A series of fused thiazolo[3,2-a]pyrimidines (7a–g, 8a–f, 11a–g and 12a,b) have been synthesized in good yields by reaction of fused 3,4-dihydropyrimidin-2(1H)-thiones (4a–g) with phenacyl bromides (5,6)/3-(2-bromoacetyl)coumarins (9,10) under conventional heating in acetic acid. Analytical and spectral studies as well as single crystal X-ray diffraction data on the representative compound 8e confirmed
Synthesis of fused thiazolo[3,2-a]pyrimidinones: N-aryl-2-chloroacetamides as doubly electrophilic building blocks
作者:Banothu Janardhan、Basavoju Srinivas、Bavantula Rajitha、Crooks Peter A.
DOI:10.1016/j.tetlet.2013.11.001
日期:2014.1
2-Chloro-N-phenylacetamide and N-(benzo[d]thiazol-2-yl)-2-chloroacetamide are doubly electrophilic building blocks for the formation of ring annulated thiazolo[3,2-a]pyrimidinone products. This syntheticroute involves formation of the title compound in acceptable product yields by the elimination of the by-product, aniline/2-aminobenzothiazole. Analytical and spectral studies, as well as single crystal
2-氯-N-苯基乙酰胺和N-(苯并[ d ]噻唑-2-基)-2-氯乙酰胺是形成环环化的噻唑并[3,2- a ]嘧啶酮产物的双亲电结构单元。该合成途径涉及通过消除副产物苯胺/ 2-氨基苯并噻唑而以可接受的产物收率形成标题化合物。对代表性化合物6c的分析和光谱研究以及单晶X射线数据证实了所有反应产物的结构。
Benzo[h]thiazolo[2,3-b]quinazolines by an efficient p-toluenesulfonic acid-catalyzed one-pot two-step tandem reaction
作者:B. Sakram、B. Sonyanaik、K. Ashok、S. Rambabu、S. K. Johnmiya
DOI:10.1007/s11164-015-2112-4
日期:2016.3
A highly efficient method has been developed for synthesis of 7,9-disubstituted-6,7-dihydro-5H-benzo[h]thiazolo[2,3-b]quinazolines via multicomponent one-pot two-step tandem reaction involving 1-tetralone, arylaldehydes, thiourea, and 4-chlorophenacyl bromide/(3-bromoacetyl)coumarin utilizing p-toluenesulfonic acid as catalyst in glacial acetic acid under reflux conditions. Analytically pure products are formed with excellent yield and short reaction time. All the synthesized compounds were confirmed by their spectral and elemental analyses.
Base-mediated one-pot synthesis of 3,4,5,6-tetrahydro-4-substituted benzo[<i>h</i>]quinazoline-2(1<i>H</i>)-thione derivatives and evaluation of their antioxidant activity
ABSTRACT One-pot three-component Beginelli-like reactions of a ketone 1, an aryl aldehyde 2, and thiourea 3 in the presence of sodium hydroxide are described. In this reaction, 3,4,5,6-tertrahydro-4-substituted quinazoline-2(1H)-thionederivatives 4a–h were obtained in good yields (73–85%). The compound 4a has been characterized by single crystal X-ray analysis. All the synthesized compounds 4a–h and