heterocycles due to their wide range of bioactivities. An efficient silver-catalyzed intermolecular cyclization of 2-aminopyridines with various alkynoates has been developed. 2-Substituted 4H-pyrido[1,2-a]pyrimidin-4-ones containing a wide range of functional groups are synthesized in the standard conditions. This transformation is conducted under convenient conditions and affords products in good yields
嘧啶酮由于其广泛的生物活性而成为重要的含氮杂环之一。已经开发了有效的银催化的2-氨基吡啶与各种链烷酸酯的分子间环化。在标准条件下合成含有2-官能取代的4 H-吡啶并[1,2 - a ]嘧啶-4-酮。该转化是在方便的条件下进行的,并以高收率提供产物。
Iodine-Catalyzed Regioselective Sulfenylation of 4H-Pyrido[1,2-a]pyrimidin-4-ones with Sulfonyl Hydrazides
作者:Shaohua Wang、Wenjie Liu、Zhihao Cai、Ziying Li、Jianwen Liu、Anda Wang
DOI:10.1055/s-0036-1588549
日期:2018.1
A simple and efficient method for direct sulfenylation of 4H-pyrido[1,2-a]pyrimidin-4-ones with sulfonyl hydrazides has been developed. The transformation is catalyzed by iodine under metal-free conditions with high regioselectivity and good functional-group tolerance.
Solvent-Free Synthesis of 4<i>H</i>-Pyrido[1,2-<i>a</i>]pyrimidin-4-ones Catalyzed by BiCl<sub>3</sub>: A Green Route to a Privileged Backbone
作者:Irwan I. Roslan、Qiu-Xuan Lim、Aijuan Han、Gaik-Khuan Chuah、Stephan Jaenicke
DOI:10.1002/ejoc.201500227
日期:2015.4
An extensive array of 4H-pyrido[1,2-a]pyrimidin-4-ones have been synthesized from commercially available 2-aminopyridines and β-oxo esters with excellent yields under solvent-free conditions. The reaction, catalyzed by cheap and nontoxic BiCl3, proceeds with short reaction times under mild conditions and normal atmosphere. Only water and alcohol are formed as co-products in this green reaction.
Synthesis of some substituted pyrido[1,2-<i>a</i>]pyrimidin-4-ones and 1,8-naphthyridines
作者:Pier Luigi Ferrarini、Claudio Mori、Oreste Livi、Giuliana Biagi、Anna Maria Marini
DOI:10.1002/jhet.5570200442
日期:1983.7
The substituted 4H-pyrido[1, 2-a]pyrimidin-4-ones (I) were obtained by the condensation of substituted 2-aminopyridines with δ-ketocarboxylic esters in PPA. Some of the derivatives I were transformed into the corresponding 1, 8-naphthyridines II and III.
通过将取代的2-氨基吡啶与δ-酮羧酸酯在PPA中缩合,得到取代的4 H-吡啶并[1,2 - a ]嘧啶-4-酮(I)。一些衍生物I被转化为相应的1、8-萘啶II和III。
Practical synthesis of 4H-pyrido[1, 2-a]pyrimidin-4-ones using ethylene glycol as a promoting solvent
作者:Mustafa Hussain、Jianhui Liu
DOI:10.1016/j.tetlet.2020.152269
日期:2020.9
A simple and useful protocol leading to different 4H-pyrido[1, 2-a] pyrimidin-4-ones have been established by cyclization of various 2-amino pyridines with β-oxo ester or alkynoate. The use of ethylene glycol was demonstrated to facilitate this condensation. This reaction proceeds by nontoxic, cheap, environment friendliness and biodegradable solvent at the normal green atmospheric condition in the