Processes and intermediates useful in the preparation of bronchodilator compounds of the formula ##STR1## wherein R is hydrogen, methyl or hydroxymethyl are described. Those compounds wherein R is H or CH.sub.3 have been found to have further utility as intermediates for pirbuterol (wherein R is hydroxymethyl).
Intermediates for preparing pirbuterol and analogs
申请人:Pfizer Inc.
公开号:US04632992A1
公开(公告)日:1986-12-30
Processes and intermediates useful in the preparation of bronchodilator compounds of the formula ##STR1## wherein R is hydrogen, methyl or hydroxymethyl are described. Those compounds wherein R is H or CH.sub.3 have been found to have further utility as intermediates for pirbuterol (wherein R is hydroxymethyl).
Pirbuterol is prepared by heating 5-hydroxy-2-(1-hydroxy-2-t-butylaminoethyl)pyridine with aqueous formaldehyde in the presence of a weak base, e.g. triethylamine. The pirbuterol is conveniently isolated as the hydrochloride. Pirbuterol is a well known bronchodilator.