Trisaccharide reducing residue, removing

The reaction mixture was centrifuged (1450 X g), and the resultant clear supernatant was loaded onto a Cig column (5 g, 125 A) that had been pretreated with MeOH and conditioned with water (30 mL) prior to the loading of the centrifuged sample. The colurrm was washed with water (100 mL) then 1% acetonitrile (70 mL). The desired trisaccharide product was eluted with MeOH (HPLC grade, 120 mL). This eluate was concentrated under reduced pressure, and the product was dissolved in water (10 mL). This solution was passed through a Millex-GV filter (Millipore) to remove any residues of Cig resin. The filtrate was lyophilized to yield product as a fluffy white powder (133 mg, 196 mmol, 82%). NMR spectroscopy confirmed that the conversion was complete. 

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