A new alkaloid derivative of [2]benzopyrano-[3,4-c] indole, isomer of 3-epimacronine, 4-methoxy-5-methyl-1,2,3,5,6,6alphaR-hexahydro-[1,3]dioxolo[4',5':6,7]isochromeno [3,4-c]indol-8-one, has been isolated from Narcissus serotinus L. (Amaryllidaceae) and its structure was elucidated by mass and spectral analysis.