Catalytic Approaches to Optically Active 1,5-Benzothiazepines

The 1,5-benzothiazepine framework is well-known as a versatile pharmacophore, and its derivatives have numerous biological activities. Therefore, various synthetic routes to these important compounds have already been investigated. However, in light of the increase in optically active pharmaceuticals, it is of significance to also develop enantioselective synthetic methods. Among various strategies, methods based on enantioselective catalysis are generally efficient in both academia and industry with respect to different factors such as atom or step economy, economic reasons, and diversity-oriented synthesis. While various methodologies had already been investigated until the 1990s, soon after the discovery of marketed pharmaceuticals such as diltiazem, a blockbuster drug containing a 1,5-benzothiazepine unit, additional catalytic strategies also appeared. Thus, this Perspective provides an account of the progress on enantioselective catalysis for the asymmetric synthesis of 1,5-benzothiazepine derivatives.