"Coelogyne cristata" contains coeloginanthridin (3,5,7-trihydroxy-1,2-dimethoxy-9,10-dihydrophenanthrene), a 9,10-dihydrophenanthrene derivative, and coeloginanthrin (3,5,7-trihydroxy-1,2-dimethoxyphenanthrene), the corresponding phenanthrene analogue, coelogin and coeloginin.Orchinol and loroglossol have a phytoalexin effect and reduce the growth of "Cattleya aurantiaca" seedlings.