Synthesis of 3-[(aryl)-1,2,4-oxadiazol-5-yl]propionic acids

Seven 3,5-disubstituted oxadiazole derivatives, 3a-g , have been prepared by direct condensation of appropriate benzamidoxime with succinic anhydride. Spectroscopic properties, especially uv, ir and mass spectra confirmed the cyclic 1,2,4-oxadiazole structure. No ring-opened intermediate or side product could be observed. The ¹H-nmr assignments of the two CH₂ groups were unequivocally made by acid- and base-induced shifts.     

Synthesis and Antimicrobial Activity of 3-{2-[(1-Aryl-1H-1,2,3-triazol-4-yl)methoxy]-5-fluorophenyl}isoxazoles

Russian Journal of General Chemistry - A novel series 3-{2-[(1-aryl-1H-1,2,3-triazol-4-yl)methoxy]-5-fluorophenyl}isoxazoles derivatives is synthesized from 1-(5-fluoro-2-hydroxyphenyl)ethanone....     

Synthesis and structure of 4-[(4-Nitro-1,2,5-oxadiazol-3-yl)-NNO-azoxyl]-1, 2,5-oxadiazol-3-amine

The synthesis of the energetic compound 4-[(4-nitro-1,2,5-oxadiazol-3-yl)-NNO-azoxyl]-1,2,5-oxadiazol-3-amine (3) was achieved in two steps from diaminofurazan (1). Compound 3 was characterized by X-ray diffraction. From the X-ray structure a bifurcated intramolecular H bond between O(2)-H(2)-N(4) was observed. In addition, intramolecular H bonding was observed between H(1) and N(7) of an adjacent molecule. One molecule of ethanol and one-half molecule of water per molecule of3 was observed in the crystal lattice. However, no H bonding was observed between the solvent molecules and3 in the crystal lattice. Despite the presence of solvent in the crystal lattice,3 was found to have a high crystal density (d=1.856 g/cm³).     

Design,Synthesis, and Biological Evaluation of Novel 2-(4-Arylsubstituted-1H,2,3-triazol-1-yl)-N-{4-[2-(thiazol-2-yl)benzo[d]thiazol-6-yl]phenyl}acetamide Derivatives as Potent Anticancer Agents

Russian Journal of General Chemistry - A novel series of benzothiazole bearing 1,2,3-triazole derivatives 11a–11j are synthesized, and their structures are confirmed by 1H and 13C NMR, and...     

Synthesis and characterization of 2-alkyl -5-{4-[(3-nitrophenyl-5-isoxazolyl)methoxy]phenyl}-2H-tetrazoles

Heteroaryl substituted analogs of antirhnoviral (A), was prepared by a convergent approach. 3-Nitrophenyl-5- bromooromethylisoxazoles 5a–b were synthesized by [3+2] cycloaddition of 3-(benzoyloxy)-propyne 2 to in situ generated arylnitrile oxides followed by deprotection of cycloadducts 3a–b and bromination of the resulting alcohols 4a–b. Coupling of 3- nitrophenyl-5-bromooromethylisoxazoles (5a–b) with 4-[5-(2-alkyl-2H-tetrazolyl)]phenols (6a–d) in N-methylpyrrolidinone under mild conditions afforded a new series of 2-alkyl-5-{4-[1-(3-nitrophenyl-5-isoxazolyl)methyloxy]phenylr}-2H-tetrazoles (7a–h) in high yields. The structures of the synthesized compounds were confirmed by their ¹H NMR, Mass spectral, and Elemental Analysis data.     

Design,Synthesis, and Anticancer Evaluation of N-(4-{5-[4-(5-Methyl-1,3,4-oxadiazol-2-yl)phenyl]-4-(2,3,4-trimethoxyphenyl)-1,3-thiazol-2-yl}phenyl)benzamides

Russian Journal of Organic Chemistry - A series of substituted N-(4-{5-[4-(5-methyl-1,3,4-oxadiazol-2-yl)phenyl]-4-(2,3,4-trimethoxy­phenyl)-1,3-thiazol-2-yl}phenyl)benzamides were designed...     

An Efficient Synthesis and Antimicrobial Activity of 5-{2-[(1-Aryl-1H-1,2,3-triazol-4-yl)methoxy]-5-bromophenyl}isoxazoles

A novel series of 1,2,3-triazolyl isoxazole derivatives is synthesized from the corresponding propargylated isoxazoles and a number of aryl azides by the Click reaction. The highest yields of the reaction are achieved in the presence of copper sulphate pentahydrate and sodium ascorbate, and using DMF:water (2:1) as a medium. The compounds structures are elucidated from various spectral data. Antimicrobial activity tests of the title compounds demonstrate their moderate to good results compared to the standard.

     

（E）-3-{4-[（3，5，6-三甲基吡嗪-2-基）甲氧基]-芳基}丙烯酸的合成

以川芎嚷为起始原料,经溴化,O-烷基化和Knoevenagel缩合反应合成了2个(E)-3-{4-[(3,5,6-三甲基吡嗪-2-基)甲氧基]-芳基}丙烯酸类化合物,其结构经1H NMR,13C NMR,IR和MS表征.     

N-{3-氯4-[(3-氟苄基)氧基]苯基}-6-碘喹唑啉-4-胺的合成工艺改进

以2-胺基-5-碘苯甲酸为起始原料,经四步反应合成了新型喹唑啉类抗肿瘤药物拉帕替尼的关键中间体-N-{3-氯4-[(3-氟苄基)氧基]苯基}-6-碘喹唑啉-4-胺,总收率77.9%,其结构经1H NMR和ESI-MS确证.Williamson醚化反应的最佳条件为:4-(6-碘喹唑啉-4-基氨基)-2-氯苯酚(5)30.0 mmol,K2CO3 24.8 g,18-冠-6 0.79 g,KI 0.49 g,丙酮250 mL.于35℃反应12 h,收率90.1%.     

Synthesis and Herbicidal Activity of O,O-Dialkyl(phenyl)-N-{1-[(6-chloropyridin-3-yl)methyl]-4-cyano-1H-1,2,3-triazol-5-yl}-1-amino-1-substitutedbenzyl-phosphonates

Abstract

A series of novel α-amino phosphonate derivatives containing both pyridine and 1,2,3-triazole moieties 4 were synthesized via a multi-step reaction. First, the condensation of 5-amino-1-[(6-chloropyridin-3-yl) methyl]-4-cyano-1H-1,2,3-triazole with various aromatic aldehydes in the presence of magnesium perchlorate afforded imines 3 in moderate yields; second, imines 3 reacted with dialkyl phosphites or triphenyl phosphite to give the title compounds 4 in moderate to good yields. Their structures were elucidated by spectroscopic data (IR, ¹H NMR, ³¹P NMR, ESI-MS) and elemental analysis. The preliminary bioassay (in vitro) indicated that some of the title compounds 4 possessed moderate herbicidal activities against dicotyledonous plants (Brassica campestris L) at a concentration of 100 mg/L. However, compounds 4 did not exhibit herbicidal activities against Brassica campestris L at a concentration of 10 mg/L.

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.

GRAPHICAL ABSTRACT      

Carbon-13 NMR Studies of 3-Aryl-4-(5-aryl-Δ 2-1,2,4-oxadiazolin-3-yl)sydnones and 3-Aryl-4-(5-aryl-1,2,4-oxadiazol-3-yl)sydnones

The ¹³C NMR spectra of twelve 3-aryl-4-(5-aryl-Δ²-l,2,4-oxadiazolin-3-yl)sydnones and twelve 3-aryl-4-(5-aryl-l,2,4-oxadiazol-3-yl)sydnones have been measured and assigned by means of proton-noise decoupling and DEPT-experiments. The coupling constants were determined by means of gated decoupling, and NOE effects were observed by comparison of proton-decoupled and inverse-gated decoupled spectra. Differences shown by the oxadiazoline and the oxadiazole rings and the substitution effects are discussed.     

新型1-(4-取代苯基)-3-[4-(4-氧香豆素基)苯基]硫脲衍生物的合成及其抑菌活性

以4-羟基香豆素为原料,经氯化、醚化和异硫氰酸化3步反应制得中间体——4-(4-异硫氰酸酯苯氧基)香豆素(3);3与取代芳香胺经加成反应合成了9个新型的1-(4-取代苯基)-3-[4-(4-氧香豆素基)苯基]硫脲衍生物(4a~4i),其结构经1H NMR,13C NMR,IR和MS(ESI)表征。采用浑浊度法测试了4的抑菌活性。结果表明:4a、4b、4e和4f抑制烟草青枯菌活性EC50值分别为112.02、121.39、88.72和86.90μg·mL~(-1),优于噻菌铜(130.25μg·mL~(-1));4a、4b、4e和4f抑制番茄青枯菌活性EC50值分别为107.89、110.69、82.43和82.48μg·mL~(-1),优于噻菌铜(123.94μg·mL~(-1))。     

Microwave Assisted Synthesis and Antimicrobial Activity of (E)-1-{2/3/4-[(1-Aryl-1H-1,2,3-triazol-4-yl)methoxy]phenyl}-3-(2-morpholinoquinolin-3-yl)prop-2-en-1-ones

Russian Journal of General Chemistry - A novel series of (E)-1-{2/3/4-[(1-aryl-1H-1,2,3-triazol-4-yl)methoxy]phenyl}-3-(2-morpholinoquinolin-3-yl)prop-2-en-1-ones is synthesised from terminal...     

Synthesis of 3-(5-Aryl-1,3,4-oxadiazol-2-yl)chromones

A general method was proposed for the synthesis of 3-(5-aryl-1,3,4-oxadiazol-2-yl)chromones starting from 3-formylchromone. This aldehyde yields acylhydrazones, from which the corresponding unstable nitrile imines are generated. These intermediates undergo intramolecular 1,3-dipolar cycloaddition.     

Synthesis of 3-(5-Aryl-1,3,4-oxadiazol-2-yl)chromones

A general procedure was proposed for the synthesis of 3-(5-aryl-1,3,4-oxadiazol-2-yl)chromones by reaction of 3-formylchromone with aroylhydrazines, transformation of the corresponding acylhydrazones into 1,3-dipoles by the action of bromine in the presence of sodium acetate, and intramolecular ring closure.     

Alternative Synthesis of 5-(1H-Pyrazol-4-yl)-2-{6-[(2,2,6,6-tetramethylpiperidin-4-yl)oxy]pyridazin-3-yl}phenol

A scalable and environmentally benign route to the free base of branaplam, a small molecule splicing modulator, was identified and developed. This alternative approach circumvented the inherent risk of dioxin formation associated with ortho-halo phenol derivatives present in the previous route. A Friedel–Crafts approach provided a reliable access to the key intermediate, subsequently followed by a Suzuki–Miyaura cross-coupling. Multiple process aspects of the synthetic approach were evaluated, and a robust process for its large-scale synthesis was developed and successfully demonstrated.     

Synthesis and Antibacterial Activity of Some {6-[(1H-1,2,3-Triazol-4-yl)methoxy]-3-methylbenzofuran-2-yl}(4-bromophenyl)methanone Derivatives

Russian Journal of General Chemistry - A series of novel benzofuran?1,2,3-triazole hybrid heterocyclic molecules were synthesized using a click chemistry approach. The structure of the...     

Regioselective O-alkylation: synthesis of 1-{2-[(2-chloroquinolin-3-yl)methoxy]-6-chloro-4-phenylquinolin-3-yl}ethanones

An efficient and regioselective O-alkylation of amides with a variety of electrophiles in the presence of silver nanoparticles is reported as part of our recent research on building blocks for synthesis of natural products. The nano-silver catalyst initiates O-alkylation of the amides by heteroalkyl halides. Reaction of equimolar 3-acetyl-6-chloro-4-phenylquinolin-2(1H)-one and 2-chloro-3-(chloromethyl)quinolines in the presence of silver nanoparticles in DMSO solution under reflux condition leads to the formation of 1-{1-[2-chloroquinolin-3-yl)methoxy]-6-chloro-4-phenylquinolin-3-yl}ethanones.     

Synthesis and Anticancer Evaluation of 2-{4-[5-(5-Substituted arylpyrimidin-2-yl)-1H-pyrazol-3-yl]-phenyl}thiazolo[4,5-b]pyridine Derivatives

Russian Journal of General Chemistry - In the present study a new series of 2-{4-[5-(5-substituted arylpyrimidin-2-yl)-1H-pyrazol-3-yl] phenyl}thiazolo[4,5-b]pyridine derivatives (11a–11j)...