New sesquiterpene lactones from Laurus nobilis leaves as inhibitors of nitric oxide production

Dipartimento di Chimica delle Sostanze Naturali, Università degli Studi di Napoli Federico II, Napoli, Italy.
Planta Medica (Impact Factor: 2.34). 09/2005; 71(8):706-10. DOI: 10.1055/s-2005-864191
Source: PubMed

ABSTRACT Two new metabolites 5alphaH,7alphaH-eudesman-4alpha,6alpha,11,12-tetraol (1) and 1beta,15-dihydroxy-5alphaH,7alphaH-eudesma-3,11(13)-dien-12,6alpha-olide ( 2) have been isolated from the methanolic extract of Laurus nobilis L. leaves. Their structures were determined through analysis of their one- and two-dimensional NMR spectral data ((1)H- and (13)C-NMR, DEPT, COSY, HMQC, HMBC and ROESY). The relative stereochemistry is proposed on the basis of combined J-based configuration analysis and ROESY data. In addition, three known sesquiterpene lactones santamarine (3), reynosin (4) and costunolide (5) along with blumenol C (6) were isolated and identified by spectral means. The isolated compounds 1 - 6 were found to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophages. The most active compound 2 potently inhibited NO (2)(-) release with an IC (50) value of 0.8 microM.

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