Visible-Light-Mediated, Diastereoselective Epimerization of Exocyclic Amines.

Stereoselective α-amino C-H epimerization of exocyclic amines is achieved via photoredox catalyzed, thiyl-radical mediated, reversible hydrogen atom transfer to provide thermodynamically controlled anti/syn isomer ratios. The method is applicable to different substituents and substitution patterns about aminocyclopentanes, aminocyclohexanes, and a -Boc-3-aminopiperidine. The method also provided efficient epimerization for primary, alkyl and (hetero)aryl secondary, and tertiary exocyclic amines.

Visible Light-Mediated, Diastereoselective Epimerization of Morpholines and Piperazines to More Stable Isomers.

We report a photocatalyzed epimerization of morpholines and piperazines that proceeds by reversible hydrogen atom transfer (HAT) and provides an efficient strategy for editing the stereochemical configurations of these saturated nitrogen heterocycles, which are prevalent in drugs. The more stable morpholine and piperazine isomers are obtained from the more synthetically accessible but less stable stereoisomers, and a broad scope is demonstrated in terms of substitution patterns and functional group compatibility. The observed distributions of diastereomers correlate well with the relative energies of the diastereomer pairs as determined by density functional theory (DFT) calculations.

Drug therapy and adverse drug reactions to terbutaline in obstetric patients: a prospective cohort study in hospitalized women.

BACKGROUND: Adverse drug reactions (ADR's) could be expected more frequently in pregnant women. This study was performed in order to identify ADR's to tocolytic drugs in hospitalised pregnant women. METHODS: A prospective cohort study was performed in two General Hospitals of the Instituto Mexicano del Seguro Social (IMSS) in Mexico City.