Synthesis, Chemistry, and Biological Properties of Thienopyrimidines

Various aspects of the chemistry and biology of thienopyrimidines are described in the chapter. The chapter attempts to group the ring syntheses according to the type of starting material used and thienopyrimidine produced. The most widely used method for the synthesis of thieno[2,3-d]pyrimidines is condensation of 2-aminothiophene-3-carboxylates with reagents that provide the remaining C−N fragment required for pyrimidine fusion. The majority of thieno[3,2-d]pyrimidines are synthesized from alkyl 3-aminothiophene-2-carboxylates. The C−N fragment required for pyrimidine fusion is introduced either directly or stepwise. A general approach to the synthesis of thieno[3,4d]pyrimidines comprises the reaction of alkyl 3-aminothiophene-4-carboxylates with electrophilic and/or nucleophilic reagents that furnish the remaining C and N atoms of the pyrimidine ring. The chapter presents reactions, physicochemical properties, and the applications of thieno[2,3-d]pyrimidines, thieno[3,2-d]pyrimidines, and thieno[3,4-d]pyrimidines.