and steroidal, aromatase inhibitors which were orally active and less expensive than formestane, formestane lost popularity.   Currently, formestane (categorized as an anti-estrogenic agent) is prohibited from use in sports in accordance to the regulations of the World Anti-Doping Agency. It is not US FDA approved, and the intramuscular injection form of formestane (Lentaron) which was approved in Europe has been withdrawn."}]