The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Kynurenic acid may underlie sex-specific immune responses to COVID-19》. Authors are Cai, Yuping; Kim, Daniel J.; Takahashi, Takehiro; Broadhurst, David I.; Yan, Hong; Ma, Shuangge; Rattray, Nicholas J. W.; Casanovas-Massana, Arnau; Israelow, Benjamin; Klein, Jon; Lucas, Carolina; Mao, Tianyang; Moore, Adam J.; Muenker, M. Catherine; Oh, Ji Eun; Silva, Julio; Wong, Patrick; Ko, Albert I.; Khan, Sajid A.; Iwasaki, Akiko; Johnson, Caroline H..The article about the compound:4-Hydroxyquinoline-2-carboxylic Acidcas:492-27-3,SMILESS:O=C(C1=NC2=CC=CC=C2C(O)=C1)O).HPLC of Formula: 492-27-3. Through the article, more information about this compound (cas:492-27-3) is conveyed.
Coronavirus disease 2019 (COVID-19) has poorer clin. outcomes in males than in females, and immune responses underlie these sex-related differences. Because immune responses are, in part, regulated by metabolites, we examined the serum metabolomes of COVID-19 patients. In male patients, kynurenic acid (KA) and a high KAtokynurenine (K) ratio (KA:K) pos. correlated with age and with inflammatory cytokines and chemokines and neg. correlated with T cell responses. Males that clin. deteriorated had a higher KA:K than those that stabilized. KA inhibits glutamate release, and glutamate abundance was lower in patients that clin. deteriorated and correlated with immune responses. Anal. of data from the Genotype-Tissue Expression (GTEx) project revealed that the expression of the gene encoding the enzyme that produces KA, kynurenine aminotransferase, correlated with cytokine abundance and activation of immune responses in older males. This study reveals that KA has a sex-specific link to immune responses and clin. outcomes in COVID-19, suggesting a pos. feedback between metabolites and immune responses in males.
Different reactions of this compound(4-Hydroxyquinoline-2-carboxylic Acid)HPLC of Formula: 492-27-3 require different conditions, so the reaction conditions are very important.
Reference:
Copper catalysis in organic synthesis – NCBI,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”