Chemical constituents and biological activities of Viburnum macrocephalum f. keteleeri
Three new compounds (1–3) and seven known compounds (4–10) have been isolated from the ethanolic extract of Viburnum macrocephalum f. keteleeri using bioactivity-guided fractionation and identified as methyl (2-α-L-rhamnopyranosyloxy)acetate (1), methyl (2R-3-α-L-rhamnopyranosyloxy)glycerate (2), methyl (3R-4-α-L-rhamnopyranosyloxy-3-hydroxy)butanoate (3), bridelionoside B (4), (6S,7E,9R)-roseoside (5), linarionoside A (6), 3,7,11-trimethyl-1,6-dodecadien-3,10,11-triol (7), (+)-8-hydroxylinalool (8), β-sitosterol (9) and daucosterol (10). The structures of 1–3, including absolute configurations, were determined by spectroscopic data (1H and 13C NMR, HSQC, HMBC and ORD) and chemical methods. In addition, compounds 1–8 were assayed for their insecticidal and antimicrobial activities. Compounds 7 and 8 exhibited moderately insecticidal effects against Mythimna separata with LD50 values of 180 and 230 μg g−1, respectively. Compounds 2, 3, 7 and 8 showed varying antimicrobial activities with IC50 values ranging from 125 to 529 μM.