Facile chelation-controlled reductive opening of methoxybenzylidene acetals with Bu3SnH and MgBr2. Regioselective protection strategy as MPM ethers
摘要:
A mild and efficient regioselective reductive opening of methoxybenzylidene acetals using a combination of Bu3SnH and MgBr2. OEt2, mainly via five-membered chelation intermediates is described. This reaction was applied to synthetic intermediates of myriaporon and tedanolide. (C) 2000 Elsevier Science Ltd. All rights reserved.
From solution to in-cell study of the chemical reactivity of acid sensitive functional groups: a rational approach towards improved cleavable linkers for biospecific endosomal release
作者:Sylvain A. Jacques、Geoffray Leriche、Michel Mosser、Marc Nothisen、Christian D. Muller、Jean-Serge Remy、Alain Wagner
DOI:10.1039/c6ob00846a
日期:——
panel of tested chemicalfunctionalities. Even within a structural family, a slight modification of the substitution pattern has an unsuspected outcome on the hydrolysis stability. This work led us to establish a first classification of these groups based on their reactivities at pH 5.5 and their relative hydrolysis at pH 5.5 vs. pH 7.4. From this classification, four representative chemical functions were
与生理pH相比,设计用于在酸性pH下进行选择性水解的pH敏感接头可用于在其作用部位选择性释放治疗剂。在本文中,研究了许多分子结构的水解裂解,据报道它们可用于pH敏感的递送系统。在经过测试的化学官能团中发现了各种各样的水解稳定性。即使在一个结构家族中,对取代模式的轻微修饰也会在水解稳定性方面产生意想不到的结果。这项工作使我们基于这些基团在pH 5.5时的反应性和在pH 5.5 vs. 5时的相对水解建立了这些基团的第一个分类。pH值7.4。从该分类中,选择了四个代表性的化学功能并进行了体外研究。结果表明,根据流式细胞仪测量,只有最活跃的功能才发生了明显的溶酶体裂解。这些最新结果质疑已知药物释放系统的基于酸的作用机理,并主张采用量身定制的方法进行深入的结构反应性研究对于合理设计和开发生物反应性接头的重要性。
Solid phase fluorescent labeling reagents (SPR) are described that simultaneously capture and label analytes, and then efficiently release the labeled-analytes under mild conditions (SCaLER).
redox center and a Lewis acid site of the pyridinium derivative, the first bifunctional small molecule photocatalyst has been developed for the one-pot tandem oxidation–acetalization reaction. A mechanism study reveals that pyridinium-mediated electron transfer and the photoactivation of molecular oxygen greatly facilitate the transformation of benzyl alcohols into the corresponding aldehydes, while
Bio-based glycerol and aldehydes have been valorised by acetalization reaction over novel macroporous sulfonated polystyrene-type resins (MR-SP20-SO3H and MR-SP50-SO3H). The influence of reactants molar ratio, catalyst amount, temperature, and reaction time on the activity and selectivity to acetals have been investigated. Results showed that MR-SP20-SO3H and MR-SP50-SO3H confirm a high performance
生物基甘油和醛已通过缩醛化反应在新型大孔磺化聚苯乙烯型树脂(MR-SP20-SO 3 H 和 MR-SP50-SO 3 H)上获得价值。研究了反应物摩尔比、催化剂用量、温度和反应时间对缩醛活性和选择性的影响。结果表明,MR-SP20-SO 3 H 和 MR-SP50-SO 3 H 证实了在甘油衍生物 1,2-丙二醇、1,3-丙二醇、3-甲氧基-1,2-丙二醇的缩醛化中的高性能和单醋精;这些催化系统可实现回收和再利用。