Soc. Bras. Química 0103 -5053 $6.00+0.00 trypanocidal activity in compounds with an imidazole or oxazole ring linked to a naphthopyrane structure. Two naphthoimidazoles presented higher activities (14.5x and 34.8x) than the standard crystal violet. Emphasis is given to the biodiversity of the Brazilian flora as a starting point for the development of an autonomous and creative medicinal chemistry.

The biological activities of the naphthoquinones lapachol and its cyclization product beta-lapachone, extracted from trees of the genus Tabebuia, have been intensively studied. Given continuity to the studies about heterocyclic derivatives obtained from the reaction of these naphtoquinones with amino-containing reagents, 22 derivatives of beta-lapachone, nor-beta-lapachone and lapachol were synthesised and their activities against trypomastigote forms of T. cruzi were evaluated. The compounds were grouped as oxazolic, imidazolic, phenoxazinic, indolic, pyranic and cyclopentenic derivatives. The variability of the new structures is based on the great electrophilicity of 1,2-quinoidal carbonyls towards reagents containing nitrogen or carbon as nucleophilic centres. In relation to the trypanocidal activity of the synthesised compounds, in view of their structural diversity, tendencies only could be verified. Among the cyclofunctionalised products the oxazolic and imidazolic derivatives showed +/- 1.5 to 34.8 times higher activity than crystal violet, the standard drug for the sterilization of stored blood. These results corroborate the tendency of trypanocidal activity in imidazolic skeletons, and indicate that this moiety could be used as a guide for architectural delineation of molecules with potential value for the chemotherapy of Chagas disease.

Chemical Reactivity Studies with Naphthoquinones from Tabebuia with Anti-trypanosomal Efficacy -[synthesis and trypanocidal activity of fused derivatives such as (III) and (IV) (22 examples) of β-lapachone (IIb), nor-β-lapachone (IIa) and lapachol (I)]. -(PINTO, CLEVERSON NEVES; DANTAS, ANDREA P.; DE MOURA, KELLY C. G.; EMERY, FLAVIO S.; POLEQUEVITCH, PEPITA F.; PINTO, MARIA DO CARMO F. R.; DE CASTRO, SOLANGE L.; PINTO, ANTONIO V.; Arzneim.

organic chemistry, review organic chemistry, review Z 0200 44 -270 Trypanocidal Activity of Isolated Naphthoquinones from Tabebuia and Some Heterocyclic Derivatives: Review from an Interdisciplinary Study -[98 refs.]. -(DE MOURA, KELLY C. G.; EMERY, FLAVIO S.; NEVES-PINTO, CLEVERSON; PINTO, MARIA DO CARMO F. R.; DANTAS, ANDREA P.; SALOMAO, KELLY; DE CASTRO, SOLANGE L.; PINTO, ANTONIO V.; J. Braz. Chem. Soc. 12 (2001) 3, 325-338; Dep. Nucl. Pesquisa Prod. Nat., Univ. Fed. Rio de Janeiro,