Elsom, L. F. published the artcilePyrrole studies. XIV. Spectroscopic characteristics of cyanopyrroles, COA of Formula: C7H8N2, the publication is Journal of the Chemical Society [Section] B: Physical Organic (1970), 79-81, database is CAplus.
Data for pyrroles containing Me and CN groups show that the NH stretching frequency may be represented by the equation: νNH(cm-1) = 3496 – 9nαMe + 2nβMe – 22nαCN – 12nβCN, where nα and nβ are the number of substituents in the α- and β-positions resp. The electronic spectra indicate that in the excited state the resonance stabilization by the α-CN group is greater than that of the β-CN group to the extent of about 10.5 kcal/mole.
Journal of the Chemical Society [Section] B: Physical Organic published new progress about 26187-28-0. 26187-28-0 belongs to nitriles-buliding-blocks, auxiliary class Pyrrole,Nitrile, name is 2,4-Dimethyl-1H-pyrrole-3-carbonitrile, and the molecular formula is C7H8N2, COA of Formula: C7H8N2.
Referemce:
https://en.wikipedia.org/wiki/Nitrile,
Nitriles – Chemistry LibreTexts