Publications [#233552] of Andrew T. McPhail

Journal Articles

  1. McPhail, AT; Onan, KD; Gross, PM, "Structure and absolute configuration of plenolin: X-ray analysis of plenolin p-iodobenzoate", Journal of the Chemical Society Perkin Transactions 2January,, 1975(5), 487-492, Royal Society of Chemistry (RSC) [Gateway.cgi], [doi].
    (last updated on 2026/01/21)

    Abstract:
    The structure and absolute configuration of the cytotoxic pseudoguaianolide sesquiterpene lactone, plenolin (II), have been determined by X-ray analysis of the p-iodobenzoate derivative (III). Crystals of (III) are orthorhombic, space group P21212, with a = 9.29(1), b = 26.85(1), c = 8.45(1) Å, Z = 4. The structure was solved by the heavy-atom method and the atomic parameters refined by full-matrix least-squares calculations to R 0.041 over 1165 independent reflections from diffractometer measurements. The absolute configuration was established by the anomalous dispersion effect. The cycloheptane ring adopts a twist chair conformation, the γ-lactone ring is in an envelope conformation, and the cyclopentenone ring approximates a half-chair form.