Aim: To study chemical constituents of Knoxia valerianoides Thorel et Pitard.
Methods: Chromatographic methods were used for the isolation and purification. Structures was elucidated on the basis of chemical analysis and spectroscopic data.
Results: Two anthraquinone were isolated from Knoxia valerianoides Thorel et Pitard and identified as 1,3,5-trihydroxy-2-ethoxymethyl-6-methoxyl-anthraquinone (I) and 1,3-dihydroxy-2-ethoxymethyl-anthraquinone (II).
Conclusion: The compound I was found to be a novel anthraquinone constituent and II was isolated from Knoxia valerianoides Thorel et Pitard for the first time.