Britannilactone diacetate (1,6-O,O-Diacetylbritannilactone; Compound 2) exhibits potential NO inhibition effect. Britannilactone diacetate exhibits activity against NO production induced by LPS in BV-2 microglial cells with the EC50 value of 6.3 μM. Britannilactone diacetate exhibits a favorable blood-brain barriers (BBB) penetration and absorption, distribution, metabolism, excretion, and toxicity (ADMET) property.