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Epimers Switch Galectin-9 Domain Selectivity: 3N-Aryl Galactosides Bind the C-Terminal and Gulosides Bind the N-Terminal.

ABSTRACT: A series of 3-deoxy-3-N-arylated-?-d-galactoside and -guloside derivatives have been synthesized by cesium fluoride/trimetylsilylaryl triflate-mediated benzyne generation and N-arylation of 3-deoxy-3-amino-?-d-galactosides and -gulosides, respectively. Evaluation as ligands to galectin-1, 2, 3, 4N (N-terminal domain), 4C (C-terminal domain), 7, 8N, 8C, 9C, and 9N revealed that the galactosides selectively bound galectin-9C, whereas the gulosides selectively bound galectin-9N. Hence, the N-aryl group induces galectin-9 selectivity and the ligand 3C-configuration acts as an epimeric selectivity switch between the two domains of galectin-9. Furthermore, MD simulations revealed that galacto derivatives in galectin-9C and gulo derivatives in galectin-9N find stable poses with specific interactions, which proposes a possible explanation to the gal/gulo 9C/9N selectivity.

SUBMITTER: Mahanti M

PROVIDER: S-EPMC6956361 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Epimers Switch Galectin-9 Domain Selectivity: 3N-Aryl Galactosides Bind the C-Terminal and Gulosides Bind the N-Terminal.

Mahanti Mukul M Pal Kumar Bhaskar KB Sundin Anders P AP Leffler Hakon H Nilsson Ulf J UJ

ACS medicinal chemistry letters 20191204 1

A series of 3-deoxy-3-N-arylated-β-d-galactoside and -guloside derivatives have been synthesized by cesium fluoride/trimetylsilylaryl triflate-mediated benzyne generation and N-arylation of 3-deoxy-3-amino-β-d-galactosides and -gulosides, respectively. Evaluation as ligands to galectin-1, 2, 3, 4N (N-terminal domain), 4C (C-terminal domain), 7, 8N, 8C, 9C, and 9N revealed that the galactosides selectively bound galectin-9C, whereas the gulosides selectively bound gale ...[more]

PMID: 31938460

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