Structurally diverse steroids with nitric oxide inhibitory activities from Aglaia lawii leaves

Abstract

Eleven previously uncharacterized steroids, along with three analogs were isolated from Aglaia lawii leaves. Their structures were definitely characterized by the methods of NMR, MS, IR, ECD and X-ray crystallography study. Among these unreported compounds, 3-epi-dyscusin C, 3-epi-lansisterone E and (Z)-2α-hydroxyaglawone were C-21 pregnane steroids incorporating a highly oxygenated ring A, while others were Δ⁵-3β-hydroxy-7-ketosteroids bearing different ring D and C-17 aliphatic chains. All isolates were evaluated for nitric oxide (NO) inhibitory activities. 3-Epi-dyscusin C, 3-epi-lansisterone E, (Z)-2α-hydroxyaglawone and 17(20)E-dyscusin B showed significant anti-inflammatory activities with IC₅₀ values of NO inhibition less than 10 μM (in the range from 4.47 ± 0.36 to 7.67 ± 0.46 μM).

Keywords: Aglaia lawii; Anti-inflammatory; Meliaceae; Nitric oxide; Steroids.