dc.description.abstract | Raphionacme vignei E. A. Bruce (Apocynaceae) is a plant of the traditional African pharmacopoeia,
whose parts are used in the treatment of various pathologies. Water-soaked R. vignei tubers are
edible. The objective of this study was to isolate triterpenoids from the acetonic extract of R. vignei
tubers, evaluate the analgesic and anti-inflammatory activities of each molecule. The isolated
compounds, characterized by NMR and mass spectrometry, is composed of six triterpenoids: beta-amyrin dodecanoate 1(DDQ1), lupeol dodecanoate 2(DDQ2), beta-amyrin acetate
3(DDQ3), lupeol acetate 4(DDQ4), lupeol 5 (DDQ5) and β-sitosterol 6(DDQ6). These
molecules (DDQ2, DDQ3, DDQ4, DDQ5, DDQ6) are anti-inflammatory in carrageenan
induced rat paw edema, with better anti-inflammatory power for DDQ2 and DDQ4, which would
be related to the presence of acetate function and cycle E. DDQ2 and DDQ4 are also analgesic
in acetic acid induced contortions and the removal test of rat tail on the heating plate. The
analgesic action of DDQ2 and DDQ4, superior to that salicylic acetyl acid, identical to that
morphine, suggests a central action of these two molecules. The potent analgesic effect of DDQ2
and DDQ4, could be attributed to the presence of cyclopentane and isoprene substitution in
position 19 of the lupane family. DDQ2 and DDQ4 represent a potential for the synthesis of
structural analogues with analgesic and/or anti-inflammatory properties. | en_US |