论文信息 - The crystal and molecular structure of a mineral diterpene, bombiccite, C20H34

The crystal and molecular structure of a mineral diterpene, bombiccite, C20H34

A natural product found in lignite mines has been assigned the structure ofa-dihydrophyllocladene by crystal structure analysis. The crystals are triclinic, P1, a = 11.39 (7), b = 21.29 (5), c = 7.45 (1)/~,, tt = 94.6 (1), fl = 101.8 (2), y = 81.5 (1) ° and Z = 4. The structure has been solved by direct methods followed iteratively by Fourier syntheses and least-squares refinement of site occupation factors of the resulting peaks. The four independent molecules have the same configuration at the six chiral centres. Rings A, B and C assume the chair conformation with trans junctions, and ring D is an envelope. 1311

G. Sheldrick | A. Krajewski | L. R. Sanseverino | E. F. Serantoni | R. Mongiorgi

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[2] Ray Pepinsky,et al. Computing methods and the phase problem in X-ray crystal analysis : report of a conference held at the Pennsylvania State College, April 6-8, 1950 , 1952 .