Publications [#233538] of Andrew T. McPhail

Journal Articles

  1. McPhail, AT; Onan, KD, "Crystal and molecular structure of carolenalone, a cycloheptenone sesquiterpene lactone from north carolina Helenium autumnale L", Journal of the Chemical Society Perkin Transactions 2January,, 1976(3), 332-335, Royal Society of Chemistry (RSC) [Gateway.cgi], [doi].
    (last updated on 2026/01/21)

    Abstract:
    X-Ray single crystal analysis has established the structure and relative stereochemistry of the title compound (I). Crystals are orthorhombic, space group P212121, a = 7.31 (1), b = 21.20(1), c = 9.21 (1) Å, Z = 4. The structure was solved by direct methods and atomic positional and thermal parameters were refined by full-matrix least-squares calculations to R 0.078 over 476 reflections from diffractometer measurements. The cycloheptenone ring adopts a flattened twist-chair conformation in which the C:C·C:O system with a torsion angle of -157° is distinctly non-planar. The cyclopentane and γ-lactone rings are both in envelope conformations; the C(11) methyl group is β-oriented.