Editorial [Hot Topic: Bioorganic Chemistry (Guest Editor: Harri Lonnberg) ]

The current issue is Part I of the first thematic issue of Current Organic Chemistry devoted to Bioorganic Chemistry, a field the importance of which is nowadays self-evident. It consists of four extensive review articles dealing with the chemistry and enzymology of steroids, nucleosides and oligonucleotides. I believe that these articles are of considerable general interest and that they at the same time constitute a compilation of literature useful both for specialists working on related subjects and for newcomers entering these particular fields. Prof Mikhailopulo presents a survey of chemo-enzymatic methods applicable to preparation of structurally modified nucleosides of biological importance. Approaches utilizing whole cells, purified enzymes from wild-type bacteria and recombinant enzymes are covered. Increasing use of structurally modified oligonucleotides as tools for cell biology research and drug discovery creates increasing demand for large scale synthesis of modified nucleosides. Enzymatic methods in many cases offer at least a partial answer to this challenge. The contribution of Prof Mikhailov and coworkers gives an overview of the chemistry of disaccharide nucleosides. These interesting molecules are naturally occurring, being found as constituents of tRNA, antibiotics and other physiologically active compounds. Their structural chemistry, synthesis of and incorporation into oligonucleotides are discussed. The third review, contributed by Prof Lesnikowski, summarizes the techniques available for introduction of metal ion binding centers into oligonucleostides and gives illustrative examples of the versatile applications of such conjugates, including their utilization as electrochemical sensors, luminescent probes, artificial nucleases and constituents of nano-scale devices. The last article, from the group of Prof Wähälä, reviews the recent achievements in synthesis of estrone and estradiol steroids. Main attention is paid to reactions allowing attachment of a carbon chain directly to the carbon skeleton of the parent steroid ring system and to conversion of non-estranoid precursors to substituted estrone or estradiol derivatives. Finally, I thank all the authors for their thorough work, the results of which will undoubtedly benefit many orgaric chemists.