Long-chain 3-isopropyl alkanes: A new class of sedimentary acyclic hydrocarbons

摘要

Novel C_(27) and C_(29) 3-isopropyl alkanes have been unambiguously identified in sediments from the Kimmeridge Clay Formation through synthesis of a C_(29) standard. The covarying concentrations and similar stable carbon isotopic compositions of C_(21) and C_(23) n-alkanes, C_(25) and C_(27) iso alkanes, and C_(27) and C_(29) 3-isopropyl alkanes suggest a common, though unknown, biological source. It may be that these compounds are all products of an unknown biosynthetic process ultimately leading to the formation of isopropyl alkanes.