Reactant for preparation of β-carbolines via diastereo- and enantioselective Bronsted acid catalyzed N-acyliminium cyclization cascades 1 Reactant for preparation of substituted tetrahydro-β-carbolines as potential agents for treatment of human papillomavirus infection (HPV) 2 Reactant for asymmetric synthesis of nitrogen heterocycles via Bronsted acid-catalyzed N-acyliminium cyclization cascade 3 Reactant for amidation reactions 4 Reactant for preparation of potent β3-adrenergic receptor agonists 5 Reactant for preparation of tryptamine-based sulfonamides as potent and selective inhibitors of 15-lipoxygenase 6