quebrachine

from The Century Dictionary.

• noun A bitter alkaloid, C₂₁H₂₆O₃N₂, found in quebracho-bark. It melts, with decomposition, at 214–216° C. It is very poisonous.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An alkaloid, probably identical to yohimbine, from the quebracho tree