Structure, conformation and biological activity studies on rivularin, a new heliangolide isolated from Leptocarpha rivularis

Martínez R.; Carrasco H.; Bustos C.; Kesternich V.; Fernández S.

Abstract

Rivularin, a new heliangolide, was isolated together with leptocarpin as a minor constituent from Leptocarpha rivularis. Structural and conformational studies of this compound were based on elemental analysis. IR spectroscopy, 13C-NMR and 1H-NMR experiments (LIS, NOESY and Py-d 5 spectra). Of the four most probable conformations for rivularin, the preferred one is the TC conformation. The 1H-NMR data were compared with those obtained from the synthetic ?-epimer 11,13-dihydroleptocarpin, prepared by either catalytic hydrogenation or sodium borohydride reduction of leptocarpin, in order to establish the correct structure and conformation in the heliangolide.

Más información

Título de la Revista: BOLETIN DE LA SOCIEDAD CHILENA DE QUIMICA
Volumen: 43
Número: 1
Editorial: Sociedad Chilena de Química
Fecha de publicación: 1998
Página de inicio: 7
Página final: 12
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-0009600958&partnerID=q2rCbXpz