From the ethanolic extract of the stem of A. esperanzae ethyl and methyl fatty acid esters, fatty acids, aristolochic I and II acids, and β-cubebin were isolated. In addiction asarinin, populifolic and 2-oxo-populifolic acids, aristolactams AIa and AII, and sitosterol 3-O-β-D-glucopyranoside were also isolated and firstly described in the species. Asarinin and β-cubebin showed antibacterial activity against Bacillus cereus and aristolochic acid I against Staphylococcus aureus and Listeria monocitogenes.

A síntese de vários complexos de Pt(II), Pt(0) e Pd(II) com 2-cloro-1,3,2-dioxafosfolana, 2-fluoro-1,3,2-dioxafosfolana, 2-cloro-4,5-benzo-1,3,2-dioxafosfolana, 2-fluoro-4,5-benzo-1,3,2-dioxafosfolana, 2-cloro-1,3,2-dioxafosforinana e 2-fluoro-1,3,2-dioxafosforinana é descrita. Estudos de RMN de 31P{¹H} destes complexos revelam alguns aspectos inexplorados em relação às constantes de acoplamento ¹J(PtP), os quais chamam a atenção para o conceito de ácidos e bases duros e macios. Este trabalho mostra também as diferenças espectroscópicas de RMN de 31P{¹H} entre isômeros cis e trans.

The syntheses of various complexes of Pt(II), Pt(0) and Pd(II) with 2-chloro-1,3,2-dioxaphospholane, 2-fluoro-1,3,2-dioxaphospholane, 2-chloro-4,5-benzo-1,3,2-dioxaphospholane, 2-fluoro-4,5-benzo-1,3,2-dioxaphospholane, 2-chloro-1,3,2-dioxaphosphorinane, 2-fluoro-1,3,2-dioxaphosphorinane are reported. 31P{¹H} NMR studies of these complexes reveals some aspects still unexplored in terms of the magnitude of the coupling constants ¹J(PtP), which brings light to the soft and hard acid-base concept. This work also shows the 31P{¹H} nmr spectroscopic differences between cis and trans isomers.

The synthesis of several mono- and bimetallic platinum and palladium complexes are reported. The monometallic complexes are of the type MCl2(PEt3)2L (L=2-aminothiazol; benzothiazol; 2-imidazolidithione; M=Pt; Pd), and the bimetallic complexes (M2Cl4(PEt3) 2L) are derived from them. Infrared spectroscopic characterization of the monometallic complexes shows that the metal centre are coordinated through the N-endocyclic (L=2-aminothiazol; benzothiazol) and through the sulphur when L=2-imidazolidithione. Coordination of a second metal fragment occurs via the sulphur atom (L=2-aminothiazol; benzothiazol) according to infrared studies. 31P{¹H} NMR spectroscopy suggest that the complexes have a cis- configuration since the ¹J Pt-P are around the value found for this type of compound.