الفهرس 
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Abstract
Among the most important quinazoline families, quinazoline-2,4(1H,3H)-dione de-
rivatives are considered one of the most notable pharmacophores in drug discovery
due to its broad spectrum of biological activities. It is a core scaffold for the struc-
ture of more than 200 naturally occurring alkaloids isolated from different plant
families and various microorganisms. Quinazolinedione is widely used as a func-
tional material for synthetic chemistry and drug molecules.Quinazoline-
2,4(1H,3H)-dione (1) synthesized from anthranilic acid, followed by N-alkylation
with ethyl chloroacetate in stirring dimethyl formamide in the presence of potassi-
um carbonate at room temperature. The key intermediate 2,2’-(2,4-
dioxoquinazoline-1,3(2H,4H)-diyl)di(acetohydrazide) (3) was afforded via the hy-
drazinolysis reaction of diethyl 2,2’-(2,4-dioxoquinazoline-1,3(2H,4H)-
diyl)diacetate (2) at the reflux condition. Alternatively, synthesized from 2,2’-(2,4-
dioxoquinazoline-1,3(2H,4H)- diyl)diacetonitrile (4), the hydrolysis of the respec-
tive nitrile groups to afford the acid derivative 5, was followed by esterification in
the presence of sulfuric acid and methanol. The resulting dimethyl 2,2’-(2,4-
dioxoquinazoline-1,3(2H,4H)-diyl)diacetate (6) underwent the hydrazinolysis re-
action to afford the key intermediate 3 in a good yield of 72%. The crucial deriva-
tive 7 was prepared from cyclization of dihydrazide 3 by treatment with carbon di-
sulfide in the presence of potassium hydroxide.