Consider the 'H NMR spectrum of a naturally occurring amino acid with the molecular formula of CoHINO, in D:0 solvent with DCl added. In this spectrum, all exchangeable protons give only a single peak at o 5.1 ppm. (ppm) (ppm) (ppm) (a) Determine the structure of this amino acid (general formula: NH;CHRCOOH). (4 marks) (b) Explain the pattem in the range of 6 3.1- 3.4 ppm and determine the coupling constants for the hydrogen atoms involved. (4 marks) (e) Suggest the reason for the observation of only one single peak at & 5.1 ppm for all exchangeable protons. (2 marks) 66996 69 186 IL966