Title compound was prepared by condensation of tetrahydroindolizinone (I) with pyridine-4-carboxyaldehyde (II) under phase transfer conditions using NaOH and tetrabutyl hydrogensulfate in a mixture of H2O and CH2Cl2.
The cyclization of the amino group of 4-amino-3-(4-chlorophenyl)butyric acid (I) with 2,5-dimethoxytetrahydrofuran (II) by means of AcOH in THF gives the corresponding pyrrole (III), which is cyclized by means of TEA, ClCOOEt, pyrrolidine and POCl3 in toluene yielding the pyrrolopyridone (IV). Finally, this compound is condensed with pyridine-4-carbaldehyde (V) by means of tetrabutylammonium bisulfate and NaOH in water.
The cyclization of the amino group of 4-amino-3-(4-chlorophenyl)butyric acid (I) with 2,5-dimethoxytetrahydrofuran (II) by means of AcOH in THF gives the corresponding pyrrole (III), which is cyclized by means of TEA, ClCOOEt, pyrrolidine and POCl3 in toluene yielding the pyrrolopyridone (IV). Finally, this compound is condensed with pyridine-3-carbaldehyde (V) by means of tetrabutylammonium bisulfate and NaOH in water.