Iridoid glycosides from Harpagophytum procumbens D.C. (devil’s claw)

Two iridoid glycosides, harprocumbide A and harprocumbide B were isolated from tubers of Harpagophytum prucumbens D.C., along with nine known iridoid glycosides. One of these compounds displayed marginal inhibition activity against macrophages respiratory burst following chemiluminescence method. Iridoid glycosides, harprocumbide A (6″- O-α- d-galactopyranosylharpagoside, 1) and harprocumbide B (6″- O-( cis- p-coumaroyl)-procumbide, 2) were isolated from the tubers of Harpagophytum prucumbens D.C., along with nine known iridoid glycosides 6- O-α- d-galactopyranosylharpagoside ( 3), and harpagoside ( 4), harpagide ( 5), 8-cinnamoylmyoporoside ( 6), 8- O-feruloylhapagide ( 7), procumbide ( 8), 6″- O-( p-coumaroyl)-procumbide ( 9), 8- O-( p-coumaroyl)-harpagide ( 10) and 8- O-( cis- p-coumaroyl)-harpagide ( 11). Compound 10 showed marginal inhibition activity against macrophages respiratory burst.