Cinchonine

Cinchonine, an alkaloid found in the bark of various Cinchona species, possesses notable pharmacological properties, including anti‐microbial, anti‐parasitic, anti‐inflammatory, and anti‐obesity effects. Recent research highlights its potential anticancer properties, particularly against leukemia (K562) cells, as its molecular mechanisms remain underexplored. This study assessed cinchonine's antiproliferative effects on K562 cells using NRU, SRB, and MTT assays. It was further investigated for its interactions with molecular targets such as DHFR, COX‐2, 5‐LOX, HYAL, CATD, and ODC through cell‐free and cell‐based systems, docking studies, and qRT‐PCR analysis. Cinchonine inhibited K562 cells growth with an IC 50 of 46.55 µM (NRU assay) and significantly suppressed COX‐2 activity (IC 50 44.65 µM) and expression. It induced G0/G1 cell cycle arrest and increased the sub‐diploid population in K562 cells. In vivo, cinchonine reduced tumor growth in EAC and S‐180 models by 48.49% and 37.86%, respectively, at 50 mg/kg body weight. Toxicity predictions and ex vivo tests confirmed its safety profile. These findings suggest cinchonine as a promising chemopreventive agent for leukemia.

A metal‐free, biocompatible catalyst for the cycloaddition of CO 2 to N ‐alkyl aziridines was easily obtained by protonating the natural and nontoxic alkaloid (+)‐cinchonine. This bifunctional catalytic system promoted the synthesis of the desired products under very mild experimental conditions (room temperature and atmospheric CO 2 pressure) and without the aid of any cocatalyst. No specific equipment is required, making the procedure practical for application in any laboratory. The high synthetic value of this methodology can be attributed to the combination of excellent regioselectivity in oxazolidinone synthesis and the remarkable chemical stability of the catalyst, which can be recycled and reused for at least three consecutive cycles without any significant loss of activity.