TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The process further comprises: either reacting 17.8 g of 2-cyano-4,5-dimethoxy-phenyl-ammonium, 20 g of dimethoxymethyl-dimethyl-amine and 10 ml of toluene in 50 ml of one-neck round flask to obtain a reaction mixture and then heating at 50 degrees C for 3 hours, removing and separating excess dimethoxymethyl-dimethyl-amine and solvent to obtain residue, purifying the residue and then drying to obtain N'-(2-cyano-4,5-dimethoxy-phenyl)-N,N-dimethyl-formamidine as intermediate, reacting the intermediate with 7.03 g of amino-acetic acid ethyl ester to obtain a reaction mixture and then stirring at 80 degrees C for 2 hours to obtain 8,9-dimethoxy-2H-imidazo(1,2-c)quinazolin-3-one; or reacting 30.5 g of 2-cyano-4,5-dimethoxy-phenyl-ammonium, 60 g of dimethoxymethyl-dimethyl-amine, 100 ml of ethyl acetate and 10 ml L-acetic acid in 250 ml of one-neck round flask to obtain a reaction mixture and then heating at 50 degrees C for 2 hours, removing and separating excess dimethoxymethyl-dimethyl-amine and solvent to obtain a residue, purifying the residue and then drying to obtain N'-(2-cyano-4,5-dimethoxy-phenyl)-N,N-dimethyl-formamidine as intermediate, reacting the intermediate with 11.03 g of amino-acetic acid ethyl ester to obtain the reaction mixture and then stirring at 80 degrees C for 2 hours to obtain 8,9-dimethoxy-2H-imidazo(1,2-c)quinazolin-3-one. (I) and (II) are reacted in the presence or absence of a solvent-A at 0-180 degrees C for 1-48 hours. (III) is reacted with (IV) in the presence of a solvent-B at 0-160 degrees C for 1-48 hours. The purification step is carried out by extraction, recrystallization or column chromatography method. Preferred Components: (III) is in cis and trans isomeric form. The solvent-A includes dichloromethane, 1 2-dichloroethane, chloroform, tetrahydrofuran, ethyl acetate, acetonitrile, toluene, xylene or diethyl ether. The solvent-B includes methylene, chloroform, tetrahydrofuran, ethyl acetate, acetonitrile, acetic acid, trifluoroacetic acid, propionic acid, iso-propionic acid or butyric acid. The molar ratio of (I), (II) and the solvent-A is 1:1-50:0-200. The molar ratio of (III), (IV) and the solvent-B is 1:1-20:1-60.