Identification of 30- [2'-methylenethienyl] -hopane isomers in sediments

Two 30-[2'-methylenethienyl]-hopane isomers [based on the alpha-beta and beta beta configurations] have been identified in S-rich immature sediments from the Nordlinger Ries [southern Germany] in the aromatic hydrocarbon fractions separated from the total extractable lipids. The identification was used on chromatographic and mass spectral data and confirmed by carbon skeleton determination by desulfurization using Raney Ni. The results provide further evidence of the widespread occurrence of thienyl hopanes in immature sediments. These compounds are presumed to originate from the incorporation of sulfur into a C35 bactriohopanetetrol present in bacterial membranes during the early stages of diagenesis