合成路线1

2. The reaction of the diacid monoester (IV) with oxalyl chloride in benzene gives the corresponding acyl chloride (V), which is treated with aniline (II) and pyridine in THF, yielding the monoester monoamide (VI). The hydrolysis of the ester group of (VI) with OH in refluxing methanol affords the monoamide carboxylic acid (VII), which is condensed with O-benzylhydroxylamine (VIII) by means of DCC in pyridine to provide the protected hydroxamic acid (IX). Finally, this compound is debenzylated with H2 over Pd/C in methanol to furnish the target hydroxamic acid with yields of 35-65%. 3. A mixture of diacid dichloride (I), aniline (II) and O-benzylhydroxylamine (VIII) in pyridine gives, after chromatographic purification, the protected hydroxamic acid (IX), which is debenzylated as before to provide the target hydroxamic acid with yields of 20-35%. 4. The reaction of acid dichloride (I) with aniline (II) and O-(trimethylsilyl)hydroxylamine (X) by means of TEA in chloroform gives the trimethylsilyl protected compound (XI), which is desilylated with NH4Cl in hot methanol to afford the target hydroxamic acid with yields of 20-33%.