Résumé/Abstract Efficient methods for the Michael addition reactions of N-arylsulfonyl-3- phenylthiopiperidones (1) with both the protected amidoacrylates (4, 9) and the simple acrylates (12) have been developed. These reactions offer an efficient route to the 3-alkyl- substituted dihydropyridinones (3, 11), the dienophiles employed in the natural product synthesis