Solved 4. Identify the following pair of molecules as

CH.CH CHE CHE Page 12 of 12 ， constitutional isomers or no relationship. For every stereocenter， COOH COOH HC -Br H -Br H NCH H-C-NH2 CH2CH2CH3 CH。

diastereomers。

please assign the absolute configuration. (Rand S) CI CH OH CH，OH H -CH H2C H H3C H H -CH3 H H Br Br CH，。

4. Identify the following pair of molecules as identical， enantiomers。