title: Stereoselective Synthesis of Natural and Non-natural Thomsen-nouveau Antigens and Hydrazide Derivatives.
abstract: A selective glycosylation strategy enabling access to all stereochemical combinations of tumor associated Thomsen-nouveau (Tn) antigen, D-GalNAc-O-Ser/Thr, has been developed. The key component for selectivity is the phthalimide-protected D- or L-amino acid acceptors which allow access to α- or β-anomers in excellent yields (72-96%) and selectivity (∼100%) when appropriate C-2 substitution is installed. The glycoamino acid intermediates were divergently converted to Tn-based carboxylates or to hydrazides by tandem Pd-C debenzylation followed by treatment with hydrazine hydrate or hydrazine hydrate treatment alone.
authors.affiliation: Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States.
authors.forename: Ahmad Ali
authors.initials: AA
authors.lastname: Shaik
authors.affiliation: Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States.
authors.forename: Sharmeen
authors.initials: S
authors.lastname: Nishat
authors.affiliation: Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Andreana
mesh_terms: D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry*; D001688:Biological Products / Q000138:chemical synthesis* / Q000737:chemistry; D006031:Glycosylation; D006834:Hydrazines / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D001688:Biological Products; D006834:Hydrazines; C040286:Tn antigen