Several nitrogen-containing derivatives of ursolic acid and oleanolic acid were synthesized ; methyl 3-cyano-3, 4-seco-urs-12-en-28-oate (II), methyl 3b-aza-3a-oxo-A-homo-urs-12-en-28-oate (III), methyl 2, 2-dichloro-3b-aza-3a-oxo-A-homo-urs-12-en-28-oate (IV), methyl pyrazo1o [3, 2-c] olean-12-en-28-oate (VI, VII), methyl 2'-phenyl-2'H-pyrazo1o [3, 2-c] olean-12-en-28-oate (VIII), methyl isoxazo1o [3, 2-c] olean-12-en-28-oate (IX), methyl 2-hydroxy-iminooleanonate (XII), methyl 2, 3-bis (hydroxyimino) olean-12-en-28-oate (XIII), and methyl furazano [2, 3-c] olean-12-en-28-oate (XIV).