Emtricitabine Tenofovir Disoproxil Dimer

Emtricitabine Tenofovir Disoproxil Dimer is a structurally defined dimeric compound formed via a phosphodiester linkage between the 5'-hydroxyl group of Emtricitabine's furanose ring and the prodrug ester moiety of Tenofovir Disoproxil. The molecule incorporates a cytosine base, a β-D-ribofuranose ring, and a bis-propanediol phosphate ester, creating a stable, symmetrical dimeric architecture. This impurity arises during API synthesis through intermolecular coupling under esterification conditions. It serves as a critical HPLC reference standard for quantifying process-specific impurities in fixed-dose antiretroviral combinations.