1-(3,4,5-Trimethoxybenzyl)-6,7-dibenzyloxy-3,4-dihydroisoquinoline Hydrochloride is an intermediate used in the synthesis of S-(-)-Tretoquinol Hydrochloride (T798100), which belongs to the class of adrenergic inhalants, selective β-2-adrenoreceptor agonists. S-(-)-Tretoquinol is used in the treatment of obstructive airway diseases. S-(-)-Tretoquinol is a bronchodilator.