Rate constants for chemical exchange between water and hydroxyl protons innatural compounds evaluated with NMR two-dimensional exchange spectroscopyand geometric average method

Nuclear magnetic resonance two-dimensional exchange spectroscopy has been a pplied to measure the chemical exchange rate constants between water and hy droxyl protons in three natural organic compounds which contain four to eig ht hydroxyl groups. In data treatment, the simple geometric average method has been used. Application of the geometric average method to assumed excha nge systems has indicated that the method is reliable.