quinonic derivatives active against a virulent strain of toxoplasma gondii. synthesis of 2-methylfuro[2,3-g]- and [3,2-g]isoquinolinetriones

2-methylfuro[2,3-g]isoquinoline-4,7,9-trione (4) and 2-methylfuro[3,2-g]isoquinoline-4,6,9-trione (5) were prepared regiospecifically from 2-azadiene 9 and bromobenzofuran-4,7-diones 1 or 11. The activity of these two compounds and some other quinonic derivatives was evaluated in vitro against a virulent strain of Toxoplasma gondii. Compounds 4 and 7 were found to be as active as pyrimethamine. Figure 1. Structure and growth inhibition % (GI) of the compounds tested against T. gondii at the concentration of 2 μg/mL (a) or 0.1 μg/mL (b). Scheme 1. i: (1) CHCl3, rt, 48 h, (2) HF 40%, 2 h, ii: CHCl3, rt, 72h.