Cyclooxygenase inhibitory properties of nor-neolignans from Styrax pohlii

Abstract

Chemical investigation of the n-hexane and EtOAc fractions of the ethanolic extract from Styrax pohlii (Styracaceae) aerial parts resulted in the isolation of the benzofuran nor-neolignan derivatives egonol (1), homoegonol (2), homoegonol gentiobioside (3), homoegonol glucoside (4) and egonol gentiobioside (5). This is the first report of compounds 1–5 in S. pohlii. Compounds 1–5, the acetyl derivatives 1 a and 2 a, the ethanolic extract (EE), the n-hexane fraction (HF) and EtOAc fraction (EF) were tested for their inhibitory activities against COX-1 and COX-2. The results showed that EE, HF, EF and compounds 1–5 and 1 a–2 a shown weak to moderate inhibition of COX-1 and COX-2. Among the assayed nor-neolignans, 4 gave a COX-1 inhibition of 35.7% at 30 µM. Compound 5 displayed a COX-2 inhibition of 19.7% at 30 µM.

Keywords:

• Styrax pohlii
• Styracaceae
• cyclooxygenase – 1/2 inhibitory activity

Acknowledgements

The authors are grateful to Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for fellowships. FAPESP is also acknowledged for financial support (Grant # 2008/10.283-1).