STRUCTURE OF ISOPROPYL 2-CHLORO-5-(2-METHYL-1,4-OXATHIIN-3-YLCARBONYLAMINO)-BENZOATE, OXATHIIN CARBOXANILIDE

C16H18ClNO4S, M(r) = 355.8, monoclinic, P2(1)/a, a = 8.784 (1), b = 20.342 (1), c = 9.522 (1) angstrom, beta = 98.61 (1)-degrees, V = 1682.3 angstrom 3, Z = 4, D(x) = 1.404 g cm-3, lambda(Cu K-alpha) = 1.5418 angstrom, mu = 33.5 cm-1, F(000) = 744, T = 295 K, final R = 0.044 for 2156 observed reflections. The crystal structure and conformation are reported for this new potential AIDS drug whose mode of action differs from that of the dideoxynucleosides. The molecules are hydrogen bonded and form infinite chains along the a axis. The crystal packing leads to parallel stacking of the rings of the molecules.