The structural complexity of biomolecules

The present review has been written with the aim of presenting the various aspects of molecular geometry relevant to stereoisomerism, namely symmetry, configurational and conformational isomerism, enantiomerism and diastereoisomerism. It certainly was apparent to the reader that the examples were never examined for the full spectrum of their stereochemical features, but only for that particular aspect under 

As opposed to fundamental stereochemists, biochemists cannot choose or design the molecules they plan to investigate from a stereochemical viewpoint. These molecules tend to be characterized by their structural complexity, among other aspects a large number of degrees of conformational freedom, and several elements of stereoisomerism. 

One of the aspects of structural complexity in biomolecules is that of stereochemistry. To the increase in stereochemical complexity when going to larger biomolecules correspond new stereochemical features and properties. Thus, the concepts of cycloenantiomerism, cyclodiastereoisomerism and cyclostereoisomerism have been introduced by Prelog and collaborators [118-120] to describe stereochemical features of cyclic molecules displaying 2n centers of chirality, e.g., cyclic polypeptides. 

1 Schoffeniels, E. (1976) Anti-Chance (translated from the French by B.L. Reid), Pergamon, Oxford, pp. 80-85. 

2 Testa, B. (1979) Principles of Organic Stereochemistry, Dekker, New York. 

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