On stacking

Abstract

The term 'stacking' is normally associated with Π- Π interactions between aromatic moieties. The parallel alignment between adjacent DNA bases arguably constitutes the best-known example and provides the dominating contribution to the overall stability of DNA duplexes. Beyond canonical Π- Π interactions, a preliminary inspection of crystal structures of nucleic acids and their complexes with proteins reveals a wealth of additional stacking motifs including edge-to-face, H-Π , cation-Π , lone pair-Π and anion-Π interactions. Given the ubiquity and diversity of such motifs it seems reasonable to widen the meaning of stacking beyond the standard cofacial interactions between pairs of aromatics. © Springer Science+Business Media B.V. 2010.