Synthesis of 1,3-disubstituted quinazolin-2,4-diones

Taking into account these arguments. Smith et aimed to develop a solid-phase approach to 

3-disubstituted quinazolinediones which would not leave an extraneous polar resin-tethering substituent on the resulting molecules which might compromise CNS penetration. 

In a further example where cleavage is induced during final cyclisation step, DeWitt et developed a solid-phase protocol for the synthesis of tricyclic systems of type 295 which in addition are known to be inhibitors of cholesterol-O-acetyltransferase. 

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