Results 21 to 30 of about 486,719 (268)

Solvent Effects in the Regioselective N-Functionalization of Tautomerizable Heterocycles Catalyzed by Methyl Trifluoromethanesulfonate: A Density Functional Theory Study with Implicit Solvent Model

Computation, 2022
Methyl trifluoromethanesulfonate was found to catalyze the reaction of the nucleophilic substitution of the hydroxyl group of alcohols by N-heterocycles followed by X- to N- alkyl group migration (X = O, S) to obtain N-functionalized benzoxazolone ...
Nelson H. Morgon, Srijit Biswas, Surajit Duari, Aguinaldo R. de Souza   +3 more
doaj   +1 more source

Synthesis and Spectroscopic Characterization of Two Tetrasubstituted Cationic Porphyrin Derivatives

Molecules, 2011
An imidazolium tetrasubstituted cationic porphyrin derivative (the free base and its Zn(II) complex) with five-membered heterocyclic groups in the meso-positions were synthesized using microwave irradiation, and the compounds obtained characterized by 1H-
Newton M. Barbosa Neto, José A.S. Cavaleiro, Antonio E.H. Machado, Rodrigo De Paula, Diesley M.S. Araújo, Hércules S. Miglio, Leonardo T. Ueno, Weverson R. Gomes   +7 more
doaj   +1 more source

Solvent-Mediated Rate Deceleration of Diels–Alder Reactions for Enhanced Selectivity: Quantum Mechanical Insights

Chemistry
Solvents can have a tremendous influence on the rate and selectivity of chemical reactions, but their effects are not always well accounted for. In the present work, density functional theory computations are used to investigate the influence of solvent ...
Umatur Rehman, Asim Mansha, Felix Plasser   +2 more
doaj   +1 more source

Benzoxazole Iminocoumarins as Multifunctional Heterocycles with Optical pH-Sensing and Biological Properties: Experimental, Spectroscopic and Computational Analysis

Chemosensors
A novel series of benzoxazole-derived iminocoumarins was synthesized via a Knoevenagel condensation and fully characterized using NMR, UV–Vis spectroscopy, and computational methods. Their photophysical properties were systematically examined in solvents
Marina Galić, Ana Čikoš, Leentje Persoons, Dirk Daelemans, Karolina Vrandečić, Maja Karnaš, Marijana Hranjec, Robert Vianello   +7 more
doaj   +1 more source

Theoretical Studies on the Electronic Structure Parameters and Reactive Activity of Neu5Gc and Neu5Ac under Food Processing Solvent Environment

Molecules, 2019
The animal product hazard factor N-glycolylneuraminic (Neu5Gc) and brain nutrient substance N-acetylneuraminic acid (Neu5Ac) were studied at the M062X/6-311 + G(d,p) geometry optimization level.
Rui Chang, Bowen Yang, Qiu-Jin Zhu
doaj   +1 more source

Activation of Electrophile/Nucleophile Pair by a Nucleophilic and Electrophilic Solvation in a SNAr Reaction

Frontiers in Chemistry, 2018
Nucleophilic aromatic substitution reactions of 4-chloroquinazoline toward aniline and hydrazine were used as a model system to experimentally show that a substrate bearing heteroatoms on the aromatic ring as substituent is able to establish ...
Bruno Sánchez, Cristian Calderón, Ricardo A. Tapia, Renato Contreras, Paola R. Campodónico   +4 more
doaj   +1 more source

European Standard Clinical Practice Guideline and EXPeRT Recommendations for the Diagnosis and Management of Gastroenteropancreatic Neuroendocrine Neoplasms in Children and Adolescents

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Pediatric gastroenteropancreatic neuroendocrine neoplasms (GEP‐NENs) are extremely rare and clinically heterogeneous. Management has largely been extrapolated from adult practice. This European Standard Clinical Practice Guideline (ESCP), developed by the EXPeRT network in collaboration with adult NEN experts, provides (adult) evidence ...
Michaela Kuhlen, Calogero Virgone, Antje Redlich, Michael Abele, Ricardo Lopez‐Almaraz, Tal Ben‐Ami, Ewa Bien, Gianni Bisogno, Maja Mazic Cesen, Andrea Ferrari, Malgorzata A. Krawczyk, Yves Reguerre, Dominik T. Schneider, Ines B. Brecht, Charlotte Rigaud, Bilgehan Yalcin, Rainer Claus, Christian Vokuhl, Constantin Lapa, Jörg Fuchs, Segolene Hescot, Thomas Walter, Julien Hadoux, Daniel Orbach   +23 more
wiley   +1 more source

Health‐Related Quality of Life and Symptom Severity Among Patients With PIK3CA‐Related Overgrowth Spectrum: A Mixed‐Methods Study to Understand Real‐World Experience With Alpelisib Treatment

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background PIK3CA‐related overgrowth spectrum (PROS) includes several rare overgrowth disorders resulting from somatic gain‐of‐function mutations in PIK3CA. Despite treatment advances, including the recent approval of alpelisib for PROS in the United States, literature detailing the patient experience with PROS is limited.
Vamsi Bollu, Kaitlin LaGasse, Cory D. Saucier, Kimberly Raymond, Miranda Lauher‐Charest, Lauren Crowder, Beilei Cai, Mary Lisha Paul, Denise Adams   +8 more
wiley   +1 more source

Clinical and Biological Features of Response in Resistant Neuroblastoma to 131I‐Metaiodobenzylguanidine Radiotherapy in the Anti‐GD2 Immunotherapy Era

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background 131I‐metaiodobenzylguanidine (131I‐MIBG) radiotherapy is a key treatment for relapsed and refractory (R/R) neuroblastoma (NB). Patients with R/R disease treated in the modern era are increasingly exposed to anti‐GD2 immunotherapy, which exerts selective pressure and may modify both tumor cell state and microenvironment.
Benjamin J. Lerman, Katherine K. Matthay, Fabienne Hollinger, Catriona Black, Ann A. Lazar, Miguel Pampaloni, Steven G. DuBois, Kieuhoa T. Vo   +7 more
wiley   +1 more source

Solvatochromism studies on UV spectra of 4,5-disubstituted-1,2,4-triazoline-3-thiones

Macedonian Journal of Chemistry and Chemical Engineering, 2012
The influence of a series of organic solvents on the UV spectra of investigated 1,2,4-triazoles, was studied by implementing solvatochromic theory.
Vesna B. Dimova, Nada U. Perišić-Janjić   +1 more
doaj   +1 more source