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41.
Mohammad Ali Zolfigol Davood Azarifar Iraj Mohammadpoor-Baltork Behrooz Maleki 《Tetrahedron letters》2006,47(5):833-836
4-(p-Chloro)phenyl-1,3,4-triazole-3,5-dione is used as an effective oxidizing agent for the oxidation of 1,3,5-trisubstituted pyrazolines to their corresponding pyrazoles under mild conditions with moderate to good yields at room temperature. 相似文献
42.
K. Yu. Chegaev A. N. Kravchenko O. V. Lebedev Yu. A. Strelenko P. A. Belyakov 《Chemistry of Heterocyclic Compounds》2002,38(10):1250-1252
N-Trimethylsilyl derivatives of 2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones have been prepared for the first time and the electrophilic substitution reaction of the trimethylsilyl group has been studied. 相似文献
43.
Arrhenius parameters values, in non-isothermal kinetic vaporisation processes for a series of compounds with related structures,
have been calculated. This was made using a method of calculation that allows to find the most probable vaporisation mechanisms.
According to this method DTG curves were compared with some theoretical ones reported in literature, whose shape results to
be only a function of the mechanisms. In this way the choice of the mathematical functions which can be inserted in the kinetic
equations, was influenced by the shape of the DTG plots and other thermal analysis signals thus allowing to choose the most
probable mechanisms.
The kinetic parameters derived from these mechanisms were compared, using statistical analysis, with those obtained from another
method of calculation based on ‘a priori’ vaporisation mechanism chosen for the investigated liquid–gas transition.
The standard deviations of the slope and of the intercept, together with the standard deviation and the square correlation
coefficient (r
2) of the linear regression equations related to the mechanisms of the two methods were calculated. Student t-test, Fisher F-test, confidence intervals (c.i.) and residuals valueswere also given.
Statistical analysis shows that the mechanisms obtained with the former method (diffusive and geometrical models) and the
related Arrhenius parameters result to be more significant (in terms of probability) than the corresponding quantities of
the latter for which a first-order model was chosen.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
44.
Pierre Raboisson Dominique SchultzClaire Lugnier Romain MathieuJean-Jacques Bourguignon 《Tetrahedron letters》2003,44(4):703-705
An expedient synthesis of 8-acylamidopyrazolo[1,5-a]-1,3,5-triazines was developed by treating 8-amino-4-[N-(4-aminophenyl)-N-(methyl)amino]pyrazolo[1,5-a]-1,3,5-triazine with various acyl chlorides following by the displacement of the so-formed N-(methyl)-N-[4-(acylamido)phenyl]amino leaving group with various amines. Applications to high-throughput synthesis are suggested. 相似文献
45.
Two water‐soluble 6‐(pyrazin‐2‐yl)‐1,3,5‐triazine‐2,4‐diamino (pzta)‐based Cu(II) complexes, namely [Cu(l ‐Val)(pzta)(H2O)]ClO4 ( 1 ) and [Cu(l ‐Thr)(pzta)(H2O)]ClO4 ( 2 ) (l ‐Val: l ‐valinate; l ‐Thr: l ‐threoninate), were synthesized and characterized using elemental analyses, molar conductance measurements, spectroscopic methods and single‐crystal X‐ray diffraction. The results indicated that the molecular structures of the complexes are five‐coordinated and show a distorted square‐pyramidal geometry, in which the central copper ions are coordinated to N,N atoms of pzta and N,O atoms of amino acids. The interactions of the complexes with DNA were investigated using electronic absorption, competitive fluorescence titration, circular dichroism and viscosity measurements. These studies confirmed that the complexes bind to DNA through a groove binding mode with certain affinities (Kb = 4.71 × 103 and 1.98 × 103 M?1 for 1 and 2 , respectively). The human serum albumin (HSA) binding properties of the complexes were also evaluated using fluorescence and synchronous fluorescence spectroscopies, indicating that the complexes could quench the intrinsic fluorescence of HSA in a static quenching process. The relevant thermodynamic parameters revealed the involvement of van der Waals forces and hydrogen bonds in the formation of complex–HSA systems. Finally, molecular docking technology was also used to further verify the interactions of the complexes with DNA/HSA. 相似文献
46.
《应用有机金属化学》2018,32(5)
Hierarchical IRMOF‐3 nanosheets were firstly fabricated by a simple reflux strategy and were then characterized through Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and X‐ray photoelectron spectroscopy. They revealed a high fluorescence quantum yield (13.2%) and showed excellent selectivity and sensitivity for 2,4,6‐trinitrophenol (TNP) over a concentration range of 1–29 μM in aqueous solution. This work demonstrates that the facile fabrication method for hierarchical IRMOF‐3 nanosheets with favorable selectivity and sensitivity for TNP could produce a new point of view on novel metal–organic framework nanomaterials for on‐line detection of organic pollutants in water. 相似文献
47.
Dr. Ping Yin Prof. Dr. Jiaheng Zhang Dr. Gregory H. Imler Dr. Damon A. Parrish Prof. Dr. Jean'ne M. Shreeve 《Angewandte Chemie (International ed. in English)》2017,56(30):8834-8838
A new fused N-heterocyclic framework, dipyrazolo-1,3,5-triazinane, was synthesized and the physiochemical properties of its derivatives were investigated to evaluate the integrated energetic performance. In contrast to 1,3,5-trinitro-1,3,5-triazinane (RDX) featuring a distorted chair confirmation, polynitro-functionalized dipyrazolo-1,3,5-triazinanes have nearly planar backbones, thereby enhancing the density and thermal stability. Among these new energetic tricyclic compounds, 5 a and 12 show favorable crystal densities of 1.937 g cm−3 and 1.990 g cm−3 at 150 K, respectively, which rank highest in triazinane-based energetic compounds. Additionally, this synthetic approach was carried out to form seven-membered and eight-membered rings, giving rise to tetranitro dipyrazolo-1,3,5-triazepane ( 5 b ) and tetranitro dipyrazolo-1,3,5-triazocane ( 5 c ), respectively. 相似文献
48.
Raoudha Abderrahim Khaled Boujlel 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):995-999
The imidates derived from 3-aminotriazole 1 react with isocyanates and isothiocyanates to give corresponding 1,2,4-triazolo-1,3,5-triazin-4-ones and 1,2,4-triazolo-1,3,5-triazin-4-thiones in a 60–75% overall yield. If the condensation is realized at r.t., then the intermediate 2 can be isolated. 相似文献
49.
Amit C. Patel Dharmesh H. Mahajan Kishor H. Chikhalia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):368-376
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. 相似文献
50.
Raoudha Abderrahim 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):581-585
The reaction of ethyl chloroformate with iminoesters derived from 3-aminotriazole, followed by amine or phenyl hydrazine condensation, leads to a variety of 1,2,4-triazolo-1,3,5-triazin-4-ones in a 60–85% overall yield. 相似文献