Alguns derivados da ?-Lapachona

Lapachol, a- and b-lapachone are natural naphthoquinones found mainly in trees of the genus Tabebuia. The study of these substances has been stimulated mainly by the diversity of their biological activitys such as: trypanocidal, virucidal and inhibition oftopoisomerase enzymes, among others. In this...

Nível de Acesso:openAccess
Publication Date:2001
Main Author: Bernardes, Bauer de Oliveira lattes
Orientador/a: Ferreira, Aurelio Baird Buarque lattes
Banca: Ferreira, Aur?lio Baird Buarque, Lima, Marco Edilson Freire de, Behrens, Maria das Dores Dutra, Santa?Anna, Carlos Maur?cio Rabello de
Format: Dissertação
Language:por
Published: Universidade Federal Rural do Rio de Janeiro
Programa: Programa de P?s-Gradua??o em Qu?mica
Department: Instituto de Ci?ncias Exatas
Assuntos em Português:
Áreas de Conhecimento:
Online Access:https://tede.ufrrj.br/jspui/handle/jspui/4211
Citação:Bernardes, Bauer de Oliveira. Alguns derivados da ?-Lapachona. 2001. [136 f.]. Disserta??o( Programa de P?s-Gradua??o em Qu?mica) - Universidade Federal Rural do Rio de Janeiro, [Serop?dica-RJ] .
Resumo Português:Lapachol, ?-lapachona e ?-1apachona s?o naftoquinonas naturais encontradas principalmente em ?rvores do g?nero Tabebuia. O estudo destas subst?ncias tem sido motivado principalmente pela diversidade de suas atividades biol?gicas, que incluem a??o tripanomicida, virucida, inibi??o de enzimas topoisomerases entre outras. Neste trabalho estudamos a reatividade das carbonilas da quinona blapachona com variados reagentes na forma??o de: an?is dioxano com derivados do estilbeno via processo fotoqu?mico e tamb?m com enaminas, fenazinas a partir de diaminas; 1,3-dioxal com uso de diazocompostos e ainda acetila??o redutiva com anidrido ac?tico e zinco. Trans-estilbeno, 4,4'-dinitro ou 4,4'-dimet?xi-estilbeno n?o tiveram sucesso nas irradia??es com a b-lapachona, entretanto 2,3-difenil-dioxeno forneceu um produto de cicliza??o (aduto de Sch?nberg) com 86% de rendimento. O composto formado com as enaminas 1-piperidino ou 1-morfolino-cicloexeno n?o foram est?veis. Dentre os diazocompostos testados apenas difenil-diazo-metano forneceu produto. As fenazinas preparadas com etileno-diamina e 5,6-diamino-uracil deram rendimentos razo?veis. A elucida??o estrutural dos produtos e intermedi?rios foi realizada por espectroscopia de IV, E.M., RMN de 1H e de 13C. As t?cnicas de DEPT, correla??o homonuclear 1Hx1H, heteronuclear 1Hx13C foram utilizadas para auxiliar a elucida??o de alguns compostos obtidos. C?lculos de modelagem molecular (AM1) foram realizados para corroborar os resultados obtidos e sugerir a s?ntese racional de novos compostos a partir da b-lapachona
Resumo inglês:Lapachol, a- and b-lapachone are natural naphthoquinones found mainly in trees of the genus Tabebuia. The study of these substances has been stimulated mainly by the diversity of their biological activitys such as: trypanocidal, virucidal and inhibition oftopoisomerase enzymes, among others. In this work we studied the reactivity of the carbonyls of the quinone blapachone with various reagents in the formation of: dioxane rings, with stilbenes derivates through a photochemical process and, thermaly, with enamines; phenazines from 11,2- diamines; 1,3-dioxals from diazocompounds; and also reductive acylation with acetic anhydride and zinc. Trans-stilbene, 4,4'-dinitro- and 4,4'-dimethoxy-stilbene did not cyclize successfully by irradiation with b-lapachone, however, 2,3-di-phenyl-dioxene supplied a cyc?ization product (Sch?nberg adduct) with 86% yield. The compounds formed with enamines 1-piperidine- and 1-morpholine-cyclohexene were partially characterized, but were not stable. Among the diazocompounds tested diphenyl-diazo-methane was the only one to give a 1,3-dioxolone product. From ethylene-diamine and 5,6-diamino-uracil phenazines were prepared in reasonable yields. The structural elucidation of the products and intermediates was accomplished by IR, MS, NMR 1H and of 13C spectroscopies. The techniques of DEPT, homonuclear 1Hx1H and heteronuclear 1Hx13C correlation were used to aid the determination of some stmctures. Molecular modelling calculations (AM1) were perfomed to corroborate the obtained results and to suggest rational synthesis of new compounds from b-lapachone