[{"from": "human", "value": "Provide a brief overview of this molecule. [C][S][=Branch1][C][=O][=Branch1][C][=O][O].[C][C][N][C][C][Branch2][Ring1][Ring2][C][=C][C][=Branch1][=C][=C][Branch1][#Branch2][C][=Branch1][=Branch1][=C][Ring1][=Branch1][Ring1][O][Cl][O][O][C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O]"}, {"from": "gpt", "value": "The molecule is the mesylate salt form of fenoldopam, a benzazepine derivative with rapid-acting vasodilator activity. Fenoldopam mesylate is a racemic mixture of S- and R- isomers; the latter is responsible for the biological activity and has a significantly higher affinity for dopamine D1-like receptors (D1 and D5) as well as moderate affinity to alpha-2 adrenergic receptors. This agent selectively activates the dopamine D1-like receptor, thereby causing vasodilatation and increasing renal perfusion."}]