Deoxy-azasugars

A variety of amino-alcohol derivatives have been used as substrates for RCM approaches to piperidines. Representative examples of these methods are shown in Scheme 18 (32, <01TL1209> 33, <01TA817> 34, <02OL4499). Application of this chemistry to the synthesis of deoxy-azasugars and hydroxypyrrolizidines has been reported <01TL4079>. 

Stereodivergent synthesis of 1-deoxy azasugars of the nojirimycin type by two-step enzymatic aldolization/catalytic reductive amination (a DHAP P ase H2/Pd-C). 

Dondoni, A, Merino, P, Perrone, D, Totally chemical synthesis of azasugars via thiazole intermediates. Stereodivergent routes to (—)-nojirimycin, (—)-mannojirimycin and their 3-deoxy derivatives from serine. Tetrahedron, 49, 2939-2956, 1993. 

Aldolases accept a wide range of aldehydes in place of their natural substrates and permit the synthesis of carbohydrates such as azasugars, deoxy sugars, deoxythio sugars, fluoro-sugars, and C8 or C9 sugars. In the case of D-fructose-1,6-diphosphate aldolase (FDP aldolase, Type A), more than 75 aldehydes have been identified as substrates [143]. 

The structural resemblance of azasugars (1-deoxy sugars in which an... 

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