Acta Cryst. (2007). E63, o3967 [ doi:10.1107/S1600536807042213 ]
Abstract: The title compound, C20H20ClNO3, belongs to a family of non-nucleoside reverse transcriptase inhibitors (NNRTI). It crystallizes with two independent molecules, A and B, in the asymmetric unit. In molecule A, the pyrrolidine ring is disordered between two positions with occupancies of 0.650 (2) and 0.350 (2), corresponding to two isomers, viz. 2R,4R and 2R,4S, respectively. The disorder of the pyrrolidine ring in molecule B [occupancies 0.512 (3) and 0.488 (3)] corresponds to the other two isomers, viz. 2S,4R and 2S,4S, respectively, showing that all four possible isomers are present in the crystal structure.
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