Daphlongeranines A and B, Two Novel Alkaloids Possessing Unprecedented Skeletons from Daphniphyllum longeracemosum

Two novel alkaloids, daphlongeranines A (1) and B (2), with an unprecedented ring system, were isolated from the fruits of Daphniphyllum longeracemosum. Their unique structures and relative stereochemistries were established on the basis of spectroscopic and single-crystal diffraction analysis. The proposed biosynthetic pathway was also discussed. Compounds 1 and 2 showed weak inhibition on platelet aggregation.