Here we report a novel non-nucleoside compound, PM-92131(+), with in vitro anti-HIV-1 activity. This product was synthesized as a pure enantiomer via diastereomeric ester formation and selective crystallisation and its absolute stereochemistry was determined by X-ray diffraction analysis. Results from the activity assays suggest PM-92131(+) could be a promising new compound for further assessment as a potential anti-HIV-1 agent.