Highly Efficient One‐Pot Synthesis and Molecular Docking Studies of Pyrimido[4,5‐ <i>b</i> ]Quinoline and Pyrido[2,3‐ <i>d</i> ]Pyrimidine Derivatives as Potential <i>α</i> ‐Amylase Inhibitors

ABSTRACT The advancement in environmentally sustainable synthetic methodologies for the bioactive heterocycles has become a central focus in modern organic chemistry. In this work, we have disclosed an efficient, cost‐effective, and environmentally benign protocol for the synthesis of pyrimido[4,5‐ b ]quinoline and pyrido[2,3‐ d ]pyrimidine scaffolds involving cyclic 1,3‐dicarbonyls, aryl aldehydes, and 6‐aminouracil. Using L‐proline taurinate (LPT) as a homogeneous ionic catalyst, this method facilitates the efficient synthesis of target compounds in excellent yields. The broad substrate scope was validated through reactions involving various aryl/heterocyclic aldehydes and 1,3‐dicarbonyls such as 1,3‐cyclohexanedione, dimedone, 5‐methyl‐1,3‐cyclohexanedione, and Meldrum's acid. Fourteen derivatives, including 12 new compounds, were obtained using this method in excellent yields (88%–97%) within 10–25 min. The synthesized derivatives were well confirmed through spectral studies. The plus points of this approach include the use of an environmentally benign catalyst, straightforward product isolation, gram‐scale synthesis, and recyclability for up to five cycles. In addition, all the synthesized derivatives were docked into the active site of the α ‐amylase protein (PDB ID: 5E0F) to evaluate their potential as antidiabetic agents and observed the binding energy between −8.18 and −9.78 kcal/mol.