One-Step Synthesis of Tetrazolo[1,5-a]pyrimidines by Cyclization Reaction of Dihydropyrimidine-2-thiones with Sodium Azide
摘要:
An novel, versatile and cost-effective approach for tetrazolo[1,5-a]pyrimidines and tetrazolo[1,5-a]quinazolines from cyclization reaction of dihydropyrimidinethiones with sodium azide in the presence of mercuric acetate is described. To compare this procedure with the conventional method, we carried out the cyclization reactions through direct functionalization of the pyrimidinethione core, which obtained from Biginelli 3,4-dihydropyrimidine-2-thiones or 4-aryl-7,7-dimethyl-5-oxo-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thiones.
Al(III) chloride catalyzed multi-component domino strategy: Synthesis of library of dihydrotetrazolo[1,5- a ]pyrimidines and tetrahydrotetrazolo[1,5- a ]quinazolinones
作者:Parteek Kour、Varun P. Singh、Brijmohan Khajuria、Tajinder Singh、Anil Kumar
DOI:10.1016/j.tetlet.2017.09.052
日期:2017.11
Tetrazolo[1,5-a]pyrimidines are well recognized and valuable scaffolds in drug discovery. In the current manuscript, we demonstrated AlCl3 catalyzed synthesis of series of dihydrotetrazolo[1,5-a]pyrimidines and tetrahydrotetrazolo[1,5-a]quinazolinones via a modified Biginelli type multi-component reaction of 5-aminotetrazole, aldehyde and diverse active methylene components such as acetophenone/al
Tetrazolo [1,5- a ]嘧啶是药物发现中公认的有价值的支架。在当前的手稿中,我们证明了AlCl 3通过5-氨基四唑,醛和多种多样的修饰的Biginelli型多组分反应,催化合成一系列二氢四唑并[1,5- a ]嘧啶和四氢四唑并[1,5- a ]喹唑啉酮。活性亚甲基组分,如苯乙酮/乙酰乙酸烷基酯/二甲酮。这提供了直接从容易获得的起始原料直接构建高度官能化的二氢四唑并[1,5- a ]嘧啶和四氢四唑并[1,5- a ]喹唑啉酮的有效途径。
Iodine Catalyzed One-Pot Multicomponent Synthesis of a Library of Compounds Containing Tetrazolo[1,5-<i>a</i>]pyrimidine Core
作者:Li-Yan Zeng、Chun Cai
DOI:10.1021/cc9000983
日期:2010.1.11
blocks with active methylene catalyzed by iodine were investigated in a multicomponentone-pot protocol. A series of 5,7-diaryl-4,7-dihydrotetrazolo[1,5-a]pyrimidines C and 5-methyl-7-aryl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-6-carboxylates D were obtained in moderate to good yields. Further exploration rapidly afforded various E in good to excellent yields; in addition, compound F was also obtained under
Sustainable design and novel synthesis of highly recyclable magnetic carbon containing aromatic sulfonic acid: Fe
<sub>3</sub>
O
<sub>4</sub>
@C/Ph—SO
<sub>3</sub>
H as green solid acid promoted regioselective synthesis of tetrazoloquinazolines
Fe3O4@meso-C immobilized with activated 4-aminobenzenesulfonic acid to achieve Fe3O4@C/Ph—SO3H. Structural, physico-chemical, and magnetic properties of synthesized Fe3O4@C/Ph—SO3H catalyst using various analyses such as FT-IR spectroscopy, TGA, XRD, SEM, TEM. EDX, and VSM were investigated. Fe3O4@C/Ph—SO3H was used as a stable and recoverable acid catalyst for regioselective three-component synthesis of
制备了封装在多孔碳壳中的绿色且稳定的磁性 Fe 3 O 4核。然后,合成的 Fe 3 O 4 @meso-C 表面固定有活化的 4-氨基苯磺酸以获得 Fe 3 O 4 @C/Ph-SO 3 H。合成 Fe 的结构、物理化学和磁性3 O 4 @C/Ph-SO 3 H 催化剂使用各种分析,如 FT-IR 光谱、TGA、XRD、SEM、TEM。研究了 EDX 和 VSM。Fe 3 O 4 @C/Ph—SO 3H 用作稳定且可回收的酸催化剂,用于在温和条件下区域选择性三组分合成四唑并喹唑啉。由于具有活性 SO 3 H 基团,该催化剂提供了一种一次性的绿色方案,在温和条件下反应,产率高,并且能够回收和再利用而不会显着降低活性。
An efficient, multicomponent, green protocol to access 4, 7-dihydrotetrazolo [1, 5-<i>a</i>] pyrimidines and 5,6,7,9-tetrahydrotetrazolo[5,1-<i>b</i>]quinazolin-8(4H)-ones using PEG-400 under microwave irradiation
carry out the synthesis of different dihydrotetrazolo[1,5-a]pyrimidines and tetrahydrotetrazolo[1,5-a]quinazolinones. This method has the advantage of green protocol, operational simplicity, high yields, recyclability of the solvent and involves isolation of the final product without column purification. The scope of this reaction tolerates with aromatic, heteroaromatic and alicyclic aldehydes. Graphical
A green and cost-effective protocol developed using covalently bonded sulfamic acid graphitic carbon nitride (g-C3N4/NHSO3H) for the synthesis of quinazoline derivatives using three-component condensation reaction of benzaldehyde, 2-aminotetrazole and dimedone. The XRD, TEM, SEM, EDX and FT-IR techniques were used to identify the physical and chemical properties of g-C3N4/NHSO3H. The -NHSO3H solid catalyst, was reused eight times without significant decrease in activity. This catalyst acts as a benign acid catalyst, a green protocol of a one-pot due to having significant advantages such as active sites containing SO3H groups, reacting under mild conditions with high efficiency as well as the ability to recover and reuse without decreasing activity. (C) 2019 Elsevier Ltd. All rights reserved.