Pseudo-trisaccharides

The pseudo trisaccharide 67 has been prepared by coupling of l,3,4,5-tetra-0-... 

In the synthesis of a Sialyl Lewis X analogue, l,4,5,6-tetradeoxy-l,4-imino-D-ido-hexitol (for synthesis see Section 1.3.1) was a-L-fucosylated at the less hin> dered (C-2) hydroxyl, then p-D-galactosylated at 0-3 to produce a non-sulfated precursor to the pseudo-trisaccharide 137. ... 

A synthesis of 6-deoxy-6-hydroxyamino- -D-glucopyranoside from the corresponding 6-aminosugar by the sequence of oxidation with hydrogen peroxide - sodium tungstate to the oxime followed by cyanoborohydride reduction was copied in a synthesis of the pseudo-trisaccharides 6 -N-hydroxykanamycin A and 6 -N-hydroxydibekacin from the corresponding parent antibiotics, but the products were... 

The same group has also reported an analogous synthesis of the pseudo-trisaccharide adiposin-1 (43). ... 

Interesting syntheses have been reported of Escherichia coli lipid A (218), of the pseudo-trisaccharide destomycin C (219), which as well as a cyclitol fragment contains an unusual spiro-orthoester interglycosidic linkage, and of the anthracyclinone sugars daunosamine (220) and acosamine (221). ... 

Reviews have appeared on the synthesis of aminoglycoside antibiotics, and on the formation of new aminocyclitol antibiotics by mutants of amino-cyclitol-producing organisms fed with aminocyclohexanol or related subunits. The structures of eight minor components of the nebramycin complex elaborated by Streptomyces tenebrarius have been elucidated besides neamine and related pseudo-disaccharides, the new components are pseudo-trisaccharides related to kanamycin B, and the 3 -hydroxy analogue of the principal component of the complex, apramycin (see Vol. 10, p. 130). ... 

A complex of copper ions was used for the chemoselective preparation of the 6, 3-di-NHBoc derivative of kanamycin A (29) from the parent AG (6) in 72% yield (Scheme 6.3b) [43]. Another example for selective amine-protecting group manipulations on the scaffold of the pseudo-trisaccharide scaffold of the AG sisomicin (13) is demonstrated in Scheme 6.3c. Three amine groups of sisomicin (13) were selectively protected using the NH-trifluoroacetamide and NH-Boc groups. The 6 -aminomethylene of the free base form of 13 was selectively... 

The syntheses of the pseudo-pentasaccharide derivative of neomycin B (Compound 99, Scheme 6.14a) and of the pseudo-trisaccharide AG analog 107 (Scheme 6.14b) were chosen as examples of common and useful synthetic manipulations that are performed on AG scaffolds. The detailed synthetic procedures for the preparation and purification of these AG derivatives are described in this section. 

Scheme 6.14 Syntheses of the pseudo-pentasaccharide derivative of neomycin B (99) and of the pseudo-trisaccharide AG analog (107).

C-N,m.r. data have been given for the pseudo-trisaccharide antibiotic LL-BM 123 (see Vol. 11 p.l54), which contains myo-inosamine-2, and the pseudo-disaccharide LL-BM 782 (see Vol. 15, p.l82), containing myo-inositol. The n.m.r. data support a... 

Novel insect chitinase inhibitors, allosamidin (1) and methyl allosamidin (2), have been characterized as pseudo-trisaccharides... 

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