Synthesis of Pyrrolo[3,4-<i>b</i>]pyridin-5-ones via Multicomponent Reactions and In Vitro–In Silico Studies Against SiHa, HeLa, and CaSki Human Cervical Carcinoma Cell Lines

Abstract

A series of 12 polysubstituted pyrrolo[3,4-b]pyridin-5-ones were synthesized via a one-pot cascade process (Ugi−3CR/aza Diels-Alder/N-acylation/decarboxylation/dehydration) and studied in vitro using human epithelial cervical carcinoma SiHa, HeLa, and CaSki cell line cultures. Three compounds of the series exhibited significative cytotoxicity against the three cell lines, with HeLa being the most sensitive one. Then, based on these results, in silico studies by docking techniques were performed using Paclitaxel as a reference and αβ-tubulin as the selected biological target. Worth highlighting is that strong hydrophobic interactions were observed between the three active molecules and the reference drug Paclitaxel, to the αβ-tubulin. In consequence, it was determined that hydrophobic−aromatic moieties of bioactive compounds and Paclitaxel play a key role in making stronger interactions to the ligand−target complex. A quantitative structure activity relationship (QSAR) study revealed that the six membered rings are the most significant molecular frameworks, being present in all proposed models for the in vitro-studied cell lines. Finally, also from the docking interpretation, a ligand-based pharmacophore model is proposed in order to find further potential polyheterocyclic candidates to bind stronger to the αβ-tubulin.

Keywords

• pyrrolo[3,4-<i>b</i>]pyridin-5-ones
• paclitaxel
• αβ-tubulin
• cervical cancer
• SiHa
• HeLa
• Caski
• molecular docking
• QSAR
• pharmacophore model