Chemical Evolution of Biopolymers

The solid phase synthesis of oligonucleotides has not reached the level of sophistication as that for peptides. The design of an appropriate solid support has been difficult with such problems as undesirable polymer characteristics and irreversible adsorption of reagents onto the support. Only recently have appropriate polymer matrices (e.g., HPLC silica) been described that appear to have potential for the synthesis of nucleotide polymers. In fact, a major impetus for the development of solid phase methodology for the synthesis of polydeoxyribonucleotide (DNA) sequences has been the industrial application of the so-called biotechnology or recombinant DNA technology. 

Hydrogen cyanide and formaldehyde are in turn precursors of more reactive compounds such as aminoacetonitrile and aminoacetamide. A combination of these molecules can lead to the formation of amino acids, purines, pyrimidines, and sugars. For example  

This transformation is reminiscent of the well-known Strecker amino acid synthesis  

The hydrolysis of the nitrile yields the corresponding amino acid. 

Oro in 1960 first demonstrated the synthesis of a nucleic acid component (43,44). By refluxing a concentrated solution of ammonium cyanide he obtained adenine in low yield. Later it was found that UV irradiation of a dilute HCN solution produced adenine and guanine. 4-Amino-5-cyano-imidazole and 4-aminoimidazole-5-carboxamide have been shown to be important intermediates in these reactions. Furthermore, NH3 and HCN could be converted to formamidine (H2NCH=NH). 

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Many characteristics of hyaluronan are wonderful inventions of evolution. Such an evolutional definition could obviously be attributed to other biopolymers such as proteins, nucleic acids and polysaccharides. Indeed, evolutional potential, mostly related to biopolymers, strongly depends on molecular physico-chemical nature [1]. HA is considered one of the earliest evolutional forms of the polysaccharide family. So, let s look at hyaluronan s biological role in comparison with the molecular evolutions of other biopolymers. 

To summarize, there exist three chemical evolution models that parallel synthetic polymerization procedures and whose reaction conditions may be used as strategies forbiomimetic syntheses of biopolymers from organic synthons ... 

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