S-Carvedilol

S-Carvedilol is the enantiomerically pure S-isomer of the non-selective beta-blocker Carvedilol, characterized by a chiral center at the alpha-carbon of its tertiary amine moiety. Its structure incorporates a 1-(4-(2-(o-methoxyphenoxy)ethyl)phenyl)-3-isopropyl-2-(o-nitrophenoxy)propan-2-amine scaffold, featuring a nitro group, methoxy substituent, and phenoxy ether linkage. This compound arises as a stereoisomeric impurity during the resolution of racemic Carvedilol via chiral chromatography or crystallization. It serves as an HPLC reference standard for enantiomeric purity quantification in API synthesis.