4. Assign R,S configurations to the following molecules: (a) Br (b) (c) NH2 H3C-CO2H HO-CO2H CH3 NC--CH3 H H 5. Assign R or S configuration to each chirality center in the following molecules: CH3 HaBr (a) Br (b) (c) CH3 HaCH3 BraH C. H3C H OH H CH3 OH CH3 Which of these compounds are enantiomers, and which are diastereomers?

Assign R/S configuration of all stereocenters.

(a) assign R or S configuration to each chiral center, (b) Which compound are enantiomers? (c) Which compounds are diastereomers?

4A.C Determine if the following compound is chiral or not. Indicate if there is a "meso" compound (use "none" if there is not any). (a) Me Me (d) ОН (e) (f) НО Ме Ме Me Ме Ме Me

Which of the following molecules is/are chiral? CH3 CH3 CH3 H MM H H H CH3 (A) (B) CH3, CH3 C=C H H (D) Select one: a. O b. A&B C. B d. B&C e. A O f. D&B C&D&E g. C CH3 H (E) C H CH3 CH3 (C) OH

Identify the configuration of each chiral center in the following compound: 5 4 10 9 12. 11 14 15 13 In the boxes below, first input the number(s) corresponding to the chiral center(s) in numerical order as a comma separated list with no spaces (e.g., "1,3,4"). Then input the configuration(s) of the chiral center(s) in the same order and format (e.g., "R,S,S"). chiral center location(s): Configuration(s):

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)

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1) Determine the relationship of the following pairs of compounds. Are they identical, enantiomers, diastereomers, constitutional isomers or non-isomeric different compounds? OH OH (a) (c) OH € CH3 H- CH3 H3Cl O₂N Br CH2CH3 H H Br CH3 H3C O₂N H H (d)

Which is the correct assignment of chirality at C2 and C4 of the following molecule?