NMR Analysis of a Series of 6,14-Ethenomorphinan Derivatives as PET Precursors and Reference Substances**

摘要

The new semisynthetic oripavine derivative 3-O-trityl-6-O-desmethyl-dihydroetorphine was synthesized from the poppy alkaloid thebaine in a six-step procedure. This compound can be applied as precursor for the radiosynthesis of [6-O-methyl-C-11]-dihydroetorphine ([C-11]DHE). We present a detailed description of H-1 and C-13 NMR data of reference standards and precursors for [6-O-methyl-C-11]- and [6-O-(2-[F-18]fluoroethyl]orvinols. This includes the complete assignment for 19 oripavine derivatives examined in 1D and 2D NMR experiments. We also investigated the molecular basis for regioselectivity of fluoroalkylation of 3-O-trityl-6-O-desmethyl-phenethyl-orvinol (TDPEO) using computational methods.