Mirabegron S MIR II ortho Isomer

Mirabegron S MIR II ortho Isomer is a stereoisomeric impurity arising from the S-configured piperazine core of Mirabegron, featuring an ortho-substituted aromatic ring system relative to the parent compound’s para-substitution pattern. This isomer exhibits distinct regiochemistry in the phenolic moiety, altering intermolecular interactions while retaining the quinazoline-piperazine scaffold. It serves as a critical HPLC reference standard for quantifying positional isomer impurities in Mirabegron drug substance synthesis.