19519-01-8Relevant articles and documents
Engineered Substrate for Cyclooxygenase-2: A Pentapeptide Isoconformational to Arachidonic Acid for Managing Inflammation
Kaur, Baljit,Kaur, Manpreet,Kaur, Navjot,Garg, Saweta,Bhatti, Rajbir,Singh, Palwinder
, p. 6363 - 6376 (2019/07/08)
Beyond the conventional mode of working of anti-inflammatory agents through enzyme inhibition, herein, COX-2 was provided with an alternate substrate. A proline-centered pentapeptide isoconformational to arachidonic acid, which exhibited appreciable selectivity for COX-2, overcoming acetic acid- and formalin-induced pain in rats to almost 80%, was treated as a substrate by the enzyme. Remarkably, COX-2 metabolized the pentapeptide into small fragments consisting mainly of di- and tripeptides that ensured the safe breakdown of the peptide under in vivo conditions. The kinetic parameter Kcat/Km for COX-2-mediated metabolism of the peptide (6.3 × 105 M-1 s-1) was quite similar to 9.5 × 105 M-1 s-1 for arachidonic acid. Evidenced by the molecular dynamic studies and the use of Y385F COX-2, it was observed that the breakage of the pentapeptide has probably been taken place through H-bond activation of the peptide bond by the side chains of Y385 and S530.
Recyclable hypervalent iodine(III) reagent iodosodilactone as an efficient coupling reagent for direct esterification, amidation, and peptide coupling
Tian, Jun,Gao, Wen-Chao,Zhou, Dong-Mei,Zhang, Chi
supporting information; experimental part, p. 3020 - 3023 (2012/08/07)
A hypervalent iodine(III) reagent plays a novel role as an efficient coupling reagent to promote the direct condensation between carboxylic acids and alcohols or amines to provide esters, macrocyclic lactones, amides, as well as peptides without racemization. The regeneration of iodosodilactone (1) can also be readily achieved. The intermediate acyloxyphosphonium ion C from the activation of a carboxylic acid is thought to be involved in the present esterification reaction.