Objective To study on the chemical constituents from Dendrobium huoshanense. Methods The chemical constituents were separated and purified by silica gel, Sephadex LH-20, semi-prepared HPLC and other chromatography techniques. Their structures were elucidated by MS, 1D and 2D NMR spectroscopic data. Results Eleven compounds (1—11) were isolated, and were identified as trans-ferulic acid nonadecyl ester (1), trans-p-hydroxycinnamic acid nonadecyl ester (2), 2,4,7-trihydroxy-9,10-dihydrophenanthrene (3), naringenin (4), 5-hydroxy-3,4′-dimethoxybibenzyl (5), 5-hydroxy-3-methoxybibenzyl (6), dendrogratiol A (7), amoenylin (8), methyl ferulate (9), protocatechuic acid (10), p-hydroxybenzaldehyde (11). At a concentration of 100 μmol/L, compounds 4 and 7 exhibited inhibitory rates of 39.0% and 38.3% against tyrosinase, respectively. Conclusion Compounds 1 and 2 are new compounds, named dendrohuoshanin A and dendrohuoshanin B. Compounds 3, 5, 7—9 were isolated for the first time from this plant. Compound 3 was the first to be separated and purified through phytochemical methods from this plant. Compounds 1, 2, and 9 belong to simple phenylpropanoids, compound 3 is a dihydrophenanthrene, compound 4 is a dihydroflavone, and compounds 5—8 are bibenzyls. Compounds 4 and 7 show potential skin-whitening effects.

Dendrobium huoshanense C. Z. Tang & S. J. Cheng  /  dendrohuoshanin A  /  dendrohuoshanin B  /  2,4,7-trihydroxy-9,10-dihydrophenanthrene  /  5-hydroxy-3,4′-dimethoxybibenzyl  /  dendrogratiol A  /  methyl ferulate