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981.
Ramesh Kumar Banjare Manoj Kumar Banjare Sandhyarani Panda 《Journal of solution chemistry》2020,49(1):34-51
A comprehensive study the effect of acetonitrile (ACN) with four cationic surfactants, viz. tetradecyltrimethylammonium bromide (TTAB), cetyltrimethylammonium bromide (CTAB), cetylpyridinium chloride (CPC) and cetylpyridinium bromide (CPB) was made by using the conductivity, surface tension, fluorescence and FTIR techniques. Significant micellar, interfacial and thermodynamic properties were studied by the tensiometeric and conductivity methods. The critical micelle concentration (CMC), aggregation number (Nagg), and Stern–Volmer constants (Ksv) have also been studied by the steady state fluorescence method using pyrene as probe. The fluorescence study also supports the CMC results obtained from conductivity and surface tension. FTIR was used to ascertain that the strength of intermolecular interactions such as hydrogen bonding, ion–ion pair interactions and induced dipole interactions between the surfactants and ACN depend upon the head-group of the surfactants. The interaction of surfactants with ACN is energetically favorable and occurs via direct interactions between the surfactants and ACN. The results further revealed that the strength of interactions between the surfactants and ACN follows the order: TTAB > CTAB > CPC > CPB. 相似文献
982.
Joachim W. Heinicke Nidhi Gupta Peter Mayer Konstantin Karaghiosoff 《无机化学与普通化学杂志》2020,646(13):959-963
NH-Functional 1H-1,3-benzazaphospholes 1a–1c and o-chloranil (tetrachloro-o-benzoquinone - TCBQ) undergo rapid [1+4]-cycloaddition in a 1:2 molar ratio to give 2a – 2c as high-melting zwitterionic σ6λ5-phosphorus compounds. In the case of 2a the yield is high (rel. to TCBQ) even if the reactants were used in a 1:0.5 molar ratio. For the 2-tert-butyl-substituted compounds 2b and 2c the yields were significantly lower, in part by unidentified byproducts. Addition of excess TCBQ to crude 2c containing unconverted 1c did not increase but strongly decrease the amount of 2c . Crystallization and XRD analysis led to detection of a minor side or consecutive product 3c , formally corresponding to P=C bond cleavage and [1+4] cycloaddition of three equivalents TCBQ, two at the phosphinidene and one at the carbene end. NMR spectroscopic data of 2a – 2c including conclusive 13C data for 2a give evidence of the structures of the new compounds. 相似文献
983.
Wang Haoran Wasim Akhtar Lalit Mohan Nainwal Sumit Kumar Kaushik Mymoona Akhter Mohammad Shaquiquzzaman Mohammad Mumtaz Alam 《Journal of heterocyclic chemistry》2020,57(9):3350-3360
Thirteen new benzimidazole pendant cyanopyrimidine derivatives were synthesized. The compounds were synthesized through multistep reaction protocol. The structures of synthesized derivatives were studied by EI-MS, 1H NMR, FT-IR and elemental analysis. All the compounds were studied for their anticancer activity at National Cancer Institute. Except compound 7j , all the compounds unveiled cytotoxicity against cancer cells. The most active compound 7a had shown highest value of growth inhibition of 88.44% and 84.19% against HOP-92 and T-47D cancer cell lines. 相似文献
984.
Neha Batra Vinoth Rajendran Ishan Wadi Ankit Lathwal Roshan Kumar Dutta Prahlad C. Ghosh Rinkoo D. Gupta Mahendra Nath 《Journal of heterocyclic chemistry》2020,57(4):1625-1636
A series of benzenesulfonamide-appended [1,2,3]-triazole hybrids was synthesized by using [3 + 2] cycloaddition of primary, secondary, and tertiary sulfonamide azides with various phenoxymethylacetylenes under click reaction conditions. After structural characterization, the compounds were subjected to in-silico absorption, distribution, metabolism, excretion and toxicity (ADMET) screening to evaluate their drug-likeness and other pharmacokinetic parameters. Furthermore, their in vitro antiplasmodial potential was assessed against Plasmodium falciparum (3D7) strain, and some of the synthesized compounds displayed promising antimalarial potency. On cytotoxicity evaluation using MTT cell viability assay, the most active candidate N-(4,6-dimethylpyridin-2-yl)-4-(4-(4-nitrophenoxy)methyl)-1H-[1,2,3]-triazol-1-yl)benzenesulfonamide ( 14 ; IC50 6.2 μg/mL) demonstrated CC50 7.5 μg/mL against human hepatocarcinoma (HUH-7) cells. 相似文献
985.
Anil Kumar Gunthanakkala Madhu Sekhar Mangali Padmavathi Venkatapuram Padmaja Adivireddy 《Journal of heterocyclic chemistry》2020,57(12):4164-4174
A new class of bis(arylsulfonylmethylazolyl)pyridines and bis(arylaminosulfonylmethyl-azolyl)pyridines were synthesized from the synthetic intermediates methyl arylsulfonylacetic acid hydrazide and methyl arylaminosulfonylacetic acid hydrazide adopting a green methodology-ultrasonication. All the synthesized compounds were resulted in higher yield and in shorter reaction times. The spectral parameters such as IR, 1H NMR, 13C NMR, mass and microanalyzes were used to determine the structures of all the synthesized compounds and were assayed for antioxidant activity. The bis(arylaminosulfonylmethylazolyl)pyridines showed higher radical scavenging activity than the bis(arylsulfonylmethylazolyl)pyridines. Besides, unsubstituted, and methyl substituted compounds exhibited greater activity. Among all the tested compounds 8b and 11b were identified as potential antioxidants. 相似文献
986.
Priyanka Sharma Rupesh Kumar Gaurav Bhargava 《Journal of heterocyclic chemistry》2020,57(12):4115-4135
Pyrrolin-4-ones/pyrrolin-3-ones and its derivatives are important heterocyclic systems which are observed in vast variety of natural products, pharmaceuticals, and biologically important compounds. Different researchers all across the world have developed different synthetic methodologies for the construction of functionalized pyrrolin-4-ones/pyrrolin-3-one scaffolds such as the transition-metal catalyzed/mediated cycloisomerizations of 1-aminoynones and dimerization of enaminones or α-diazo-β-oxoamides etc. The present review article summarizes various reports on the synthesis of various simple and functionalized pyrrolin-4-ones/pyrrolin-3-ones from 2000 onward. 相似文献
987.
Abhijit Dutta Amit Kumar Pradhan Fei Qi Paritosh Mondal 《Monatshefte für Chemie / Chemical Monthly》2020,151(2):159-171
Quantum chemical study has been performed on finite-sized bi-metallic Rh3M alloys, M = Ag, Ir, Pd, Pt, Au, derived from magic cluster, Rh4. Bond length of C–O and N–O are noticed to be elongated in the presence of rhodium alloy clusters. CO2 and NO2 gases are found to be highly adsorbed on Rh3M clusters, which is confirmed by stretching frequency of C–O and N–O. DFT evaluated dipole moment and electronic charge redistribution suggests the sensing capability of CO2 and NO2 gases by Rh3M clusters which is further confirmed by the calculated HOMO–LUMO gap. Mixed rhodium alloy clusters supported on single-wall carbon nanotube (SWCNT) exhibits much higher ability to sense CO2 and NO2. On the other hand, SWCNT@Rh3M shows higher catalytic activity for the activation of CO2 and NO2 in comparison to bare Rh3M because of the higher electronic charge redistribution in the case of SWCNT@Rh3M. In case of SWCNT-supported gas adsorbed clusters, p electrons play a major role in bonding. 相似文献
988.
Laxmi Banjare Sant Kumar Verma Akhlesh Kumar Jain Suresh Thareja 《Journal of heterocyclic chemistry》2020,57(9):3483-3492
Aromatase is a crucial enzyme for the catalysis of aromatization reaction at the last and rate-limiting step involved in the conversion of androgenic substrates to an estrogenic substrate. A hormone-dependent breast cancer in postmenopausal woman can be cured by inhibition of estrogen biosynthesis by the help of aromatase inhibitors (AIs). The mode of interactions of flavonones with the active site of aromatase has been studied in search of potent and selective AIs as a substitute of the natural steroidal ligand. Structure-based computational approach namely, molecular docking simulations were performed to investigate the structural features of the docked complex of aromatase and flavonoid ligands. A nonsteroidal flavonoid pharmacophore showing electrostatic and steric features for selective binding within the main pocket of the catalytic active site of aromatase has been identified as an outcome of the study. The binding affinity of quercetin and isoflavone were predicted within aromatase. Isoflavone was used as a negative control to compare its binding affinities with the selected dataset. The predicted binding affinity of negative control isoflavone was in accordance with its in vitro AI efficacy. Isoflavone showed poor binding affinity and ranked last in terms of MolDock score (−86.309 kcal/molÅ) compared to dataset molecules. The generated pharmacophoric information will be helpful for the synthetic chemist to design and synthesize selective AIs with comparable binding affinity to the natural steroidal ligand. 相似文献
989.
Dr. Rakesh Chilivery Dr. Gousia Begum Vahinipathi Chaitanya Dr. Rohit Kumar Rana 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8237-8242
A bio-inspired method is used to render controlled wrinkling surface patterns on supramolecular architectures assembled from polyoxometalate (POM) clusters. It involves a polyamine-multivalent anion interaction generating positively charged coacervates, which while dictating the assembly of POM into spherical structures further facilitate an interesting surface morphogenesis with wrinkling patterns. This spontaneous surface wrinkling depends on the type of multivalent anion and the pH. As the polyamine-anion interaction becomes stronger, the wrinkles turn denser with lesser depth, which eventually undergoes post-buckling to engender a complex surface pattern. Interestingly, the order of influence exerted by different anions on the morphology follows the Hofmeister series. Moreover, the mild synthesis conditions keep the functional POM units dispersed in the sphere with a structural transformability to their lacunary form. 相似文献
990.
Hee-Jeong Cha Se-Yeun Hwang Da-Som Lee Dr. Akula Ravi Kumar Prof. Dr. Yong-Uk Kwon Moritz Voß Eva Schuiten Prof. Dr. Uwe T. Bornscheuer Prof. Dr. Frank Hollmann Prof. Dr. Deok-Kun Oh Prof. Dr. Jin-Byung Park 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7090-7094
Long-chain aliphatic amines such as (S,Z)-heptadec-9-en-7-amine and 9-aminoheptadecane were synthesized from ricinoleic acid and oleic acid, respectively, by whole-cell cascade reactions using the combination of an alcohol dehydrogenase (ADH) from Micrococcus luteus, an engineered amine transaminase from Vibrio fluvialis (Vf-ATA), and a photoactivated decarboxylase from Chlorella variabilis NC64A (Cv-FAP) in a one-pot process. In addition, long chain aliphatic esters such as 10-(heptanoyloxy)dec-8-ene and octylnonanoate were prepared from ricinoleic acid and oleic acid, respectively, by using the combination of the ADH, a Baeyer–Villiger monooxygenase variant from Pseudomonas putida KT2440, and the Cv-FAP. The target compounds were produced at rates of up to 37 U g−1 dry cells with conversions up to 90 %. Therefore, this study contributes to the preparation of industrially relevant long-chain aliphatic chiral amines and esters from renewable fatty acid resources. 相似文献