9-amino-, 9-deoxy-, synthesis

Glyphosate also inhibits the activity of a form of 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (13), however, this inhibition is relatively weak. Effects of glyphosate on the enzymes of aromatic amino acid synthesis have been described in more detail in recent reviews (14-17). 

Inverse type hetero-Diels-Alder reactions between p-acyloxy-a-phenylthio substituted a, p-unsaturated cabonyl compounds as 1-oxa-1,3-dienes, enol ethers, a-alkoxy acrylates, and styrenes, respectively, as hetero-dienophiles result in an efficient one step synthesis of highly functionalized 3,4-dihydro-2H-pyrans (hex-4-enopyranosides). These compounds are diastereospecifically transformed into deoxy and amino-deoxy sugars such as the antibiotic ramulosin, in pyridines having a variety of electron donating substituents, in the important 3-deoxy-2-gly-culosonates, in precursors for macrolide synthesis, and in C.-aryl-glucopyranosides. 

R. Kuhn, D. Weiser, and H. Fisher, Amino-sugar synthesis. XXIII. 3-Amino-3-deoxy-D-xy/o-hexose and 3-amino-3-deoxy-D-uru()ino-hexose, Ann., 641 (1959) 132-137. 

The amino nitrile synthesis is particularly useful for the preparation of 2-amino-2-deoxy derivatives of rare sugars which would be difficult to obtain as intermediates in a synthesis involving animation alone. Thus, 2-amino-2-deoxy-L-glucose and 2-amino-2-deoxy-L-mannose can be prepared in good yield from the readily available L-arabinose.11,18... 

Amino-%-deoxy derivative of Mode of synthesis Melting point, °C. Hydrochloride ... 

Basic studies concerning their total synthesis have been undertaken by S. Umeza-wa and co-workers All the 0-(amino-deoxy-a-D-glucopyranosyl)-2-deoxystrept-amines listed in Table 2 have been synthesized by a modified Koenigs-Knorr condensation or via the nitrosyl chloride method mentioned above. 

The furoisoxazoline (8) has been used for the total synthesis of amino-deoxy pentose and pentitol derivatives, synthesis of the latter being outlined in Scheme 5. ... 

Mention of acetyl migration in the synthesis of amino-deoxy-... 

The well-known cytoplasmic shikimate pathway is important to aromatic amino acid synthesis. It takes a long metabolic pathway to reach to an aromatic amino acid from D-glucose. Two metabolic intermediates, phosphoenolpymvate from the glycolytic pathway and D-erythrose-4-phosphate from the pentose-phosphate pathway, must combine to form 3-deoxy-7-phospho-D-arabinoheptulosonate before formation of 3-dehydroquinate (Fig. 13.4). Thus, there are still several barriers difficult to overcome in the already existing technologies of shikimate fermentation from D-glucose (Draths et al. 1999). 

An alternative approach to the use of a-aminoketones involves acetals (72JOC221) and pyrazine-2,3-diones have been synthesized by this route (Scheme 58). The acetals are readily available from the phthalimido derivatives via the a-chloroketones. Hemiacetals have also served as a starting point for pyrazine synthesis, although in most cases hemiacetals are too labile to be easily prepared examples are common in the 2-amino-2-deoxy sugar series 2-amino-2-deoxy-D-glucose for example dimerizes to the pyrazine (101) when generated in situ from the hydrochloride salt (68JAP6813469). 

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