In the course of search for potent inhibitors of chitin synthase II from natural resources, seven tannins and related compounds were isolated from the aerial part of Euphorbia pekinensis and identified as gallic acid (1), methyl gallate (2), 3-O-galloyl-(-)-shikimic acid (3), corilagin (4), geraniin
Ten compounds have been isolated from Euphorbia prostrata and identified as gallic acid, corilagin, 1,2,3-tri-O-galloyl-D-glucose,geraniin,tellimagradin I, II, rugosin A, rugosin E, rugosin D and rugosin G on the basis of physicochemical and spectroscopic methods.