He product, which was purified by gel chromatography to be able to get rid of residual sodium acetate. For experimental data of compounds six – 18 and 32 – 33 and NMR spectra of compounds five 18, 20 – 24 and 26 – 33 refer to Supporting Information and facts. Methyl (four,five,7,8-tetra-O-acetyl-3-deoxy-3-iodo-D-glycero–D-talo-oct-2ulopyranosyl)onate fluoride (five)–A resolution of 4[19] (0.75 g, 1.275 mmol) in dry CH2Cl2 (13.0 mL) was treated with hydrogen fluoride pyridine ( 70 HF, 30 pyridine; 4.0 mL) at 0 for 2.five h inside a sealed Teflon flask. Ice-cold water (ten mL) was added, the phases had been mixed thoroughly and separated. The aqueous phase was once once again extracted with CH2Cl2 plus the combined organic extracts had been washed with aq. NaHCO3, dried (MgSO4), filtered and concentrated. The crude product was speedily purified by flash chromatography (n-hexane/EtOAc 1:1) affording five (0.67 g, 96 ) as a colorless oil; []D20 + 18.eight (c 0.76, MeOH); Rf 0.51 (toluene/EtOAc two:1); 1H NMR (CDCl3): 5.47 (ddd, 1H, J5,four 3.five, J5,six 1.9, J5,three 0.eight Hz, H-5), five.37 – 5.34 (m, 1H, H-7), 4.97 (dd, 1H, J4,three five.1 Hz, H-4), 4.64 (app dt, 1H, H-3), four.52 (dd, 1H, J8a,8b 12.four, J8a,7 two.three Hz, H-8a), four.49 (dd, 1H, J6,7 9.8 Hz, H-6), 4.23 (dd, 1H, J8b,7 4.two Hz, H-8b), three.88 (s, 3H, CO2CH3), two.12, 2.07, two.05 and 1.98 (four s, every 3H, COCH3); 13C NMR (CDCl3): 170.42, 169.90, 169.36 and 169.17 (4 s, COCH3), 163.29 (ds, J1,F 28.two Hz, C-1), 108.92 (ds, J2,F 231.1 Hz, C-2), 70.15 (dd, J6,F 4.5 Hz, C-6), 67.11 (d, C-7), 64.56 (d, C-4), 62.76 (d, C-5), 61.84 (t, C-8), 53.49 (q, CO2CH3), 20.79, 20.66, 20.61 and 20.51 (four q, COCH3), 18.02 (dd, J3,F 31.three Hz, C-3); 19F NMR (CDCl3): -103.00 (d, JF,H-3 five.4 Hz); ESI-TOF HRMS: m/z = 566.0533; calcd for C17H22FIO11NH4+: 566.0529.Chemistry. Author manuscript; available in PMC 2016 February 26.Pokorny and KosmaPageMethyl (four,5,7,8-tetra-O-acetyl-3-deoxy-3-iodo-D-glycero–D-talo-oct-2ulopyranosyl)onate-(24)[methyl (four,five,7,8-tetra-O-acetyl-3-deoxy-3-iodo-Dglycero–D-talo-oct-2-ulopyranosyl)onate-(28)]-methyl (methyl 3-deoxy–Dmanno-oct-2-ulopyranosid)onate (20)–A mixture of predried 19[18] (16.MCP-1/CCL2 Protein Molecular Weight three mg, 0.IFN-gamma Protein Synonyms 061 mmol) and 5 (80.6 mg, 0.147 mmol) in dry CH2Cl2 (4.0 mL) was treated with BF3.Et2O (120.7 L, 0.588 mmol) as outlined by the general procedure for glycosylation. Soon after 1 h the suspension was subjected to aqueous work-up as well as the crude product was purified by HPcolumn chromatography (toluene/EtOAc 2:11:1) yielding the glycal 3[17] (six.PMID:23546012 8 mg, 11 ), the slower migrating (24/7)-regioisomer trisaccharide (5.four mg, 7 ) and ultimately the slowest migrating trisaccharide 20 (47.0 mg, 58 ). (24/7)-trisaccharide: colorless oil: Rf 0.39 (toluene/EtOAc 1:1, HP-TLC); 1H NMR (CDCl3): 5.46 – 5.44 (m, 2H, H-5, H-5), 5.38 five.34 (m, 2H, H-7, H-7), 5.04 (dd, 1H, J4,3 four.six, J4,five 3.7 Hz, H-4), 4.97 (dd, 1H, J4,three four.8, J4,five three.6 Hz, H-4), four.74 (dd, 1H, J8a,8b 12.5, J8a,7 two.9 Hz, H-8a), four.71 (dd, 1H, J8a,7 12.five, J8a,7 two.eight Hz, H-8a), 4.69 (dd, 1H, J6,7 9.2, J6,5 two.two Hz, H-6), four.55 (dd, 1H, J3,five 0.eight Hz, H-3), four.47 (dd, 1H, J3,four 0.9 Hz, H-3), 4.26 – 4.22 (m, 2H, H-6, H-8b), four.17 – 4.11 (m, 2H, H-4, H-8b), 4.00 – three.97 (m, 1H, H-8a), three.94 – three.88 (m, 8H, H-7, H-8b, two CO2CH3), three.80 (s, 3H, CO2CH3), three.72 (dd, 1H, J6,7 five.2, J6,5 1.two Hz, H-6), three.63 – 3.61 (m, 1H, H-5), three.24 (s, 3H, OCH3), 2.64 (b s, 1H, C8-OH), two.49 (b s, 1H, C5-OH), 2.14 – two.11 (m, 11H, H-3ax, H-3eq, 3 COCH3), two.ten, two.07, 2.06, 1.98 and 1.979 (5 s, every 3H, COCH3). 20: colorless amorphous solid; []D20 + 63.1 (c 0.55, CHCl3); Rf 0.38 (toluene/EtOAc.