(S)-(+)-cis-4′-Benzyloxypraziquantel

Abstract

The asymmetric unit of the title compound, C26H 30N2O3{systematic name (S)-(+)-2-[cis-4- (benzyloxy)cyclohexanecarbonyl]-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a] isoquinolin-4-one}, consists of two independent molecules in which the O= Camide group is syn to the N-C(C=Olactam) moiety, making dihedral angles of 2.0 (8) and 3.7 (8)°. The conformation of the 1,4-disubstituted cyclohexane ring is cis in each independent molecule, with the carbonyl group occupying an equatorial position and the benzyloxy group an axial position. In one molecule, two C and one O atom of the benzyloxy group are disordered over two sets of sites, with a refined occupancy ratio of 0.772 (8):0.228 (8). In the crystal, molecules are linked by C-H⋯O interactions, forming ribbons parallel to the b-axis direction.