Convenient, Mild Catalytic Deprotection of Oximes to Carbonyl Compounds with Hydrogen Peroxide and Iodine Catalyst in Aqueous Acetonitrile
作者:Nemai C. Ganguly、Subhasis Nayek、Sujoy Kumar Barik
DOI:10.1080/00397910902883678
日期:2009.10.21
Abstract A clean, mild, and efficient catalytic deoximation procedure compatible with several common functional groups has been developed using 30% hydrogenperoxide activated by iodine catalyst in aqueous acetonitrile under essentially neutral conditions. The mechanistic features of an iodonium ion–driven nucleophilic cleavage of oximic C˭N have been revealed.
Structure−Activity Relationships of <i>N</i>-Hydroxyurea 5-Lipoxygenase Inhibitors
作者:Andrew O. Stewart、Pramila A. Bhatia、Jonathan G. Martin、James B. Summers、Karen E. Rodriques、Michael B. Martin、James H. Holms、Jimmie L. Moore、Richard A. Craig、Teodozyj Kolasa、James D. Ratajczyk、Hormoz Mazdiyasni、Francis A. J. Kerdesky、Shari L. DeNinno、Robert G. Maki、Jennifer B. Bouska、Patrick R. Young、Carmine Lanni、Randy L. Bell、George W. Carter、Clint D. W. Brooks
DOI:10.1021/jm9700474
日期:1997.6.1
The discovery of second generation N-hydroxyurea 5-lipoxygenase inhibitors was accomplished through the development of a broad structure-activity relationship (SAR) study. This study identified requirements for improving potency and also extending duration by limiting metabolism. Potency could be maintained by the incorporation of heterocyclic templates substituted with selected lipophilic substituents. Duration of inhibition after oral administration was optimized by identification of structural features in the proximity of the N-hydroxyurea which correlated to low in vitro glucuronidation rates. Furthermore, the rate of in vitro glucuronidation was shown to be stereoselective for certain analogs. (R)-N-[3-[5-(4-Fluorophenoxy)-2-furyl]-1-methyl-2-propynyl]-N-hy- droxyurea (17c) was identified and selected for clinical development.
Polysubstituted Indole Synthesis via Palladium/Norbornene Cooperative Catalysis of Oxime Esters
Polysubstituted indoles are prevalent in pharmaceuticals, agrochemicals, and organic materials. Presented herein is the fact that polyfunctionalized indoles can be efficiently constructed from easily accessible oxime esters and aryl iodides, involving a palladium/norbornene synergistic synthesis. The reaction is enabled by a unique class of electrophiles in palladium/norbornene cooperative catalysis