3112-31-0Relevant articles and documents
SYNTHESIS OF NEW MACROCYCLIC POLYETHER DI- OR TETRAESTER LIGANDS CONTAINING PYRAZOLE UNITS
Elguero, J.,Navarro, P.,Franco, M. I. Rodriguez
, p. 425 - 428 (1984)
A new series of macrocyclic polyether - diester compounds containing one or two pyrazole rings (NH or N-methyl substituted) have been prepared by treating 3,5-pyrazolyldicarbonyl chlorides with tetraethylene glycol in the presence of triethylamine.Their complexation abilities towards the shift reagent Eu(Fod)3 have been studied by 1H NMR in CDCl3 solution.
Combining 1,2,4-triazole and pyrazole frameworks for new insensitive energetic materials
Chen, Jieyi,Cheng, Guangbin,Dai, Changhao,Tang, Jie,Yang, Hongwei
, p. 17960 - 17965 (2021/10/12)
A new symmetric compound 3,5-bis(3-amine-4H-1,2,4-triazole)-1H-pyrazole and a series of corresponding energetic salts5-9were synthesized. All the new compounds were fully characterized by spectroscopy (IR, NMR, and elemental) analyses and differential scanning calorimetry (DSC). Compound6was further investigated by X-ray crystal-structure analysis. Various performance tests of all the compounds, such as density, thermal behavior, mechanical sensitivity and detonation property, were tested. All the target compounds showed relatively positive calculated heat of formation (24.9 to 2396.4 kJ mol?1), good mechanical sensitivity (IS > 24 J, FS > 280 N) and acceptable detonation property (D> 7400 m s?1,P> 19.5 GPa). In particular, energetic salt9exhibits prominent detonation property (D> 8964 m s?1,P> 37.1 GPa) and excellent sensitivity (IS > 40 J, FS > 360 N), which show its potential application prospects as a new high energy insensitive material.
A new synthetic approach for pyrazolo[1,5-a]pyrazine-4(5H)-one derivatives and their antiproliferative effects on lung adenocarcinoma cell line
Uygun, Meltem Tan,Amudi, Karina,Tura?l?, ?rem Do?an,Menges, Nurettin
, (2021/01/11)
Abstract: Starting from the 3,5-dimethyl pyrazole ring and acetophenone derivatives, five different N-propargylated C-3 substituted pyrazoles were obtained. These derivatives were reacted with different amine derivatives using Cs2CO3 in methanol and 11 different pyrazolo [1,5-a] pyrazine-4(5H)-one derivatives were obtained, which are not found in the literature. The cytotoxic effects of these derivatives in the A549 cell line were investigated. The 160?μM concentration of two derivatives was found to increase cell death rate to 50%, and two derivatives increased cell death rate by up to 40%. The structure–activity relationship (SAR) study revealed an amide group with a long alkyl chain and benzene ring with a p-CF3 group could be important for efficiency. With theoretical ADMET studies of pyrazolopyrazine derivatives, pharmacokinetic phases were predicted to be suitable. Graphic abstract: [Figure not available: see fulltext.].
Strategy for the Synthesis of pyrazolo[5,1-d][1,2,5]triazepinones, a new heterocyclic system
Kharaneko
, p. 1322 - 1325 (2016/10/26)
A preparative procedure has been developed for the synthesis of 4-oxo-7-phenyl-5,8-dihydro-4H-pyrazolo[ 5,1-d][1,2,5]triazepine-2-carbohydrazide, the first representative of a new heterocyclic system, by recyclization of methyl 4-oxo-6-phenyl-4H-pyrazolo[5,1-c][1,4]oxazine-2-carboxylate with hydrazine hydrate.
Synthesis of 3-(5H-pyrazolyl)cyclobutanone derivatives
Fu, Pengfei,Li, Zeqing,Wang, Yuqiang,Yu, Pei
, p. 2545 - 2547 (2015/12/12)
A 3-(5H-pyrazolyl)cyclobutanone derivative was synthesized via two different optimized routes. In the first route, the substitutional pyrazole olefins was prepared as a precursor, the target molecule was synthesized via [2 + 2]-cycloaddition by using pyrazols olefins and ketene in total yield of 3 %. In the second route, the four-member ring cyclobutanone fragment was made first, then the pyrazole ring was obtained through cyclization, offering the target molecule with a yield of 8.6 %.
Efficient photochemical water oxidation by a dinuclear molecular ruthenium complex
Laine, Tanja M.,K?rk?s, Markus D.,Liao, Rong-Zhen,A?kermark, Torbj?rn,Lee, Bao-Lin,Karlsson, Erik A.,Siegbahn, Per E. M.,A?kermark, Bj?rn
supporting information, p. 1862 - 1865 (2015/01/30)
Herein is described the preparation of a dinuclear molecular Ru catalyst for H2O oxidation. The prepared catalyst mediates the photochemical oxidation of H2O with an efficiency comparable to state-of-the-art catalysts.
Experimental and theoretical investigation of the spectroscopic and electronic properties of pyrazolyl ligands
Adeniyi, Adebayo A.,Ajibade, Peter A.
, p. 831 - 845 (2014/07/22)
The electronic and spectroscopic properties of seven pyrazole derivatives are presented in order to give a clear understanding of their distinguishing features. Four out of the seven ligands are synthesised and are also characterised experimentally. A very high correlation was observed between the experimental and the theoretical IR, 1H NMR and 13C NMR, which help in the characterisation of the ligands. The excitation properties computed using the TDDFT shows that most of experimentally observed absorptions of the ligands are predominantly form either the HOMO or HOMO-1 to LUMO or LUMO+1. The characteristic features of the *N atoms (i.e. metal available coordinating centre) shows that the carboxylic unit may possibly decrease the metal affinity of the pyrazole unit while the pyridine unit will increase the affinity. The conductivity properties of the seven ligands are found to be in the order of bdmpzpy > bpzpy > bphpza > bdcpzpy > phpz > dcpz. The J-coupling of *NN can give an insight into the variation in their bond distance, bond stretch and bond strength in the ligands. Also the atomic properties of the *N atoms and their *NN bonds can help in the molecular characterisation, differentiation and in prediction of the non-linear optical properties of the ligands as conductive materials.
Synthesis and Protonation Behavior of 26-Membered Oxaaza and Polyaza Macrocycles Containing Two Heteroaromatic Units of 3,5-Disubstituted Pyrazole or 1-Benzylpyrazole. A Potentiometric and 1H and 13C NMR Study
Aran, Vicente J.,Kumar, Manoj,Molina, Jose,Lamarque, Laurent,Navarro, Pilar,Garcia-Espana, Enrique,Ramirez, Jose A.,Luis, Santiago V.,Escuder, Beatriz
, p. 6135 - 6146 (2007/10/03)
The synthesis and acid-base behavior of two series of 26-membered dioxatetraamine and hexaamine heterocyclophanes containing two nuclei of either pyrazole (4a and 6a) or 1-benzylpyrazole (4b and 6b), respectively, are reported. Dipodal (2 + 2) condensations of 3,5-pyrazoledicarbaldehyde 2a or its 1-benzyl derivative 2b with 1,5-diamino-3-oxapentane afford in both cases the stable Schiff bases 3a,b in 90% yield, which after reduction with NaBH4 gave 4a,b in 75% and 84% yield, respectively. Condensation of 2a with diethylenetriamine leads to a complex mixture containing imidazolidine isomers, which was reduced in situ to afford 6a in 30% yield. Condensation of 2b with the same amine gave the stable diimidazolidine derivative 5b, which after crystallization was isolated as a pure compound in 80% yield and fully identified from analytical and 1H and 13C NMR data as a constitutional isomer with both imidazolidine rings located at the side of the pyrazole closer to the benzylic substituents. Reduction of 5b with NaBH4 afforded the polyamine 6b in 86% yield. Protonation constants of 4a,b and 6a,b have been determined by potentiometric methods in the pH 2-11 range, and their protonation sequences were established by a 1H and 13C NMR study in D2O at variable pH. For each compound, the number of protonation constants equals the number of nitrogens in the side chains. In the pH range studied, the pyrazole rings are not involved in protonation or deprotonation processes.
Synthesis and Characterization of Masked Aminopyrazolecarboxylic Acid Synthons
Lee, Ho H.,Cain, Bruce F.,Denny, William A.,Buckleton, John S.,Clark, George R.
, p. 428 - 431 (2007/10/02)
The synthesis of the masked aminopyrazolecarboxylic acid synthons (11a,b and 12a,b) from pyrazole-3,5-dicarboxylic acid (6) and the determination of their structures by X-ray crystallography are detailed.The compounds are useful for the synthesis of polypyrazolecarboxamides analogous to the DNA minor groove binding antibiotics distamycin A and netropsin.
