Oxitropium bromide

Oxitropium bromide (trade names Oxivent, Tersigan) is an anticholinergic used as a bronchodilator for the treatment of asthma and chronic obstructive pulmonary disease.

It was patented in 1966 and approved for medical use in 1983.

Synthesis

 * Oxitropium synthesis.svg

The natural product, norscopolamine (1), is converted by two alkylation reactions into oxitropium bromide. The first, with bromoethane, gives the N-ethyl intermediate (2), which is treated with bromomethane.