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| Importance of Steoreochemistry |
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| Stereochemistry, an important aspect of carbon compounds, is a feature that is widely prevalent in nature. The human body is structurally chiral with the heart lying to the left and the liver to the right. Many climbing plants show chirality in the way that they wind around supporting structures. Most of the molecules found in plants and animals are chiral and usually only one form of chiral molecules occurs in a species. |
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| Stereochemistry concerns the nature of molecular shape and therefore has direct impact on the physical and chemical properties of compounds. |
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| In pharmaceutical products only one enantiomer is the effective therapeutic agent, while the second enantiomer has no activity, or functions in a very different manner. In most cases, only one enantiomer is found to have the desired effect while the other isomer may be totally inactive or has an opposite effect. For example, it is the (S)-enantiomer of ibuprofen that has the pain relieving action. (-) -thyroxine, an amino acid of thyroid gland speeds up metabolic processes and causes nervousness and loss of weight. Its enantiomer, (+) - thyroxine, has none of this effect but is used to lower the cholesterol levels. |
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| In foods, the chirality of compounds determines the nutritional value, sensory properties or biological activity. |
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 Enantiomers of a chemical may have very different flavors. |
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Detection of an unnatural ratio of enantiomers can provide evidence of adulteration of a food product or exposure to harsh processing conditions. |
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All naturally occurring sugars including the sugars that occur in DNA are of D-configuration. The enzyme, yeast can specially ferment D-glucose and not its L-enantiomer. |
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All but one of the twenty naturally occurring amino acids that make up proteins have L-configuration. The synthesized D-proteins made form D-amino acids are somewhat resistant to breakdown by protein digesting enzymes because they do not have the chirality to fit in the active sites of these enzymes. |
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| Stereochemistry also plays an important role in deciding the physiological properties of compounds. (-) - Nicotine is much more toxic than (+) - Nicotine, (+) - adrenaline is very active in constriction of blood vessesl than (-) - adrenaline. |
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| Stereochemistry is also used to determine reaction rates. |
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