Crystal structure analysis of a new coumarin derivative

The title compound (6,6-dimethyl-cis-6H,6aH,7H,12bH,13H-bis[1] benzopyrano[ 4,3-b:4 ' ,3 ' -d]pyran-13-one) crystallizes in monoclinic space group P2(1 )/c with Z = 4. The unit cell dimensions are a = 8.6231(2) Angstrom, b = 10 .0260(2) Angstrom, c = 19.8376(2) Angstrom, and beta = 102.1(1)degrees, V = 1674.51(5) Angstrom (3), D-cal = 1.326 Mg/m(3). The coumarin moiety is in the planar conformation, the dioxadecalin moiety is cis fused and within th e dioxadecalin moiety both the rings are in half cahir/sofa conformations. The structure has many C-H...O type interactions.