3 documents found, page 1 of 1
Self-organizing maps in chemotaxonomic studies of Asteraceae: a classification ...
Emerenciano,Vicente P.; Barbosa,Karina O.; Scotti,Marcus T.; Ferreira,Marcelo J.P.Flavonoids have shown good chemical markers for Asteraceae. In this paper, 4,700 occurrences of flavonoids (about 800 compounds) were considered in an expert system developed for taxonomic purposes. Through the use of Self-Organizing Maps (SOM) phylogenetic relationships among the subfamilies and tribes of Asteraceae were established. These taxa were classified on the basis of their occurrences and oxidation pa...
Computer-aided prediction of 125Te and 13C NMR chemical shifts of diorgano tell...
Emerenciano,Vicente P.; Diego,Dennis G.; Ferreira,Marcelo J. P.; Scotti,Marcus T.; Rodrigues,Gilberto V.; Comasseto,João V.This work describes a method to predict the 125Te and 13C NMR chemical shifts of diorgano tellurides based in a three-dimensional approach. For that, a collection of 150 compounds were selected from the literature and had their geometry optimized using the PM3 semi-empirical method. From this data, the structures were coded by the FOCOS program which described the chemical environment for each atom present in t...
SISTAX: an intelligent tool for recovering information on natural products chem...
Alvarenga,Sandra A.V.; Gastmans,Jean P.; Ferreira,Marcelo J. P.; Rodrigues,Gilberto V.; Brant,Antônio J. C.; Emerenciano,Vicente P.This work describes the development of a new program, named SISTAX, for the expert system SISTEMAT. This program allows anyone interested in chemotaxonomy to carry out an intelligent search for organic compounds in databases through chemical structures. When coupled with can efficient encoding system, the program recognizes skeletal types and can find any substructural constraints demanded by the user. An examp...