Crystal structures of five policyclic compounds related to the natural product forskolin

(3alphabeta(Z),4beta,6aalpha,9abeta,9bbeta)-(+/-)-3a,4,6a,7,8,9,9a,9b-octahydro-4,7,7,9b-tetramethyl-3a-[3-(methoxymethylocy)-3-methyl-l-butenyl]-5H-naphto[1,8-de]-1,3-dioxin-6-one (I), C22H36O5, M(r) = 378.51, monoclinic, P2(1)/n, a = 6.330(1), b = 14.576(2), c = 22.837(2) angstrom, beta = 93.04(1)-degrees, V = 2104.1(2) angstrom3, Z = 4, D(c) = 1.19 Mg/m3, lambda(MoKalpha) = 0.71069 angstrom, mu = 0.8 cm-1, F(000) = 832, T = 298 K, R = 0.054 for 1971 observed reflections; (7abeta, 10aalpha, 10bbeta, 12a)-(+/-)-7a9,10,10a,10b,11,12,12a-octahydro-2,2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopy-rano[4a,5,6,-de][1,32]-benzodioxin-11-one (II), C20H29O4, M(r) = 334.5, triclinic, P-1, a = 10.595(2), b = 12.152(1), c = 8.073(1) angstrom, alpha = 106.52(1), beta = 105.65(1), gamma = 66.29(1)-degrees, V = 897.9(2) angstrom3, Z = 2, D(c) = 1.24 Mg/m3, lambda(MoKalpha) = 0.71069 angstrom, mu = 0.8 cm-1, F(000) = 362, T = 298 K, R = 0.046 for 2848 observed reflections; (7abeta, 10aalpha, 10bbeta, 12alpha, 12aalpha)-(+/-)-7a,9,10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopy-rano[4a,5,6-de][1,3,2]-benzodioxin-11,12-diol (III), C20H32O5 (two molecules in the asymmetric unit), M(r) = 352.2, triclinic, P-1, a = 12.948(3), b = 13.615(3), c = 12.197(4) angstrom, alpha = 101.16(2), beta = 111.88(2), gamma = 69.48(2)-degrees, V = 1863.8(9) angstrom3, Z = 2, D(c) = 1.26 Mg/m3, lambda(MoKalpha) = 0.71069 angstrom, mu = 0.8 cm-1, F(000) = 768, T = 298 K, R = 0.060 for 4570 observed reflections; 4-acetoxy-4-[[(4abeta,5alpha,8abeta)-(+/-)-hexahydro-4a,6,6-trimethyl-4H-1,3-benzodioxin-4-one]-5-yl]butan-2-one (IV), C17H26O6, M(r) = 326.4, monoclinic, P2(1)/c, a = 10.495(2), b = 12.050(2), c = 14.216(2) angstrom, beta = 108.51(1)-degrees, V = 1704.8(5) angstrom3, Z = 4, D(c) = 1.27 Mg/m3, lambda(MoKalpha) = 0.71069 angstrom, mu = 0.9 cm-1, F(000) = 704, T =298 K, R = 0.049 for 2455 observed reflections; (3aalpha,4beta,5beta,6beta,6aalpha,9abeta,9bbeta)-(+/-)-4,5-epoxy-decahydro-3,3a-dihydroxy-2-ethoxy-4,7,7,9b-tetramethyl-naphto-[1,8-bc]-pyran-6-ol-acetate (V), C20H32O7, M(r) = 383.5, monoclinic, C2/c, a = 10.353(2), b = 17.975(3), c = 21.188(3) angstrom, beta = 91.29(1)-degrees, V = 3942(1) angstrom3, Z = 8, D(c) = 1.29 Mg/m3, lambda(MoKalpha) = 0.71069 angstrom, mu = 0.8 cm-1, F(000) = 1664, T =298 K, R = 0.051 for 2120 observed reflections. We report here the complete structures of four decalin derivatives (compounds I, II, III, V) and one related compound (compound IV) synthetized in order to find an efficient synthetic approach for the natural product forskolin.