Regio- and diastereoselective synthesis of new functionalized indolo[2,3-b]indole-pyrimidine based on C–N bond formation via a four-component reaction.

A facile and diastereoselective synthetic procedure has been designed for the preparation of new substituted indolo[2,3- b ]indole (IDID) moiety at position-5 of the pyrimidine ring by a one-pot four-component reaction of dimedone, aniline and substituted derivatives, barbituric acid/thiobarbituric acid and isatin under mild conditions. This method proceeds rely on a CsbndN bond formation under catalyst-free conditions affording a range of skeletally diversity 5-indolo[3,2- b ]indole-pyrimidine-based heterocycles. 5-Indolo[2,3- b ]indol-pyrimidine-2,4,6-trione and 5-indolo[2,3- b ]indol-2-thioxo-pyrimidine-4,6-dione were obtained in EtOH solvent in high yield, short reaction time and diastereoselectivity. The structural diversities of the synthesized compounds have been confirmed spectroscopically, by IR 1 H- and 13 C NMR, EI-MS spectra and elemental analyses which agree with the proposed structures. [ABSTRACT FROM AUTHOR]