Scheme 3.
Synthesis of d-glucose-derived ligands: methyl α-d-glucopyranoside 2,3,6-trisphosphate (5) and methyl α-d-glucopyranoside 2,4,6-trisphosphate (4)a
aReagents and conditions: (a) MeOH, reflux, 5d (b) (1) TMSCl, py, 22h (2) DCM, benzaldehyde, Fe(II)Cl2·6H2O, MeCN, triethylsilane, 0°C - room temperature, 1.5h (c) MeOH, H2O, 1M HCl (aq), reflux, 3h (d) (1) DCM, 5-phenyl-1H-tetrazole, (BnO)2PN(iPr)2, 20h (2) mCPBA, - 78°C - room temperature (e) MeOH:H2O (10:1 v/v), cat. Pd(OH)2/C, H2, 24h (f) MeCN, benzaldehyde dimethyl acetal, cat. CSA, 24h (g) BH3-THF, La(Tf)3, 7d.