Combinatorial Solid-Phase Synthesis of Structurally Complex Thiazolylhydantoines

A nine-step (!) solid-phase synthesis and subsequent cleavage with cyclization from the polymeric support were the keys to preparing high-quality molecular libraries of thiazolylhydantoines 1 from modified amino acid building blocks. Each step in the synthesis is different. Because the final cyclization cleaves only molecules that have been successfully constructed, the products obtained are pure. R¹, R²=alkyl; R³=aryl, arylO; R⁴=allyl.