New alkaloids from Daphniphyllum calycinum.

Four new alkaloids, 17-hydroxyhomodaphniphyllic acid (1), daphcalycinosidine C (2, a new iridoid alkaloid), yuzurimine E (3), and yuzurimic acid B (4), were isolated from the seeds of Daphniphyllum calycinum. The structures of these Daphniphyllum alkaloids were determined by spectroscopic analysis including mass spectrometry and 2D NMR.