neo ‐Clerodane Diterpenoids from the Aerial Parts of Scutellaria barbata with Anti‐Inflammatory Activity

Abstract The bioactivity‐guided isolation on the Scutellaria barbata extract resulted in the purification of four undescribed neo ‐clerodane diterpenoids, scuttenlines A–D ( 1 – 4 ), alone with 20 known diterpenoids ( 5 – 24 ). The chemical structures of them were elaborated by extensive spectroscopic means, including 1D, 2D‐NMR and HR‐MS. The anti‐inflammatory potential ability of 1 – 24 was screened in lipopolysaccharide‐stimulated mouse RAW 264.7 cells. Scuttenline C (IC 50 =1.9 μM) and 18 (IC 50 =3.7 μM) exhibited potent activity to inhibit NO production.