PubMed:2171766 JSONTXT

{"project":"sentences","denotations":[{"id":"TextSentencer_T1","span":{"begin":0,"end":310},"obj":"Sentence"},{"id":"TextSentencer_T2","span":{"begin":311,"end":446},"obj":"Sentence"},{"id":"TextSentencer_T3","span":{"begin":447,"end":586},"obj":"Sentence"},{"id":"TextSentencer_T4","span":{"begin":587,"end":676},"obj":"Sentence"},{"id":"TextSentencer_T5","span":{"begin":677,"end":779},"obj":"Sentence"},{"id":"TextSentencer_T6","span":{"begin":780,"end":953},"obj":"Sentence"},{"id":"TextSentencer_T7","span":{"begin":954,"end":1063},"obj":"Sentence"},{"id":"T1","span":{"begin":0,"end":310},"obj":"Sentence"},{"id":"T2","span":{"begin":311,"end":446},"obj":"Sentence"},{"id":"T3","span":{"begin":447,"end":586},"obj":"Sentence"},{"id":"T4","span":{"begin":587,"end":676},"obj":"Sentence"},{"id":"T5","span":{"begin":677,"end":779},"obj":"Sentence"},{"id":"T6","span":{"begin":780,"end":953},"obj":"Sentence"},{"id":"T7","span":{"begin":954,"end":1063},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Use of the methylsulfenyl cation as an activator for glycosylation reactions with alkyl (aryl) 1-thioglycopyranosides: synthesis of methyl O-(2-acetamido-2- deoxy-beta-D-glucopyranosyl)-(1----6)-O-alpha-D-glucopyranosyl-(1----2) -alpha-D -glucopyranoside, a derivative of the core trisaccharide of E. coli K12.\nMethylsulfenyl bromide (MSB) and methylsulfenyl trifluoromethanesulfonate (MST) have been used to prepare 1,2-cis-linked disaccharides. Ethyl (phenyl) 1-thio-beta-D-gluco- and galacto-pyranosides having non-participating (benzyloxy) protecting groups were used as the donors. The alpha beta-ratio of the products depended on the promoter and conditions of reaction. Intimate ion-pairs, formed initially, may be responsible for the steric outcome of the glycosylations. Thus, with ethyl 2,3,4,6-tetra-O-benzyl-alpha-D-mannopyranoside as a donor, moderate quantities of the beta-linked disaccharide could be produced using MSB as the activator. The synthesis of the title trisaccharide glycoside that contains 1,2-cis and 1,2-trans-linkages is described."}

{"project":"mondo_disease","denotations":[{"id":"T1","span":{"begin":386,"end":389},"obj":"Disease"}],"attributes":[{"id":"A1","pred":"mondo_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/MONDO_0008040"}],"text":"Use of the methylsulfenyl cation as an activator for glycosylation reactions with alkyl (aryl) 1-thioglycopyranosides: synthesis of methyl O-(2-acetamido-2- deoxy-beta-D-glucopyranosyl)-(1----6)-O-alpha-D-glucopyranosyl-(1----2) -alpha-D -glucopyranoside, a derivative of the core trisaccharide of E. coli K12.\nMethylsulfenyl bromide (MSB) and methylsulfenyl trifluoromethanesulfonate (MST) have been used to prepare 1,2-cis-linked disaccharides. Ethyl (phenyl) 1-thio-beta-D-gluco- and galacto-pyranosides having non-participating (benzyloxy) protecting groups were used as the donors. The alpha beta-ratio of the products depended on the promoter and conditions of reaction. Intimate ion-pairs, formed initially, may be responsible for the steric outcome of the glycosylations. Thus, with ethyl 2,3,4,6-tetra-O-benzyl-alpha-D-mannopyranoside as a donor, moderate quantities of the beta-linked disaccharide could be produced using MSB as the activator. The synthesis of the title trisaccharide glycoside that contains 1,2-cis and 1,2-trans-linkages is described."}

{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":298,"end":305},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":805,"end":812},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"562"},{"id":"A2","pred":"db_id","subj":"T2","obj":"100829"}],"text":"Use of the methylsulfenyl cation as an activator for glycosylation reactions with alkyl (aryl) 1-thioglycopyranosides: synthesis of methyl O-(2-acetamido-2- deoxy-beta-D-glucopyranosyl)-(1----6)-O-alpha-D-glucopyranosyl-(1----2) -alpha-D -glucopyranoside, a derivative of the core trisaccharide of E. coli K12.\nMethylsulfenyl bromide (MSB) and methylsulfenyl trifluoromethanesulfonate (MST) have been used to prepare 1,2-cis-linked disaccharides. Ethyl (phenyl) 1-thio-beta-D-gluco- and galacto-pyranosides having non-participating (benzyloxy) protecting groups were used as the donors. The alpha beta-ratio of the products depended on the promoter and conditions of reaction. Intimate ion-pairs, formed initially, may be responsible for the steric outcome of the glycosylations. Thus, with ethyl 2,3,4,6-tetra-O-benzyl-alpha-D-mannopyranoside as a donor, moderate quantities of the beta-linked disaccharide could be produced using MSB as the activator. The synthesis of the title trisaccharide glycoside that contains 1,2-cis and 1,2-trans-linkages is described."}