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heterocyclic amines

S El-Meligie, Azza T Taher, Aliaa M Kamal, A Youssef
A series of chalcone analogous compounds were designed and synthesized. Replacing/substituting the enone or ethylenic bridge of the parent chalcone with rigid heterocyclic moieties or substituted aromatic amines gave nineteen target compounds. Their cytotoxic activities were screened against both breast and liver cancer cells as well as breast and liver normal cells. Target compounds were also evaluated for their inhibition activity of tubulin beta polymerization. Target compound 2e, 3a, 3b, 3c, 4a-4d, 5a, 5b and 6 showed broad spectrum excellent anticancer activity against both MCF-7 and HepG2...
October 1, 2016: European Journal of Medicinal Chemistry
Xiao-Lan Xu, Wen-Tao Xu, Ji-Wei Wu, Jian-Bo He, Hua-Jian Xu
A general and effective method for the synthesis of amides through decarboxylative amidation of α-keto acids with amines has been developed. The reaction proceeded smoothly to afford the corresponding amide products in good yield under air and shows excellent functional group tolerance. In addition, the protocol can be further applied in the synthesis of heterocyclic compounds like benzimidazoles.
October 7, 2016: Organic & Biomolecular Chemistry
Peng Wang, Gen-Cheng Li, Pankaj Jain, Marcus E Farmer, Jian He, Peng-Xiang Shen, Jin-Quan Yu
Meta-C-H amination and meta-C-H alkynylation using a modified norbornene (methyl bicyclo[2.2.1]hept-2-ene-2-carboxylate) as a transient mediator has been developed for the first time. Both the identification of a mono-protected 3-amino-2-hydroxypyridine/pyridone type ligand and the use of methyl bicyclo[2.2.1]hept-2-ene-2-carboxylate as the mediator are crucial for realizing these two unprecedented meta-C-H transformations. A variety of substrates are compatible with both meta-C-H amination and meta-C-H alkynylation...
October 7, 2016: Journal of the American Chemical Society
Pengyuan Ding, Libing Chu, Jianlong Wang
A novel process integrating anaerobic hydrolysis-acidification (HA) and anoxic/oxic (A/O) reactors was developed to treat the actual petrochemical wastewater, which was operated for more than 8 months, the removal efficiency of COD and NH4(+)-N was monitored, and the microbial community was analyzed. The results showed that the effluent concentrations were maintained at around 99 and 1.3 mg/L, with the removal efficiency of 70.6 and 95.4 %, respectively at a total hydraulic retention time (HRT) of 20 h...
October 5, 2016: Applied Microbiology and Biotechnology
Wan-Yun Huang, Shaik Anwar, Kwunmin Chen
The Morita-Baylis-Hillman (MBH) reaction is one of the most useful and efficient protocols for constructing new carbon-carbon bonds between an activated olefin and electrophiles in the presence of a tertiary amine/phosphine. Herein, we present the use of MBH alcohols, which are obtained from the reaction of nitrostyrenes with aldehydes, as well as acetates and amines derived thereof in several organocatalytic transformations. Densely functionalised MBH adducts can also be used to synthesise substituted heteroaromatic compounds, such as furan, pyrrole, pyrazole and imidazole derivatives...
October 4, 2016: Chemical Record: An Official Publication of the Chemical Society of Japan ... [et Al.]
P Raghavaiah, R Kuladeep, D Narayana Rao, A Jyothi Lakshmi, P Srujana, J Subbalakshmi
Heterocyclic building blocks possessing ethylene spacer and amine functionality such as 1-(2-aminoethyl)piperidine (1,2-AEPi), 2-(2-aminoethyl)pyridine (2,2-AEPy) and 1-(2-aminoethyl)pyrrolidine (1,2-AEPr) were reacted with tetracyanoquinodimethane (TCNQ) to give disubstituted compounds namely bis-(1-(2-aminoethyl)piperidino)dicyanoquinodimethane (1), bis-(2-(2-aminoethyl)pyridino)dicyanoquinodimethane (2) and bis-(1-(2-aminoethyl)pyrrolidino)dicyanoquinodimethane (3). Utilization of 1,2-AEPi, 2,2-AEPy and 1,2-AEPr as disubstituents on TCNQ has resulted in interesting crystal structures...
October 1, 2016: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
Jörg Fahrer, Bernd Kaina
Colorectal cancer (CRC) is one of the most frequently diagnosed cancers, which is causally linked to dietary habits, notably the intake of processed and red meat. Processed and red meat contain dietary carcinogens, including heterocyclic aromatic amines (HCAs) and N-nitroso compounds (NOC). NOC are agents that induce various N-methylated DNA adducts and O(6)-methylguanine (O(6)-MeG), which are removed by base excision repair (BER) and O(6)-methylguanine-DNA methyltransferase (MGMT), respectively. HCAs such as the highly mutagenic 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) cause bulky DNA adducts, which are removed from DNA by nucleotide excision repair (NER)...
October 6, 2016: Food and Chemical Toxicology
Zhenda Tan, He Zhao, Changjian Zhou, Huanfeng Jiang, Min Zhang
A new aerobic copper-catalyzed halocyclization reaction of methyl-N-heteroaromatics and aliphatic amines has been developed, which enables straightforward access to functionalized imidazo-fused N-heterocycles with the merits of good functional tolerance, use of easily-available copper salts as the catalysts, lithium halides as the halogen sources and O2 as a sole oxidant. Owing to the reaction features selective introduction of halogen functionalities to the newly formed imidazo-ring, further extensions of the developed chemistry towards synthetic diversity, including effective access to functional materials, are easily envisioned...
October 3, 2016: Journal of Organic Chemistry
Silvia Franchini, Leda Ivanova Manasieva, Claudia Sorbi, Umberto M Battisti, Paola Fossa, Elena Cichero, Nunzio Denora, Rosa Maria Iacobazzi, Antonio Cilia, Lorenza Pirona, Simone Ronsisvalle, Giuseppina Aricò, Livio Brasili
Recently, 1-(1,4-dioxaspiro[4,5]dec-2-ylmethyl)-4-(2-methoxyphenyl)piperazine (1) was reported as a potent 5-HT1AR agonist with a moderate 5-HT1AR selectivity. In an extension of this work a series of derivatives of 1, obtained by combining different heterocyclic rings with a more flexible amine chain, was synthesized and tested for binding affinity and activity at 5-HT1AR and α1 adrenoceptors. The results led to the identification of 14 and 15 as novel 5-HT1AR partial agonists, the first being outstanding for selectivity (5-HT1A/α1d = 80), the latter for potency (pD2 = 9...
September 17, 2016: European Journal of Medicinal Chemistry
Li Zhang, Yang Xia, Baoyun Xia, Keegan J Nicodemus, James McGuffey, Ernest McGahee, Benjamin Blount, Lanqing Wang
Heterocyclic aromatic amines (HCAA) are listed by the US Food and Drug Administration (FDA) as harmful or potentially harmful constituents of tobacco smoke. However, quantifying HCAA exposure is challenging. In this study, we developed a sensitive, precise, and accurate isotope dilution, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantify urinary HCAAs in smokers and nonsmokers. The high-throughput robotic sample preparation system could handle a throughput of over 300 samples per day, while maintaining intra-day and inter-day imprecision and bias ≤10 %...
September 29, 2016: Analytical and Bioanalytical Chemistry
Masashi Sekimoto, Haruna Sumi, Takuomi Hosaka, Takashi Umemura, Akiyoshi Nishikawa, Masakuni Degawa
The ability of nine cooked food-derived heterocyclic aromatic amines (HCAs), such as 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-amino-6-methylpyrido[12-a:3',2'-d]imidazole (Glu-P-1), 2-amino-pyrido[12-a:3',2'-d]imidazole hydrochloride (Glu-P-2), 2-amino-9H-pyrido[2,3-b]indole (AαC), 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC), 2-amino-3-methylimidazo[4,5-f]quinolone (IQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenyl-1H-imidazo[4,5-b]pyridine (PhIP), to activate human aryl hydrocarbon receptor (hAhR) was examined using a HepG2-A10 cell line, which has previously established from human hepatocarcinoma-derived HepG2 cells for use in hAhR-based luciferase reporter gene assays...
September 16, 2016: Food and Chemical Toxicology
Aline Martins de Carvalho, Antonio Anax Falcão de Oliveira, Ana Paula de Melo Loureiro, Gilka Jorge Figaro Gattás, Regina Mara Fisberg, Dirce Maria Marchioni
OBJECTIVE: The aim of this study was to assess the association between protein and arginine from meat intake and oxidative stress in a general population. METHODS: Data came from the Health Survey for Sao Paulo (ISA-Capital), a cross-sectional population-based study in Brazil (N = 549 adults). Food intake was estimated by a 24-h dietary recall. Oxidative stress was estimated by malondialdehyde (MDA) concentration in plasma. Analyses were performed using general linear regression models adjusted for some genetic, lifestyle, and biochemical confounders...
July 26, 2016: Nutrition
S M Afzal, M A N Razvi, Salman A Khan, Osman I Osman, Ahmed H Bakry, Abdullah M Asiri
Novel heterocyclic azomethine dyes were prepared by the reaction of anthracene-9-carbaldehyde with different heterocyclic amines under microwave irradiation. Structures of the azomethine dyes were confirmed by the elemental analysis, mass spectrometry and several spectroscopic techniques. We studied absorbance and fluorescence spectra of the azomethine dyes in various solvents. They are found to be good absorbers and emitters. We also report photophysical properties like, extinction coefficient, oscillator strength, stokes shift and transition dipole moment...
2016: PloS One
Yu-Peng Zhou, Saeed Raoufmoghaddam, Tibor Szilvási, Matthias Driess
The synthesis and structure of the first 1,2-bis(NHSi)-substituted ortho-carborane [(LSi:)C]2 B10 H10 (termed SiCCSi) is reported (NHSi=N-heterocyclic silylene; L=PhC(NtBu)2 ). Its suitability to serve as a reliable bis(silylene) chelating ligand for transition metals is demonstrated by the formation of [SiCCSi]NiBr2 and [SiCCSi]Ni(CO)2 complexes. The CO stretching vibration modes of the latter indicate that the Si(II) atoms in the SiCCSi ligand are even stronger σ donors than the P(III) atoms in phosphines and C(II) atoms in N-heterocyclic carbene (NHC) ligands...
October 4, 2016: Angewandte Chemie
Wim E Van Beek, Joren Van Stappen, Philippe Franck, Kourosch Abbaspour Tehrani
A Cu(I)-catalyzed coupling of a ω-chloro ketone, a primary amine, and an alkyne is described. This protocol allows for the synthesis of α-quaternary carbons in 2-alkynyl-substituted N-heterocycles. The key step is the in situ generation of a cyclic ketiminium species, which has enhanced reactivity for alkynylation compared to acyclic ketiminium species.
October 7, 2016: Organic Letters
S Simonetti, A Díaz Compañy, G Brizuela, A Juan
Silica based materials find applications as excipients and particularly as drug delivery agents for pharmaceutical drugs. Their performance can be crucially affected by surface treatments, as it can modify the adsorption (and release) of these formulations. The role of surface modification on the features of 4-formaminoantipyrine (FAA) adsorbed on β-cristobalite (001) surface is studied by means of simulations based on the Density Functional Theory (DFT). Starting from the results of FAA in interaction with a dehydroxylated surface; a fully hydroxylated surface and a functionalized surface with benzalkonium chloride (BC) surfactant have been added to study the configurational landscape...
September 5, 2016: Colloids and Surfaces. B, Biointerfaces
Dominik Jantke, Lorenz Pardatscher, Markus Drees, Mirza Cokoja, Wolfgang A Herrmann, Fritz E Kühn
The synthesis and characterization of two water-soluble bis-N-heterocyclic carbene (NHC) complexes of rhodium and iridium is presented. Both compounds are active in H2 generation from formic acid and in hydrogenation of bicarbonate to formate. The rhodium derivative is most active in both reactions, reaching a TOF of 39 000 h(-1) and a TON of 449 000 for H2 production. The catalytic hydrogenation reactions were carried out in an autoclave system and analyzed using the integrated peak areas in the (1) H NMR spectra...
October 6, 2016: ChemSusChem
Mahesh P Paudyal, Adeniyi Michael Adebesin, Scott R Burt, Daniel H Ess, Zhiwei Ma, László Kürti, John R Falck
Primary and N-alkyl arylamine motifs are key functional groups in pharmaceuticals, agrochemicals, and functional materials, as well as in bioactive natural products. However, there is a dearth of generally applicable methods for the direct replacement of aryl hydrogens with NH2/NH(alkyl) moieties. Here, we present a mild dirhodium-catalyzed C-H amination for conversion of structurally diverse monocyclic and fused aromatics to the corresponding primary and N-alkyl arylamines using NH2/NH(alkyl)-O-(sulfonyl)hydroxylamines as aminating agents; the relatively weak RSO2O-N bond functions as an internal oxidant...
September 9, 2016: Science
William H Dent, Mark A Pobanz, Chaoxian Geng, Thomas C Sparks, Gerald B Watson, Theodore J Letherer, Kenneth W Beavers, Cathy D Young, Yelena A Adelfinskaya, Ronald R Ross, Greg Whiteker, James Renga
BACKGROUND: Gamma-amino butyric acid (GABA) antagonists are proven targets for control of Lepidopteran and other pests. New heterocyclic compounds with high insecticidal activity were discovered using a competitive-intelligence inspired scaffold hopping approach to generate analogs of fipronil, a known GABA antagonist. These novel aryl heterocyclic amines (AHA's) displayed broad spectrum activity on a number of chewing insect pests. RESULTS: Through >370 modifications of the core AHA structure, a 7-pyrazolopyridine lead molecule was found to exhibit much improved activity on a number of insect pests...
September 8, 2016: Pest Management Science
Maximilian Mimmler, Simon Peter, Alexander Kraus, Svenja Stroh, Teodora Nikolova, Nina Seiwert, Solveig Hasselwander, Carina Neitzel, Jessica Haub, Bernhard H Monien, Petra Nicken, Pablo Steinberg, Jerry W Shay, Bernd Kaina, Jörg Fahrer
PhIP is an abundant heterocyclic aromatic amine (HCA) and important dietary carcinogen. Following metabolic activation, PhIP causes bulky DNA lesions at the C8-position of guanine. Although C8-PhIP-dG adducts are mutagenic, their interference with the DNA replication machinery and the elicited DNA damage response (DDR) have not yet been studied. Here, we analyzed PhIP-triggered replicative stress and elucidated the role of the apical DDR kinases ATR, ATM and DNA-PKcs in the cellular defense response. First, we demonstrate that PhIP induced C8-PhIP-dG adducts and DNA strand breaks...
September 5, 2016: Nucleic Acids Research
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