| abstract |
A process for preparing compounds of the formula <IMAGE> wherein R1, R2, R3 and R4 are independently selected from the group consisting of H, an alkyl group containing 1 to about 4 carbon atoms, an alkoxy group containing 1 to about 4 carbon atoms and halogen. The process involves reacting together a 2-aminopyridine, an alkyl tetrazol-5-ylacetate, and a trialkyl orthoformate and cyclizing the resulting intermediate. |