... 373 / Heterocyclic Chem., 24, 373 (1987 ... 374 H. Morita and S. Shiotani Vol. ... broad) and v CN at 2210 cm"1. In the 'H nmr spectrum the signals of protons attached to the pyri- dine ring appeared at 5 6.53 (d, J = 8.4 Hz, IH, H-4), 7.81 (d, J = 1.4 Hz, IH, H-2) and 7.90 (dd, J = 1.4, 8.4 ...