Synthesis and structure of (4R,5R)-α,α,α′,α′-2,2-hexaphenyl-4,5-dimethanol-1,3-dioxolane

Block Synthesis of Tetra- and Hexasaccharides (β-d-Glycero-d-manno-Hepp-(1→4)-[α-l-Rhap-(1→3)-β-d-glycero-d-manno-Hepp-(1→4)]n-α-l-Rhap-OMe (n = 1 and 2)) Corresponding to Multiple Repeat Units of the Glycan from the Surface-Layer Glycoprotein from Bacillus thermoaerophilus

“…The residue was purified by silica gel chromatography (AcOEt/hexane = 1/4 to 1/3, then AcOEt/ CH 2 Cl 2 = 3/1 to 2/1) to afford the monobenzylated ether 2 (12.21 g, 25.6 mmol, 81%). [α] D 24 = + 221.3 ( c 1.2, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.43–7.41 (m, 4 H), 7.35-7.26 (m, 6 H), 5.48 (s, 1 H), 4.93 (d, 1 H, J = 11.5 Hz), 4.68 (d, 1 H, J = 11.5 Hz), 4.29 (t, 1 H, J = 10.0 Hz), 4.25-4.22 (m, 1 H), 4.08 (dd, 1 H, J = 2.5, 9.5 Hz), 3.99 (br. s, 1 H), 3.85-3.77 (m, 2 H), 3.33 (s, 3 H), 3.30 (s, 3 H), 1.90 (br.…”

“…The residue was purified by silica gel chromatography (AcOEt/hexane = 1/15) to furnish alkene 4 (2.45 g, 5.17 mmol, 84%). [α] D 24 = + 251.7 ( c 1.3, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.45-7.41 (m, 4 H), 7.35-7.25 (m, 6 H), 6.02-5.95 (m, 1 H), 5.52 (s, 1 H), 5.45-5.42 (m, 1 H), 5.27-5.24 (m, 1 H), 4.91 (d, 1 H, J = 12.0 Hz), 4.71 (d, 1 H, J = 12.0 Hz), 4.63 (t, 1 H, J = 7.50 Hz), 4.09-4.03 (m, 2 H), 3.99 (m, 1 H), 3.33 (s, 3 H), 3.26 (s, 3 H), 1.38 (s, 3 H), 1.34 (s, 3 H); 13 C NMR (125 MHz, CDCl 3 ) δ 138.7, 134.8, 134.0, 131.6, 129.2, 128.5, 128.2, 127.8, 127.6, 118.1, 100.2, 100.0, 87.6, 77.8, 73.2, 72.3, 69.8, 67.8, 48.2, 48.1, 18.1, 18.0; HR-ESI m/z : calcd for C 26 H 32 O 6 NaS, 495.1817 [M+Na + ], Found C 26 H 32 O 6 NaS, 495.1826; and alkene 5 (58.1 mg, 112 µmol, 1.8%). [α] d 23 = + 218.3 ( c 0.97, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.43-7.38 (m, 4 H), 7.34-7.24 (m, 6 H), 6.45 (dd, 1 H, J = 1.0, 15.0 Hz), 5.47 (s, 1 H), 5.45 (dd, 1 H, J = 6.5, 15.5 Hz), 4.89 (d, 1 H, J = 12.5 Hz), 4.70 (d, 1 H, J = 12.0 Hz), 4.65 (t, 1 H, J = 7.5 Hz), 4.05-4.00 (m, 2 H), 3.96 (m, 1 H), 3.32 (s, 3 H), 3.25 (s, 3 H), 2.24 (s, 3 H), 1.36 (s, 3 H), 1.33 (s, 3 H); 13 C NMR (125 MHz, CDCl 3 ) δ 138.6, 134.8, 131.6, 129.8, 129.3, 128.5, 128.2, 127.8, 127.6, 120.4, 100.2, 100.0, 87.7, 77.8, 73.3, 72.4, 69.7, 68.0, 48.2, 48.0, 18.1, 18.0, 14.6; HR-ESI m/z : calcd for C 27 H 34 O 6 NaS 2 , 541.1695 [M+Na + ], Found C 27 H 34 O 6 NaS, 541.1675.…”

“…The collected organic phase was further washed with brine, dried over Na 2 SO 4 , and concentrated. The residue was subjected to silica gel chromatography (AcOEt/CH 2 Cl 2 = 1/4, then AcOEt/hexane = 1/1 and AcOEt/CH 2 Cl 2 = 2/5) to afford 6 (219.3 mg, 433 µmol, 59%), [α] D 24 = + 240.3 ( c 0.94, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.43-7.40 (m, 4 H), 7.35-7.26 (m, 6 H), 5.43 (s, 1 H), 4.91 (d, 1 H, J = 12.0 Hz), 4.67 (d, 1 H, J = 12.0 Hz), 4.37 (t, 1 H, J = 10.0 Hz), 4.26 (dd, 1 H, J = 6.0, 10.0 Hz), 4.07 (dd, 1 H, J = 3.0, 10.0 Hz), 3.96-3.93 (m, 2 H), 3.70-3.63 (m, 2 H), 3.33 (s, 3 H), 3.31 (s, 3 H), 3.16 (d, 1 H, OH, J = 3.0 Hz), 2.20 (t, 1 H, OH, J = 6.5 Hz), 1.36 (s, 3 H), 1.33 (s, 3 H); 13 C NMR (125 MHz, CDCl 3 ) δ 138.5, 133.7, 132.2, 129.4, 128.5, 128.2, 128.1, 127.9, 100.3, 100.2, 87.8, 77.5, 73.5, 73.4, 71.2, 69.4, 67.1, 63.2, 48.6, 48.3, 18.1, 18.0; HR-ESI m/z : calcd for C 26 H 34 O 8 NaS, 529.1872 [M+Na + ], Found C 26 H 34 O 8 NaS, 529.1859; 7 (18.3 mg, 34 µmol, 4.6%). [α] D 23 = + 148.7 ( c 0.78, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.93 (d, 2 H, J = 7.5 Hz), 7.69 (t, 1 H, J = 7.5 Hz), 7.58 (t, 2 H, J = 7.5 Hz), 7.44 (d, 2 H, J = 7.0 Hz), 7.37-7.31 (m, 3 H), 5.00 (d, 1 H, J = 11.5 Hz), 4.72 (s, 1 H), 4.67 (d, 1 H, J = 11.0 Hz), 4.61 (d, 1 H, J = 3.0 Hz), 4.52-4.49 (m, 2 H), 4.35 (t, 1 H, J = 9.0 Hz), 3.79-3.75 (m, 1 H), 3.57-3.52 (m, 2 H), 3.35 (s, 3 H), 3.33 (s, 3 H), 3.27 (br s, 1 H, OH ), 2.23 (br.…”

“…[α] D 23 = + 148.7 ( c 0.78, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.93 (d, 2 H, J = 7.5 Hz), 7.69 (t, 1 H, J = 7.5 Hz), 7.58 (t, 2 H, J = 7.5 Hz), 7.44 (d, 2 H, J = 7.0 Hz), 7.37-7.31 (m, 3 H), 5.00 (d, 1 H, J = 11.5 Hz), 4.72 (s, 1 H), 4.67 (d, 1 H, J = 11.0 Hz), 4.61 (d, 1 H, J = 3.0 Hz), 4.52-4.49 (m, 2 H), 4.35 (t, 1 H, J = 9.0 Hz), 3.79-3.75 (m, 1 H), 3.57-3.52 (m, 2 H), 3.35 (s, 3 H), 3.33 (s, 3 H), 3.27 (br s, 1 H, OH ), 2.23 (br. s, 1 H, OH ), 1.37 (s, 3 H), 1.35 (s, 3 H); 13 C NMR (125 MHz, CDCl 3 ) δ138.1, 136.7, 134.6, 129.5, 129.3, 128.6, 128.4, 128.1, 100.3, 100.1, 93.0, 74.7, 74.1, 73.9, 71.9, 69.1, 66.1, 62.4, 48.6, 48.4, 18.0, 17.9; HR-ESI m/z : calcd for C 26 H 34 O 10 NaS, 561.1770 [M+Na + ], Found C 26 H 34 O 10 NaS, 561.1748; 8 (101.0 mg, 199 µmol, 27%), [α] D 24 = + 232.2 ( c 1.1, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.43 (d, 1 H, J = 7.5 Hz), 7.38-7.28 (m, 8 H), 5.52 (s, 1 H), 4.95 (d, 1 H, J = 12.0 Hz), 4.67 (d, 1 H, J = 11.5 Hz), 4.42 (t, 1 H, J = 10.0 Hz), 4.14 (dd, 1 H, J = 2.0, 10.0 Hz), 4.08 (dd, 1 H, J = 3.0, 10.0 Hz), 3.97-3.95 (m, 1 H), 3.94-3.90 (m, 1 H), 3.50 (br. s, 2 H), 3.33 (s, 3 H), 3.32 (s, 3 H), 2.66 (d, 1 H, OH, J = 6.0 Hz), 1.85 (br s, 1 H, OH), 1.36 (s, 3 H), 1.33 (s, 3 H); 13 C NMR (125 MHz, CDCl 3 ) δ 138.5, 133.3, 132.1, 129.5, 128.6, 128.2, 127.9, 100.3, 100.0, 87.6, 77.3, 73.5, 72.9, 69.7, 68.8, 65.1, 63.4, 48.3, 18.1, 18.0; HR-ESI m/z : calcd for C 26 H 34 O 8 NaS, 529.1872 [M+Na + ], Found C 26 H 34 O 10 NaS, 529.1874; 9 (15.1 mg, 28 µmol, 3.8%).…”

“…The residue was purified by silica gel chromatography (AcOEt/Hexane = 1/6) to yield ether 10 (1.90 g, 3.19 mmol, 96%). [α] D 24 = + 186.5 ( c 1.2, CHCl 3 ); 1 H NMR (500 MHz, CDCl 3 ) δ 7.41-7.36 (m, 4 H), 7.34-7.23 (m, 11 H), 5.47 (s, 1 H), 4.89 (d, 1 H, J = 12.5 Hz), 4.67 (d, 1 H, J = 12.0 Hz), 4.53 (d, 1 H, J = 12.0 Hz), 4.48 (d, 1 H, J = 12.5 Hz), 4.36 (t, 1 H, J = 10.0 Hz), 4.20 (dd, 1 H, J = 5.0, 10.0 Hz), 4.13-4.10 (m, 1 H), 4.03 (dd, 1 H, J = 3.0, 10.5 Hz), 3.93-3.92 (m, 1 H), 3.57 (d, 2 H, J = 5.0 Hz), 3.30 (s, 3 H), 3.23 (s, 3 H), 2.84 (d, 1 H, OH, J = 2.5 Hz), 1.33 (s, 3 H), 1.28 (s, 3 H); 13 C NMR (125 MHz, CDCl 3 ) δ 138.6, 138.5, 134.3, 131.6, 129.3, 128.6, 128.2, 128.1, 127.9, 127.8, 127.7, 100.3, 100.0, 87.5, 77.5, 73.6, 73.3, 72.8, 71.0, 69.6, 65.9, 48.5, 48.3, 18.1, 18.0; HR-ESI m/z : calcd for C 33 H 40 O 8 NaS, 619.2342 [M+Na + ], Found C 33 H 40 O 8 NaS, 619.2323.…”