“…[17][18][19][20][21] For 2,7-di(hetero)aryl substituted pyrimido[4,5-g]quinazoline-4,9-diones, only the synthesis of 2,7-diphenylpyrimido[4,5-g]quinazoline-4,9-dione was reported. 22 They used 2,5-diaminoterephthalic acid as a starting material to prepare 2,7-diphenylpyrimido[4,5-g]-quinazoline-4,9-dione with several routes. Unfortunately, synthetic details were limited.…”