Buscar
Mostrando ítems 1-10 de 15
Microwave-assisted synthesis of 2-substituted 4,5,6,7-tetrahydro-1,3-thiazepines from 4-aminobutanol
(Beilstein-Institut, 2020-01)
A general procedure for the synthesis of 2-substituted tetrahydro-1,3-thiazepines by MW-assisted cyclization of 4-thioamidobutanols is presented. The acyclic precursors were prepared in high overall yields by an expeditious ...
Synthesis of dihydroquinazolines from 2-aminobenzylamine: N3-aryl derivatives with electron-withdrawing groups
(Beilstein-Institut, 2018-09)
The sequential N-functionalization of 2-aminobenzylamine (2-ABA) followed by cyclodehydration allowed for a straightforward and efficient synthesis of 3,4-dihydroquinazolines with N-aryl substituents bearing electron-withdrawing ...
1,n-diamines. Part 2: Synthesis of acyclic and heterocyclic N-arylputrescine derivatives
(Pergamon-Elsevier Science Ltd, 2011-04)
In the present Letter we report the use of N-arylputrescines as synthetic intermediates for the preparation of N-acyl-N′-aryltetramethylenediamines 3 and related seven-membered heterocyclic amidines 4. Compounds 1 were ...
A suitable synthesis of azlactones (4-benzylidene-2-phenyloxazolin-5-ones and 4-alkylidene-2-phenyloxazolin-5-ones) catalyzed by silica-alumina supported heteropolyacids
(Elsevier Science, 2009-01)
Eleven examples of azlactones (4-benzylidene-2-phenyloxazolin-5-ones and 4-alkylidene-2-phenyloxazolin-5-ones) were prepared via an Erlenmeyer-type synthesis from aromatic aldehydes, hippuric acid and acetic anhydride was ...
1,n-Diamines. Part 4: synthesis of 1-aryl-2-alkyl-1,4,5,6,7,8-hexahydro-1,3-diazocines
(Elsevier, 2011-11)
In this Letter we present the synthesis of hitherto unreported 1-aryl-2-alkyl-1,4,5,6,7,8-hexahydro-1,3-diazocines 1. Cyclic amidines 1 were synthesized by PPSE promoted ring closure of N-acyl-N0-arylpentamethylenediamines ...
1,n-Diamines. Part 3: Microwave-assisted synthesis of N-acyl-N′-arylhexahydropyrimidines and hexahydro-1,3-diazepines
(Pergamon-Elsevier Science Ltd, 2011-10)
In this Letter we present a method for the synthesis of N-acyl-N´-arylhexahydropyrimidines 1, by ring closure of N-acyl-N´-aryl-1,3-propanediamines 3 with formaldehyde. Cyclodehydrations were performed in aqueous medium ...
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis
(Universidade Federal de Santa MariaBrasilQuímicaUFSMPrograma de Pós-Graduação em QuímicaCentro de Ciências Naturais e Exatas, 2017-02-24)
This work first describes the synthesis of the starting materials, the 1,2,4- and 1,3,4-oxadiazoles, from arylamidoximes and arylhydrazides derivatives, respectively. These two precursors were previously reacted with the ...
Synthesis and antifungal activity of bile acid-derived oxazoles
(Elsevier Science Inc, 2016-04)
Peracetylated bile acids (1a-g) were used as starting materials for the preparation of fourteen new derivatives bearing an oxazole moiety in their side chain (6a-g, 8a-g). The key step for the synthetic path was a Dakin-West ...
Mesoporous titania/tungstophosphoric acid composites: suitable synthesis of flavones
(Springer, 2013-08-01)
Mesoporous TiO2/H3PW12O40 composites were synthesized by sol-gel reactions using urea as a low-cost template, and adding tungstophosphoric acid (TPA) at the same time as the template. The TPA concentration was varied in ...
Síntesis de compuestos oxa–heterocíclicos substituídos a partir de dimedona con derivados de benzaldehído
(Universidad Nacional de Trujillo, 2016)