The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Nicotinic Acid Adenine Dinucleotide Phosphate Analogues Substituted on the Nicotinic Acid and Adenine Ribosides. Effects on Receptor Mediated Ca2+ Release》. Authors are Trabbic, Christopher J.; Zhang, Fan; Walseth, Timothy F.; Slama, James T..The article about the compound:5-Hydroxynicotinic acidcas:27828-71-3,SMILESS:O=C(O)C1=CN=CC(O)=C1).COA of Formula: C6H5NO3. Through the article, more information about this compound (cas:27828-71-3) is conveyed.
Nicotinic acid adenine dinucleotide phosphate (NAADP) is a Ca2+ releasing intracellular second messenger in both mammals and echinoderms. The authors report that large functionalized substituents introduced at the nicotinic acid 5-position are recognized by the sea urchin receptor, albeit with a 20-500-fold loss in agonist potency. 5-(3-Azidopropyl)-NAADP was shown to release Ca2+ with an EC50 of 31 μM and to compete with NAADP for receptor binding with an IC50 of 56 nM. Attachment of charged groups to the nicotinic acid of NAADP is associated with loss of activity, suggesting that the nicotinate riboside moiety is recognized as a neutral zwitterion. Substituents (Br and N3) can be introduced at the 8-adenosyl position of NAADP while preserving high potency and agonist efficacy and an NAADP derivative substituted at both the 5-position of the nicotinic acid and at the 8-adenosyl position was also recognized although the agonist potency was significantly reduced.
There is still a lot of research devoted to this compound(SMILES：O=C(O)C1=CN=CC(O)=C1)COA of Formula: C6H5NO3, and with the development of science, more effects of this compound(27828-71-3) can be discovered.
Reference:
Chapter 1 An introduction to palladium catalysis,
Palladium/carbon catalyst regeneration and mechanical application method