Complete NMR signal assignment of palytoxin and N-acetylpalytoxin

Palytoxin is the second largest-sized natural product that does not contain repeating units such as amino acids or monosaccharides. The molecular form ula of palytoxin is C129H223N3O54 and the molecule contains 64 chiral cente rs. We assigned all hydrogen and carbon NMR signals of palytoxin and N-acet ylpalytoxin using multidimensional Fourier transform techniques. Although t he complete assignment was difficult due to the spectral complexity. advanc es in NMR spectrometry and techniques such as gradient enhancement and 3D F ourier transform have enabled us to completely assign the H-1 and C-13 sign als of palytoxin and also the N-15 signals of N-acetylpalytoxin. This NMR d ata will contribute to further studies of the structure and biosynthetic pa thways of the palytoxin family compounds. including conformational and dyna mic properties of the molecule. (C) 2001 Elsevier Science Ltd. All rights r eserved.