Pyrazole Research Articles

Synergistic Effect of Complexing Agent TAD and Corrosion Inhibitor PZ on BTA Removal in Copper Post-CMP Cleaning

Benzotriazole (BTA) as a common corrosion inhibitor in the chemical mechanical polishing (CMP) process, can effectively protect the copper (Cu) surface, but its organic residues will form a passivation film on the wafer surface to prevent the contact between the cleaning solution and the wafer surface, so the removal of BTA is a major problem in the post-CMP cleaning. In this paper, N,N’-Bis(3-aminopropyl)−1,2-ethanediamine (TAD) and pyrazole (PZ) were used as the main components in the alkaline cleaning solution and fatty alcohol polyoxy ethylene ether (JFCE) was added as an auxiliary surfactant to investigate the removal of BTA. The complexation ability of TAD and the corrosion inhibition ability of PZ were verified by electrochemical experiments, and the reaction sites of the interaction between TAD and Cu surface were analyzed by quantum chemical calculations. Meanwhile, the mechanism of the synergistic removal of BTA by TAD and PZ was investigated by electrochemical methods. The final optimized cleaning solution consisted of 1 mmol L−1 TAD, 0.1 mmol L−1 PZ and 1 wt% JFCE and its good cleaning performance was verified by contact angle measurements, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), which provided guidance for the development of the cleaning solution.

Recent investigation on heterocycles with one nitrogen [piperidine, pyridine and quinoline], two nitrogen [1,3,4-thiadiazole and pyrazole] and three nitrogen [1,2,4-triazole]: a review

Recent investigation on heterocycles with one nitrogen [piperidine, pyridine and quinoline], two nitrogen [1,3,4-thiadiazole and pyrazole] and three nitrogen [1,2,4-triazole]: a review

Aerobic biodegradation of emerging azole contaminants by return activated sludge and enrichment cultures

Azoles are an emerging class of contaminants with a growing ubiquitous presence in the environment. This study investigates the aerobic microbial degradation of four azoles, pyrazole (PA), 1,2,4-triazole (TA), benzotriazole (BTA) and 5-methylbenzotriazole (5-MBTA), with return activated sludge and microbial enrichment cultures. Slow degradation of PA was observed in the presence of glucose and NH4+ with a peak degradation rate of 0.5 mg d-1 gVSS-1. TA was found to be highly persistent, with no significant degradation observed in 6–8 months under any incubation condition. In contrast, the benzotriazoles were readily degraded at faster rates in all incubation conditions. The degradation rates observed for BTA and 5-MBTA, when provided as the sole substrates, were 8.1 and 16.5 mg d-1 gVSS-1, respectively. Two enrichment cultures, one degrading BTA and the other degrading 5-MBTA, were developed from the activated sludge. Mass balance studies revealed complete mineralization of 5-MBTA and partial breakdown of BTA by the enrichment cultures. Nocardioides sp. and Pandoraea pnomenusa were the most abundant bacteria in the BTA and 5-MBTA degrading enrichment cultures, respectively. The research shows large differences in the biodegradability of various azoles, ranging from complete mineralization of 5-MBTA to complete persistence for TA.

5-(Trifluoromethyl)pyrazoles by a Regioselective [3+2] Cycloaddition

5-(Trifluoromethyl)pyrazoles by a Regioselective [3+2] Cycloaddition

Строение 1,4-дигидро-1,4-диазоцина с тремя аннелированными пиразольными циклами

Определено строение четырех продуктов, образующихся в процессе взаимодействия лити­ированного N-метилпиразола с изоамилнитритом. Установлено, что один из продуктов реакции представляет собой производное 1,4-диазоцина — конденсированный гетероцикл среднего размера, в котором три пиразольных фрагмента аннелированы к восьми­членному гетероциклу; еще один пиразольный фрагмент расположен в боковой цепи. Такое строение молекулы соединения блокирует превращение восьмичленного гетероцикла в бициклическое производное за счет трансаннулярной реакции.

PH- Metric Studies of Cu (II) Complexes of 3(4-Nitrophenyl)-4-Benzoyl 5(2-Hydroxy-4-Bromo-Phenyl) Pyrazole and 3(4-Chlorophenyl)-4-Benzoyl 5(2-Hydroxy-4-Nitro-Phenyl) Pyrazole

PH- Metric Studies of Cu (II) Complexes of 3(4-Nitrophenyl)-4-Benzoyl 5(2-Hydroxy-4-Bromo-Phenyl) Pyrazole and 3(4-Chlorophenyl)-4-Benzoyl 5(2-Hydroxy-4-Nitro-Phenyl) Pyrazole

Expression of type I collagen in response to Isoniazid exposure is indirect and is facilitated by collateral induction of cytochrome P450 2E1: An in-vitro study.

We wanted to investigate whether Isoniazid (INH) can directly stimulate activation of hepatic stellate cells (HSCs) and enhance production of collagen. Treatment of human hepatic stellate cell line LX2 with or without 5μM INH for 24 to 72 hours was performed to look into content of cytochrome P450 2E1 (CYP2E1), activity of NADPH oxidase (NOX) and intracellular oxidative stress. Protein level as well as mRNA expression of alpha smooth muscle actin (α-SMA) and collagen1A1 (COL1A1) were assessed by western blot and real time PCR. In some experiments pyrazole (PY) was pre-treated to LX2 cells to induce CYP2E1 prior to INH treatment. CYP2E1 level as well as NOX activity was gradually increased with INH treatment in LX2 cells till 72 hours. Following 72 hours of INH exposure, intracellular glutathione (GSH) level was found to be reduced compared to control (p<0.01) and showed expression of α-SMA, indicating activation of HSC. We could not found any change in collagen expression in this experimental study. Pyrazole (PY) pre-treatment to LX2 cells caused significant increase in cellular CYP2E1 content associated with increase of NOX, intracellular reactive oxygen species (ROS), and expression of α-SMA and collagen1 after INH exposure. CYP2E1 is present in insignificant amount in HSCs and INH treatment could not induce collagen expression, although altered cellular oxidant levels was observed. But in LX2 cells when CYP2E1 was over-expressed by PY, INH administration provokes oxidative stress mediated stellate cells activation along with collagen type I expression.

Preparation and imaging of 18F-VUIIS1008 targeting TSPO in rheumatoid arthritis model

Objective To synthesize a novel 18F labeled probe targeting translocator protein (TSPO) ligand 2-(5, 7-diethyl-2-(4-(2-fluoroethoxy)phenyl)pyrazolo[1, 5-a]pyrimidin-3-yl)-N, N-diethylacetamide (VUIIS1008), and evaluate its biodistribution and imaging in rheumatoid arthritis (RA) model. Methods The tosylate substrate was labeled with 18F using a tosyloxy for fluorine nucleophilic aliphatic substitution to obtain 18F-VUIIS1008. The labeling efficiency, radiochemical purity, and stability in vitro were determined. In vitro cellular uptake and competitive binding assay were performed on RAW264.7 macrophage cells. Biodistribution and microPET/CT imaging were investigated on RA mice established by Complete Freund′s Adjuvant. Two-sample t test was used to analyze the data. Results 18F-VUIIS1008 was synthesized with the labeling yield up to (41.00±5.00)%, the radiochemical purity >98.00%, and the specific radioactivity >1.52×108 MBq/mmol. 18F-VUIIS1008 was highly stable with the radiochemical purity >98.00% at 4 h after incubation in mouse serum. In vitro, it also exhibited high specific TSPO binding in RAW264.7 macrophage cells. The uptake ratio was (14.00±0.30)% at 1 h after incubation, and decreased significantly ((4.00±0.70)%; t=12.894, P<0.05) after adding excessive unlabeled VUIIS1008. The half maximal inhibitory concentration (IC50) of 18F-VUIIS1008 binding to TSPO was 0.05 nmol/L in RAW264.7 macrophage cells. In vivo distribution results showed that the uptake of 18F-VUIIS1008 in the left arthritic ankles reached the peak value of (1.33±0.02) percentage activity of injection dose per gram of tissue (%ID/g) at 1 h after injection. The radioactivity ratio of left ankle arthritic tissue to blood (A/B) and to normal muscle (A/M) was 4.40±0.22 and 1.65±0.07 respectively. MicroPET/CT imaging demonstrated that 18F-VUIIS1008 could specifically target and retained in the inflammation site. Conclusion 18F-VUIIS1008 can be easily synthesized with high radiochemical purity and can clearly visualized in RA imaging with low background, suggesting its potential as a novel promising molecular probe targeting TSPO for RA PET imaging. Key words: Membrane transport proteins; Pyrazoles; Pyrimidines; Fluorine radioisotopes; Arthritis, rheumatoid; Positron-emission tomography; Tomography, X-ray computed; Mice

A Review on Brief Study on Heterocyclic Compound and Synthetic Route for the Synthesis of Pyrazole and Thiazole

A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of these heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. This review briefly study on pyrazole and thiazole. Pyrazoles are a novel class of heterocyclic compounds possessing wide variety of application in the agrochemical and pharmaceutical industries. Thiazole is also such an important class of heterocyclic compounds which contains one sulfur atom. This review discuss only on synthetic route for pyrazole and thiazole heterocyclic compounds.

Dipotassium Hydrogenphosphate Assisted Multi-component One-Pot Synthesis of 1,4-Hihydropyrano[2,3-c]pyrazole Derivatives

Dipotassium Hydrogenphosphate Assisted Multi-component One-Pot Synthesis of 1,4-Hihydropyrano[2,3-c]pyrazole Derivatives

Synthesis of New Pyrazoline Derivatives and Its Antimicrobial and Antioxidant Activities

Resistance gained by microorganism to conventional antimicrobial agents has lead to the development of new antimicrobial agents against pathogenic microbes. Chalcones and their derivatives proved to be an important molecular scaffold for the search of new pharmaceutically active molecules. Among the various derivatives of chalcones, synthesis of pyrazolines has gained major attention due to their promising biological activities such as anticancer, antimicrobial, antidepressant, immunosuppressive, anti-inflammatory, etc.1−8 Many studies revealed that incorporation of pyrazole moiety into various heterocyclic ring systems gives worthwhile molecules from the biological point of view.9−11 Several marketed drugs such ascelecoxib12 and rimonabant13 contains pyrazole as their core molecular unit.14,15

Synthesis and Insecticidal Activities of Novel Pyrazole Amides Containing 1,3,4-Oxadiazole Moiety

为了寻找与发现新的活性物质，以杀虫剂吡螨胺为先导化合物，采用活性基团拼接的方法，设计并制备了一系列未见文献报道的新型含1，3，4-噁二唑结构的吡唑酰胺类化合物.通过 1 H NMR， 13 C NMR和元素分析测试确认了目标化合物的结构.初步的生物活性测试结果显示，部分目标化合物表现出较好的杀虫活性.在测试浓度为500 μg/mL时，有5个化合物对粘虫的杀灭活性可达80%~100%，其中4个化合物对粘虫的防治效果与对照药剂唑虫酰胺接近.此外，1-甲基-3-乙基-4-氯- N -{[5-（4-甲基苯基）-1，3，4-噁二唑-2-基]甲基}-1 H -吡唑-5-甲酰胺（ 9g ）在测试浓度为500 μg/mL时对蚜虫的杀死率为100%.

Clinical characteristics of vitreous hemorrhage in gestational diabetic retinopathy

Objective To observe the clinical characteristics of gestational diabetic retinopathy(DR) of 13 pregnants with vitreous hemorrhage. Methods The clinical data of 26 eyes retinopathy with 13 cases of gestational diabetes were retrospectively analyzed.After bilateral eyes were mydriatic by Pyrazole MAO amine compound, ophthalmologist used fundus camera to check bilateral fundus.B ultrasonic was used to examine vitreous hemorrhage and the surfaces of vitreous and retinal. Results In 13 cases, 26 eyes vision were between hand motion-0.6.Sudden vitreous hemorrhage in 13 eyes, accounted for 50.0%(13/26). Among them, the class Ⅰ vitreous hemorrhage in 10 eyes, 76.9%(10/13). Ⅱ, Ⅲ grade vitreous hemorrhage in 2 eyes, 15.4%(2/13). Level Ⅳ vitreous hemorrhage in 1 eye, accounted for 7.7%(1/13).26 eyes were diagnosed with stage IV(early or fiber hyperplasia period) DR.The fundus photography: the size, number of retinal neovascularization were found in 13 eyes without vitreous hemorrhage.Ultrasound confirmed that the 13 eyes vitreous hemorrhage were fresh bleeding, and found 4 eyes with fiber membrane, accounted for 30.8%(4/13). The eyes without vitreous hemorrhage were timely treated by laser, and the eyes with vitreous hemorrhage were treated by stage laser treatment according to the condition of vitreous hemorrhage absorption.Followed up for 4 to 6 months, in a stable condition. Conclusion Obstetrics and gynecology doctors and ophthalmologists should pay attention to pregnancy DR with vitreous hemorrhage.Because they are all early or fiber hyperplasia period.Timely and reasonable laser treatment can prevent permanent damage of visual function. Key words: Vitreous hemorrhage; Diabetes retinopathy; Gestation

Thermal addition of pyrazoles to but-2-enal

Thermal addition of pyrazoles to but-2-enal

Preparation of 1,3,5-Trisubstituted Pyrazoles with Cascade Reaction Catalyzed by Cu between Hydrazonoyl Halide and Terminal Alkynes

末端炔烃在亚铜盐的催化条件下,能够与取代芳基腙酰卤通过亲核取代及加成环化的串联反应生成1,3,5-三取代吡唑衍生物.该方法采用易合成的芳基腙酰卤和末端炔烃作为起始原料,在45℃的加热条件下,以绿色溶剂乙腈和水作为反应介质,高产率、区域专一性地生成1,3,5-三取代吡唑产物.而且该反应不受含活泼氢（羟基、羧基等）取代基的影响,通过该方法制备了17种包含不同类型取代基的吡唑衍生物,可作为1,3,5-三取代吡唑类化合物的通用合成法.

Femtosecond Laser-Induced Breakdown Spectroscopy Studies of Nitropyrazoles: The Effect of Varying Nitro Groups.

The technique of femtosecond laser-induced breakdown spectroscopy (FLIBS) was employed to investigate seven explosive molecules of nitropyrazole in three different atmospheres: ambient air, nitrogen, and argon. The FLIBS data illustrated the presence of molecular emissions of cyanide (CN) violet bands, diatomic carbon (C2) Swan bands, and atomic emission lines of C, H, O, and N. To understand the plasma dynamics, the decay times of molecular and atomic emissions were determined from time-resolved spectral data obtained in three atmospheres: air, argon, and nitrogen. The CN decay time was observed to be longest in air, compared to nitrogen and argon atmospheres, for the molecules pyrazole (PY) and 4-nitropyrazole (4-NPY). In the case of C2 emission, the decay time was observed to be the longest in argon, compared to the air and nitrogen environments, for the molecules PY, 4-NPY, and 1-methyl-3,4,5-trinitropyrazole. The intensities of the CN, C2, C, H, O, and N emission lines and various molecular/atomic intensity ratios such as CN/C2, CN(sum)/C2(sum), CN/C, CN(sum)/C, C2/C, C2(sum)/C, (C2 + C) / CN, (C2(sum) + C)/CN(sum), O/H, O/N, and N/H were also deduced from the LIBS spectra obtained in argon atmosphere. A correlation between the observed decay times and molecular emission intensities with respect to the number of nitro groups, the atmospheric nitrogen content, and the oxygen balance of the molecules was investigated. The relationship among the LIBS signal intensity, the molecular/atomic intensity ratios, and the oxygen balance of these organic explosives was also explored.

Thermal addition of pyrazoles to but-3-enenitrile

Thermal addition of pyrazoles to but-3-enenitrile

Synthesis, Characterization and antimicrobial activity of azole-pyrazolidin-3-one derivatives

Pyrazole derivatives have attracted considerable attention in last decade in view of diverse chemotherapeutic potential including anti-cancer. In the present research work some derivatives of pyrazole, 4-(1H-imidazol-1-yl)-5-phenylpyrazolidin-3-one (4a-g), were synthesized by treating the corresponding hydrazones with base in moderate yields. The synthesized derivatives were characterized by FT-IR, 1H NMR and Mass spectroscopy and screened for in vitro antimicrobial activity. The compounds 4c, 4f and 4g showed significant antimicrobial activities.

ChemInform Abstract: A Fascinating Decade for the Synthesis of 1,2‐Azoles

AbstractReview: most significant advances in the construction of functionalized pyrazoles, isoazoles, and isothiazoles reported in the literature up to 2012; 35 refs.

Spirocyclic and Ring-Expanded Fused Pyrazoles

Key words pyrazoles - ring expansion - sigmatropic rearrangement - spirocycles