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Use Trichloroisocyanuric Acid (TCCA) to synthesis something

Trichloroisocyanuric Acid (TCCA) (410 mg, 1.77mmol, 1 equiv) was added to it. Then TMSOTf (0.096 mL, 0.53 mmol, 0.3 equiv) was added via a micro-syringe. After the acceptor was consumed completely (checked by TLC), the reaction mixture was filtered off through Celite bed, and the bed was washed with CH2Cl2. The combined filtrate and washings was washed subsequently with saturated NaHCO3 solution and water. The organic layer was dried over anhydrous Na2SO4 and concentrated to afford the glycosylated product. The crude mass was purified by silica gel column chromatography (60-120 mesh) (PE/EtOAc 3:1) to get pure product (10, 1.89 g) as colourless syrup in 96% yield.[α]29 D -2.57 (c 7.0, CHCl3); 1H NMR (500 MHz, CDCl3): δ 1.68- 1.76 (bs, 2H), 1.97 (s, 3H, COCH3), 3.24 (m, 1H), 3.33-3.37 (m,3H), 3.38-3.43 (m, 2H), 3.46 (m, 1H), 3.55-3.59 (m, 2H), 3.69 (d,1H, J = 10.0 Hz), 3.74-3.77 (m, 2H),3.85 (m, 1H), 3.9 (d, 1H, J =2.5 Hz), 3.95 (t, 1H, J = 9.0 Hz), 4.23 (d, 1H, J = 12.0 Hz), 4.29-4.34 (app t, 2H, J = 10.5, 11.5 Hz), 4.36-4.38 (dd, 2H, J = 1.5, 9Hz), 4.48 (d, 1H, J = 12.0 Hz), 4.53-4.59 (dd, 2H, J = 11.5, 19.0Hz), 4.67-4.77 (m, 3H), 4.82 (d, 1H, J = 11.0 Hz), 4.94-4.98 (m,3H), 5.08 (bs, 2H), 5.29 (bs, 1H), 7.19-7.36 (m, 35H, ArH). 13CNMR (75 MHz, CDCl3): δ 20.9, 29.5, 38.2, 66.5, 66.7, 68.1, 68.3,72.5, 72.6, 73.1, 73.5, 73.7, 74.3, 74.7, 75.3, 79.9, 80.8, 82.5,100.8 (C-1), 102.9 (C-1’), 127.2, 127.4, 127.5, 127.57, 127.62,127.7, 127.9, 128.0, 128.1, 128.2, 128.3, 128.3, 128.4, 128.5,136.9, 138.1, 128.2, 138.5, 138.8, 139.0,
139.1, 156.6 (C=O),169.6 (C=O). HRMS (TOF): calc for (M + Na)+ C67H73NO14Na1138.4929, found 1138.4932.
A suspension of 14 (1.0 g, 1.6 mmol) and Trichloroisocyanuric Acid (TCCA) (372 mg, 1equiv.) in (CH3)2CO-H2O (4:1) was kept on stirring at 0 °C for 30minutes. After completion of the reaction (indicated by TLC)(CH3)2CO was evaporated in vacuo, and the resulting mixture was diluted with CH2Cl2 (15 mL). The solution was washed subsequently with saturated aqueous NaHCO3 (200 mL) and water. The organic layer was dried over anhydrous Na2SO4 and concentrated. The residue was filtered through a column of silica gel (eluent: PE/EtOAc, 4:1) to afford 2-O-acetyl-3,4,6-tri- O-benzyl-D-mannopyranose 6 as white foam (808 mg, 96%). 1HNMR (300 MHz, CDCl3): δ 2.16 (s, 3H, COCH3), 3.59-3.78 (m,5H), 4.03-4.11 (m, 2H), 4.47-4.66 (m, 4H), 4.73 (m, 1H), 4.86(m, 1H), 5.22 (t, 1H, J = 1.5 Hz), 5.38 (m, 1H), 7.15-7.18 (m, 2H,ArH), 7.27-7.37 (m, 15H, ArH). HRMS (TOF): calc for (M + Na)+C29H32O7Na 515.2046, found 515.2040.
This experiment use Trichloroisocyanuric Acid (TCCA). Expeditious syntheses of the tetrasaccharide cap related to the lypophosphoglycan of Leishmania donovani from two monosaccharides and a disaccharide building blocks were achieved by one-pot sequential glycosylation reactions. The monosaccharide building blocks were synthesized from D-mannose, and the disaccharide building block was prepared from lactose by C2-epimerisation of its glucose unit through C2 hydroxy oxidation-reduction.