For the molecule below: 1. Identify all CHIRAL centers if any are present: 2. Name each CHIRAL center (R or S if they exist): COOH HO H H- -OH CH2OH top COOH HO ·H H -OH CH2OH bottom A: NO chiral centers B: One chiral center: R C: One chiral center: S D: Two chiral centers: (top) R and (bottom) S E: Two chiral centers: both RR F: Two chiral centers: (top) S and (bottom) R G: Two chiral centers: both SS IUPAC: https://doi.org/10.1351/goldbook.F02391 A B D E F

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C1: The molecule below is cholesterol. For each of the eight numbered carbons identify whether they are chiral or achiral (write either chiral or achiral as your answer). *** C2: C6: 4 -traini $ HO 03: C7: 2 to DO 3 5 cholesterol % 11 5 C4: C8: 7 ¹4- 8 6 hp Y

Identify the chiral centers in the following molecule and label each as r and s.

H ÇI CH3-C-COOH он CH3-C-CH2Br 1. ČI a b 81. Consider the structures above. Which of these two contains a stereocenter? Draw thestructure on your answer sheet and mark the stereocenter with an asterisk. 82. Which of these two is a chiral molecule? Explain your answer. 83. Which of these two can exist as a pair of enantiomers? 84. Draw the pair of enantiomers using three-dimensional representation.

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For the molecule below: 1. Identify all CHIRAL centers if any are present: 2. Name each CHIRAL center (R or S if they exist): left O A O O B E OF right A: NO chiral centers B: One chiral center: R C: One chiral center: S D: Two chiral centers: (left) R and (right) S E: Two chiral centers: both RR F: Two chiral centers: (left) Sand (right) R G: Two chiral centers: both SS

Identify the chiral centers (mark with *) of the molecule below and assign the absolute configuration of the chiral centers.

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The structure shown below is 3-fluoro-2-butanol. What is the configuration of the chiral centers? A) 25, 3R он CH3 B) 2R, 3S CH3 C) 2R, 3R D) 25, 3S