<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A novel ring contraction of benzothiazine based methoxyamides is developed using an intramolecular AlCl<sub>3</sub>‐ or TiCl<sub>4</sub>‐promoted Friedel—Crafts reaction to give tetracyclic lactams.</p> </abstract>