Síntese e caracterização de 1,2,4-oxadiazóis e O-glicosídeos 2,3-insaturados inéditos

Detalhes bibliográficos
Ano de defesa: 2012
Autor(a) principal: BARROS, Carlos Jonnatan Pimentel lattes
Orientador(a): FREITAS FILHO, João Rufino de
Banca de defesa: RAMOS, Clécio Souza, MELO, Sebastião José de, SILVA, Ricardo Oliveira da
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal Rural de Pernambuco
Programa de Pós-Graduação: Programa de Pós-Graduação em Química
Departamento: Departamento de Química
País: Brasil
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6317
Resumo: In this work, we drescribed the synthesis and characterization of novel 1,2,4-oxadiazoles and 2,3-unsaturated glycosides, containing heterocyclic ring or terpene units as aglycone. The synthesis of alkyl and arylamidoximes was carried out using two methods: the first was using household microwave irradiation and the second in ultrasound-bath. The alkyl and arylamidoximes 18a-l were obtained with good yields and reduced time for the first two methods compared with the methods found in the literature. The new 1,2,4-oxadiazoles and bis-1,2,4-oxadiazoles were obtained by two methods: at reflux and by microwave irradiation. The 3-aryl-5-pentyl-1,2,4-oxadiazoles (46a-f) were obtained from methyl hexanoate. The bis-1,2,4-oxadiazoles 3,3’-aryl-5,5’-bis-1,2,4-oxadiazolyl propan-2-one (47a-h), 1,2-dihydroxy-1,2-bis [3-aryl-1,2,4-oxadiazol-5-yl]-ethane (48a-h) and 1,2-bis-(3-aryl-1,2,4-oxadiazol-5-yl)ethanol (49a-h) were obtained from the following esters, respectively: diethyl 3-oxoglutarate, dimethyl malate and diethyl tartarate. The novel 2,3-unsaturated O-glycosides were obtained from the Ferrier rearrangement of tri-O-acetyl-D-glucal with alcohols: 2-(3-thienyl)ethanol, citronellol and geraniol. The glycosides were subjected to reactions of basic hydrolysis and allylic oxidation. The structures of the compounds obtained were elucidated by conventional spectroscopic techniques: Infrared and Magnetic Nuclear Resonance 1H and 13C.