Isoscoparins R and S, two new ent-clerodane diterpenoids from Isodon scoparius

Two new ent-clerodane diterpenoids, named isoscoparins R and S (1 and 2), were isolated from the aerial parts of Isodon scoparius. Their structures were characterized mainly by analyzing the NMR and HRESIMS data, and the relative configuration of compound 1 was determined by single-crystal X-ray diffraction. Compound 2 showed weak activity as an autophagic inhibitor.