合成路线1

The intermediate 2-(5-nitro-6-oxo-2-phenyl-1,6-dihydropyrimidin-1-yl)acetic acid (IV) has been obtained by several related ways: 1. The cyclization of N-(tert-butoxycarbonylmethyl)benzamidine (I) with 3-methoxy-2-nitro-2-propenoic acid methyl ester (II) by means of Na2CO3 gives 2-(5-nitro-6-oxo-2-phenyl-1,6-dihydropyrimidin-1-yl)acetic acid tert-butyl ester (III), which is hydrolyzed by means of TFA to the target intermediate acid (IV). 2. The direct cyclization of N-(carboxymethyl)benzamidine (V) with propenoic ester (II) by means of NaOH gives the target intermediate (IV). 3. The cyclization of N-allylbenzamidine (VI) with propenoic ester (II) by means of HCl in methanol gives the allyl pyrimidinone (VII), which is oxidized with NaIO4 and RhCl3 to afford the target intermediate acid (IV). 4. The cyclization of N-(2-furylmethyl)benzamidine (VIII) with propenoic ester (II) by means of HCl in toluene/methanol gives the furylmethyl pyrimidinone (IX), with is treated with ozone, NaIO4 and RhCl3 in acetonitrile to yield the target intermediate acid (IV). 5. The cyclization of N-(2,2-dimethoxyethyl(benzamidine (X) with propenoic ester (II) in methanol gives the pyrimidinone acetaldehyde dimethylacetal (XI), which is hydrolyzed with TFA to the corresponding aldehyde (XII). Finally, this compound is oxidized with NaClO2 to afford the target intermediate acid (IV).