... J. Heterocyclic Chenr., 18, 1149 (1981). Since the pioneering work by Huisgen on azomethine ... 12 Table I1 Chemical Shifts and Substituent Chemical Shifts for the Pyrazolo[l,5-a]pyridines (c) R'. R' ... Page 4. 1152 PL Anderson, J. P. Hasak, A. D. Kahle, NA Paolella and MJ Shapiro ...