PHOTOCHEMICALLY STABLE, NON-LEACHING SUNSCREENS FROM EPOXIDE-BASED SILANE COUPLING AGENTS AND UV ABSORBING CHROMOPHORES
申请人:ARIZONA BOARD OF REGENTS ON BEHALF OF THE UNIVERSITY OF ARIZONA
公开号:US20180333347A1
公开(公告)日:2018-11-22
UV absorbing monomers having one or more alkoxysilyl functional groups are produced through epoxide reaction chemistry. Sol-gel or emulsion polymerization of said UV absorbing monomers by themselves, or with alkoxysilane comonomers, affords nanoparticle sunscreens with reduced chemical exposure and improved photostability. Minimized leaching and decreased levels of photo-degradation were achieved with covalent incorporation to ensure isolation of the sunscreen chromophores and any photo-products from the skin.
Kinetics and Mechanism of the Addition of Nucleophiles to α,β-Unsaturated Thiol Esters
作者:Rosemarie F. Hartman、Seth D. Rose
DOI:10.1021/jo060191+
日期:2006.8.1
δ-unsaturated thiolester (crotonyl or sorboyl) have been prepared. These compounds are subject to nucleophilic attack at the CC conjugated to the thiolester carbonyl group. The kinetics of the reactions of these thiolesters with N-acetyl-l-cysteine (NAC), N-acetylcysteamine, and N2-acetyl-l-lysine (NAL) have been studied, and the thiol addition products have been identified. The reaction rates increased