The infrared absorption spectra of five N-glycopyranosylacetamides and of six acetate esters thereof are presented, together with the spectra of five related compounds, for the range of 5000 to 250 cm-1. Analysis of the spectra permitted assignment of characteristic group-frequencies. For comparison, the spectra of eight reducing, pyranose acetates are also given. The general effect (on the spectra) of changing the anomeric group from hydroxyl to (a) acetamido and (b) methoxyl, when all (other) hydroxyl groups are acetylated, is pointed out.