吡啶并嘧啶类化合物的合成研究进展

综述了近二十年来吡啶并嘧啶类化合物的合成研究进展，介绍了三大类吡啶并嘧啶类化合物的主要结构类型：吡啶并[2,3-d]嘧啶类化合物、吡啶并[1,2-a]嘧啶类化合物、吡啶并[4,3-d]嘧啶类化合物的相关合成方法及新进展。     

新型环烷烯并嘧啶并噻唑-3-酮类化合物的合成

以环戊酮、环庚酮为起始原料合成的环烷烯并[1,2-d]嘧啶-2-硫酮(2)与氯乙酸、芳香醛反应, 合成具有潜在抗癌活性的稠合杂环化合物5-芳基-2,8-二芳亚甲基-2,3,6,7-四氢-5H,8H-环戊烯并[1,2-d]噻唑并[3,2-a]嘧啶-3-酮(3)以及5-芳基-2,10-二芳亚甲基-2,3,6,7,8,9-六氢-5H,10H-环庚烯并[1,2-d]噻唑并[3,2-a]嘧啶-3-酮(4). 3和4的结构经¹H NMR, IR, MS分析确认.     

KF-Al2O3催化下吡喃并[2,3-d]嘧啶衍生物的一步合成

以芳醛、丙二腈和4,6-二羟基嘧啶为原料, 以乙醇为溶剂, 在80 ℃以KF/Al₂O₃为催化剂合成了一系列的吡喃并[2,3-d]嘧啶衍生物, 产物的结构通过IR, ¹H NMR和元素分析表征, 并进一步通过X射线衍射分析确证.     

KF/Al2O3催化下吡啶并[2,3-d]嘧啶衍生物的三组分一步合成

以芳醛、丙二腈和2,6-二羟基-4-氨基嘧啶为原料, 在KF/Al₂O₃催化下以乙醇为溶剂, 在80 ℃三组分一步合成了一系列吡啶并[2,3-d]嘧啶衍生物, 有趣的是在空气氧化作用下进一步发生了芳构化作用. 和其它合成方法相比, 该方法具有反应条件温和、容易操作和产率较高等优点, 并通过IR, ¹H NMR和元素分析确证产物的结构.     

四氢苯并[4',5']噻吩并[3',2':5,6]吡啶并[4,3-d]嘧啶-4(3H)-酮的合成、晶体结构及杀菌活性

通过氮杂Wittig反应合成了一系列结构新颖的未见文献报道的取代四氢苯并[4',5']噻吩并[3',2':5,6]吡啶并[4,3-d]嘧啶-4(3H)-酮化合物6, 产物的结构通过核磁共振氢谱、质谱、红外光谱、元素分析的确证. 为进一步了解此类化合物的结构, 对化合物6c进行了X射线单晶衍射. 初步杀菌活性测定结果表明, 该类化合物具有较好的杀菌活性和选择性. 如6f在50 mg/L浓度时, 对黄瓜灰霉菌的抑制率为98%.     

5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶-2-甲酰腙类化合物的合成与生物活性

以5-氨基-1H-1,2,4-三唑-3-羧酸为起始原料, 设计合成了13个新型的5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶-2-甲酰腙类化合物, 通过¹H NMR, MS和元素分析对所合成的化合物进行了结构表征. 初步的生物活性测试结果表明, 所合成的化合物均表现出不同程度的除草及杀菌活性, 其中化合物4b, 4h和5m的活性较好, 在50 mg/L浓度下对水稻纹枯病菌的抑制率达90 %以上.     

非经典稠合噻吩: 噻吩并[3,4-c]噻吩研究进展

具有10π-电子的噻吩并[3,4-c]噻吩体系, 由于其非经典的电子结构, 引起了很大的兴趣. 本工作综述了噻吩并[3,4-c]噻吩的合成和化学性质研究进展.     

三组分“一锅煮”合成4,5-二氢吡唑并[1,5-a]嘧啶

以芳香醛、5-氨基-1H-吡唑和丙二腈为原料, 三组分“一锅煮”合成4,5-二氢吡唑并[1,5-a]嘧啶类化合物. 所有化合物均经IR, ¹H NMR和元素分析检测. 该法是一种操作简单, 产率较高的方法.     

嘧啶并嘧啶类化合物的合成研究进展

综述了近几十年来在医药和农药领域具有广泛用途的嘧啶并嘧啶类化合物的合成研究进展,介绍了三大类嘧啶并嘧啶类化合物的主要结构类型:嘧啶并[1,2-a]嘧啶类化合物、嘧啶并[4,5-d]嘧啶类化合物、嘧啶并[5,4-d]嘧啶类化合物的相关合成方法及新进展.     

2-甲硫基-7(5)-取代-3-吡唑并[1,5-a]嘧啶甲酸乙酯的区域选择性合成与2D NMR 研究

利用3-甲硫基-4-乙氧羰基-5-氨基-1H-吡唑分别与甲基/芳基烯胺酮反应, 合成了8种新的化合物2-甲硫基-7-取代-3-吡唑并[1,5-a]嘧啶甲酸乙酯(3a～3g)和2-甲硫基-5-甲基-3-吡唑并[1,5-a]嘧啶甲酸乙酯(4a). 化合物的结构均经元素分析, IR, ¹H NMR, MS所证实, 异构体3a和4a的结构进一步由¹³C NMR, HMQC和HMBC确认. 同时, 探讨了区域选择性合成吡唑并[1,5-a]嘧啶类化合物可能的反应机理, 并对部分化合物杀菌活性进行了测试.     

Studies on Thiazolopyridines. Part 1: Antimicrobial Activity of Some Novel Fluorinated Thiazolo[3,2-a]Pyridines and Thiazolo[2′,3′:1,6]Pyrido[2,3-d]Pyrimidines

Ternary condensation of aromatic aldehydes, malononitrile and thioglycolic acid (2:2:1 molar ratio) in ethanol/piperidine afforded the corresponding thiazolo[3,2-a]pyridines 1a-d . Thiazolo[2',3':1,6]pyrido[2,3-d]pyrimidine 4 was obtained by refluxing of compound 1a with acetic anhydride. Also, thiazolopyrido pyrimidine 6 was produced by refluxing of 1a with triethylorthoformate followed by treatment with hydrazine hydrate. Refluxing 1a with formic acid yielded the thiazolopyridopyrimidine 8 which on chlorination with thionyl chloride furnished the chloro derivative 9 . Finally, amino thiazolo[2',3':1,6]pyrido[2,3-d]pyrimidine 10 was obtained by treatment of 1a with formamide. The structures of these compounds were established on the basis of elemental analyses, IR, 1 H NMR, and mass spectral data. Also, the antimicrobial activity of some synthesized compounds is reported.     

MgO nanopowders catalyzed synthesis of pyrano[4,3-d]thiazolo[3,2-a]pyrimidine derivatives

A cubic phase of pure MgO nanopowders was prepared in an aqueous solution containing freshly squeezed orange juice with pulp and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared (FT-IR) spectroscopic techniques. The catalytic potential of MgO nanopowders was evaluated in preparation of pyrano[4,3-d]thiazolo[3,2-a]pyrimidine and chromeno[4,3-d]thiazolo[3,2-a]pyrimidines derivatives using the three simple methods including thermal, ultrasonic irradiation, and high-speed ball milling (HSBM) technique under solvent-free conditions. All products were successfully formed in high yields.     

Organobase-catalyzed one-pot three-component synthesis of novel pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine derivatives

Research on Chemical Intermediates - An efficient, simple and fast procedure has been developed for the synthesis of a novel types of pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine derivatives through...     

Synthesis and characterization of novel 5-allyl-6-{(benzo[d]thiazol-2-yl)methyl}-2-(alkylsulfanyl)oxopyrimidine derivatives

Russian Journal of General Chemistry - A series of novel S-DABO analogues bearing thiazolo[3,2-a]pyrimidine and pyrimido[2,1-b][1,3]thiazine has been developed starting from...     

The reactions of heterocyclic isothiocyanates bearing an ortho ester group with aminoalcohols

Heterocyclic isothiocyanates 1,5,9 , bearing an o-ester group were converted to thiourea derivatives 2a-c, 6a-b , and 10a-b , respectively, using β-aminoalcohols, and to the fused ring systems, e.g., thieno[3,2-d]pyrimidine 4a-b , pyrido[2,3-d]pyrimidine 8 , pteridine 11a , thiazolo[3,2-a]pyrido[2,3-d]pyrimidine 7a-b , and thiazolo[3,2-a]mieno[3,2-d]pyrirnidine 3a-c , derivatives.     

Synthesis and halogenation of propargyl pyrazolo-[3,4-d]pyrimidine thioether

The reaction of 4-imino-1-methyl-5-phenyl-6-propargylthio-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidine with halogens leads to the formation of (Z)-8-halomethylene-4-imino-1-methyl-5-phenyl-4,5,7,8-tetrahydro-1H-pyrazolo[4,3-e][1,3]thiazolo[3,2-a]pyrimidinium trihalide. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1085–1088, July, 2008.     

Condensed thienopyrimidines. IV. Synthesis and gastric antisecretory activity of 2,3-dihydro-5H-oxazolothienopyrimidine derivatives

2,3-Dihydro-5H-oxazolo[3,2-a]thieno[3,2-d]-(2a--d), [3,4-d]-(2e--h), and [2,3-d]pyrimidine derivatives (2i,j) were synthesized and evaluated for gastric antisecretory activity. These analogues (2) were prepared stepwise starting from formylthiophenecarbamates (4). The structure-activity relationships of these compounds are discussed.     

One-Pot Synthesis of Novel Spiro Pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine Derivatives

In a one-pot synthesis, 1′-methyl-2,3″-dioxo-5″-aryl-1,2,5a″,7″,8″,9a″-hexahydro-5″H,6″H-dispiro[indole-3,2′-pyrrolidine-3′,2″-pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine]-4′-carboxylic acid methyl ester was prepared via the sequential reaction of 4-aryl-octahydro-pyrano[2,3-d]pyrimidine-2-thione, dimethyl acetylenedicarboxylate (DMAD), and a mixture of isatin and sarcosine. All the novel spiro compounds, in moderate yields, were characterized thoroughly by infrared, NMR, mass spectromentry, and elemental analysis together with x-ray crystallographic analysis.     

Thiazolo(oxazolo)thieno[b]pyrimidines. Preparation from 2-allylthio(oxy)thieno[2,3-d]pyrimidines and hydrolysis

Heterocyclization of 5,6-disubstituted 2-allylthio(oxy)-4-oxothieno[2,3-d]pyrimidines by treatment with halogens affords thieno[3,2-e]thiazolo[3,2-a]pyrimidine iminium salts. Treatment of these salts with aqueous sodium acetate results in cleavage of the thiazoline ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 413–418, March, 1989.