[Structure revision of triptophenolide].

A diterpenoid-lactone, white thin crystals, C20H24O3, m/z: 312 (M+), mp 222-223 degrees C, UV lambda max (EtOH) 217 (log epsilon 4.36) nm, has been isolated from the ethyl acetate extract of the roots of Tripterygium wilfordii Hook. f., in a yield of 0.025%. Its structure was elucidated by spectral analysis (UV, IR, MS, 1HNMR and 13CNMR) and X-ray SCD. It is the known triptophenolide with revision of structure. Triptophenlolide was shown to have obvious inhibiting effects on lymphocyte and IgG (P less than 0.01) when mice and rats were given ig 1.5 mg/kg. The total complements in blood serum was increased. When BALB/C mice were given ig 1.5 mg/kg, the ear oedema induced by dimethyl benzene was significantly inhibited (P less than 0.01); The ear oedema induced by croton oil in SD rats at a dose of ig 1.0 mg/kg was also significantly inhibited (P less than 0.05). The vitamin C content of the adrenal gland was reduced in mice at a dose of 1.5 mg/kg. The ig LD50 of triptophenolide was greater than 30 mg/kg.