Occurrence of two novel benzothiophene hopanoid families in sediments

Abstract

Two novel families of C34–C35 benzothiophene hopanoids have been identified in laminated marlstones and limestones of Hauptdolomit (Germany, Upper Triassic), Calcaires en Plaquettes (France, Upper Jurassic) and Ghareb (Jordan, Upper Cretaceous) Formations. Structures were assigned on the basis of Raney nickel desulphurization, deuteriated nickel boride desulphurization, mass spectral data and GC behaviour. Based on quantitative analysis, a precursor-product relationship between thiophene hopanoids and benzothiophene hopanoids seems likely. This means that the novel hopanoids are not formed by sulphur incorporation into benzohopanes, but instead cyclization and aromatization of the hopanoid side chain occur after sulphur incorporation.