CELL DIFFERENTIATION-INDUCING DITERPENES FROM ANDROGRAPHIS-PANICULATANEES

The methanol extract of the aerial part of Andrographis paniculata NEE S showed potent cell differentiation-inducing activity on mouse myeloi d leukemia (M1) cells. From the ethyl acetate-soluble fraction of the methanol extract, six new diterpenoids of ent-labdane type, 14-epi-and rographolide (3), isoandrographolide (4), 14-deoxy-12-methoxyandrograp holide (7), 12-epi-14-deoxy-12-methoxyandrographolide (8), 14-deoxy-12 -hydroxyandrographolide (9) and 14-deoxy-11-hydroxyandrographolide (10 ) as well as two new diterpene glucosides, 14-deoxy-11, 12-didehydroan drographi-side (12) and 6'-acetylneoandrographolide (14), and four new diterpene dimers, bis-andrograpolides A (15), B (16), C (17) and D (1 8), were isolated along with six known compounds. The structures of th e diterpenoids were determined by means of spectral methods. Some of t hese compounds showed potent cell differentiation-inducing activity to wards M1 cells.