Solvent-free synthesis of some new 2-(3,5-dimethoxy-4-methylphenyl)-5-aryl-1,3,4-oxadiazoles

某新 2-(3,5-dimethoxy-4-methylphenyl ) 的迅速的加速微波的一步合成由有在在整洁的条件下面的 thionyl 的存在的不同羧酸的 3,5-dimethoxy-4-methyl 一种肺结核特效药的反应的 -5-aryl-1,3,4-oxadiazoles，被完成了。

SYNTHESIS OF DERIVATIVES OF 3-β-D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES

The synthesis of derivatives of 3-β-D-xylopyranosyl-1,2,4-oxadiazoles is accomplished by condensing protected β-D-xylopyranosyl amidoxime with acid anhydrides or various substituted benzoyl chlorides in good yield.The structures of now derivatives were identified by spectra and elemental analysis. The stability of 1,2,4-oxadiazole ring and mechanism of cyclization were. investigated.

Synthesis and Fungicidal Activities of 2-Alkylthio-5-(3,4,5-tribenzyloxyphenyl)-1,3,4-oxadiazoles

Abstract： Ten novel 2-alkylthio-5-（3, 4, 5-tribenzyloxyphenyl）-1, 3, 4-oxadiazole derivatives （5a-j） were synthesized from methyl 3, 4, 5-trihydroxybenzoate by ethedfication, hydrazidation, cyclization and thioetherification reactions. The structures of 5a-j were confirmed by 1HNMR, MS spectra and elemental analysis. The results indicated that most of the compounds 5 exhibited good fungicidal activities. The activity of 5h is higher than 90% against Fusarium oxysporum and Botrytis cinereapers in 50 mg/L.

A mild and facile method for one pot synthesis of 2,5-di-substituted 1,3,4-oxadiazoles at room temperature

2,5-Di-substituted 1,3,4-oxadiazoles 3a-n 从酸一种肺结核特效药 1 的反应作为一个壶过程被综合了，酰卤化物 2 并且在在房间温度的 acetonitrile 的磷 pentoxide。高产量，短反应时间(10 鈥 ? 5 min ) ，温和状况，和容易的病情的检查是这方法论的优点。

An expeditious and one-pot synthesis of unsymmetrical 2,5-disubstituted-1,3,4-oxadiazoles under microwave irradiation and solvent-free conditions

经由有 orthoesters 在下面的 benzoylhydrazines 的 cyclocondensation 的某不对称的 2,5-disubstituted-1,3,4-oxadiazoles 的一个壶合成没有溶剂并且微波条件这里被描述。当它在高收益和相对短的时间提供了标题混合物，反应被支持硅石的硫磺的酸高效地催化。催化剂是可重用的并且没有可观的减少，能在反应的收益和率若干次被使用。

One-pot synthesis,antibacterial and antifungal activities of novel 2,5-disubstituted-1,3,4-oxadiazoles

一系列新奇 2,5-disubstituted-1,3,4-oxadiazoles 从长链的 alkanoic 和 alkenoic 酸被综合了。这些混合物的结构被阐明了由元素、光谱(红外， 1H NMR， 13C NMR， MS ) 分析。而且，混合物被屏蔽为在对代表性的面板的 vitro 抗菌活性二克积极并且二个克否定的细菌。所有综合混合物也对真菌的五紧张为他们的抑制效应被测试。对测试有机体的各种各样的混合物表演有势力抑制效应。

微波促进下3-(2-苯并呋喃基)-4-氨基-5-巯基-1,2,4-三唑及其衍生物的合成

微波辐射条件下,首先由2-苯并呋喃甲酰肼依次与二硫化碳和水合肼反应合成3-(2-苯并呋喃基)-4-氨基-5-巯基-1,2,4-三唑,进一步在微波辐射条件下由4-氨基-5-巯基-1,2,4-三唑分别与芳甲酸/芳氧基乙酸、α-溴代苯乙酮及芳醛反应以较高产率制得了相应的1,2,4-三唑并[3,4-b]-1,3,4-噻二唑、1,2,4-三唑并[3,4-b]-1,3,4-噻二嗪及4-芳亚甲基亚胺基-5-巯基-1,2,4-三唑.产物结构经IR,1HNMR,MS及元素分析进行了表征.

1,3,4-[口恶]二唑类化合物的合成及生物活性研究进展

1,3,4-[口恶]二唑是一类重要的含氮五元芳香杂环类结构单元,可与多种药效团融合,产生不同的生物活性,因此引起了人们的关注,也显示了广泛的应用和发展前景,在医药和农药领域尤为突出。综述了国内外以酰肼环合法、Huisgen反应高效构建1,3,4-[口恶]二唑类化合物的方法,同时对1,3,4-[口恶]二唑类化合物在抗病毒、抗菌、抗肿瘤、除草、杀虫等方面的生物活性进行了介绍,并对各类化合物的构效关系进行总结,为进一步研究1,3,4-[口恶]二唑类化合物的设计合成及其生物活性提供参考和借鉴。

Synthesis of 5-Substituted-3-[(2’R,4’R)-4’-Hydroxy-2’-hydroxymethyltetrahydrofuran-4’-yl]-1,2,4-oxadiazoles and Their Epimers

The syntheses of 5-substituted-3-[( 2’ R, 4’ R)-4 ’ -hydroxy-2 ’ -hydroxymethyltetra-hydrofuran-4’ -yl]D-1 ,2, 4-oxadiazoles and their epimers were accomplished with the aid of th construction of 1,2, 4-oxadiazoles by condensation of O-acylated cyanohydrins with hydroxylamine via intramolecular transacylation and subsequent cyclization.

探索性有机化学实验教学——以2-氨基-5-乙基-1,3,4-噻二唑的合成为例

有机化学实验是制药工程专业重要的基础课之一,既是对有机化学理论课的补充,又是学习药学专业课的基础。本文以氨基硫脲和丙醛为原料,通过改变溶剂、氧化剂种类、反应温度、反应时间及反应物投料比筛选出最优反应条件,从而提高2-氨基-5-乙基-1,3,4-噻二唑的产率。通过本次实验,不仅有利于学生巩固理论知识,提高实验动手能力,培养学生热爱化学,热爱科研,激发探索性思维具有重要的作用。

2,5-二取代1,3,4-噻二唑的合成

以5-氨基-2-巯基-1,3,4-噻二唑为原料,经过胺基酰基化、氯气氧化制得5-乙酰胺基-1,3,4-噻二唑-2-磺酰氯,化合物与N-甲基哌嗪、苯胺反应,合成两个未见报道的目标产物:5-乙酰胺基-1,3,4-噻二唑-2-(N-甲基哌嗪磺酰胺)和5-乙酰胺基-1,3,4-噻二唑-2-(磺酰苯胺)。利用IR、H-NMR、LC-MS对目标产物进行表征。

1,3,4-oxadiazole-a bioactive scaffold for treating major depression-associated cognitive dysfunction

Background:Alzheimer’s disease affects millions of people worldwide,and one of its major characteristics is the accumulation of extracellular Aβpeptides in the human brain,leading to neuronal death and resulting in memory deficits,disorientation,and inappropriate behaviour.Objective and Methodology:This review study aims to develop new molecular targets for major depression-associated cognitive dysfunction and determine the mechanisms of action of 1,3,4-oxadiazole-based drug candidates.It encourages scientists to develop and synthesize drugs with low side effects to treat Alzheimer’s disease.Furthermore,the drug has shown significant improvement in memory function among dementia patients,which is due to the increased production of acetylcholine in the brain.These derivatives show a high affinity to amyloid plaques,which are thought to cause cognitive damage in patients with Alzheimer’s disease.This review study emphasizes newly developed inhibitors of amyloid deposition using the enzymeα-secretase,which cleaves amyloid precursor protein into smaller fragments that are toxic to neurons.1,3,4-Oxadiazole compounds have demonstrated no significant toxicity to the central nervous system.The antioxidant properties of 1,3,4-oxadiazoles can reduce free radicals,which play an active role in cell damage and disease.Conclusion:This review aims to provide readers with an overview of the current state of knowledge about oxadiazole-related drugs,emphasizing their biological importance.Key aspects related to the discovery and development of these drug candidates are discussed in detail,including information on their structure,biological activity,chemistry,and pharmacological properties.In addition,different derivatives discovered for Alzheimer’s disease to enhance the therapeutic efficiency of oxadiazole drugs have been comprehensively discussed in this review.

5-亚氨基-7-氧代-6-芳基偶氮-1,3,4-噻二唑[3,2-a]并嘧啶衍生物的绿色合成

合成了5种新的5-亚氨基-7-氧代-6-芳基偶氮-1,3,4-噻二唑[3,2-a]并嘧啶衍生物,通过元素分析、IR、1HNMR和质谱分析确定了其结构。

Synthesis and Crystal Structure of N-(2-(1,3,4-oxadiazol-2-yl)phenyl)-2,3-dimethylaniline

The title compound, N-（2-（1,3,4-oxadiazol-2-yl）phenyl）-2,3-dimethylaniline, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, ^1H- and ^13C-NMR spectroscopy, elemental analysis and mass spectrometry. These experimental studies were supported by theoretical optimizations.

2-取代硫醚-5-(5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶基)-1,3,4-噁二唑/噻二唑类化合物的合成及生物活性

以5-氨基-1H-1,2,4-三唑-3-羧酸乙酯为起始原料,设计合成了11个新型的2-取代硫醚-5-(5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶基)-1,3,4-噁二唑类化合物(5)和6个新型的2-取代硫醚-5-(5,7-二甲基-1,2,4-三唑并[1,5-a]嘧啶基)-1,3,4-噻二唑类化合物(8).通过1HNMR,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5k和8f的活性最好,在50mg/L浓度下对水稻纹枯病菌的抑制率达90%以上.

含有1H-1,2,4-三唑咪唑[2,1-b]-1,3,4-噻二唑、S-三唑[3,4-b]-1,3,4-噻二唑衍生物的合成及生物活性

合成了 1 8个含有 1 H-1 ,2 ,4-三唑的咪唑 [2 ,1 -b]-1 ,3 ,4-噻二唑以及 S-三唑 [3 ,4-b]-1 ,3 ,4-噻二唑的稠杂环衍生物 ,经元素分析及谱学表征 ,探讨 2 ,5 ,6-三取代咪唑 [2 ,1 -b]-1 ,3 ,4-噻二唑的可能生成机制 .对大肠杆菌、绿脓杆菌、枯草杆菌等初步抑菌试验证明 。

3,6-二取代苯基-二-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑衍生物的合成

以2,5-二巯基-1,3,4-噻二唑为原料,与水合肼缩合,生成2,5-二肼基-1,3,4-噻二唑.2,5-二肼基-1,3,4-噻二唑与苯甲酰氯反应生成2,5-二酰肼基-1,3,4-噻二唑,以POCl3为环合剂环合酰肼基-1,3,4-噻二唑,合成3,6-二取代苯基-二-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑衍生物,合成的新化合物的结构通过元素分析、红外光谱、核磁共振氢谱和质谱予以证实,并提出了环化反应机理.

Pharmacokinetic evaluation,molecular docking and in vitro biological evaluation of 1,3,4-oxadiazole derivatives as potent antioxidants and STAT3 inhibitors

1, 3, 4-Oxadiazole derivatives(4 a–5 f) were previously synthesized to investigate their anticancer properties.However, studies relating to their antioxidant potential and signal transducer and activator of transcription(STAT) inhibition have not been performed. We investigated previously synthesized 1, 3, 4-oxadiazole derivatives(4 a–5 f) for various radical scavenging properties using several in vitro antioxidant assays and also for direct inhibition of STAT3 through molecular docking. The data obtained from various antioxidant assays such as 2, 2,-diphenyl-1-picrylhydrazyl radical(DPPH), nitric oxide, hydrogen peroxide, and superoxide anion radical revealed that among all the derivatives, compound 5 e displayed high antioxidant activities than the standard antioxidant L-ascorbic acid. Additionally, the total reduction assay and antioxidant capacity assay further confirmed the antioxidant potential of compound 5 e. Furthermore, the molecular docking studies performed for all derivatives along with the standard inhibitor STX-0119 showed that binding energy released in direct binding with the SH2 domain of STAT3 was the highest for compound 5 e(-9.91 kcal/mol).Through virtual screening, compound 5 e was found to exhibit optimum competency in inhibiting STAT3 activity. Compound 5 e decreased the activation of STAT3 as observed with Western blot. In brief, compound5 e was identified as a potent antioxidant agent and STAT3 inhibitor and effective agent for cancer treatment.

2-氨基-5-取代-1,3,4-噻二唑与2-氯代-1-(2,4-二氯苯基)乙酮的反应研究

2 氨基 5 烷基 /芳基 1,3 ,4 噻二唑与 2 氯代 1 ( 2′ ,4′ 二氯苯基 )乙酮在热乙醇中反应生成一系列 2 烷基 /芳基 6 ( 4 ,4 二氯 )苯基咪唑并 [2 1 b] 1,3 ,4 噻二唑 .产物通过元素分析 ,IR ,1HNMR ,13 CNMR及MS分析 ,化合物 5g的X衍射晶体结构分析表明 ,产物的芳基是在咪唑并 [2 2 b] 1,3 ,4 噻二唑的 6 位而不在 5

新型1,2,4-三唑[3,4-b]-1,3,4-噻二嗪的合成及表征

以3-(2-苯基-1,2,3-三唑-4-基)-4-氨基-5-巯基-1,2,4-三唑(1)为原料分别与ω-溴代芳基乙酮、ω-溴代-ω-(1H-1,2,4-三唑-1-基)芳基乙酮反应,合成了一系列新的1,2,4-三唑[3,4-b]-1,3,4-噻二嗪类化合物2a～2e和3a～3e.其结构经IR,1HNMR和MS及元素分析确证.