Question

2. (16 points total) A naturally occurring amino acid with the formula C,HuNO3 gives the following proton NMR spectrum when run in deuterium oxide with DCI added. The singlet at 5.1 ppm is from 4 protons on three different hetereoatoms merged into a single peak. a. Determine the structure of this amino acid. Draw your answer in the space below b. Fully annotate the NMR spectrum, label ALL peaks. 9 8 7 4 3

Answer 1

From the DBE calculation DBE = 5/hence one (ph ring) and one (-wolt) group are present again in D_2O expt. Data itinolicate that four exchangeable protons are pryont, Hence it has one ph ring one - loolt one - OH one - NH_2/C_7 O_3 H_y N so the molecule B This anometic substitution pattern can be under stood by saing the IH NMR This being a chinal center H_a and H_s are different in nature w.NMR so first H_a & H_b both of them get spited by the nearest proton an a doublet. Then again they (H_a & H_3) split to each other which result doublet of doublet.