Two Novel Monoterpene Alkaloid Dimers from Incarvillea arguta

Abstract Two novel monoterpene alkaloid dimers, named argutanes A and B ( 1 and 2 , resp.), together with the known alkaloid boschniakine ( 3 ), were isolated from the roots of Incarvillea arguta. The structures were elucidated on the basis of 1D‐ and 2D‐NMR, as well as HR‐ESI‐MS data.