RESUMO
Two new bromotyrosine alkaloids, tyrokeradines G (1) and H (2), have been isolated from an Okinawan marine sponge of the order Verongida. The structures of 1 and 2 were elucidated on the basis of spectroscopic data. Tyrokeradine G (1) is the first bromotyrosine alkaloid possessing a ß-alanine unit, while tyrokeradine H (2) is a rare bromotyrosine alkaloid possessing a N-substituted pyridinium ring. Tyrokeradines G (1) and H (2) showed antifungal activity.
Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Tirosina/análogos & derivados , Alcaloides/farmacologia , Animais , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Poríferos , Tirosina/química , Tirosina/isolamento & purificação , Tirosina/farmacologiaRESUMO
Four new bromotyrosine alkaloids, tyrokeradines C-F (1-4), have been isolated from Okinawan marine sponges of the order Verongidae. The structures of 1-4 were elucidated on the basis of spectroscopic data. Tyrokeradines C (1) and D (2) are new bromotyrosine alkaloids possesing an imidazole ring, while tyrokeradines E (3) and F (4) are new bromotyrosine alkaloids possesing a cyano group.