[{"from": "human", "value": "Provide a description of this molecule. [C][C][C][C][=N][N][Branch2][Ring2][S][C][=C][Ring1][Branch1][N][=C][Branch1][=Branch1][N][C][Ring1][=Branch1][=O][C][=C][Branch2][Ring1][O][C][=C][C][=Branch1][Ring2][=C][Ring1][=Branch1][S][=Branch1][C][=O][=Branch1][C][=O][N][C][C][N][Branch1][Branch1][C][C][Ring1][=Branch1][C][O][C][C][C]"}, {"from": "gpt", "value": "The molecule is precisely via this mechanism why sildenafil was at first researched as a potential treatment for angina - or chest pain associated with inadequate blood flow to the heart - before being serendipitously indicated for treating erectile dysfunction in the late 1980s. Nevertheless, it is because of this mechanism that sildenafil is also indicated for treating pulmonary arterial hypertension but is also additionally notorious for interacting with various anti-anginal or anti-hypertensive agents to develop potentially rapid, excessive, and/or fatal hypotensive crises.  Regardless, sildenafil, among a variety of other similar or related PDE5 inhibitors, has become a common and effective treatment for erectile dysfunction and since its formal approval for medical use in the public in 1998, continues to see millions of prescriptions written for it internationally. Although the medication has historically been most popularly recognized as Pfizer's brand name Viagra, sildenafil is currently available generically and even as a non-prescription over the counter medication in some countries."}]