Maravirov MAI-III(Endo isomer)

Maravirov MAI-III (Endo isomer) is a stereoisomeric impurity arising from the bicyclic core of the parent antiretroviral Maravirov, characterized by a 1,4-dihydro-2H-3,1-benzoxazin-2-one scaffold with endo-oriented cyclohexane substituents. The compound retains the piperazine linker and N-methylpiperidine motif but exhibits altered stereochemistry at the cyclohexyl bridgehead, leading to reduced conformational flexibility. This impurity forms during oxidative coupling steps in the synthesis, resulting from non-optimized reaction kinetics. Functions as an HPLC reference standard for quantifying endo-isomer contamination in Maravirov drug substance batches.