<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Tubuvalin derivatives are prepared by a regio‐ and enantioselective L‐proline‐catalyzed aldol reaction of thiazole carbaldehydes with acetone and a corresponding prolinamide‐catalyzed transformation of 2‐formylthiazole‐4‐carboxylate with methylisopropyl ketone on water.</p> </abstract>