Iodine/persulfate-promoted site-selective direct thiolation of quinolones and uracils
摘要:
A simple and general method for direct thiolation of 4-quinolones with disulfides or thiols under I-2/K2S2O8 system has been developed. Under the optimal conditions, the C-S bond coupling can take place effectively with good to decent yields and excellent regioselectivity of the S-linked products. The established metal-free site-selective approach was also applicable to transform a range of uracil substrates to the thio-substituted products under mild conditions. Further transformation to the sulfone derivatives can be conveniently performed in one-pot. These easy-to-handle protocols represent a useful and interesting synthetic alternative with good substrate scope and functional group compatibility. (C) 2019 Elsevier Ltd. All rights reserved.
efficient iodide-catalyzed/hydrogen peroxide mediated sulfenylation and selenylation of unprotected uracil and its derivatives with simple thiols and diselenides was established. This coupling tolerates a broad variety of functional groups to provide diverse 5-sulfur/selenium-substituted uracilderivatives in good to excellent yields (up to 93%).
5-phenylthioacyclouridine: a potent and specific inhibitor of uridine phosphorylase
作者:Mahmoud H el Kouni、Naganna M Goudgaon、Mohammad Rafeeq、Omar N Al Safarjalani、Raymond F Schinazi、Fardos N.M Naguib
DOI:10.1016/s0006-2952(00)00410-x
日期:2000.9
synthesized as a highly specific and potent inhibitor of uridine phosphorylase (UrdPase, EC 2.4.2.3). PTAU has inhibition constant (K(is)) values of 248 and 353 nM towards UrdPase from mouse and human livers, respectively. PTAU was neither an inhibitor nor a substrate for thymidinephosphorylase (EC 2.4.2.4), uridine-cytidine kinase (EC 2. 7.1.48), thymidine kinase (EC 2.7.1.21), dihydrouracil dehydrogenase
A facile method was developed for the selective thioetherification of uracils using sulfonylhydrazide as the thioetherification reagent. This method offers advantages such as avoiding the use of additives and expensive metal catalysts, and providing good to excellent yields of various uracil thioethers. Experimental studies have demonstrated that the reaction follows a free radical pathway. Notably