From the plant cell suspension cultures of Tauwolfia serpentina Benth., which were cultivated in the alkaloid-production medium after feeding of ajmaline (1), a new indole alkaloid 19- (S)-hydroxy-Nb-methylraumacline (4) was isolated. The structure of 4 first elucidated by spectroscopic analysis was determined by the chemical synthesis from ajmaline (1). © 1992.