| 摘要 |
A process for the preparation of a compound of the formula:; <CHEM> or a pharmaceutically acceptable acid addition salt thereof, wherein R is hydrogen, methyl or hydroxymethyl which comprises treating a compound of the formula:- <CHEM> wherein R<1> is benzyl and R<2> is hydrogen or methyl, or R<1> and R<2> are taken together and are <CHEM> with hydrogen; or, alternatively, to produce a compound in which R is methyl or hydroxymethyl, solvolyzing the compound of the formula (V) in which R<1> and R<2> are taken together, followed by treatment with hydrogen; followed by, optionally, conversion of the product (1) into a pharmaceutically acceptable acid addition salt by reaction with a suitable acid. Pirbuterol (R = hydroxymethyl) is a well known bronchodilator. Also claimed are certain novel intermediates, including those of the formula (V). |
