chemoenzymatic regioselective acylation of Neu5Ac followed by SmI2-mediated (1:1) diastereomers at the newly formed hydroxymethylene bridge stereocenter. of primary amino end groups in purchased beads to carbonyl end groups in 8. Attachment of Neuraminic Acid to Solid Support (9) Beads 8 were dried under vacuum before starting the reaction. Beads (1 g 0.2 mmol) were suspended in DMF (7 mL) and stirred for 1 h under argon after which CCG-63802 time DCC (206 mg 1 mmol) was added. In a separate flask 6 (188 mg 0.4 mmol) was dissolved in DMF (0.5 mL) and HOBt (135 mg 1 mmol) and triethylamine (92 μL 0.6 mmol) were added. The mixture was stirred until the HOBt dissolved. This mixture was transferred to bead suspension at 0 °C and the reaction was stirred at 0 °C for 2 h. The reaction was warmed to room temperature and stirred overnight. The beads were washed four times (10 mL × 4) with DMF DCM MeOH acetone and DCM. The resulting beads were vacuum-dried and the above procedure was repeated two more times. The residual carboxyl groups were blocked using the same immobilization procedure except that at this time 6 was replaced with 1 mmol of propylamine and 1 mmol of DCC CCG-63802 and reacted for 5 h. The beads 9 were washed and dried. Chlorination of 9 CPG-bound 9 (1 g) was added to acetyl chloride (5 mL) MeOH (0.2 mL) and acetic acid (0.4 mL). The mixture was stirred at room temperature for 2 d washed with DCM acetone MeOH and DCM and dried to generate 0.5 MeOH); HRMS calcd for C27H35NO9Na [M + Na]+ 540.2210 found 540.2234 [M + Na]+. Methyl 5-acetamido-4 7 8 9 tetra-= 4.5 7.4 12.6 Hz) 4.26 (dd 1 = 2.1 12.7 Hz) 4.17 (m 3 3.66 (s 3 COOC= 4.5 12.7 Hz) 2.24 2.19 2.05 1.99 1.87 (5s 5 × 3H COC= 12.7 12.7 Hz); 13C NMR (400 MHz CDCl3) δ 171.1 170.7 170.2 170.1 169.9 136.9 136.8 131.4 131.3 127.9 127.8 126.5 126.3 86.6 77.6 73.4 70.4 68.4 67.7 62.5 52.4 49.3 40.9 40.6 33.3 23.2 21.3 20.9 20.9 20.7 14.1 [α]20D ?5.5 (0.9 CHCl3); HRMS calcd for C35H43N O13Na [M + Na]+ 708.2632 found Acvrl1 708.2632 [M + Na]+. Methyl 5-acetamido-3 5 1 δ 3.86-3.38 (m 14 3.78 (2s 6 COOCH3) 2.5 (dd 1 = 4.5 Hz and = 13.5 Hz) 2.42 (dd CCG-63802 1 = 4.5 and = 13.25) 2.02 (t 1 = 11.5 Hz) 2 (s 6 NHCOCH3) 1.75 (t 1 = 11 Hz) 1.65 (m 2 1.48 (m 12 0.9 (m 6 13 NMR (500 MHz MD3OD) (= 1:1) δ 174.8 174.4 85.5 84.7 76.6 76.1 75.8 75.5 72.8 72.5 70.4 70.2 69.2 64.7 64.7 54.2 54.1 53.1 53.1 49.9 38 35.7 32 31.5 30.8 29.6 29.5 23.5 23.5 22.7 22.7 14.8 ESI-MS 394.1 [M + H]+ 416.1 [M + Na]+; HRMS calcd for C17H31NO9Na [M + Na]+ 416.4184 found 416.1888 [M + Na]+. Methyl 5-acetamido-4 7 8 9 tetra-= 1:1) δ 5.46 (m 2 5.42 (dt 1 = 2.5 8 Hz) 5.38 (dt 1 = 2.5 8 Hz) 5.14 (m 2 NH) 4.8 (m 2 4.38 (dd 1 = 4.5 12.5 Hz) 4.34 (dd 1 = 4.5 12.5 Hz) 4.21 (m 6 3.8 (2s 6 OCH3) 2.53 (dd 1 = 4.5 14.2 2.45 (dd 1 = 4.5 12.5 Hz) 2.37 (dd 1 = 4.5 12.5 2.18 2.16 2.15 2.14 2.13 2.09 2.06 2.03 1.91 1.87 (10s 30 COCH3) 1.85 (m 1 1.7 (m 2 1.5 (m 12 0.9 (m 6 13 NMR (500 MHz CDCl3) (= 1:1) δ 171.4 171.32 171.3 171.2 171.14 171.12 75.7 73.5 73.4 71.9 71.8 70.3 70 69.2 68.9 68.8 68 67.9 63.1 62.99 62.97 52.5 49.7 49.6 34.7 33.5 32 30.6 28.6 28.4 28.2 23.4 23.3 22.7 22.6 21.4 21.13 21 20.9 15.8 ESI-MS 561.2 [M + H]+; HRMS calcd for C25H39NO13Na [M + Na]+ 584.5651 found 584.2328 [M + Na]+. Methyl 5-acetamido-3 5 1 δ 3.82 (2s 6 COOCH3) 3.85 (m 14 2.53 (m 2 2.01 (s 6 NHCOC= 1:1) δ 174.9 166.8 87.9 79.7 79.4 76.9 75.8 73 72.9 70.5 69.6 64.7 64.6 54.1 53.2 47.5 CCG-63802 36.6 36 31.8 31.6 28.4 28 26.6 26.1 22.7 21.9 ESI-MS 460.3 [M + H]+ 482.2 [M + Na]+; HRMS calcd for C22H38NO9 [M + H]+ 460.5385 found 460.2556 [M +..