STRUCTURE OF GALPHIMINE-B

xy-13alpha-methoxycarbonyl-30-nor-3,4-seco-7alpha, 18beta-fridela-1,20 -dien-3,24-olide methylene chloride solvate, C30H44O7.0.898CH2Cl2, M(r ) = 601.6, orthorhombic, P2(1)2(1)2(1), a = 9.797 (4), b = 15.039 (7), c = 20.135 (8) angstrom, V = 2966.5 (8) angstrom3, Z = 4, D(x) = 1.34 7 g cm-3, lambda(Cu Kalpha) = 1.54178 angstrom, mu = 23.66 cm-1, F(000 ) = 1288, T = 298 K, R = 0.062 for 2004 reflections with F > 3sigma(F) . In the pentacyclic molecule, rings C and D adopt a chair conformatio n while ring E shows a half-chair conformation (ring junctions: C/D, t rans; D/E, cis). The seven-membered ring A and six-membered ring B are considerably distorted (twist and -monoplanar conformations, respecti vely) which is reflected in the pseudo-trans A/B ring junction [torsio n angles -11.3 (3) and 1.3 (3)degrees] Intramolecular O(3)-H(3)...O(4) [D-H 1.04 (6), H...A 1.72 (6), D...A 2.720 (8) angstrom, D-H...A 160 (1)degrees] and intermolecular O(4)-H(4a)...O(3) (x - 0.5, 1.5 - y, 2 - z) [D-H 0.77 (7), H...A 2.26 (7), D...A 3.005 (8) angstrom, D-H...A 165 (1)degrees] hydrogen bonds stabilize the molecules in the crystal.