Question

in an experiment, 83 mg of glycogen were exhaustively methylated and then acid hydrolyzed. the methylated products were separated and quantified. Exactly 63.2 micromoles of 2,3-dimethylglucose were obtained. What percent (to two figures) of the total glucose residues are branch points?

Answer 1

mass of 2,3-dimethylglucose = moles x molar mass

                                              = 63.2 x 208.21/1000

                                              = 1.315 mg

Percent of total glucose residues are branch points = 1.315 x 100/83 = 1.58%