PubMed:34450528 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PubMed/sourceid/34450528","sourcedb":"PubMed","sourceid":"34450528","source_url":"https://www.ncbi.nlm.nih.gov/pubmed/34450528","text":"2,3-Carbamate mannosamine glycosyl donors in glycosylation reactions of diacetone-d-glucose. An experimental and theoretical study.\nThe role of the cyclic 2,3-N,O-carbamate protecting group in directing the selectivity of mannosylation reactions of diacetone-d-glucose, promoted by BSP/Tf2O via α-triflate intermediates, has been investigated through a combined computational and experimental approach. DFT calculations were used to locate the transition states leading to the α or β anomers. These data indicate the preferential formation of the β-adduct with mannosyl donors either equipped with the 4,6-O-benzylidene protection or without it. The synthetic results confirmed this preference, showing in both cases an α/β selectivity of 4:6. This highlights a role for the 2,3-N,O-carbamate in sharp contrast with what described in the case of 2,3-O-carbonate mannosyl donors.","tracks":[{"project":"GlyCosmos6-Glycan-Motif-Structure","denotations":[{"id":"T1","span":{"begin":84,"end":91},"obj":"https://glytoucan.org/Structures/Glycans/G15021LG"},{"id":"T2","span":{"begin":261,"end":268},"obj":"https://glytoucan.org/Structures/Glycans/G15021LG"}],"attributes":[{"subj":"T1","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Structure"},{"subj":"T2","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Structure"}]},{"project":"GlyCosmos6-Glycan-Motif-Image","denotations":[{"id":"T1","span":{"begin":84,"end":91},"obj":"Glycan_Motif"},{"id":"T2","span":{"begin":261,"end":268},"obj":"Glycan_Motif"}],"attributes":[{"id":"A1","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G15021LG"},{"id":"A2","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G15021LG"},{"subj":"T1","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Image"},{"subj":"T2","pred":"source","obj":"GlyCosmos6-Glycan-Motif-Image"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"GlyCosmos6-Glycan-Motif-Structure","color":"#ece893","default":true},{"id":"GlyCosmos6-Glycan-Motif-Image","color":"#ce93ec"}]}]}}