Results 31 to 40 of about 848 (152)

Microwave Assisted Synthesis of Novel Functionalized Hydantoin Derivatives and Their Conversion to 5-(Z) Arylidene-4H-imidazoles

Molecules, 2011
2-(Alkyl-1-yl)-1H-imidazol-5(4H)-ones 5a–n were synthesized via nucleophilic substitution of the methylsulfanyl group of the corresponding 2-(methylthio)-1H-imidazol-5(4H)-ones 3a–c with suitably substituted secondary amines.
Edward R. Biehl, Haribabu Ankati, Sukanta Kamila   +2 more
doaj   +1 more source

Effect of Microwave Irradiation on the Condensation of 6-Substituted 3-Formylchromones with Some Five-membered Heterocyclic Compounds

Molecules, 2000
Different types of 3-substituted 4H-4-oxobenzopyrans were prepared by microwave irradiation as well as by a classical method. The beneficial effect of microwave irradiation on the aldol condensation of 3-formylchromones with 2-imino-1-methylimidazolidine-
Nada Pronayova, Tibor Liptay, Dusan Loos, Renata Gasparova, Margita Lacova   +4 more
doaj   +1 more source

Chemical Reactivity of 2-Thiohydantoin Derivatives

Zeitschrift für Naturforschung B, 1977
Treatment of 5-arylazo-2-thiohydantoins (2 a-c) with formaldehyde and the appropriate amine in ethyl alcohol led to the formation of the corresponding Mannich bases 3a-i. 2 a-c reacted with methyl bromoacetate and/or chloroacetic acid to give the esters 5 a-c and/or the free acids 5d-f, respectively. 5e also obtained by treating 5 b with aqueous sodium
A. F. A. Shalaby, H. A. Daboun, M. A. Abdel Aziz   +2 more
openaire   +1 more source

Chemo- and Regioselective 1,3-Dipolar Cycloaddition of Nitrile Imines to 5-Arylmethylene-2-methylthiohydantoins

Organics
1,3-Dipolar cycloaddition reactions of nitrile imines are a powerful tool for the construction of spirocyclic frameworks, yet controlling chemoselectivity remains challenging when dipolarophiles contain multiple reactive sites.
Maria E. Filkina, Lev A. Lintsov, Victor A. Tafeenko, Maxim E. Kukushkin, Elena K. Beloglazkina   +4 more
doaj   +1 more source

Facile regiodivergent synthesis of spiro pyrrole-substituted pseudothiohydantoins and thiohydantoins via reaction of [e]-fused 1H-pyrrole-2,3-diones with thiourea

Beilstein Journal of Organic Chemistry, 2019
A highly divergent synthesis of regioisomeric thiohydantoins and pseudothiohydantoins spiro-fused to a pharmacologically valuable pyrrole-2-one fragment involving the reaction of [e]-fused 1H-pyrrole-2,3-diones with thioureas was developed.
Aleksandr I. Kobelev, Nikita A. Tretyakov, Ekaterina E. Stepanova, Maksim V. Dmitriev, Michael Rubin, Andrey N. Maslivets   +5 more
doaj   +1 more source

Design, synthesis and evaluation of anticancer activity of novel 2-thioxoimidazolidin-4-one derivatives bearing pyrazole, triazole and benzoxazole moieties

Chemistry Central Journal, 2018
A novel series of substituted 2-thiohydantoin incorporated with benzoimidazole, pyrazole, triazole and/or benzoxazole moieties has been synthesized using (E)-3-[1-(4-bromophenyl)ethylideneamino]-2-thioxoimidazolidin-4-one 1 as the key starting material ...
Heba A. Elhady, Refat El-Sayed, Hamedah S. Al-nathali   +2 more
doaj   +1 more source

Advances in Chemistry of Isothiocyanate-derived Colourants

Czech Journal of Food Sciences, 2009
This study is focused on the reactions of isothiocyanates (ITCs) in the presence of amino compounds leading to coloured structures via substituted 2-thiohydantoins.
K. Cejpek, J. Velíšek
doaj   +1 more source

Dietary Ergothioneine as a Novel Anti‐Aging Nutraceutical: Mechanisms, Bioavailability, and Future Perspectives

Food Frontiers, Volume 7, Issue 3, May 2026.
ABSTRACT Ergothioneine (EGT), a natural thiol derivative, has gained attention as a geroprotective nutraceutical. Preclinical research shows EGT scavenges free radicals, maintains mitochondrial integrity, slows telomere erosion, and regulates proteostasis via autophagy and senescent cell clearance.
Tian‐Tian Tian, Liang Chen, Zhen‐Zhen Dong, Chao Yang   +3 more
wiley   +1 more source

Organic-salt-mediated highly regioselective N3-alkylation of 2-thiophenytoin via Michael reaction under solvent-free conditions

Green Chemistry Letters and Reviews, 2016
A regioselective N3-alkylation of 5,5-diphenyl-2-thiohydantoin (2-thiophenytoin) using a very efficient mild base K2CO3 and α,β-unsaturated esters in the presence of organic salt TBAB (tetrabutylammonium bromide) at room temperature has been reported (3b–
Gholamhassan Imanzadeh, Aazam Aliabadi, Mohammadreza Zamanloo   +2 more
doaj   +1 more source

Convenient Synthesis of Thiohydantoins, Imidazole-2-thiones and Imidazo[2,1-b]thiazol-4-iums from Polymer-Supported α-Acylamino Ketones

Molecules, 2018
The preparation of 5-methylene-thiohydantoins using solid-phase synthesis is reported in this paper. After sulfonylation of immobilized Ser (t-Bu)-OH with 4-nitrobenzenesulfonyl chloride followed by alkylation with various bromoketones, the 4-Nos group ...
Petra Králová, Michal Maloň, Hiroyuki Koshino, Miroslav Soural   +3 more
doaj   +1 more source