Results 31 to 40 of about 1,403,091 (264)

Nitrogen heterocycles from trimethylbenzenes

Heteroatom Chemistry, 2004
AbstractThe reaction between 1,2,4‐trimethylbenzene 1, isobutyric aldehyde, and cyanoacetic ester afforded a mixture of three products: 3,3,5,6,8‐ pentamethyl‐1,2,3,4‐tetraisoquinolylidene‐1‐acetic acid ether (2) and its 3,3,5,6,7‐pentamethyl‐(3)‐ and 3,3,6,7,8‐pentamethyl‐1,2,3,4‐tetraisoquinolyli‐ dene‐1‐acetic acid ether isomers (3) in ratio 1:5:1. ©
Yu. V. Shklyaev, R. R. Ismagilov, Yu. S. Rozhkova, A. A. Fatykhov, I. B. Abdrakhmanov, A. G. Tolstikov, V. M. Dembitsky   +6 more
openaire   +1 more source

Various Synthesis of Imidazo[1,2-a]pyridines Derivatives and Therapeutic Significance: A Review [PDF]

BIO Web of Conferences
The synthesis of bicyclic heterocycles, notably nitrogen-containing imidazopyridines, holds immense appeal due to their structural diversity and pivotal role in biological systems. These compounds are ubiquitously found in nature and are prized for their
Hamdi Abdeljalil, El Hammoudani Yahya, Ahari M’hamed, Amhamdi Hassan, Salhi Amin, El Youssfi Abdellah, El Houssien Akichouh, El Aatiaoui Abdelmalik   +7 more
doaj   +1 more source

Microorganisms in Chemistry of Nitrogenous Heterocycles [PDF]

, 2017
The monograph is devoted to microbiological methods of obtaining organic compounds from a series of nitrogenous heterocycles (azaarenes, quinolones and saturated nitrogenous heterocycles). It is proposed alternative ways of synthesizing compounds that are difficult to obtain using conventional methods of organic chemistry.
openaire   +2 more sources

Atropisomerism in Boron-Nitrogen Heterocycles/Atropisomerism in Boron-Nitrogen Heterocycles

Zeitschrift für Naturforschung B, 1987
Abstract Atropisomerism owing to hindered rotation about the N-aryl bond is observed in 4,5-diethyl-2,2,3-trimethyl-1-(o-trifluormethyl)phenyl-2,5-dihydro-1H-1,2,5-azasila-(2) and -azastanna-boroles (5). The compounds 2 and 5 are characterized by elemental analysis, mass spectra and 1H, 11B, 13 C, 29Si and119Sn NMR.
Roland Köster, Günther Seidel, Susanna Kerschl, Bernd Wrackmeyer   +3 more
openaire   +1 more source

A sustainable thermochemical conversion of animal biomass to N-heterocycles

Journal of Leather Science and Engineering, 2023
The production of high-valued organonitrogen chemicals, especially N-heterocycles, requires artificial N2 fixation accompanied by the consumption of fossil resources.
Yang Tang, Xiao Xiao, Chaojun Zhang, Xiaoling Wang, Junling Guo, Xuepin Liao   +5 more
doaj   +1 more source

Preparation of Antimicrobial Nitrogen Heterocycles Using Sustainable Processes

Proceedings, 2017
Libraries of compounds containing heteroaromatic rings and other nitrogen heterocycles were [...]
Concepción C. González, Jorge Juan Cabrera Trujillo, Emy André-Joyaux, Antonio J. Herrera, Nieves R. Paz   +4 more
doaj   +1 more source

Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides

Beilstein Journal of Organic Chemistry, 2016
This review highlights the biosynthesis of heterocycles in polyketide natural products with a focus on oxygen and nitrogen-containing heterocycles with ring sizes between 3 and 6 atoms.
Franziska Hemmerling, Frank Hahn
doaj   +1 more source

True Closed‐Loop Recyclable Hydrogels Enabled by Imine Boronic Ester Crosslinking

Advanced Materials, EarlyView.
Subtle molecular differences in imine boronic ester crosslinkers profoundly influence hydrogel properties. 2‐formylphenylboronic acid crosslinkers form previously undisclosed 3‐amino‐benzoxaborole heterocycles, enhancing elasticity despite lower crosslinking density compared to their 4‐formylphenylboronic acid counterparts.
Jenna A. King, Joshua M. Litterio, Sean P. Larmore, Steven A. Lopez, Klaus Schmidt‐Rohr, Diego M. Alzate‐Sánchez   +5 more
wiley   +1 more source

Alkylene-functionality in bridged and fused nitrogen-rich poly-cyclic energetic materials: Synthesis, structural diversity and energetic properties

Defence Technology
From the standpoint of chemical structures, the organic backbones of energetic materials can be classified into aromatic rings, nonaromatic rings, and open chains.
Man Xu, Nanxi Xiang, Ping Yin, Qi Lai, Siping Pang   +4 more
doaj   +1 more source

Light Switchable Ionic Conductivity of Arylazopyrazole Modified Polysiloxanes

Advanced Materials Technologies, EarlyView.
We present a polysiloxane functionalized with a novel arylazopyrazole dye that undergoes reversible photoisomerization. Upon lithium bis(trifluoromethanesulfonyl)imide addition and UV irradiation, the polymer exhibits a shift in tan(d) toward higher frequencies and enhanced ionic conductivity.
Malte S. Beccard, Thulasinath Raman Venkatesan, Michael Bauer, Valentin Razvan Lupu, Philipp Scheidegger, Francesco Taddei, Frank A. Nüesch, Dorina M. Opris   +7 more
wiley   +1 more source