Abstract
The 5,10-dihydro-2-thioxo-pyrimido[4,5-
b]quinolines (
2a–
c) and its oxidized form
3 were prepared and used as key intermediates for the synthesis of thiazolo[3′,2′:1,2]pyrimido[4,5-
b]-quinolines (
5a–
c), isoxazolo[5″,4″:4′,5′]thiazolo[3′,2′:1,2]pyrimido[4,5-
b]quinolines (
6a–
c), 4-chloro-2-methylthio-pyrimido[4,5-
b]quinoline, its amino derivatives (
19–
21) and 10,11,12,13-tetrahydro-5
H-quino[2′,3′:4,5]pyrimido[6,1-
b]quinazoline (
22). The newly synthesized compounds were characterized by IR, NMR (
1H,
13C) and mass spectral studies. Representative of the synthesized compounds was tested and evaluated for anti-oxidant, anti-inflammatory and analgesic activities. Compounds
2a–
c showed the highest inhibitory anti-oxidant activity either using erythrocyte hemolysis or ABTS methods. Compounds
2a,
10b,
16, and
17a manifested the best protective effect against DNA damage induced by bleomycin. Compounds
2c,
5a,
20a,
2a, and
2b exhibited a potent anti-inflammatory activity using carrageenan-induced paw edema test in rats.
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