A concise, modular and efficient synthesis of the title natural products is reported. Prominent steps include (i) one-pot assembly of a key β-aryl-α-benzoylbutenolide building block by regiocontrolled "click-unclick" oxazole-ynone Diels-Alder cycloaddition/cycloreversion and ensuing 2-alkoxyfuran hydrolysis and (ii) a protecting group-free vinylogous Knoevenagel condensation enabling rapid access to cadiolides A, B, and D from a common precursor.