Amino-and Imino-alditols

3 Amino- and Imino-alditols - Reviews on the syntheses of azasugars (imi-noalditols) from non-carbohydrate sources on the syntheses of azasugars, sugar amidines and related structures as inhibitors of carbohydrate-processing enzymes on the syntheses of glycosidase inhibitors with reference to nag-statin and on the use of aldolases in the chemo-enzymatic syntheses of iminoalditols have appeared. 

1 Acyclic Derivatives - l,5-Diazido-l,5-dideoxy-D-pentitols are readily reduced to the corresponding l,5-amino-l,5-dideoxy derivatives. (See above for the preparation of the diazido compounds).  

The reductive amination of monosaccharides with 8-aminopyrene-l,3,6-trisul-fate in a variety of organic acids, which act as catalysts, has been studied by capillary electrophoresis with laser-induced fluorescence detection.  

The thiazole-alditol derivative 18 has been synthesized by an asymmetric dihydroxylation of a diene-substituted thiazole derivative.  

Condensation of D- and L-arabinose, D-ribose, D-xylose, D-galactose, D-glucose and D-mannose with 2-hydrazino-6-methyl-4-oxopyrimidine afforded intermediate sugar (6-methyl-4-oxo-2-pyrimidinyl)hydrazones. Treatment of the latter in one pot with bromine-acetic acid-sodium acetate then acetic anhydride (to effect a cyclization-acetylation reaction) gave, after purification and de-O-acetyla-tion, derivatives 19 (n = 3 or 4, stereochemistry as defined by the starting aldose).  

13 Amino- and Imino-alditols. - A review (253 refs.) on the preparation, antiviral activity and glycoprotein maturation of deoxynojirimycin and its derivatives has appeared.  

AT-Methyl- and -butyl-derivatives of deoxynojirimycin, l,4-dideoxy-l,4-imino-D-arabinitol and 2,S-dideoxy-2,5-imino-D-mannitol have been studied by NMR spectroscopy to provide data for determining a conformational basis for the inhibition of glycosidase and HIV-1 replication activity by these types of compounds.  

The 1-amido-l-deoxy-D-glucitol derivative 23 has been prepared and shown to exhibit liquid crystal properties.  

Full details on the preparation of urethane derivatives of 3,4-di-O-benzyl-l,2,5,6-tetradeoxy-l,2 5,6-diimino-L-iditol from D-mannitol as well as the 3,4-dideoxy-L- Areo compounds 24 (R = C02 Bu or COiBn), from a hex-3-enitol, have been reported. (See Vol. 28, p. 230, ref. 66 for an earlier report). In both cases l,6-diamino-l,6-dideoxy-2,5-anhydroalditols were minor by-products. V-Boc-L-/V/o-l,2 5,6-bis-aziridino derivatives have proved to be versatile intermediates for the preparation of imino-alditols. For example, treatment of the 3,4-di-O-benzyl compound with diethylaluminium cyanide affords a 1 2 mixture of pyrrolidine 25 piperidine 26, and with dilithium tetrabromonickelate (Li2NiBr4) gives bromo-derivative 27 from which displacement of bromide allows further functionalization.  

5R-Dihydroxymethyl-3/ ,4R-dihydroxypyrrolidine (2,5-dideoxy-2,5-imino-D-mannitol, DMDP) has been isolated from the fermentation broth of Strepto-myces sp. KSC-5791 along with minor amounts of deoxynojirimycin and deoxymannojirimycin. The DMDP was shown to be a potent inhibitor of trehalases from Corynebacterium sp. and the diamondback moth (Phytella 

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Amino- and Imino-alditols.-The reductive amination of aldehydo-sugars with benzylamine in the presence of pyridinium borohydride in acetic acid-water-methanol has been reported to give good yields of Af-benzylaminoalditols without significant formation of dimeric products. ... 

Amino- and Imino-Alditols.- The synthesis of 1,2-diamino-dideoxy-D-g/yccro-L-manno- and D-g/ycero-L-g/uco-heptitol and their conversion into the same pyrazine (23) on reaction with benzil followed by acetylation and oxidation has been rqx>rted. ... 

O Amino and Imino-Alditols. A review on die chemical modifications of aza sugars including the nthesis of analogues of 1-deoxynojirimycin and its monno-isomer, as well as one on the aldolase-catalysed aldol condensations in die ndiesis of aza sugars, has tqipeared. ... 

The Sharpless asymmetric aminohydroxylation [552] of the electron-deficient 2-vinylfuran 469 gives a 7 1 mixture of semi-protected amino-alcohols 470 and 471 (41%). The major product 472 (ee > 86%) was reduced by diisobutylaluminum hydride giving a diol [553] which is then converted into the /3-hydroxyfurylamine derivative 473, an important synthetic building block for various biologically important compounds, including l,5-dideoxy-l,5-imino-alditols such as 474 (O Scheme 110). A less regioselective, but shorter way to intermediate 473 is the direct asymmetric aminohydroxylation of vinylfuran [554,555]. 

Syntheses of polyoxamic acid from pyroglutamic acid and L-tartaric acid and of a 4-amino-2,3-dihydroxyhexanedioic acid from pyroglutamic acid are covered in Chapter 16. Synthesis of imino-alditols are covered in Chapter 18. 

Several imino-alditols have been prepared from non-carbohydrate sources. 2,S-Dideoxy-2,S-imino-D-mannitol has been synthesized from a pyroglutamic acid derivative (see Vol. 27, p. 209, ref. 59 for the use of pyroglutamic acid in the synthesis of other imino-alditols), and 1-deoxy-L-allonojirimycin has been made from a protected L-serine derivative. A protected D-serine aldehyde provided access to a l,2,4-trideoxy-l,4-imino-D-eryrAro-pentitol derivative for incorporation into DNA, and reduction of the minor natural amino acid, 4-L-hydroxyproline, gave l,3,4-trideoxy-l,4-imino-D-eryrAro-pentitol which, after Af-acylation with a fluorescent probe, was incorporated into oligonucleotides. ... 

Cyclic imino derivatives of amino-alditols.- Several laboratories have reported studies on these compounds, which can show glycosid-ase inhibitory activity. Fleet s group has studied the plant alkaloids (22)-(24) which are analogues of glucose, fructose, and mannose respectively analysis of the inhibitory activity of these compounds towards a variety of glycosidases has shown that the... 

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