Three novel diarylheptanoids, calyxin a, calyxin b, and 3-epi-calyxin b from a chinese crude drug “yunnan cao kou” (alpinia Blepharocalyx K. Schum.)

Abstract

Three novel diarylheptanoids, calyxin A (1), calyxin B (2) and 3-epi-calyxin B (3), have been isolated from ethanolic extract of seeds of Alpinia blepharocalyx K. Schum. and their structures determined by the use of 2D NMR spectroscopy including NOE and HMBC experiments and chemical analyses. © 1994, The Pharmaceutical Society of Japan. All rights reserved.