A Facile Access to Some New Pyrazole, 1,3,4-Thiadiazole,and Thiophene Derivatives via β-Ketosulfones

3-Bromoacetyl-1,5-diphenyl-1H-pyrazole-4-carbonitrile (1) reacts with sodium benzenesulfinate to give the corresponding ketosulfone 2. Treatment of 2 with hydrazonoyl chlorides 3a,b gives the 3,3′-bipyrazoles 5a,b. Ketosulfone 2 reacts also with arylidenemalononitriles to give the pyrazolylpyridones 10a,b. The reaction of compound 2 with phenylisothiocyanate and potassium hydroxide and treating intermediate with hydrazonoyl halides and with α-haloketones gives the 1,3,4-thiadiazoles 18a–c and thiophenes 21a–f, respectively.     

含1,3,4-噁二唑和1,3,4-噻二唑的硫醚类化合物的合成

在KOH作用下,芳甲酰肼1a～1e与CS2环化生成5-芳基-2-巯基-1,3,4-噁二唑(2a～2e);将2a～2e与氯乙酸乙酯反应,生成2-(5-芳基-1,3,4-噁二唑)硫基乙酸乙酯(3a～3e);3a～3e肼解得2-(5-苯基-1,3,4-噁二唑-2-硫基)乙酰肼(4a～4e);4a～4e与芳酰基异硫氰酸酯5a～5d反应得到双酰基氨基硫脲衍生物A1～A19;A1～A19在H2SO4催化下环合得到目标化合物B1～B19;目标化合物的结构经IR,1H NMR,MS,HRMS确证.     

Sterically hindered inversion of nitrogen atoms in cyclic hydrazines:N,N′-dialkyl-1,3,4-oxadiazolidines; 1,3,4-thiadiazolidine; and 4,5-benzo-1,2,3,6-tetrahydropyridazine

N,N′-Diisopropyl-substituted 1,3,4-oxadiazolidine3c, 1,3,4-thiadiazolidine6, 4,5-benzo-1,2,3,6-tetrahydropyridazine8, and new 3,4-dialkyl-1,3,4-oxadiazolidines9–14 were synthesized and studied. The configurational stability of the N atoms does not change on going from compound3c to itsS-analog6 and decreases in the case of pyridazine8. 3,4-Di-tert-alkyl-1,3,4-oxadiazolidines3d and11–14 were found to be promising objectes for optical resolution.     

Reactions of α-Aminoalkylphosphonates with Iso(thio)cyanatophosphates(phosphonates,phosphinates). Synthesis of 1,3,4-Diazaphospholidines and 1,3,4-Oxaza(thiaza)phospholines

Phenyl -aminoalkylphosphonates add to phenyl iso(thio)cyanates to give saturated heterocycles, 1,3,4-diazaphospholidin-2-(thi)ones. The reaction of diphenyl (-methylamino)benzylphosphonate with diethyl isothiocyanatophosphate involves initial formation of 1,3,4-tiazaphospholidine-2-thiones containing exo- and endocyclic phosphorus atoms. These products are readily hydrolyzed in air, yielding diethyl isothio- cyanatophosphate and phenyl hydrogen (-methylamino)benzylphosphonate. The final products of the reaction of chloromethyl isocyanatophosphonates with aminoalkylphosphonates are 1,3,4-oxazaphospholines. Phenyl aminoalkylphosphonates react with chloromethyl isocyanatophosphonates to give saturated heterocycles, 1,3,4-diazaphospholidines, whereas with chloromethyl isothiocyanatophosphonates 1,3,4-thiazaphospholines are formed.     

新型1,3,4-噻二唑衍生物的合成

以5-氨基-2-巯基-1,3,4-噻二唑为起始原料,对其2-位的巯基、5-位的氨基及杂环上3-位N原子进行结构修饰,合成了24个新型的1,3,4-噻二唑衍生物,其结构经1H NMR,13C NMR,IR和元素分析表征。     

1,3,4-噁二唑和1,3,4-噻二唑衍生物的设计、合成和生物活性研究

为了寻求新型抗肿瘤药物,设计并合成了一系列新型1,3,4-噁二唑和1,3,4-噻二唑衍生物,对这些化合物在人类四种癌细胞:B-16(皮肤黑色素瘤细胞)、PC-3(人前列腺癌细胞)、U87(人原发性胶质母细胞瘤细胞)和A549(人非小细胞肺癌细胞)进行抗肿瘤活性评价.结果显示部分化合物具有较好的抗肿瘤活性,尤其是5-{6-[4-(2-羟基乙基)哌嗪-1-基]-2-甲基嘧啶-4-基氨基}-[1,3,4-噻二唑-2-羧酸(2-甲氧基苯基)酰胺(8b)]和5-{6-[4-(2-羟基乙基)哌嗪-1-基]-2-甲基嘧啶-4-基氨基}-[1,3,4-噻二唑-2-羧酸(4-甲氧基苯基)酰胺(8c)],对四种癌细胞都显示出较高的抗肿瘤活性,其抑制活性均优于阳性对照达沙替尼,随后对这类化合物抑制肿瘤的可能靶点开展了进一步研究.     

Synthesis,characterization, and optoelectronic properties of heteroleptic iridium complexes containing substituted 1,3,4-oxadiazole and β-diketone as ligands

The new heteroleptic iridium(III) complexes (BuOXD)₂Ir(tta) and (BuOXD)₂Ir(tmd) [BuOXD?=?2-(4-butyloxyphenyl)-5-phenyl[1,3,4]oxadiazolato-N4,C2, tta?=?1,1,1-trifluoro-4-thienylbutane-2,4-dionato, tmd?=?2,2,6,6-tetramethylheptane-3,5-dionato] have been synthesized and characterized. These complexes have two cyclometalated ligands (C^N) and a bidentate diketone ligand (X) [C^N)₂Ir(X)], where X is a β-diketone with trifluoromethyl, theonyl or t-butyl groups. The color tuning with the change in electronegativity of substituents in the β-diketones has been studied. Photoluminescence spectra of the complexes showed peak emissions at 523 and 549?nm, respectively. The electroluminescent properties of these complexes have been studied by fabricating multi layer devices with device structure ITO/α-NPD/8% iridium complex doped CBP/BCP/Alq₃/LiF/Al. The electroluminescence spectra also showed peak emissions at 526 and 570?nm for (BuOXD)₂Ir(tta) and (BuOXD)₂Ir(tmd), respectively. These metal complexes showed good thermal stability in air to 340°C.     

Synthèse de 2-pyrazolinyl,isoxazolinyl,1,2,3-triazolyl et 1,3,4-oxadiazolyl méthylmercapto-1-pyrazolyl benzimidazole

Synthesis of 2-pyrazolinyl, isoxazolinyl,1,2,3-triazolyl and 1,3,4-oxadiazolyl methylmercapto-1-pyrazolyl benzimidazole. The reaction of N-aryl C-ethoxycarbonylnitrilimine, phenylnitriloxide and benzylazide with 9 and 10 afforded 2-pyrazolinyl, isoxazolinyl and 1,2,3-triazolyl methylmercapto-1-pyrazolylbenzimidazole 12–15. Cyclocondensation of 2-pyrazoly-l-benzimidazolylthio acetic acid hydrazide 16 with carbon disulfide gave 2-(2-thioxo-1,3,4-oxadiazolyl) methylmercapto-1-pyrazolyl benzimidazole 17. The structures of the products obtained have been established by ¹H-, ¹³C-NMR, IR and mass spectrum data. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS. Tous droits réservés1-pyrazolylbenzimidazole / cycloaddition / regioselectivity / cyclocondensation     

Copper-catalyzed direct cross coupling of 1,3,4-oxadiazoles with trans-β-halostyrenes: synthesis of 2-E-vinyl 1,3,4-oxadiazoles

The first direct C–H alkenylation of 1,3,4-oxadiazoles with trans-β-halo olefinic system has been carried out using a combination of CuI/DMEDA as a catalyst. A wide range of 2-E-vinyl-substituted oxadiazoles were obtained in high yields (85–93%).     

含氟1,3,4-噁唑啉和1,3,4-噁二唑类化合物的合成及其抗癌活性

对氟苯甲酰腙与乙酸酐或丙酸酐反应后再脱水环化制得2-苯基-3-乙酰基-5-对氟苯基-1,3,4-噁唑啉(3)或2-苯基-3-丙酰基-5-对氟苯基-1,3,4-噁唑啉(4).N-对氟苯甲酰基-N′-苯甲酰肼在POCl3存在下脱水环化制得2-苯基-5-对氟苯基-1,3,4-噁二唑(6).新化合物3,4和6的结构经1H NMR,IR,MS和元素分析表征.用MTT方法评价了其对HepG-2,A549-1和231-2癌细胞株的体外生长抑制活性.结果表明,3,4和6均具有潜在的体外抑制癌细胞生长活性,其中3的活性最强.     

1,3,4-均三唑并[2,1-b]-1,3,4-噻二唑衍生物的合成及生物活性

以5-对甲苯基-1-氨基-2-巯基-1,3,4-均三唑和取代苯氧乙酰异硫氰酸酯为原料, 合成了10个未见文献报道的5-对甲苯基-2-取代苯氧乙酰氨基均三唑并[2,1-b]-1,3,4-噻二唑类化合物, 通过元素分析, 1H NMR, IR和MS确定化合物的结构, 初步生物活性测试表明目标化合物具有较好的除草活性.     

New 1,2,4‐ and 1,3,4‐oxadiazole materials: synthesis,and mesomorphic and luminescence properties

The synthesis and liquid crystalline properties of new series of 1,2,4‐ and 1,3,4‐oxadiazole derivatives (2a–f and 5a–f respectively) are reported. These compounds contain only one terminal flexible alkoxy chain, the other terminal substituent is a protecting benzyl group. All compounds of series 2 exhibit an enantiotropic nematic phase. The homologue with the longest chain (2f) displays an enantiotropic dimorphism smectic A– nematic. None of the compounds of series 5 shows mesomorphism and only crystal–isotropic transitions were observed. The liquid crystalline properties were investigated by differential scanning calorimetry, polarizing optical microscopy and X‐ray measurements. Luminescence properties, in chloroform solution, of 2f and the series 5 compounds were evaluated. Good photoluminescence quantum yields for compounds of series 5 were observed. Compound 2f, incorporating the 1,2,4‐oxadiazole ring shows a very strong reduction in emissive properties.     

[4 + 1] Cyclization of benzohydrazide and ClCF2COONa towards 1,3,4-oxadiazoles and 1,3,4-oxadiazoles-d5

A facile synthesis of 1,3,4-oxadiazoles and 1,3,4-oxadiazoles-d₅ via [4 + 1] cyclization of ClCF₂COONa with non-amine compounds containing amino groups is developed. Of note, this is the first time that halofluorinated compounds are used as C1 synthon to construct deuterated nitrogen-heterocyclic compounds. The current protocol features simple operation, readily accessible raw materials, wide substrate scope and valuable products     

1,3,4-噻二唑衍生物合成及其生物活性研究进展

1,3,4-噻二唑是含有N、S杂原子的五元杂环化合物,具有多种生物活性。目前,1,3,4-噻二唑及其衍生物广泛用于生物、医药等领域,尤其在抗菌、抗肿瘤、抗癌等方面的研究已取得重大突破。由于1,3,4-噻二唑结构的特殊性以及优越的生物活性,对其进行研究有重要意义。本文主要概述了近年来1,3,4-噻二唑衍生物的几种合成方法以及其在抗菌、抗肿瘤、抗癌方面的研究进展。     

3-硝基-1,3,4-三唑-5-酮金属(Li,Na, Pb,Cu)盐的制备反应热动力学

在常压、298.15 K条件下, 用RD496-2000微量热仪开展了3-硝基-1,3,4-三唑-5-酮(NTO)金属(Li, Na,Pb, Cu)盐制备反应的热动力学研究, 得到了反应过程中的热力学参数(活化焓、活化熵和活化自由能), 速率常数和动力学参数(活化能、指前因子和反应级数), 还得到了在25-40℃范围内NTO金属(Li, Na, Pb, Cu)盐制备反应过程的反应焓. 结果表明, NTO金属(Li, Na, Pb, Cu)盐的制备反应较容易发生. 基于Hess定律, 得到了Δ_fH_m⁰ (Li(NTO)·2H₂O, aq, 298.15 K)和Δ_fH_m⁰ (Na(NTO)·H₂O, aq, 298.15 K)的值.     

1,2, 4λ3-thiaazaphosphole, 1,2λ3, 4λ3-thiadiphosphole und 1,2λ3-thiaphosphole aus 1,3,4-oxathiazol-2-onen und phosphaalkenen

The title compounds are described for the first time and are the result of (3+2)- and (4+2)-cycloaddition reactions with phosphaalkenes.     

Cyclocondensation of 2-Amino-1,3,4-thiadiazoles with β-Sulfonylvinyltrifluoromethyldiols

A series of CF₃-containing 6,7-dihydro-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-7-ols was obtained by the interaction of 2-amino-1,3,4-thiadiazoles with -sulfonylvinyltrifluoromethyldiols and their stereochemistry was established. The structure of 5-(phenylsulfonyl)-7-(trifluoromethyl)-6,7-dihydro-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-7-ol was confirmed by X-ray crystallography.     

N-H?S hydrogen bonding in 2-mercapto-5-methyl-1,3,4-thiadiazole. Synthesis and crystal structures of mercapto functionalised 1,3,4-thiadiazoles

The synthesis and crystal structures of three mercapto functionalised 1,3,4-thiadiazoles and the crystal structure of 2-mercapto-5-methyl-1,3,4-thiadiazole are described. In the solid state, 2-mercapto-5-methyl-1,3,4-thiadiazole 1 forms a thioamide tautomer as shown by FTIR and Raman spectroscopy as well as X-ray crystallography and as theoretically predicted. The molecules are connected to form chains via N-H?S hydrogen bonds with N?S=328.3 pm. Bis(2-methyl-1,3,4-thiadiazolyl)-5,5′-disulfide 2, the disulfide of 1, as well as 2-(tert-butyldithio)-5-methyl-1,3,4-thiadiazole 3 and 2,5-bis(tert-butyldithio)-1,3,4-thiadiazole 4 have been synthesised and characterised by vibrational spectroscopy and X-ray diffraction.     

Synthesis,insecticidal activities,and structure–activity relationships of 1,3,4-oxadiazole-ring-containing pyridylpyrazole-4-carboxamides as novel insecticides of the anthranilic diamide family

The preparation of novel anthranilic diamide derivatives is extremely important for agricultural pest control. In this study, pyridylpyrazole-4-carboxamides containing a 1,3,4-oxadiazole ring were designed and synthesized via the dehydration of aromatic hydrazine derivatives and formanilides in the presence of an alkali. The insecticidal activities of these new compounds against the diamondback moth (Plutella xylostella) were evaluated. N-(4-chloro-2-methyl-6-(5-(4-nitrophenyl)-1,3,4-oxadiazol-2-yl)phenyl)-5-methyl-1-(pyridin-2-yl)-1H-pyrazole-4-carboxamide ( 8h6 ) showed 67%, 50%, 34%, 20%, and 17% activity at concentrations of 100, 50, 10, 5, and 1 μg ml⁻¹, respectively. Density functional theory calculations showed that the introduction of the 1,3,4-oxadiazole ring significantly changed the electron distributions in both the highest occupied and lowest unoccupied molecular orbitals, resulting in these compounds having much larger energy gaps than the well-known insecticide chlorantraniliprole, which may account for their lower activity. The results of this study demonstrate that anthranilic diamides substituted with a 1,3,4-oxadiazole ring are effective insecticides that can be used for pest management.     

One-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles under ultrasonic irradiation

A facile one-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles was achieved by ultrasonic irradiation of a mixture of 1- naphthylacetyl chloride,NH_4CNS,CH_2Cl_2 and PEG-400 for 1.5 h at 10-20℃and subsequent irradiation for 1.5h in the presence of N-arylglycine hydrazides.This method requires short time and gives thiadiazoles in high yields.