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Syntheses of organic compounds earned Kurt Alder and Otto Diels the Nobel Prize. Their work focused on the development of the Diels-Alder reaction, a powerful tool for constructing complex organic molecules. This reaction involves the cycloaddition of a conjugated diene with a dienophile, forming a cyclic product. The Diels-Alder reaction has found wide application in organic synthesis, particularly in the construction of natural products and pharmaceuticals.