Stereospecific cis- and trans-ring fusions arising from common intermediates

Stereospecific cis- and trans-ring fusions arising from common intermediates.

Highly concise and stereospecific routes to cis and trans fusion, carrying various functionality at one of the bridgehead carbons, have been accomplished.

Bathorhodopsin intermediates from 11-cis-rhodopsin and 9-cis-rhodopsin.

Bathorhodopsin-rhodopsin difference spectra of native 11-cis-rhodopsin and regenerated 9-cis-rhodopsin were measured at room temperature with a double-beam laser spectrophotometer after excitation at 532 nm. A detailed analysis of data obtained at 85 psec after excitation suggests that the bathorhodopsins generated from 11-cis- and 9-cis-rhodopsin differ in their extinction coefficients and tha...

Stereospecific determination of cis- and trans-resveratrol in rat plasma by HPLC: application to pharmacokinetic studies.

A simple, accurate, precise, specific and reproducible high-performance liquid chromatography (HPLC) method was developed for simultaneous determination of resveratrol isomers in rat plasma. Cis-resveratrol was made by exposure of a trans-resveratrol solution to sunlight for 5 days followed by separation by HPLC and identification by mass spectrometry (MS). The assay procedure involved simple l...

Arising from the Tautological Ring

Stereospecific Synthesis of Substituted cis-Hydrindan-5-ones and Their Regiospecific Enolization and Functionalization: Synthetic Intermediates for Reserpine

An approach to reserpine (1) is described which is based on an anionic oxy-Cope rearrangement to establish three of the five contiguous asymmetric centers of the E ring and a regiospecific enol silylation coupled with hydroboration-oxidation to introduce the last two centers. The key intermediate 8b for the anionic oxy-Cope rearrangement is prepared from the readily available 7,7-dimethoxynorbo...