2-(ω-联苯基多亚甲基)-5-联苯基-1,3,4-二唑的荧光光谱研究

本文测定了双荧光团化合物2-(ω-联苯基多亚甲基)-5-联苯基-1,3,4-二唑及其模型化合物2-甲基-5-联苯基-1,3,4-二唑和2,5-二联苯基-1,3,4-二唑的荧光光谱.对分子内,分子间激基缔合物和激基复合物的形成进行了研究,并对分子构型与形成分子内激基复合物之间关系作了初步探讨.从实验结果得到,亚甲基桥链的碳数为奇数时容易形成分子内激基复合物.     

激基缔合物和激基复合物的形成及溶剂效应的研究

测试了ω-对联苯基多亚甲基羧酸4-[5′-对联苯基-1,3,4-(口恶)二唑基-2′-]苄酯及其模型化合物2-对甲苯基-5-联苯基-1,3,4-,(口恶)二唑在不同极性溶剂中的荧光发射光谱。它们既能形成分子间的激基缔合物又能形成分子内的激基复合物和三分子激基复合物。实验结果表明,溶剂极性的增加,有利于分子内激基复合物和三分子激基复合物的形成。     

含氮亲核试剂在2-甲磺酰基-5-(3,4,5-三甲氧基苯基)-1,3,4-恶二唑环上取代反应的研究

本文报道了制备2-甲磺酰基-5-(3,4,5-三甲氧基苯基)-1,3,4-恶二唑和其进一步与多种亲核试剂反应. 2-巯基-5-(3,4,5-三甲氧基苯基)-1,3,4-恶二唑经过甲基化, 而后用KMnO~4氧化得到2-甲磺酰基-5-(3,4,5-三甲氧基苯基)-1,3,4-恶二唑衍生物. 其结构由元素分析,IR, ^1H NMR 和MS确定.化合物4对大肠杆菌和枯草芽孢杆菌有较强的抑制性能.     

2-Phenyl-5-(4-Biphenylyl)-1,3,4-Oxadiazole and 2-(4'-tert-Butylphenyl-5)-(4'biphenylyl)-1,3,4-Oxadiazole in a Polymethyl Methacrylate Based Plastic Scintillator

The fluorescence intensity was studied for the scintillation formulation including 1,1,3-trimethyl-3-phenylindan and 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole, 2-(4'-tert-butylphenyl-5-(4"-biphenylyl)-1,3,4-oxadiazole, and 1,4-di(5-phenyl-2-oxazolyl)benzene. The scintillation efficiency was determined for the polymethyl methacrylate based plastic scintillator containing the above-listed compounds as luminescent additives.     

2-芳氧基-5-苯基-1,3,4-噁二唑类化合物的合成

本文通过芳氧基负离子在2—甲磺酰基—苯基—1,3,4—噁二唑环2—位上的亲核取代反应制得9个新的2—芳氧基—5—苯基—l,3,4—噁二唑衍生物。所有化合物的结构经元素分析,IR,~1H NMR和MS确认。初步抗菌实验表明这些化合物具有一定的抑制枯草芽孢杆菌繁殖的活性。 2,5—二取代l,3,4—噁二唑衍生物具有广泛的生物活性,如抗菌,抗黄球菌,除草杀棉花牙虫等。Madhavan等曾通过芳胺在2— 甲磺酰基—5—芳基1,3,4—噁二唑环上的亲核取代反应,制得了2—芳氨基—5—芳基—l,3,4—噁二唑衍生物,我们也曾通过酰肼等亲核试剂在2—甲磺酰基—5—(3,4,5—三甲氧基苯基)—1,3,4—噁二唑环上的亲核取代反应,得到了2—取代酰肼基—5—(3,4,5—三甲氧基苯基)—l,3,4—噁二唑衍生物。在此基础上,我们拟通过Aro在2—甲磺酰基     

2-Phenyl-5-(trichloromethyl)-1,3,4-oxadiazoles,A new class of antimalarial substances

An investigation of hybrids of 2,5-dimethyl-1,3,4-oxadiazole (I) and α,α,α,α',α',α'-hexachloro-p-xylene (Hetol®) (II) as potential antimalarial agents led to the synthesis of representative 2-phenyI-5-(trichloromethyl)-1,3,4-oxadiazoles (VIa-f, VIII-X) and related trichloromethyl 1,2,4-oxadiazole, 1,3,4-oxadiazoles, and 1,3,4-thiadiazole (VII, XIII-XV). Treatment of the appropriately substituted benzoic: acid hydrazides (IVa-f) with trichloroacetic anhydride afforded the intermediate 1-benzoyl-2-(triehloroacetyl)hydrazines (Va-f) which were cyclized to the desired 5-(chlorophenyl, tolyl, or α,α,α-trifluorotolyl)-2-(trichloromethyl)-1,3,4-oxadiazoles (VIa-f) (44–66%) in situ utilizing phosphorous oxychloride. Chlorination of the 5-tolyl-2-(trichloromethyl)-1,3,4-oxadiazoles (VId-f) afforded 2-(trichloromethyl)-5-(α,α,α-trichloro-m- and p-tolyl)-1,3,4-oxadiazole (VIII and IX) and 2-(α,α,α,α',α',α'-hexachloro-3,5-xylyl)-5-(trichloromethyl)-1,3,4-oxadiazole (X) in 23–56% yield. Each of the 2-phenyl-5-(trichloromethyl)-1,3,4-oxadiazoles (VIa-f, VIII-X) was active against Plasmodium berghei in mice when administered in single 160 or 640 mg./kg. subcutaneous doses or given orally by drug-diet for 6 days at doses of 29–336 mg./kg./day. The 2-(trichloromethyl)-5-(α,α,α-trichlorotolyl)-1,3,4-oxadiazoles (VIII-X) were the most active compounds prepared and exhibited activity against P. berghei comparable with Hetol®. Structure-activity relationships are discussed.     

Synthesis and antioxidant properties of organosulfur and organoselenium compounds derived from 5-substituted-1,3,4-oxadiazole/thiadiazole-2-thiols

Organosulfur and organoselenium compounds were synthesized in good yields through reaction with 5-aryl-1,3,4-oxadiazole/thiadiazole-2-thiols and α-chloromethyl arylselenides or 4-(chloromethyl)-2-methylthiazole/2-(chloromethyl)-5-phenyl-1,3,4-oxadiazole. The obtained compounds were characterized by NMR and mass spectroscopy and screened for in vitro antioxidant activity as reflected by free radical scavenging against 2,2-diphenyl-2-picrylhydrazyl (DPPH) and reduction of molybdenum (VI) to molybdenum (V). The compounds have significant antioxidant properties in both applied methodologies.     

Synthesis,characterization and anticancer evaluation of 2-(naphthalen-1-ylmethyl/naphthalen-2-yloxymethyl)-1-[5-(substituted phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-1H-benzimidazole

In the present study o-phenylenediamine and naphtene-1-acetic acid/2-naphthoxyacetic acid were used as a starting material through a series of steps and 2-(naphthalen-1-ylmethyl/Naphthalen-2-yloxymethyl)-1H-benzimidazol-1-yl]acetohydrazide 5a, 5b were obtained. In the first series 1,3,4-oxadiazole derivatives have been synthesized from Schiff base of the corresponding hydrazide i.e. 2-[2-(naphthalen-1-ylmethyl)-1H-benzimidazol-1-yl]acetohydrazide 5a by using Chloramin-T. In the second series 1,3,4-oxadiazole has been synthesized from 2-{2-[(naphthalen-2-yloxy)methyl]-1Hbenzimidazol-1-yl}acetohydrazide 5b by using phosphorous oxychloride and aromatic acid. These compounds were evaluated by IR, NMR, Mass spectrometry, elemental analysis and finally in vitro anticancer evaluation was carried out by NCI 60 Cell screen at a single high dose (10–5 M) on various panel/cell lines. One compound 7c was found to be the most active on breast cancer cell line and compounds 4b and 7d were moderately active.     

Synthesis of arylethylene derivatives of 2, 5-diphenyl-1, 3, 4-oxadiazole

The synthesis of arylethylene derivatives of 2,5-diphenyl-1,3,4-oxadiazole by the Wittig reaction from 2-(p-bromomethylphenyl)-5-phenyl-1,3,4-oxadiazole and aromatic aldehydes is described. The compounds obtained fluoresce strongly on irradiation with UV light.     

Synthesis and in vitro antibacterial activity of new oxoethylthio-1,3,4-oxadiazole derivatives

In the present investigation, a series of 2(4-pyridyl)-5[(aryl/heteroarylamino)-1-oxoethyl]thio-1,3,4-oxadiazole were synthesized using isonicotinohydrazide and substituted aryl/heteroaryl amines using pyridine as solvent. Newly synthesized compounds were tested for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system. Among the synthesized compounds, compounds 2(4-pyridyl)-5((2-nitrophenylamino)-1-oxoethyl)thio-1,3,4-oxadiazole (5e), 2(4-pyridyl)-5((4-nitrophenylamino)-1-oxoethyl)thio-1,3,4-oxadiazole (5g) and 2(4-pyridyl)-5((2-pyrrolylamino)-1-oxoethyl)thio-1,3,4-oxadiazole (5k) produced highest efficacy and exhibited >90% inhibition at a concentration of 0.0077, 0.0052 and 0.0089 μM, respectively. All the new compounds were pharmacologically evaluated for their in vitro Antimicrobial activity.     

Design and synthesis of oxaprozin-1,3,4-oxadiazole hybrids as potential anticancer and antibacterial agents

In the present study, we report design, synthesis and screening of new novel 5-substituted-2-mercapto-1,3,4-oxadiazole analogues appended to oxaprozin for their in vitro anticancer and antibacterial activity. The synthesised compounds were characterized using various spectroscopic techniques. Furthermore, the structure of 5b (2-(2-[4,5-diphenyloxazol-2-yl]ethyl)-5-(ethylthio)-1,3,4-oxadiazole) was unequivocally confirmed by X-ray analysis. Among the series 5c (2-(2-[4,5-diphenyloxazol-2-yl]ethyl)-5-(propylthio)-1,3,4-oxadiazole) showed most promising anticancer activity against A549 cancer cell line and all the reported analogues manifested satisfactory safety profiles against human normal cell line HEK293T. The products exhibited good antibacterial activity and among the tested 5j (2-(2-[4,5-diphenyloxazol-2-yl]ethyl)-5-([4-fluorobenzyl]thio)-1,3,4-oxadiazole) exhibited most potent.     

Synthesis and in-vitro antioxidant activities of some coumarin derivatives containing 1,2,3-triazole ring

A new green protocol was developed for the S-alkylation of 2-mercapto-1,3,4-oxadiazole by the reaction of 5-substituted-2-mercapto-1,3,4-oxadiazole with propargyl bromide in sodium bicarbonate in water. The newly synthesized 5-[(substitutedphenoxy)methyl]-2-[(prop-2-yn-1-yl)sulfanyl]-1,3,4-oxadiazole when reacted with azidomethyl coumarins underwent regioselective reaction yielding 4-(((4-((5-((substitutedphenoxy)methyl)-1,3,4-oxadiazol-2-yl)sulfanylmethyl)-1H-1,2,3-triazol-1-yl)methyl)-6-methyl)-2H-chromene-2-one or 1-((4-((5-((substitutedphenoxy)methyl)-1,3,4-oxadiazol-2-yl)sulfanylmethy)-1H-1,2,3-triazol-1-yl-)methyl)-3H-benzo[f]chromene-3-one. Structures of the newly synthesized compounds were confirmed by spectral and analytical data. The compounds were screened for their in-vitro antioxidant property.     

Ethynyl pi-extended 2,5-diphenyl-1,3,4-oxadiazoles and 2-phenyl 5-(2-thienyl)-1,3,4-oxadiazoles: synthesis, X-ray crystal structures and optical properties

2-(4-tert-Butylphenyl)-5-(4-ethynylphenyl)-1,3,4-oxadiazole reacts with a series of heteroaryl iodides under standard Sonogashira cross-coupling conditions (Pd[PPh(3)](2)Cl(2), CuI, triethylamine, THF) to yield products 2a-g in 40-79% yields (heteroaryl = 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrazyl, 5-bromo-2-pyrimidyl, 2-thienyl and 3-thienyl, respectively). Compound 2f was lithiated followed by electrophilic iodination (BuLi, perfluorohexyl iodide) to give 3, which by a two-step sequence gave the terminal ethynylthienyl derivative 5. Conversion of 5 into the terminal ethynylaldehyde derivative 7, via acetal derivative 6, proceeded in high yield. Starting from 2-iodo-5-methoxycarbonylthiophene, a five-step sequence afforded 2-(4-tert-butylphenyl)-5-(4-ethynylthienyl)-1,3,4-oxadiazole 13 (13% overall yield). Reactions of 13 gave terminal pyridyl, pyrazyl, pyrimidyl and thienyl derivatives, analogous to those obtained from 1. Two-fold reaction of 13 with 2,5-diiodothiophene gave the bis(ethynylthienyl)thiophene derivative 15 (30% yield). Solution UV-Vis absorption and photoluminescence spectra establish that replacement of the phenyl ring in the 2,5-diphenyl-1,3,4-oxadiazole series 2a-g by a thienyl ring [i.e. the 2-phenyl-5-(2-thienyl)-1,3,4-oxadiazole series 14a-g] leads to a red shift in the lowest energy band in both the absorption spectra and emission spectra. The X-ray crystal structures of compounds 2d, 2g, 5 and 14d.CHCl(3) reveal that the molecular structures are approximately planar although there are substantial differences in the conformations.     

2-芳氧基-5-苯基-1,3,4-恶二唑类化合物的合成

通过芳氧基负离子在2-甲磺酰基-5-1,3,4-恶二唑上的亲核取代反应制得2-芳氧基-5-苯基-1,3,4-恶二唑.所有化合物的结构经元素分析,IR, ^1H NMR和MS确证.这些化合物表现出一定的抑制枯草芽孢杆菌繁殖的活性.     

Synthesis and bioactivities of novel 2-(thioether/sulfone)-5-pyrazolyl-1,3,4-oxadiazole derivatives

By introducing the pyrazole moiety into the 5-position of 1,3,4-oxadiazole,a series of novel 2-(thioether/sulfone)-5-pyrazolyl-l,3,4-oxadiazole derivatives were synthesized.Preliminary bioassays suggested that target compounds exhibited appreciable activity against pathogenic bacteria Xanthomonas oryzae pv.oryzae(Xoo) and five phytopathogenic fungi in vitro.Among them,the half-maximal effective concentration(EC_(50)) values of 6c,7a,7b and 7c against Xoo were within 16.6 μg/mL and 65.7 μg/mL,which were better than those of commercial agricultural antibacterial bismerthiazol(92.6 μg/mL) and thiodiazole copper(121.8 μg/mL).While compounds 7a,7b,and 7c exerted comprehensive antifungal activity toward five plant fungi,which were comparable with that of hymexazol.The results demonstrated that this kind of compounds can be further studied and developed as promising antifungal and antibacterial agents.     

The synthesis and structure of a new type of aromatic heterocyclic macrocycle. IV. Synthesis of a 1,3,4-oxadiazole-containing azomacrocycle

A novel azomacrocycle containing the 1,3,4-oxadiazole ring has been prepared from 2,5-bis[3-(4-hydroxyphenylazo)phenyl]-1,3,4-oxadiazole 5 and 2,5-bis(2-chloromethlylphenyl)-1,3,4-oxadiazole 8 . The coupling reaction between the diazonium salt 4 and bisphenol A has been reported.     

Derivatives of 4-amino-4H-1,2,4-triazole-3-thiols linked to the pyrrole cycle and some products of their S-alkylation

This study offers an access to 21 new heterocyclic compounds representing pyrrole derivatives of 4-amino-4H-1,2,4-triazole-3-thiols or 1,3,4-oxadiazole-2-thiols. The principal synthetic approach is based on the cyclization of substituted potassium 2-(pyrrolecarbonyl)hydrazine-1-carbodithionate with hydrazine hydrate to 5-(substituted pyrrolyl)-4-amino-4H-1,2,4-triazole-3-thiols, followed by S-alkylation with methyl iodide or benzyl chloride. Among the resulted thirteen S-alkyl derivatives, five 1,3,4-oxadiazole derivatives have been isolated as secondary products and their formation is explained as being the result of S-alkylation of intermediate 1,3,4-oxa-diazole-2-thiols, generated in the alkaline medium. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 383–391, March, 2007.     

N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)酰胺类新化合物的合成及生物活性

以N-吡啶基吡唑甲酸和2-氨基-3-甲基苯甲酸为起始原料,经由亲核加成、环化和酰化等多步反应合成了一系列结构新颖的N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)酰胺类化合物.测试了所合成化合物的杀虫及抑菌活性,结果表明,新化合物大多化合物在200 mg·L^-1浓度下对东方粘虫(Mythimna separataWalker)具有一定的杀虫活性,尤其是N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)乙酰胺(8a)和N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)-3-氯-2,2-二甲基丙酰胺(8e)致死率可达70%;部分化合物在50 mg·L^-1浓度下对油菜菌核病菌的抑菌活性相对较好(54.5%~63.6%),优于triadimefon和chlorantraniliprole;部分化合物如N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)-3,3-二甲基丁酰胺80和N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)-4-氟苯甲酰胺(8h)对苹果轮纹病菌具有中等抑菌活性.值得注意的是,化合物8e的杀粘虫活性和对油菜菌核病菌的抑菌活性都较为突出,可用作新农药创制研究的新型参考结构.     

Synthesis and Antibacterial Studies of Some Novel 2-(Coumarin-3-yl)-5-mercapto-1,3,4-oxadiazoles Containing 2,4,6-Trisubstituted s-Triazine Derivatives

A new series of 2-(coumarin-3-yl)-5-mercapto-1,3,4-oxadiazoles based on various aryl thiourea/ureas incorporating a 1,3,5-s-triazine moiety is reported. The components of this series have been obtained by the reaction of cyanuric chloride (1) with 2-(coumarin-3-yl)-5-mercapto-1,3,4-oxadiazole (2). The prepared 2-{(coumarin-3-yl-1,3,4-oxadiazolyl)-5-thio}-4,6-dichloro-s-triazine (3) was subsequently treated with morpholine (4) to form 2-{(coumarin-3-yl-1,3,4-oxadiazolyl)-5-thio}-4-(morpholino)-6-chloro-s-triazine (5). This was further treated with various substituted aryl urea/thioureas (6a–k/7a–k) to afford the title compounds 8a–k and 9a–k, which were and tested for their antibacterial activity (MIC) against different microorganisms. The structures of the novel synthesized compound have been established on the basis of ¹H NMR and FT-IR data together with elemental analysis.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis of organo soluble aromatic poly(amide-imide)s based on 2-(5-(3,5-dinitrophenyl)-1,3,4-oxadiazole-2-yl)pyridine in an ionic liquid

In this work,the syntheses of new thermally stable poly(amide-imide)s with pendant 2-pyridyl-1,3,4-oxadiazole units in n-butyl methyl imidazolium bromide as reaction media have been reported.A new dicarboxylic acid has been derived from the reaction of diamine,2-(5-(3,5-diaminophenyl)-1,3,4-oxadiazole-2-yl)pyridine(POBD),and trimellitic acid anhydride.Polymers were prepared from the reaction of the diimide-diacid(DIDA) and different aromatic diamines in butyl methyl imidazolium bromide,[bmim][Br],in the ...