新产品编号:2435207

Chemical Name: 3,5-Dimethyl-1H-pyrrole-2,4-dicarboxylic acid 2-tert-butyl 4-(1,2,2-trimethylpropyl) diester
项目整合开发状态: Preclinical
项目研究机构: GlaxoSmithKline (Originator)
合成路线:The known 3,5-dimethylpyrrole-2,4-dicarboxylic acid 2-benzyl ester 4-t-butyl ester (I) is subjected to benzyl group hydrogenolysis over Pd/C to provide the corresponding pyrrole-2-carboxylic acid (II).Subsequent coupling of acid (II) with 1-propanol (III) in the presence of trifluoroacetic anhydride furnishes the 2-propyl ester (IV).The 4-t-butyl ester of (IV) is then cleaved by means of trifluoroacetic acid,yielding the pyrrole-4-carboxylic acid (V).This is finally coupled to 3,3-dimethyl-2-butanol (VI) by using trifluoroacetic anhydride to furnish the target pyrrole diester.

合成路线:Nitrosation of tert-butyl acetoacetate (I) with NaNO2 in cold AcOH leads to oxime (II),which is further condensed with benzyl acetoacetate (III) in the presence of Zn and ammonium acetate,to produce pyrrole (IV).The 4-benzyl ester of (IV) is selectively removed by catalytic hydrogenolysis over Pd/C,yielding the pyrrole-4-carboxylic acid (V).Subsequent coupling of acid (V) with 3,3-dimethyl-2-butanol (VI) employing trifluoroacetic anhydride furnishes the target pyrrole diester.