Current Research

1. Synthesis of Annulenes Through Diels-Alder Reaction

The annulenes in question are compounds of theoretical interest for studies about aromaticity. The main objective of this project is to develop methods for the synthesis of 1,4-Methane[10]annulene.

2. Synthesis of Heliangolides Through Diels-Alder Reaction

Heliangolides are natural products with a polycyclic macrocyclic structure. Several of these compounds show biological activity. A representative example is goyazensolide. The main objective of this project is to develop a synthesis of the macrocyclic structure by breaking bonds of smaller rings.

3. Synthesis of Cuparanes

Cuparanes are terpenic natural products. Their structure contain two neighbouring quaternary centers in a five-membered ring. Microbiotol is an example. The objective is to develop methods that can be applied to several cuparanes.

4. Synthesis of Capsorubin

Capsorubin is a carotenoid, a xanthophyll, found in red peppers. It is a useful product as a natural dye for food industry. The project involves novel methods for the synthesis of both the polyenic chain and the five-membered rings.

5. Synthesis of Compounds from Otoba parvifolia

Several products with similar structures were isolated from the Brazilian plant Otoba parvifolia. Some of these products had biological activity. The example given below is illustrative. The structure looks relatively simple, but the high number of reactive functions close to each other renders the synthesis of these compounds a very complex task.

6. Studies About NMR of Substituted Cyclopentanes

These studies are aimed at the development of analytical techniques for the determination of relative stereochemistry in substituted cyclopentanes.

7. Synthesis of t-Crotonin

t-Crotonin is one of the compounds isolated from Croton cajucara. We are presently studying methods for the synthesis of its structural moyeties, aiming at a total synthesis. Other compounds isolated from the same plant are being studied simultaneously.

8. Conformational Studies in Organic Compounds

Under this topic we realize studies about conformation of organic compounds through computational methods and nuclear magnetic resonance. The main objectives are to develop analytical methods for organic compounds and improve methods for elaboration of organic synthesis projects.

9. Synthesis of Lignan-lactones

Lignans are natural products widely distributed in the plant kingdom. These compounds have several types of structures and attracted much interest on account of their range of biological activities. Arctigenin shows a strong anti-HIV in vitro activity. Podophyllotoxin derivatives are known to have anti-cancer and antiviral activity, antagonist agents for the platelet activating factor and other physiological activities. The synthesis of these products is being studied using an asymmetric hydrogenation as a key reaction with differents types of chiral catalysts.

10. Enantioselective Synthesis of Butyrolactones

Several derivatives of butyrolactones have been isolated and identified as the autoregulators of differentiation and antibiotic biosynthesis in various streptomycetes. "A-Factor" is an autoregulator of cytodifferentiation, isolated from Streptomyces griseus, which induces the production of streptomycin in these strains of bacteria. The aim of this study is to synthesize the optically actives butyrolactones, by using the catalytic asymmetric hydrogenation of unsaturated starting materials with metal complexes as chiral catalysts.