[Studies on phenanthrene constituents from stems of Dendrobium candidum].

ABSTRACT

OBJECTIVE: To investigate chemical constituents from the stems of Dendrobium candidum. METHODS: The constituents were isolated by various column chromatography methods, and their structures were elucidated by spectral analysis (IR, UV, NMR and MS). RESULTS: Six compounds were isolated from ethanol extract and their structures were identified as 2,3,4,7-tetramethoxyphenanthrene (I), nakaharain (II), 2,5-dihydroxy-3,4-dimethoxyphenanthrene (III), confusarin (IV), nudol (V) and bulbophyllanthrin (VI). CONCLUSION: Among these compounds, compounds II, III, VI are isolated from Dendrobium candidum for the first time.