Synthesis of New Polycyclic Compounds Containing Thieno[2′,3′:5,6]pyrimido[2,1-a]isoindole Fragment

The reaction of partially saturated derivatives of 3-aminothieno[2,3-b]pyridine-2-carboxamide with phthalic anhydride in acetic acid or DMF on heating leads to the formation of thieno[2′,3′:5.6]pyrimido[2,1-a]isoindole derivatives fused with a pyridine or quinoline core. One of the obtained compounds shows a pronounced UV fluorescence.