Structural multiplicity in a solvated hydrate of the anti­retroviral protease inhibitor Lopinavir

Abstract

The multi-component solvated Lopinavir crystal was prepared using evaporative methods. The crystal structure is unusual in that the unit cell contains 18 mol­ecules. The stoichiometric ratio of this crystal is eight Lopinavir mol­ecules, three ethane-1,2-diol mol­ecules and seven water mol­ecules.

Lopinavir is a potent protease inhibitor that is used as a first-line pharmaceutical drug for the treatment of HIV. The multi-component solvated Lopinavir crystal, systematic name (2S)-N-[(2S,4S,5S)-5-[2-(2,6-di­methyl­phen­oxy)acetamido]-4-hy­droxy-1,6-di­phenyl­hexan-2-yl]-3-methyl-2-(2-oxo-1,3-diazinan-1-yl)butanamide–ethane-1,2-diol–water (8/3/7) 8C₃₇H₄₈N₄O₅·3C₂H₆O₂·7H₂O, was prepared using evaporative methods. The crystalline material obtained from this experimental synthesis was characterized and elucidated by single-crystal X-ray diffraction (SC-XRD). The crystal structure is unusual in that the unit cell contains 18 mol­ecules. The stoichiometric ratio of this crystal is eight Lopinavir mol­ecules [8(C₃₇H₄₈N₄O₅)], three ethane-1,2-diol mol­ecules [3(C₂H₆O₂)] and seven water mol­ecules [7(H₂O)]. The crystal packing features both bi- and trifurcated hydrogen bonds between atoms.