The acylation of diethyl L-glutamate (I) with 5-nitro-2-thienylcarbonyl chloride (II) in toluene gives N-(5-nitrothien-2-ylcarbonyl)-L-glutamic acid diethyl ester (III), which is reduced with sodium dithionite in ethanol/water to the corresponding amino compound (IV). The methylation of (IV) with methyl iodide and 2,6-lutidine yields the corresponding methylamine (V), which is condensed with 6-(bromomethyl)-2-methylquinazolin-4(3H)-one (VI) by means of 2,6-lutidine in hot DMF affording the diethyl ester (VIII) of D-1694. Finally, this compound is hydrolyzed with NaOH in ethanol/water. The bromomethyl quinazoline (VI) was obtained by selective radical bromination of 2,6-dimethylquinazolin-4(3H)-one (VII) with N-bromosuccinimide (NBS) and benzoyl peroxide in hot chloroform.

The acylation of diethyl L-glutamate (I) with 5-nitro-2-thienylcarbonyl chloride (II) in toluene gives N-(5-nitrothien-2-ylcarbonyl)-L-glutamic acid diethyl ester (III), which is reduced with sodium dithionite in ethanol/water to the corresponding amino compound (IV). The methylation of (IV) with methyl iodide and 2,6-lutidine yields the corresponding methylamine (V), which is condensed with 6-(bromomethyl)-2-methylquinazolin-4(3H)-one (VI) by means of 2,6-lutidine in hot DMF affording the diethyl ester (VIII) of D-1694. Finally, this compound is hydrolyzed with NaOH in ethanol/water. The bromomethyl quinazoline (VI) was obtained by selective radical bromination of 2,6-dimethylquinazolin-4(3H)-one (VII) with N-bromosuccinimide (NBS) and benzoyl peroxide in hot chloroform.