C17H23NO3S, M(r) = 321.4, monoclinic, P2(1)/c, a = 8.724 (3), b = 12.009 (3), c = 15.780 (4) angstrom, beta = 91.81 (3)-degrees, V = 1652.4 (9) angstrom3, Z = 4, D(x) = 1.29 g CM-3, lambda(Mo Kalpha) = 0.71069 angstrom, mu = 2.08 cm-1, F(000) = 688, T = 291 K, R = 0.071 for 1671 observed reflections. In the four-membered ring the nitrogen substituent is exo; the ring is far from planar, with a dihedral angle about one diagonal of 32 (1)-degrees.