De-A-lupane

As seen in Fig. 5.19, contributions from woody an-giosperms are likely to lead to the presence of oleanane in ancient sediments and oils, often accompanied by its ring-A degraded counterpart, 10P-de-A-oleanane.The ring-A degradation products of lupeol (10P-de-A-lupane) and OC-amyrin (10P-de-A-ursane) may also be present (Fig. 5.29 Woolhouse et al. 1992). 

Allemand P (1988) Contribution a f Etude de la Composition de Lichens Application de la Spectrometrie de Masse en Tandem (MS-MS) a f Identification de Triterpenes et Steroides. Thesis. Fac des Sciences, Univ Neuchatel Ammann W, Richarz R, Wirthlin T, Wendisch D (1982) H and C Chemical Shifts and Coupling Constants of Lupane. Org Magn Res 20 260 Anastasia M, Fiecchi A (1981) Synthesis of Lichesterol [Erogosta-5,8(9),22-trien-3P Ol]. J Chem Soc Perkin I 2125... 

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