Pyridine intermediates, useful in the synthesis of beta-adrenergic receptor agonists

摘要

The present invention relates to certain compounds of the formula (I), which are useful in the synthesis of certain β-adrenergic receptor agonists. The invention also relates to a process for synthesizing the compounds of formula (I) and to compounds of the formula (II), wherein R¹, R² and R⁴ are defined herein, which are useful in the synthesis of the compounds of formula (I). The invention also relates to a process for synthesizing a compound of formula (II). The invention further relates to processes for synthesizing compounds of formula (Z*), R¹, R² and Y^2* are defined herein.