Anti-influenza activity of compounds isolated from the leaves of Elsholtzia rugulosa and their chemotaxonomic significance

A phytochemical investigation on the leaves of Elsholtzia rugulosa resulted in the isolation and identification of thirty compounds, including four flavonoids ( 1–4 ), two benzene derivatives, two lignans ( 7 and 8 ), three phenylpropanoids ( 9–11 ), three phenolic acid ( 12–14 ), five sesquiterpenes ( 15–19 ), five nor-sesquiterpenes ( 20–24 ), one diterpenoids ( 25 ), and four monoterpenoids ( 26–30 ). Among of them, compounds 2–8 and 10–30 were firstly reported in the genus Elsholtzia , all compounds were originally obtained from Elsholtzia rugulosa . Furthermore, the anti-H1N1 activities of these compounds were evaluated in vitro. The results showed compounds 1 , 9 , 14 and 29 possessed moderate anti-influenza activity, with the inhibition rates (%) to be 49.69, 59.1, 48.21 and 44.99 at 100 μ g/mL, respectively. The chemotaxonomic significance of these isolated compounds has been discussed. • Thirty compounds were isolated from the leaves of Elsholtzia regulosa Hemsl. • Phytochemicals of Elsholtzia regulosa Hemsl were studied for the first time. • Chemotaxonomic significance of these compounds was discussed. • In vitro anti-H1N1 activities of these compounds were evaluated.