The IR spectra have been recorded in the solid state for the parent molecule, 6-(N-pyrrolyl)purine (1) and itsN-9-andN-7-substituted derivatives: 9-and 7-(2-hydroxyprop-1-yl)-6-(N-pyrrol-1-yl)purine (2and3), 9-and 7-(2-acetoxyprop-1-yl)-6-(N-pyrrol-1-yl)purine (4and5), 9-and 7-(2,3-dihydroxyprop-1-yl)-6-(N-pyrrol-1-yl)purine (6and7) as well as 9-and 7-(2,3-diacetoxyprop-1-yl)-6-(N-pyrrol-1-yl)purine (8and9). Analysis of the characteristic bands has proved to be useful in differentiating betweenN-9 andN-7 regioisomers.