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4‐(2‐Chlorobenzyl)‐1‐(furan‐2‐yl)‐[1,2,4]triazolo[4,3‐a]quinazolin‐5(4H)‐one is a triazoloquinazolinone compound with broad‐spectrum biological activity. In this study, the four‐step method was used to synthesize the title compound, and its structure was confirmed by Fourier‐transform infrared spectroscopy (FT‐IR), proton nuclear magnetic resonance (1H NMR), 13‐carbon nuclear magnetic resonance (13C NMR) spectroscopy, and mass spectroscopy (MS). Further, its single crystal was characterized by X‐ray diffraction. The density functional theory was used to calculate the optimal structure of the molecule. The results demonstrated that the analyzed structure was consistent with the crystal structure determined by single‐crystal diffraction. In addition, discrete Fourier transform was used to study the molecular electrostatic potential and Frontier molecular orbital of the title compound, revealing a few of the compound's physicochemical properties. [ABSTRACT FROM AUTHOR]

New representatives of [1,2,4]triazolo[1,5‐a]pyridine‐8‐carbonitriles were synthesized via the condensation of β‐diketones or β‐dialdehydes and characterized using MS spectrometry, 1H, 13C and, 19F NMR and IR spectroscopy. Crystal structures of two compounds were established using X‐ray analysis and showed that title compounds are prone to the formation of planar molecules. The absence of band responsible for CN stretching vibration in trifluoromethyl‐containing compounds was explained using the DFT calculations method, which also showed a significant influence of fluorines introducing on the energy gap between HOMO and LUMO. [ABSTRACT FROM AUTHOR]

A series of tris(5‐aryl‐1H‐tetrazol‐1‐yl)methanes (3a‐3g) and 2‐dichloromethyl‐5‐aryl‐2H‐tetrazoles (4a‐4d) were synthesized by reaction of 5‐aryl‐NH‐tetrazoles with trichloromethane in strong aqueous basic condition. The compounds obtained were fully characterized by means of HRESI‐MS, 1H and 13C{1H} NMR spectroscopies, as well as by single‐crystal X‐ray diffraction (for 3a, 3b, 4d). Inspection of the X‐ray diffraction data and Hirshfeld surface analysis for tris(5‐aryl‐1H‐tetrazol‐1‐yl)methanes 3a,b and 2‐dichloromethyl‐5‐aryl‐2H‐tetrazole 4d showed the presence of noncovalent π‐hole•••lone pair and π‐hole•••π interactions involving electrophilic tetrazole carbon atom. [ABSTRACT FROM AUTHOR]

The preferred sites for the benzylation of adenine under basic conditions were proven to be the N9 and N3 positions. Formation of the N9-benzyladenine product is favored in polar aprotic solvents, such as DMSO, whereas the proportion of N3-benzyladenine formed increases as the proportion of polar protic solvents, such as water, increases. X-ray crystal structures were obtained for both N9-benzyladenine and N3-benzyladenine. 1H-13C HMBC NMR spectroscopy revealed diagnostic correlations used to assign the 1H and 13C NMR chemical shifts confirming that the solution structures in three different solvents were the same as the isolated crystals. 13C NMR assignment for N9-benzyladenine, N3-benzyladenine, and N7-benzyladenine was confirmed by computation using ADF. [ABSTRACT FROM AUTHOR]

A novel series of ethyl 1,3-disubstituted-1,6-dihydropyrrolo[2,3-c]pyrazole-5-carboxylates can be rapidly and efficiently synthesized in excellent yields by condensing a variety of 1,3-substituted-4-formyl-5-chloropyrazole with ethyl isocyanoacetate in the presence of 1-methyl-3-butylimidazolium hydroxide under microwave irradiation. The simple experimental procedure, DMSO-free condition, short period of conversion, and excellent yields are the advantages of the present method. The structures of the novel compounds are confirmed by IR, 1H NMR, 13C NMR, MALDI-TOF MS, and elemental analysis. [ABSTRACT FROM AUTHOR]

High resolution MS, 1D, and 2D NMR were used to determine the structure of a unique cationic impurity generated during the synthesis of Preladenant™ H/D exchange experiments were performed by both MS and NMR to confirm the acidic nature of the cationic dihydroimidazole proton. The presence of three exchangeable protons was established by MS experiments and the disappearance of the C11 proton in 1H-NMR spectrum on equilibration with D2O confirmed the acidic nature of the cationic dihydroimidazole proton. A piperazine ring contraction mechanism is proposed for the formation of the cationic dihydroimidazole. [ABSTRACT FROM AUTHOR]

Synthesis of some novel 1,2,4-triazoles, 1,3,4-oxadiazoles and 1,3,4-thiadiazoles bearing a ( R) 5-(1-(4-(5-chloro-3-fluoropyridin-2-yloxy)phenoxy)ethyl) unit, as a moiety of commercial herbicide, using their thiosemicarbazides in an alkaline, iodine and acidic media is reported, respectively. The structure of the synthesized compounds was characterized by IR, 1H, 13C NMR spectroscopic data, and elemental analyses. The herbicidal activities of synthesized compounds were evaluated against Echinochloa cruss-galli, Avena fatua, and Sorgum halepense weeds. Compounds 7 and 12a showed potential herbicidal activity against gramineous weeds. Our results may provide some guidance for synthesis development of some novel oxa or thiadiazole and triazole-based herbicidal lead structures. [ABSTRACT FROM AUTHOR]

Two novel compounds, 8-[2-(2-thienyl)vinyl]-10,10-dimethyl-10 H-pyrido[1,2- a] indolium perchlorate ( 3a) and 8-[2-(5-phenyl-2-thienyl)vinyl]-10,10-dimethyl-10 H-pyrido[1,2- a]indolium perchlorate ( 3b) were synthesized and characterized by IR, 1H-NMR, elemental analyses, and X-ray diffraction. Crystal structural analysis suggested that either 3a or 3b exhibited good coplanarity and rings and vinyl in the target molecule could make up a large conjugated system. Ultraviolet-visible absorption analysis indicated both 3a and 3b possessed large maximum absorptions, and 3b underwent a significant redshift (43.0 nm) in comparison with 3a. [ABSTRACT FROM AUTHOR]

A series of novel 1,5-diaryl-1 H-pyrazol-3-oxy derivatives containing oxyacetic acid or oxy(2-thioxothiazolidin-3-yl)ethanone moieties were prepared from methyl 3-arylacrylates via a serial of reactions included addition-cyclization, oxidation, substitution, hydrolysis, and condensation. Their structures were confirmed by 1H-NMR, 13C-NMR, IR, and elemental analysis. In addition, the crystal structure of the compound 2-(1,5-diphenyl-1 H-pyrazol-3-yloxy)-1-(2-thioxothiazolidin-3-yl)ethanone was determined by single crystal X-ray diffraction analysis. Bioassay results indicated that the compound 2-(5-(4-chlorophenyl)-1-phenyl-1 H-pyrazol-3-yloxy)-1-(2-thioxo-thiazolidin-3-yl)ethanone exhibited moderate inhibitory activity against Gibberella zeae at the dosage of 10 μg mL−1. [ABSTRACT FROM AUTHOR]

A series of quinazoline derivatives were synthesized via the cyclization of N, N′-disubstituted thiourea derivatives in the mixed solvent of acetontrile and aqueous NaOH by ultraviolet light irradiation. All the compounds are characterized by IR, 1HNMR, 13CNMR, MS, and element analysis. The absolute configurations of 3a was determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Triaryltriazoles are of interest in iron(II) complexes designed to study spin-crossover properties. In this study, three new asymmetrical substituted triaryltriazoles, 3-( p-R-phenyl)-4-( p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazoles (R = OCH3, 5a; Cl, 5b; Br, 5c), were successfully synthesized from 2-picolinic acid by a three-step reaction through an intermediate N-( p-R-phenylcarbonyl)- N′-(2-pyridylcarbonyl)hydrazine ( 4a-4c). Yield of 5a- 5c is in the range from 74 to 87%. The compounds 5a- 5c were characterized by UV, FTIR, 1H-NMR, electrospray ionization mass spectrum spectra, and elemental analysis. Additionally, the absolute configurations of 5a-5c were determined by single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

A highly colored impurity formed at low levels during the preparation of 3-amino N,N-dimethyl salicylamide was isolated and identified as 2-amino- N,N,N′,N′-tetramethyl-3-oxo-3 H-phenoxazin-4,6-dicarboxamide using mass spectrometry and two-dimensional NMR methods that included long-range 1H-15N heteronuclear chemical shift correlation data to assemble the proton-deficient 'right-half' of the 2-aminophenoxazin-3-one nucleus. The structure was independently confirmed using computer-assisted structure elucidation methods and by synthesis. [ABSTRACT FROM AUTHOR]

2-Aryl-4-methyl-5-acetylthiazoles, which were prepared from arylthioamides and chloroacetylacetone, were treated with 6-substituted-3-formylchromones or arylaldehydes to give a series of eighteen new thiazolylchalcones in good yields. The structures of all the synthesized compounds were characterized by 1H NMR, 13C NMR, and ES-MS spectrometry. Additionally, the crystal structures of two of these chalcones were determined by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

A new convenient synthon for heterocyclic chemistry, namely 1 H-pyrazolo[3,4- b]pyridin-3-ylguanidine was successfully prepared by selective guanylation of 1 H-pyrazolo[3,4- b]pyridin-3-amine. A series of 3,4-dihydropyrido[2′,3′:3,4]pyrazolo[1,5- a][1,3,5]triazin-2-amines was synthesized from 1 H-pyrazolo[3,4- b]pyridin-3-ylguanidine using aldehydes or ketones as one-carbon inserting reagents. The tautomeric preferences of the products were determined using spectroscopic ( e.g., 2D NOESY NMR) and single crystal X-ray diffraction data. [ABSTRACT FROM AUTHOR]

A green and convenient approach to the synthesis of a series of 4,7-diaryl-5-oxo-4 H-benzo[ b]pyran derivatives from appropriate aromatic aldehydes and 5-aryl-1,3-cyclohexanedione with malononitrile in the presence of dilute HCl as catalyst (30 mmol/L) is described. This method provides several advantages such as environmental friendliness, low cost, high yields, and simple work up procedure. The structures of all compounds were characterized by infrared (IR), mass spectrometry (MS), 1H NMR, and elemental analysis. The crystal structure of trans/ cis-2-amino-3-cyano-7-(4′-methoxo-phenyl)-4-phenyl-5-oxo-4 H-benzo[ b]pyran, g, was determined by single crystal X-ray diffraction analysis. The crystal of compound g belongs to monoclinic with space group P 21/c, a = 8.477(3) nm, b = 18.948(6) nm, c = 24.915(7) nm, α = 90.00°, β = 107.388(11)°, γ= 90.00°, Z = 8, V = 3.819(2) nm3, R1 = 0.0754, wR2 = 0.2042. [ABSTRACT FROM AUTHOR]

A series of 2,6-diphenyl-4 H-pyrazolo[5,1- c][1,4]oxazin-4-ones has been synthesized via a lactonization of 1-(2-oxo-2-phenylethyl)-3-phenyl-1 H-pyrazole-5-carboxylic acids in the presence of Ac2O at reflux temperature. The products were isolated by simple filtration in excellent yields and were characterized by IR, 1H-NMR, and HRMS. The molecular structure was confirmed by the X-ray crystal analysis of one compound that was prone to crystallization. [ABSTRACT FROM AUTHOR]