In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called Synthesis of copper and zinc 2-(pyridin-2-yl)imidazo[1,2-a]pyridine complexes and their potential anticancer activity, published in 2017-01-27, which mentions a compound: 31181-89-2, Name is 5-Chloropicolinaldehyde, Molecular C6H4ClNO, Name: 5-Chloropicolinaldehyde.
A small library of novel copper and zinc imidazo[1,2-a]pyridine complexes were synthesized. Their structures were confirmed by x-ray diffraction crystallog. and a selection of these compounds was tested against five cancer cell lines originating from breast cancer (MCF-7 and MDA-MB-231), leukemia (K562 and HL-60) and colorectal cancer (HT-29). The imidazo[1,2-a]pyridines and their zinc complexes showed poor anticancer activity, while the copper complexes were active against the cancer cell lines with IC50 values comparable to and lower than camptothecin. For example, copper 6-bromo-N-cyclohexyl-2-(pyridin-2-yl)imidazo[1,2-a]pyridin-3-amine acetate 21 had an IC50 value <1 μM against the HT-29 cells. Fluorescence microscopy with acridine orange, Hoechst 33342 and ethidium bromide, used in a preliminary study to evaluate morphol. changes showed that copper 6-bromo-N-cyclohexyl-2-(pyridin-2-yl)imidazo[1,2-a]pyridin-3-amine acetate 21 caused both apoptosis, necrosis and para-ptosis in the MCF-7 and HL-60 cells. A select group of copper N-cyclohexyl-2-(pyridin-2-yl)imidazo[1,2-a]pyridin-3-amines (26, 27, 29 and 31) induced apoptosis, para-ptosis and deformed nuclei in MCF-7 cells. In addition to the literature in the link below, there is a lot of literature about this compound(5-Chloropicolinaldehyde)Name: 5-Chloropicolinaldehyde, illustrating the importance and wide applicability of this compound(31181-89-2).
Reference:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate