Guanine tetrameric

A series of Zn(n) and Cd(n) complexes of adenine and guanine derivatives has been characterized by single-crystal X-ray analysis and NMR spectroscopy ( H, ROESY, and Cd). A wide range of stractural types, including monomeric, dimeric, tetrameric, and polymeric architectures incorporating the N-7 atoms of the nucleobases, has been obtained. Additional metal-nucleobase coordination has generally been observed at the N -site of the adenine derivatives. 

The structure of the most celebrated supramolecular structure was published more than 50 years ago, in the April 2, 1953, issue of Nature, when Watson and Crick proposed "a structure for Deoxyribose Nucleic Acid," the current paradigm for the structure of life. While the ability of the guanine moiety to form tetrameric. planar... 

Fig. 5 (a) Tetrameric arrangement of guanine bases for the Guo-3 -P gel and (b) the continuous helical arrangement in the Guo-5 -P gel. Reprinted with permission from J Biomol Struct Dyn 1990, 8, 491... 

Figure 8 Coordination driven assembly to discrete structures (a) Fujita group s assembly with four tridentate ligands and six palladium atoms forms a tetrameric cage (b) Guanine derivatives assemble into planar tetramers that can use a metal coordinate to stack into more complex structures. ...

Related processes are the formation of discotic mesogens from hydrogen-bonded phenan-thridinone derivatives [14a] and especially of helical mesophases based on tetrameric cyclic arrangements (G-quartets) of guanine-related molecules [14b]. 

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