Hussein, K. A. A.; Kassium, Y. A. Synthesis and Characterization of Some New 2- and 6- Substituted of 5- Acetyl - 4- (P- Phenyl) Pyrimidine and Substituted Thieno [2, 3- D] Pyrimidine. Univ. Aden J. Nat. and Appl. Sc. 2021, 25, 273-282.