Chemical Constituents from Staminate Flowers of Eucommia ulmoides Oliver and Their Anti-Inflammation Activity in Vitro.

Three new monoterpenoids, named eucomylides A - C ( 1 - 3 ), along with six known compounds ( 4 － 9 ) were isolated from the staminate flowers of Eucommia ulmoides Oliver. The structures were elucidated by extensive analyses of spectroscopics methods, and their absolute configurations were established by time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculation. All the compounds along with previously isolated components ( 10 － 14 ) were tested for their anti-inflammatory effects. Two iridoid glycosides ( 11 and 12 ) and a flavonoid glycoside ( 14 ) showed potent suppressive effects on nitric oxide (NO) production in RAW 264.7 cells, with IC 50 values ranging from 17.11 to 22.26 μM.