Symmetric Molecules CH3 CH3 COOH COOH H Br Br H H- OH H OH H Br H Br H OH HO H CH3 CH3 COOH COOH meso (±)or(d,l) meso (±)or(d,l) 2,3-dibromobutane tartaric acid Copyright2010 Pearson Prentice Hall,Inc. Erythro and threo are not used on molecules with similar ends. For symmetric molecules,the terms meso and (d,/)are used. Chapter 23 11 Chapter 23 11 Symmetric Molecules ▪ Erythro and threo are not used on molecules with similar ends. ▪ For symmetric molecules, the terms meso and (d,l) are used