Chirality in Biological Systems Chirality is very important in biological systems Enzyme active sites are capable of chiral discrimination Nature(enzymes)is still the best chemist for enantiomerically pure products. The receptor sites for sense of smell can distinguish between enantiomers since: CH CH3 H3C- H -CH3 ℃H2 H2C (+)-carvone (-)-carvone caraway seed spearmint Absolute Configuration The absolute configuration of a molecule is the detailed stereochemical picture including how the atoms are arranged in space. Racemic Mixture (racemate) A mixture is said to be racemic when it contains exactly equal amounts of two enantiomers.Such a mixture is optically inactive (zero rotation of plane polarized light). Racemic mixtures are very common.(The difficult part is to produce exclusively one enantiomer) Ch05 Stereochemistry (landscape) Page 11 Ch05 Stereochemistry (landscape) Page 11 Chirality in Biological Systems Chirality is very important in biological systems. Enzyme active sites are capable of chiral discrimination. Nature (enzymes) is still the best chemist for enantiomerically pure products. The receptor sites for sense of smell can distinguish between enantiomers since: Absolute Configuration The absolute configuration of a molecule is the detailed stereochemical picture including how the atoms are arranged in space. Racemic Mixture (racemate) A mixture is said to be racemic when it contains exactly equal amounts of two enantiomers. Such a mixture is optically inactive (zero rotation of plane polarized light). Racemic mixtures are very common. (The difficult part is to produce exclusively one enantiomer)