Abstract: Four alkaloids had been isolated from the roots of Rauwolfia yunnanensis Tsiang. Three of them are identified as reserpine, ajmaline and ajmalicine res-pectively by comparing their physical and chemical properties with those of the authentic samples. It seems that the other remained alkaloid is a new compound which has the formula C22H26O4N2 on the elementary analysis of base and it's hydrochloride salf, [α]D+l06' (CHCl3). It should be decomposed by heating without characteristic meltinq point. According to it's IR spectrum it has indole group, hydroxyI group and αβunsaturafed carboxylic metbyl ester and seems to be a serpentine derivative.

Key words: Alkaloids