Polyoxygenated cyclohexenes from the stems of Uvaria calamistrata.

Nine previously undescribed polyoxygenated cyclohexenes uvacalols L-T (1-9), together with five known analogues (10-14) were obtained from the stems of Uvaria calamistrata. Their structures were established through spectroscopic data analysis, circular dichroism calculations and single-crystal X-ray diffraction. Uvacalols L-N (1-3) are chlorinated analogues. Some compounds were measured for their anti-inflammatory activities through NO generation inhibition in RAW 264.7 cells. Compound 8 had the best inhibitory activity with an IC50 value of 4.49 ± 0.38 μM.