Describe the term D- and L- configuration used for amino acids wi… - Vidyadip

Question

Describe the term $D-$ and $L-$ configuration used for amino acids with examples.

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Answer

The sugars are divided into two families: the $D-$family and $L-$family which have definite configurations. These configurations are represented with respect to glyceraldehyde as the standard. The glyceraldehydes may be presented by two forms as:
$D-(+)-$Glyceraldehyde $L-(-)-$Glyceraldehyde The $D-$configuration has $-OH$ attached to the carbon adjacent to $-CH_2OH$ on right while $L-$configuration has $-OH$ attached to the carbon adjacent to $-CH_2OH$ on left. The sugars are called $D-$ or $L-$depending upon whether the configuration of the molecule is related to $D-$glyceraldehyde or $L-$glyceraldehyde. It has been found that all naturally occurring sugars belong to $D-$series, e.g., $D-$glucose $D-$ribose and $D-$fructose.

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