Consider the stereochemistry of two molecules shown here. CH3 H₂C-N. A CH3 BE The configuration of the chirality center A i ✔ [ Select] S on the left has a total of [Select] R The configuration of the chirality center B is [Select] on the right has a total of [Select] chirality centers. The compound The compound

2. Assign R, S configurations to each indicated chirality center in the molecules below. OH COOH HO H CH₂NH2 CH H₂N H HO HO-C H CH ye yde OH H H HC CH2 H HO CO₂H 3. Consider the structure below to answer the following questions: H3C H ΝΗ H OH a. Assign R or S configuration to each chirality center in the structure above. b. Based on the number of chirality centers, how many stereoisomers are possible for the structure above? C. Will this structure have a meso stereoisomer? Explain your answer.

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For the following molecules, draw all possible stereoisomers using line-angle formulas with wedge/dash notation. Label the stereocenters as R or S. Indicate which ones are enantiomers and which ones are diastereomers. (Remember: there are 2 stereoisomers possible for a molecule with n chiral centers) (A) (B) (C) (1 chiral center) Br OH (2 chiral centers) CI OH CH3 (3 chiral centers)