Synthesis of inositol glycan cyclic phosphates

Abstract

An efficient synthesis of tri-, tetra-, and pentasaccharide cyclic phosphates 1-5, structurally related to natural inositol phosphate glycans, is reported. The title compounds were assembled by PhSeOTf-promoted glycosylation of the known glucosamine precursor, t-butyldimethylsilyl 2-azido-3,6-di-O-benzyl-2-deoxy-b-D-glucopyranoside (8) with protected 1-methylthio mono-, di-, and trimannosides 7a-c, and, after conversion into glycosyl fluorides, Cp 2 ZrCl 2 -AgOTf-promoted glycosylation of differentially protected optically pure 1D-myo-inositol 11. The syntheses were completed by installing the cyclic phosphate moieties with methylpyridinium dichlorophosphate and finally, removal of all protecting groups by dissolving-metal reduction.

Synthesis and antimicrobial evaluation of carbohydrate and polyhydroxylated non-carbohydrate fatty acid ester and ether derivatives

“…The solution was washed with 21 water, dried over anhydrous MgSO 4 , and concentrated under diminished pressure. 24 …”

“…14 MeOH (10 mL) was added to quench the solution which was stirred for a further 1 15 hr. 24 The mixture was then concentrated under diminished pressure and purified by 16 chromatography (petroleum ether-EtOAc) to give 10a. Compound 10a (1.7 g, 3.6 mmol) was dissolved in MeOH (50 mL) and a catalytic 6 amount of TsOH was added.…”

Stereoselective enzymatic synthesis of monoglucosyl-myo-inositols with in vivo anti-inflammatory activity

“…Consequently, the synthesis of partially protected inositols with free hydroxyl groups at specific positions has been the subject of intensive research. [14][15][16][17][18][19][20] However, due to the similar reactivity of the multiple inositol hydroxyl groups, the controlled glycosylation remains a challenge in organic chemistry. 2 In this context, considering that one of the most interesting properties of enzymes is their regio-and stereoselectivity, a biocatalytic approach represents an interesting alternative to cope with this limitation.…”

Synthesis and biological evaluation of prodrugs of 2-fluoro-2-deoxyribose-1-phosphate and 2,2-difluoro-2-deoxyribose-1-phosphate

“…21 We also investigated the P(III) strategy: we tried to use the phosphoramidite, 22 phosphoradiamidite 23 and H-phosphonate 24 methodologies. We decided to try the phosphorylation with charged phosphorylating agents such as methyl pyridinium dichlorophosphate 25 or of the dibarium salt of 2-cyanoethylphosphate 26 in order to stabilize the resulting phosphate. To finish our study, we decided to invert our strategy by placing the leaving group on the anomeric position of the sugar 15a,b, 27 and to use the phosphate reagent as the attacking agent.…”