1.
J Nat Prod
; 62(11): 1573-5, 1999 Nov.
Artículo
en Inglés
| MEDLINE
| ID: mdl-10579878
RESUMEN
A new purine derivative, 6-methoxy-7-methyl-8-oxoguanine (1), along with 8-oxoadenine (2) and the human metabolite 3-methylxanthine (3), has been isolated from the ascidian Symplegma rubra collected on the southeastern coastline of Brazil. The structures of the three purines were established by analysis of spectroscopic data.
Asunto(s)
Guanina/análogos & derivados , Urocordados/química , Animales , Brasil , Guanina/química , Guanina/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Espectrofotometría Ultravioleta
2.
J Nat Prod
; 60(7): 729-31, 1997 Jul.
Artículo
en Inglés
| MEDLINE
| ID: mdl-9249981
RESUMEN
A new purine, 1,3-dimethylisoguanine (1), has been isolated from the marine sponge Amphimedon viridis and identified by analysis of spectroscopic data. Compound 1 increased the contractions obtained by transmural electrical stimulation in the guinea pig longitudinal muscle/myenteric plexus in a dose-dependent manner.