Ingrid 't Hart

87 Chemical synthesis of sulfoglycolipid analog SM1a-core3 4 dd, J = 10.0, 8.4 Hz, H-2, β), 5.56 (1H, dd, J = 9.1, 4.5 Hz, H-2, α), 4.87 – 4.79 (1.5H, m, J = 18.7, 12.6 Hz, CH H α, β), 4.66 – 4.57 (1.5H, m, CH H α, β), 4.56 – 4.53 (3H, m, CH 2 , α, β), 4.39 – 4.35 (1H, m, H-5, α), 4.22 (1H, dd, J = 9.2, 4.6 Hz, H-3, α), 3.99 – 3.94 (0.5H , m, H-5, β), 3.77 (0.5H, dd, J = 9.5, 4.8 Hz, H-3, β), 3.72 – 3.57 (3H, m, H-6 α, β), 2.92 – 2.60 (6H, m, 2x CH 2 , Lev, α, β), 2.18 (s, 1.5H, CH 3 , Lev, β), 2.16 (s, 3H, CH 3 , Lev, α). 13 C NMR (151 MHz, CDCl 3 ) δ 206.3 (H 3 C-C =O, Lev), 172.0 (O- C =O, Lev), 165.6 (C=O, Bz), 160.5 (C=NH), 137.7, 134.7, 133.0, 129.9, 128.5, 128.4, 128.3, 128.3, 128.2, 128.2, 127.9, 127.6, 127.2, 126.3, 126.1, 96.4 (C-1, β), 94.2 (C-1, α), 75.9 (C-3, β), 73.8 (CH 2 ), 73.5 (C-5, β), 72.1 (C-3, α), 71.3 (CH 2 , α) , 71.0 (CH 2 , β), 70.7 (C-5, α), 69.9 (C-2, β), 69.1 (C-2, α), 67.6 (C-6, α), 67.3 (C-6, β), 67.0 (C-4, α), 66.0 (C-4, β), 38.1 (CH 2 , Lev), 29.8 (CH 3 , Lev), 28.1 (CH 2 , Lev). Scheme S2. Chemical glycosyla�on of galactose donor 7 and disaccharide acceptor 11 to form trisaccharide 14 . Lev removal on compound 14 formed the trisaccharide acceptor 4 . Reagents and condi�ons: (a) TMSOTf, CH 2 Cl 2 , 4 Å MS, -70 °C; (b) NH 2 NH 2· HOAc, CH 2 Cl 2 /MeOH, 50 °C. N -(Benzyl)-benzyloxycarbonyl-5-aminopentyl 2- O -benzoyl-6- O -benzyl-4- O -levulenoyl- 3- O -(2-naphthyl)methyl-β-D-galactopyranoside-(1→4)-3,6-di- O -benzyl-2-deoxy-2- phthalimido-β-D-glucopyranosyl-(1→3)-2-azido-4,6- O -benzylidene-2-deoxy-α-D- galactopyranoside (14) . A mixture of acceptor 11 (234 mg, 0.22 mmol) and donor 7 (231 mg, 0.31mmol) and 4 Åmolecular sieves was s�rred in DCM (3 mL) for 3 h. The reac�on mixture was cooled to -70°C and a solu�on of TMSOTf (4 µL, 0.022 mmol) in DCM (100 µL) was added. A�er 1 h Et 3 N was added and the reac�on mixture was concentrated in vacuo . The obtained residue was purified by SX1 size exclusion chromatography (Toluene:Acetone 1:1 v/v), followed by silica column chromatography using Toluene:EtOAc (1:0 to 4:1 v/v) as the eluent to afford compound 14 (256 mg, 70 %). 1H NMR (600 MHz, CDCl 3) δ 7.90 (2H, d, J = 7.4 Hz, H-Ar), 7.77 – 6.84 (44H, m, H-Ar), 5.69 (1H, d, J = 3.1 Hz, H-4, Gal-III), 5.40 (1H, dd, J = 9.8, 8.1 Hz, H-2, Gal- III), 5.32 – 5.26 (2H, m, C H -C 6 H 5 ; H-1, GlcNAc-II), 5.15 (2H, d, J = 7.6 Hz, CH 2 ), 4.88 (1H, d, CH H ), 4.80 – 4.71 (2H, m, CH H ; H-1, GalNAc-I), 4.64 (1H, d, J = 8.0 Hz, H-1, Gal-III), 4.56 – 4.20 (m, 10H, CH H ; CH 2 ; CH H ; CH 2 ; CH H ; H-3, GlcNAc-II; H-4, GalNAc-I; H-2 GlcNAc-II), 4.08 – 3.97 (2H, m, J = 9.3 Hz, CH H ; H-6a, GalNAc-I), 3.91 (1H, s, H-4, GlcNAc-II), 3.84 (1H, d, J = 9.4 Hz, H-3, GalNAc-I), 3.67 – 3.08 (14H, m, H-5, Gal-III; H-6b, GalNAc-I; H-3, Gal-III; H-6, GlcNAc-II; H-2, GalNAc-I; H-5, GlcNAc-II; H-6, Gal-III; H-5, GalNAc-I; CH 2 , pentyl, CH 2 , pentyl), 2.84 – 2.58 (4H, m, 2x CH 2 , Lev), 2.09 (3H, s, CH 3 , Lev), 1.45 (4H, d, J = 33.3 Hz, 2x CH 2 , pentyl), 1.18 (2H, d, J = 36.3 Hz, CH 2 , pentyl). 13 C NMR (151 MHz, CDCl 3 ) δ 206.1 O NPhth O BnO BnO O N 3 O O O O NBnCbz Ph O OBn LevO NapO OBz O OBn LevO NapO OBz O CCl 3 NH O NPhth HO BnO BnO O N 3 O O O O NBnCbz Ph a + O NPhth O BnO BnO O N 3 O O O O NBnCbz Ph O OBn HO NapO OBz b 7 11 14 , 70% 4 , 90% O NPhth O BnO BnO O N 3 O O O O NBnCbz Ph O OBn LevO NapO OBz