Three new alkaloids (1-3) and a new natural alkaloid (4), named (1'R,3'R,4'R,6'S)-endocycliomurrayamine-A (1), 3-formyle-7-hydroxy-9H-carbazole-1-O-beta-D-glucopyranoside (2), 4'-hydroxyphenyl-6-ethyl-1H-pyrrole-2-carboxaldehyde (3), and 4-hydroxyphenoxy-N-methyl-propanamide (4), together with thirteen known alkaloid derivatives (5-17) were isolated from Murraya koenigii. Among them, compounds (8-17) were isolated from this plant for the first time. The structures of compounds (1-17) were elucidated on the basis of their spectroscopic analysis and references. Compounds 1, 15, 16, and 17 (10 mu M) showed moderate hepatoprotective activities against D-galactosamine-induced HL-7702 cells damage. Compounds 2, 3, 9, and 13 showed moderate activation of PPAR alpha and PPAR gamma receptors.