Amino-sugar Nucleosides

The Hilbert-Johnson reaction of a protected 2-amino-2-deoxy-D-glucopyranosyl chloride (14) has been used in the synthesis of amino sugar nucleosides.13... 

Benzylsulfonyl as N-Blocking Group in Amino Sugar Nucleoside Synthesis, M. L. Wolfrom and R. Wurmb,/. Org. Chem., 30, 3058-3061 (1965). 

Treatment of 5-deoxy-5-halogeno nucleosides of adenine and uracil with trimethylamine yielded the corresponding 5-deoxy-5-trimethylammonium salts, whose interaction with anionic polynucleotides was then examined. Various A -alkyl, A -cycloalkyl, and iV-alkaryl derivatives of 3-amino-3-deoxy-and 3, 5 -diamino-3, 5 -dideoxy-adenosine have been prepared from the amino-sugar nucleosides the 3 -benzylamino derivative gave the unusual oxazolidine derivative (52). ° ... 

Halogeno-sugar and Amino-sugar Nucleosides Thionucleosides... 

References to branched-chain amino-sugars and to amino-sugar nucleosides can be found in Chapters 19 and 20 respectively. 

The synthesis and biological response properties of new amino-sugar nucleosides have been reviewed. ... 

Several papers describe the synthesis of azido-sugar precursors to amino-sugar nucleosides. The unsaturated nucleosides (34) were converted to the corresponding amino-compounds (35) by sequential treatment with triphenyl-phosphine-tetrabromomethane and lithium azide followed by reduction, the product amines then being coupled to amino-acids to give amino-acyl derivatives, which showed slight antitumour activity. " A facile new synthesis of 2 -amino-2 -... 

In the last two years the trifluoroaeetyl group was used as an amino-protecting group for the synthesis of steroid glycosides of amino sugars and amino sugar nucleosides . ... 

A marked increase in the number of papers indicates renewed interest in amino-sugar nucleosides. The 5 -aldehydo-nucleosides (415) were used as starting materials in syntheses of the amino-acid derivative (416) and the 5 -C-amino-methyl derivative (417) of adenosine. The first synthesis was accomplished by... 

Several azido- and amino-sugar nucleosides have been shown to exhibit antiviral and antitumour properties, which has triggered interest in their synthesis. In general, aminosugar nucleosides... 

Azido-5 -deoxy-nucleosides auid 5 -azido-2, 5 -dideoxy nucleosides have been prepared by a polymer support method, using polystyrenesulphonyl chloride reagent in conjunction with lithium azide,which on triphenylphosphine reduction yielded the corresponding amino-sugar nucleosides. ... 

Whereas low and medium polarity analytes are usually well suited for El, highly polar or even ionic compounds, e.g., diols or polyalcohols, amino acids, nucleosides, peptides, sugars, and organic salts should not be subject to El unless properly derivatized prior to EI-MS. [70-75]... 

Amino sugars are components of antibiotic substances109 and bacterial polysaccharides,1,0 and are therefore of interest. The nucleoside antibiotics amicetin, bamicetin, and plicacetin contain, as the sugar residue, a monoaminopentadeoxy disaccharide that is closely related to maltose. In view of the reported antibiotic and antitumor properties of these pyrimidine nucleosides,111,112 the synthesis of aminodeoxy derivatives of maltose would be of interest. 

Significant stability of ketohexose nucleosides in various media has facilitated their direct transformation, leading to important structures of biological interest, such as branched-chain and rare-sugar nucleosides (for example, amino-, epimino-, thio-, and trideoxy-nucleosides). 

In contrast to nucleophilic additions to ketoses, which very often lead to diastereoisomeric products, additions to ketonucleosides have been found to be highly stereoselective, permitting ready synthesis of amino-, epimino-, triazolo-, and other rare-sugar nucleosides. 

The nature and position of the carbon-nitrogen linkage in the 2-amino sugars endows them with unique properties and biological function that differ widely for example, from those of the nucleotide and nucleoside type of molecule. These substances are theoretically derived by condensation of an amine with carbon atom 1 of a hexose. Although no biogenetic relationship between these two groups has yet been discovered such a possibility cannot be discounted. 

Formamide is itself hydrolyzed by water, meaning that it persists only in a relatively dry environment, such as a desert. Desert environments recently proposed as being potential sites for the prebiotic synthesis of ribose18 may hold formamide as well. Since formamide boils at —400 K, a mixture of formamide and water, if placed in the desert, would lose its water over time and end up as a pool of formamide. Within this pool, many syntheses are thermodynamically favorable polypeptides from amino acids, nucleosides from sugars and bases, nucleotides from nucleosides and inorganic phosphate, and RNA from nucleotides. Indeed, phosphate esters are also spontaneously synthesized. This includes ATP (from ADP and inorganic phosphate), nucleosides (from ribose borates and nucleobases), peptides (from amino acids), and others.19-21... 

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