Abstract: Pyrrolidine main protease inhibitors are described that are effective as antiviral compounds.

Abstract: A tracheal tube with built-in vocalization capability including a neck piece having a bore disposed therethrough, ventilation holes disposed on the neck piece and around the bore, and a strap mechanism for securing the neck piece about a neck of a user to place the bore in general alignment with a stoma formed on the user's trachea; a rigid telescopically adjustable tubular throat piece with open ends bent in a general J-shaped configuration and having a lower straight portion insertable within the user's trachea through the stoma and an upper curved portion extended through the stoma and through the bore of the neck piece and secured to the neck piece; a flexible tubular first air line having an open distal free end, a sealed proximal end secured to an exterior surface of the throat piece, and a plurality of vent holes formed on the distal end for supplying air to vocal cords of the user; and a one-way air valve mechanism for controlling air flow through the first air line.