Two isoquinoline alkaloids, (±)-1,2-dimethyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline [(±)-carnegine] and (-)-1,2-dimethyl-6-methoxy-7-hydroxy-1,2,3,4-tetrahydroisoquinoline [(-)-1-methylcorypalline], were isolated from the aerial parts of Arthrocnemum glaucum. Their structures were determined by spectroscopic (UV, IR, MS, 1D and 2D NMR) and also by X-ray analyses. This is the first isolation of these type of alkaloids from this plant and also the first evidence for the presence of the laevo isomer of 1-methylcorypalline in nature. © 1992.