Reid, Robert C. et al. published their research in Journal of Medicinal Chemistry in 2014 | CAS: 200115-86-2

Potent Heterocyclic Ligands for Human Complement C3a Receptor was written by Reid, Robert C.;Yau, Mei-Kwan;Singh, Ranee;Hamidon, Johan K.;Lim, Junxian;Stoermer, Martin J.;Fairlie, David P.. And the article was included in Journal of Medicinal Chemistry in 2014.Category: benzofurans This article mentions the following:

The G-protein coupled receptor (C3aR) for human inflammatory protein complement C3a is an important component of immune, inflammatory, and metabolic diseases. A flexible compound (N2-[(2,2-diphenylethoxy)acetyl]-L-arginine, designated compound 4) known as a weak C3aR antagonist (IC₅₀ μM), was transformed here into potent agonists (EC₅₀ nM) of human macrophages (Ca²⁺ release in HMDM) by incorporating aromatic heterocycles. Antagonists were also identified. A linear correlation between binding affinity for C3aR and calculated hydrogen-bond interaction energy of the heteroatom indicated that its hydrogen-bonding capacity influenced ligand affinity and function mediated by C3aR. Hydrogen-bond accepting heterocycles (e.g., imidazole) conferred the highest affinity and agonist potency (e.g., 21, EC₅₀ 24 nM, Ca²⁺, HMDM) with comparable efficacy and immunostimulatory activity as that of C3a in activating human macrophages (Ca²⁺, IL1β, TNFα, CCL3). These potent and selective modulators of C3aR, inactivated by a C3aR antagonist, are stable C3a surrogates for interrogating roles for C3aR in physiol. and disease. In the experiment, the researchers used many compounds, for example, H-Arg(Pbf)-OH (cas: 200115-86-2Category: benzofurans).

H-Arg(Pbf)-OH (cas: 200115-86-2) belongs to benzofurans derivatives. Benzofuran derivatives are one of the most important oxygen-containing heterocycles. Benzofurans are stable towards alkali and readily polymerize on treatment with sulfuric acid, due to which they are useful for the preparation of low cost chemically relatively inert resins.Category: benzofurans

Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem