807-811Three diterpenoids p-benzochinone, labda-14-en-8,13-diol,
coleon U 12-methyl ether, a triterpenoid ursolic acid and two sterols have been
isolated and identified from the roots of
Nepeta clarkei Hook.f. The antioxidant activities of four isolates have also
been determined, of which, coleon U 12-methyl ether and
p-benzochinone have shown good DPPH
scavenging activity with IC50 value 0.045 mg/mL and 0.059 mg/mL,
respectively