Structure−Activity Relationships of N-Hydroxyurea 5-Lipoxygenase Inhibitors
摘要:
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.
Regioselective Asymmetric Formal (3+2) Cycloadditions of Nitrone Ylides from Isatins and Enals
作者:Yu-Rong Chen、Gu Zhan、Wei Du、Ying-Chun Chen
DOI:10.1002/adsc.201600805
日期:2016.12.7
A highly regio‐, diastereo‐ and enantioselectiveformal (3+2) cycloadditionreaction of nitrone ylides from isatins and α,β‐unsaturated aldehydes was developed via iminium catalysis in the presence of an additional base, furnishing a spectrum of 1′‐hydroxy‐3,2′‐pyrrolidinylspirooxindole frameworks. Interestingly, the regioselectivity could be finely switched in the reactions between nitrone ylides and