A new tertiary tetrahydroisoquinoline alkaloid, methylcorypalline (V) and biscoclaurine base, neferine (II) were isolated from a Formosan lotus embryo (embryo of the seed of Nelumbo nucifera Gaertn.) (Nymphaeaceae), besides the earlier reported isoliensinine (I) and lotusine (IV). Characterization of this new base, methylcorypalline (I), mp. 58–59° (n‐hexane), , by spectral data and direct comparison with synthetic sample prepared from vanillin have proved to be 6,7‐dimethoxy‐2‐methyl‐1,2,3,4‐tetrahydroisoquinoline (V). Methylcorypalline (V) is the first instance occurring in nature having coronary dilator action. Copyright © 1970 The Chemical Society Located in Taipei & Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim, Germany