Design and Microwave Assisted Synthesis of Coumarin Derivatives as PDE Inhibitors

Scheme 1

Synthetic route for title compounds 5a–x, where 5a; R = -H, X = -H, Y = H, 5b; R = -H, X = 6-Cl, Y = H, 5c; R = -H, X = 6-CH₃, Y = H, 5d; R = -H, X = 6-NO₂, Y = H, 5e; R = -H, X = 6-Br, Y = N, 5f; R = -H, X = 5,7-dimethyl, Y = H, 5g; R = -6Cl, X = -H, Y = H, 5h; R = -6Cl, X = -4Cl, Y = H, 5i; R = -6Cl, X = -CH₃, Y = H, 5j; R = -6Cl, X = 6-NO₂, Y = H, 5k; R = -6Cl, X = 6-Br, Y = N, 5l; R = -6Cl, X = 5,7-dimethyl, Y = H, 5m; R = -6Br, X = -H, Y = H, 5n; R = -6Br, X = -4Cl, Y = H, 5o; R = -6Br, X = -CH₃, Y = H, 5p; R = -6Br, X = 6-NO₂, Y = H, 5q; R = -6Br, X = 5-Br, Y = N, 5r; R = -6Br, X = 5,7-dimethyl, Y = H, 5s; R = 8-OCH₃, X = -H, Y = H, 5t; R = 8-OCH₃, X = 4-Cl, Y = H, 5u; R = 8-OCH₃, X = 6-CH₃, Y = H, 5v; R = 8-OCH₃, X = 6-NO₂, Y = H, 5w; R = 8-OCH₃, X = 5-Br, Y = N, 5x; R = 8-OCH₃, X = 5,7-dimethyl, Y = H.