Chemo-enzymatic approaches

Two appendices are included at the end of this chapter. The first is intended to serve as a reminder, for those of you who might need it, of the nomendature and representation of stereoisomers. The second appendix contains descriptions of various chemo-enzymatic methods of amino acid production. This appendix has been constructed largely from the recent primary literature and includes many new advances in the field. It is not necessary for you to consult the appendix to satisfy the learning objectives of the chapter, rather the information is provided to illustrate the extensive range of methodology assodated with chemo-enzymatic approaches to amino add production. It is therefore available for those of you who may wish to extend your knowledge in this area. Where available, data derived from die literature are used to illustrate methods and to discuss economic aspects of large-scale production. 

Chemical and Chemo-Enzymatic Approaches to Glycosidase Inhibitors with Basic Nitrogen in the Sugar Ring... 

The problem was solved using a more traditional chemo-enzymatic approach in which the sugar amino group was preliminarily protected by reacting 8 with... 

For instance, subtilisin-catalyzed esterification of lactosides has been used for a chemo-enzymatic approach to 6 -deoxy-6 -fluoro- and 6-deoxy-6-fluoro-lactosides... 

A more attractive chemo-enzymatic approach for the production of he-mithiocyclodextrins has been developed. More than ten years ago, cyclodextrin glucosyltransferase (CGTase) was shown to use a-maltosyl fluoride for the synthesis of a-, ft-, and y-cyclodextrins [47] and has been used for the chemoenzymatic synthesis of regioselectively substituted cyclodextrins [48]. For this purpose, 4-thio-a-maltosyl fluoride (58) was easily prepared from (45). Incubation of (58) in the presence of pure CGTases afforded hemithiocyclodex-trins (57a), (57b) and (57c) isolated in 14,16 and 15% yields respectively [49]. 

Lu W, Chen P et al (2008) New stereoselective synthesis of thiamphenicol and florfenicol from enantiomerically pure cyanohydrin a chemo-enzymatic approach. Tetrahedron 64 7822-7827... 

Enzymatic and Chemo-Enzymatic Approaches Towards Natural and Non-Natural Alkaloids Indoles, Isoquinolines, and Others... 

A significant number of tryptophan and tryptamine chemical syntheses are known this section describes their biological synthesis in vivo (whole cells), the in vitro enzymatically catalysed synthesis and synthesis through chemo-enzymatic approaches. 

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