The title compound of physalin B（C28H32O9）, a main active physalin of Physalis angulata L, was isolated from the whole plant of Physalis angulata L, and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21 with C28H32O9, a = 12.4996（2）, b = 14.35620（10）, c = 14.75190（10）, V = 2607.97（5） 3, Z = 4, Dc = 1.382 mg/cm3, Mr = 542.56, F（000） = 1152, and μ = 0.870 mm-1. The final R = 0.0389 and wR = 0.1037 for 47670 observed reflections（I 〉 2σ（I））. The rigid molecule consists of eight fused rings involving two lactones. There are two C28H32O9 molecules in an symmetric unit, and the title compound is stacked into a 3D layer structure through hydrogen bonds. In the 5~20 μmol/L range, physalin B can significantly inhibit the secretion of inflammatory cytokines TNF-α and IL-6 on RAW264.7 cells. The results suggest that physalin B has anti-inflammatory activity in vitro.
