The new nortriterpene methylene quinones amazoquinone (1) and (7S,8S)- 7-hydroxy-7,8-dihydro-tingenone (2), and the new norphenolic triterpenes 7,8- dihydro-6-oxo-tingenol (3), 23-nor-6-oxo-tingenol (4), and 23-oxo-iso- tingenone (5) were isolated from Maytenus amazonica. Their structures were elucidated by spectroscopic methods. Compounds 1, 2, 3, and 5 showed low antitumor activity against four cancer cell lines.