Tetramethylguanidinium azide as a new reagent for the stereoselective synthesis of glycosyl azides

Li, C.; Arasappan, Ashok; Fuchs, P. L.

doi:10.1016/s0040-4039(00)73629-x

Cited by 32 publications

(5 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Completion of the synthesis of α-azidoketone 5 simply involved treatment of ketone 91 α with phenyltrimethylammonium perbromide (PTAB) in THF for short reaction times to afford α-bromoketone 95 (80%, 94% based on recovered 91 α) which was subjected to reaction with tetramethylguanidinium azide (TMGA) in nitromethane (Scheme ). This protocol smoothly generated α-azidoketone 5 in 75−85% yield (nearly quantitative on small scales).…”

Section: Stereoselective Reduction Of Hindered Bromidesmentioning

confidence: 99%

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate¹

et al. 1999

View full text Add to dashboard Cite

Hecogenin acetate (1) was converted to North 1 azidoketone 5 involving several key transformations: (1) conversion of cyclic sulfate 33b to allylic alcohol 40 via Reich iodoso olefination; (2) E-ring annulation via intermolecular oxygen alkylation of highly functionalized secondary alcohol 40 using rhodium-catalyzed decomposition of an α-diazophosphonoacetate to provide α-alkoxyphosphonoacetate 52, with subsequent intramolecular Wadsworth−Emmons reaction to provide alkoxydihydrofuran 53; and (3) establishment of the C20 stereochemistry by chromium(II) reduction of tertiary bromide 86 to a 9:1 mixture of diastereomeric spiroketals 90α/90β, separated as silyl ethers 91α/91β. Conversion of 91α to α-azidoketone 5 was uneventful.

show abstract

Section: Stereoselective Reduction Of Hindered Bromidesmentioning

confidence: 99%

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate¹

et al. 1999

View full text Add to dashboard Cite

show abstract

“…More typically, the crude iodide donors were directly reacted with tetrabutylammonium azide (TBAN 3 ) or tetramethylguanidinum azide (TMGA) 8 in CH 2 Cl 2 to afford the per-O-acetyl glycosyl azides. The results from the above experiments appear in Table 1.…”

Section: Resultsmentioning

confidence: 99%

General methods for the synthesis of glycopyranosyluronic acid azides

Ying

Gervay‐Hague

2003

Carbohydrate Research

View full text Add to dashboard Cite

Per-O-acetylated D-glycopyranoses derived from both mono-and disaccharides were first converted to glycosyl iodides and subsequently reacted with an azide source to achieve the stereoselective synthesis of b-D-glycosyl azides after deacetylation. Low-temperature (4°C) TEMPO oxidation of the monosaccharides provided the corresponding uronic acids, which were purified as the free acids. Oxidation of the lactosyl-and cellobiosyl azides resulted in diacid formation. However, 4%,6%-O-benzylidene protection enabled selective oxidation of the C-6 hydroxyl. 2-Acetamido-2-deoxy-D-glycopyranosyl azides were also prepared and converted to uronic acids completing the library synthesis.

show abstract

“…The solutions were diluted with toluene, evaporated to dryness and purified by flash column chromatography on silica gel using 20% ethyl acetate in toluene as an eluent. The 2,3,4,6-tetra- O -benzoyl-β- d -glucopyranosyl azide ( 12 ), 36,37 2,3,4,6-tetra- O -benzoyl-β- d -galactopyranosyl azide ( 13 ), 38 and 2,3,4,6-tetra- O -benzoyl-β- d -mannopyranosyl azide ( 14 ) 37 are reported.…”

Section: Methodsmentioning

confidence: 99%

Synthesis of β-Glycosyl Amides from N-Glycosyl Dinitrobenzenesulfonamides

Gaitonde

Sucheck

2012

Journal of Carbohydrate Chemistry

View full text Add to dashboard Cite

The N-glycosyl-2,4-dinitrobenzenesulfonamides were accessed via benzoyl-protected β-glycosyl azides. The azides were reduced with Adams’ catalyst to the corresponding amines. The glycosylamines were sulfonated with 2,4-dinitrobenzenesulfonyl chloride to form N-glycosyl-2,4-dinitrobenzenesulfonamides in moderate yields. β-Glycosyl amides were then prepared in 67 – 81 % yields by treatment of the sulfonamides with thioacetic acid and cesium carbonate. The conversion of the glycosylsulfonamide to the glycosyl amide proceeded with high stereoselectivity.

show abstract

Tetramethylguanidinium azide as a new reagent for the stereoselective synthesis of glycosyl azides

Cited by 32 publications

References 30 publications

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate¹

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate¹

General methods for the synthesis of glycopyranosyluronic acid azides

Synthesis of β-Glycosyl Amides from N-Glycosyl Dinitrobenzenesulfonamides

Contact Info

Product

Resources

About

Tetramethylguanidinium azide as a new reagent for the stereoselective synthesis of glycosyl azides

Cited by 32 publications

References 30 publications

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate1

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate1

General methods for the synthesis of glycopyranosyluronic acid azides

Synthesis of β-Glycosyl Amides from N-Glycosyl Dinitrobenzenesulfonamides

Contact Info

Product

Resources

About

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate¹

Synthesis of the North 1 Unit of the Cephalostatin Family from Hecogenin Acetate¹