A novel solid-phase approach to 2,4-diaminothiazoles.
A novel solid-phase synthesis of a 2,4-diaminothiazole library starting from a polymer-bound thiouronium salt is described. The synthetic strategy involves formation of polymer-bound thioureido-thiourea intermediates [5] which by treatment with alpha-bromo-ketones [6] undergoes S-alkylation, followed by a base-catalyzed intramolecular-ring closure/cleavage to give 2,4-diaminothiazoles [8]. This strategy tolerates a wide range of functionality and protecting groups. The novel feature of our method is a polymer-supported auto-scavenging strategy (PSAS), which provides a clean, high-yielding, and traceless synthesis to 2,4-diaminothiazoles.
Alkylation↗