LANOSTANE SULFIDES IN AN IMMATURE CRUDE-OIL

Tetra-n-butylammonium periodate oxidation/LiAlH4 reduction, thiourea a dduction and molecular distillation were employed for the isolation of pentacyclic lanostane sulfides in an immature Chinese crude oil. The position of the sulfide bridges in the molecules was assigned by the d euterium exchange and mass spectra of the corresponding sulfones. Nick el boride desulfurization of the lanostane sulfides yielded C-30 and C -31 lanostanes, the structures of which were established by GC-MS with coinjection of synthetic standards. None of these lanostanes were fou nd to be present in the oil. (C) 1998 Elsevier Science Ltd. All rights reserved.