CHEM 14C Study Guide - Final Guide: Triglyceride, Fluorine, Ion
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Tyrosine has seven signals, lysine has six, and serine and cysteine each have three. (b) cysteine, tyrosine, serine, and lysine. The given c-nmr data has six signals. (a) yes (b) no (c) yes (d) yes (e) no. X-ray crystallography reveals the positions of atoms in space. Anything which can be proven from these positions can be proven/verified. X-ray crystallography cannot "see" or count electrons, so anything dependent on knowing electron locations cannot be proven. (perhaps implied, but not proven. ) (a) cysteine: london forces only. The cysteine side chain has no polar bonds and no aromaticity. (b) tyrosine: dipole-dipole, hydrogen bonding, pi stacking, london forces. Tyrosine and phenol both lack ions, so anion-cation, ion-dipole, and cation-pi interactions cannot occur. (a) amino acid cysteine cannot be a hydrogen bond donor because the s h bond isn"t polar or because the s h + Chemistry 14c winter 2017 final exam part a solutions page 1.
