Results 11 to 20 of about 14,631 (192)

Phenolic Compounds in Bacterial Inactivation: A Perspective from Brazil

Antibiotics, 2023
Phenolic compounds are natural substances that are produced through the secondary metabolism of plants, fungi, and bacteria, in addition to being produced by chemical synthesis.
Angélica Correa Kauffmann, Vinicius Silva Castro   +1 more
doaj   +1 more source

Direct δ‐Lactone Synthesis From Free Alcohols via Photoinduced δ‐C(sp3)–H Carbonylation in Flow

Angewandte Chemie, EarlyView.
Herein, we have developed a photo‐flow platform for the δ‐C(sp3)─H carbonylative lactonization of free alcohols with carbon monoxide. The transformation integrates alkoxyl radical generation, selective 1,5‐HAT, CO incorporation, and radical–polar crossover to enable direct access to δ‐lactones from simple alcohol precursors.
Prakash Chandra Tiwari, Runkang Liu, Timothy Noël   +2 more
wiley   +2 more sources

Organocatalysis in Synthesis: L-Proline as an Enantioselective Catalyst in the Synthesis of Pyrans and Thiopyrans

Molecules, 2012
The multicomponent reaction (MCR) of aromatic aldehydes 1 and malononitrile (2) with active methylenes 5a–h in the presence of L-proline produced pyrans and thiopyrans 6a–h stereospecifically and in good yields.
Noura Saad Al-Hokbany, Noha M. Hilmy Elnagdi   +1 more
doaj   +1 more source

Crystal structure of 4-(6-chloro-4-oxo-4H-chromen-3-yl)-2-methylamino-3-nitro-4H,5H-pyrano[3,2-c]chromen-5-one chloroform monosolvate

Acta Crystallographica Section E: Crystallographic Communications, 2015
In the title compound, C23H14Cl4N2O7, the pyran ring has an envelope conformation with the methine C atom as the flap. The chromene rings are almost planar (r.m.s.
Rajamani Raja, Subramani Kandhasamy, Paramasivam T. Perumal, A. SubbiahPandi   +3 more
doaj   +1 more source

Crystal structure of ethyl (2S)-9-methoxy-2-methyl-4-oxo-3,4,5,6-tetrahydro-2H- 2,6-methanobenzo[g][1,3,5]oxadiazocine-11-carboxylate

Acta Crystallographica Section E: Crystallographic Communications, 2015
In the title compound, C15H18N2O5, the methoxyphenyl ring makes a dihedral angle of 84.70 (12)° with the mean plane of the tetrahydropyrimidin-2(1H)-one ring.
A. Dhandapani, S. Manivarman, S. Subashchandrabose, B. Gunasekaran   +3 more
doaj   +1 more source

Diastereoselective synthesis of 3,4-dihydro-2H-pyran-4-carboxamides through an unusual regiospecific quasi-hydrolysis of a cyano group

Beilstein Journal of Organic Chemistry, 2016
An efficient diastereoselective approach for the synthesis of functionalized 3,4-dihydro-2H-pyran-4-carboxamides with variable frame was developed based on the reaction of available 4-oxoalkane-1,1,2,2-tetracarbonitriles (adducts of TCNE and ketones ...
Mikhail Yu. Ievlev, Oleg V. Ershov, Mikhail Yu. Belikov, Angelina G. Milovidova, Viktor A. Tafeenko, Oleg E. Nasakin   +5 more
doaj   +1 more source

The crystal structures of two new coumarin derivatives: 2-(4-{2-[(2-oxo-2H-chromen-4-yl)oxy]acetyl}piperazin-1-yl)acetamide and N-(2,4-dimethoxybenzyl)-2-[(2-oxo-2H-chromen-4-yl)oxy]acetamide

Acta Crystallographica Section E: Crystallographic Communications, 2019
The title compounds, 2-(4-{2-[(2-oxo-2H-chromen-4-yl)oxy]acetyl}piperazin-1-yl)acetamide, C17H19N3O5, (I), and N-(2,4-dimethoxybenzyl)-2-[(2-oxo-2H-chromen-4-yl)oxy]acetamide, C20H19NO6, (II), are new coumarin derivatives.
S. Syed Abuthahir, M. NizamMohideen, V. Viswanathan, M. Govindhan, K. Subramanian   +4 more
doaj   +1 more source

Crystal structure, DFT and Hirshfeld surface analysis of 2-amino-4-(2-chlorophenyl)-7-hydroxy-4H-benzo[1,2-b]pyran-3-carbonitrile

Acta Crystallographica Section E: Crystallographic Communications, 2019
The benzopyran ring of the title compound, C16H11ClN2O2, is planar [maximum deviation = 0.079 (2) Å] and is almost perpendicular to the chlorophenyl ring [dihedral angle = 86.85 (6)°]. In the crystal, N—H...O, O—H...N, C—H...O and C—H...Cl hydrogen bonds
M. Beemarao, S. Silambarasan, A. Jamal Abdul Nasser, M. Purushothaman, K. Ravichandran   +4 more
doaj   +1 more source

Modeling Pyran Formation in the Molybdenum Cofactor: Protonation of Quinoxalyl–Dithiolene Promoting Pyran Cyclization [PDF]

Inorganic Chemistry, 2019
Mononuclear Mo and W enzymes require a unique ligand known as molybdopterin (MPT). This ligand binds the metal through a dithiolene chelate, and the dithiolene bridges a reduced pyranopterin group. Pyran scission and formation have been proposed as a reaction of the MPT ligand that may occur within the enzymes to adjust reactivity at the Mo atom.
Douglas R. Gisewhite, Alexandra L. Nagelski, Daniel C. Cummins, Glenn P. A. Yap, Sharon J. N. Burgmayer   +4 more
openaire   +2 more sources

The Search for Natural Inhibitors of Biofilm Formation and the Activity of the Autoinductor C6-AHL in Klebsiella pneumoniae ATCC 13884

Biomolecules, 2019
Human nosocomial infections are common around the world. One of the main causes is the bacteria Klebsiella pneumoniae, which shows high rates of resistance to antibiotics. Thus, drugs with novel mechanisms of action are needed.
Elizabeth Cadavid, Fernando Echeverri
doaj   +1 more source