Publications [#233515] of Andrew T. McPhail

Journal Articles

  1. Capps, TM; Hargrave, KD; Jeffs, PW; McPhail, AT, "Sceletium Alkaloids. Part 7. Structure and Absolute Stereochemistry of (-)-Mesembrane and 3'-Methoxy-4'-O-methyljoubertiamine, Two Minor Bases from S. Namaquense L. Bolus: X-Ray Analysis of (-)-Mesembrane Hydrochloride Monohydrate", J. Chem. Soc. Perkin II, 1977(8), 1098-1104, Royal Society of Chemistry (RSC) [Gateway.cgi], [doi].
    (last updated on 2026/01/21)

    Abstract:
    From S. namaquense L. Bolus, we have isolated the known base tortuosamine (7) and two new alkaloids, 3′methoxy-4′-O-methyljoubertiamine (6) and (–)-mesembrane (2) the structures of which have been established by spectroscopic and X-ray methods. Previous suggestions concerning the absolute configuration of alkaloids of the 3a-aryl-cis-octahydroindole ring system are confirmed by an X-ray analysis of (–)-mesembrane hydrochloride monohydrate which crystallizes in the monoclinic system, space group P21, with a= 14.50(1), b= 8.02(1), c= 7.57(1)Å, β= 93.4(1)°, Z= 2. The crystal structure was solved by direct methods and refined by least-squares calculations to R 0.055 over 1 158 reflections from diffractometer measurements. The absolute configuration was established by the anomalous dispersion effect. The c.d. spectrum of (–)-mesembrine, considered as an axial β-aminoketone, is shown to exhibit normal octant behaviour. © 1977 by The Chemical Society.