Secondary metabolites from L. and their anti-inflammatory and analgesic activities.

A previously unreported secoiridoid glycoside, cruciatoside () was isolated from the aerial parts of L. along with ten known compounds eustomoside (), eustomorusside (), gentiopicroside (), 6'--β-D-glucopyranosyl gentiopicroside (), loganic acid (), isoorientin (), isovitexin (), isovitexin 2''ferulate (), mangiferin (), and 2-methyl-inositol (). The chemical structures of the isolates were elucidated based on extensive 1 D and 2 D NMR experiments as well as HRMS analysis. All isolates were evaluated for their anti-inflammatory and analgesic activities. Compounds , , and (200 µM) showed moderate anti-inflammatory activity by inhibiting nitrite production from LPS-induced RAW 264.7 macrophage cells, with the inhibition rates of 39.5%, 25.8% and 22.9% respectively without exhibiting substantial cytotoxicity. Besides, , , , and exerted the highest decrease in IL-6 levels. Moreover, compound showed analgesic activity by decreasing the PGE level comparable to the reference drugs.