74788-44-6Relevant articles and documents
Pharmacological characterization of a new series of carbamoylguanidines reveals potent agonism at the H2R and D3R
Biselli, Sabrina,Bresinsky, Merlin,Buschauer, Armin,Forster, Lisa,Honisch, Claudia,Pockes, Steffen,Tropmann, Katharina,Bernhardt, Günther
supporting information, (2021/02/12)
Even today, the role of the histamine H2 receptor (H2R) in the central nervous system (CNS) is widely unknown. In previous research, many dimeric, high-affinity and subtype-selective carbamoylguanidine-type ligands such as UR-NK22 (5, pKi = 8.07) were reported as H2R agonists. However, their applicability to the study of the H2R in the CNS is compromised by their molecular and pharmacokinetic properties, such as high molecular weight and, consequently, a limited bioavailability. To address the need for more drug-like H2R agonists with high affinity, we synthesized a series of monomeric (thio)carbamoylguanidine-type ligands containing various spacers and side-chain moieties. This structural simplification resulted in potent (partial) agonists (guinea pig right atrium, [35S]GTPγS and β-arrestin2 recruitment assays) with human (h) H2R affinities in the one-digit nanomolar range (pKi (139, UR-KAT523): 8.35; pKi (157, UR-MB-69): 8.69). Most of the compounds presented here exhibited an excellent selectivity profile towards the hH2R, e.g. 157 being at least 3800-fold selective within the histamine receptor family. The structural similarities of our monomeric ligands to pramipexole (6), a dopamine receptor agonist, suggested an investigation of the binding behavior at those receptors. The target compounds were (partial) agonists with moderate affinity at the hD2longR and agonists with high affinity at the hD3R (e.g. pKi (139, UR-KAT523): 7.80; pKi (157, UR-MB-69): 8.06). In summary, we developed a series of novel, more drug-like H2R and D3R agonists for the application in recombinant systems in which either the H2R or the D3R is solely expressed. Furthermore, our ligands are promising lead compounds in the development of selective H2R agonists for future in vivo studies or experiments utilizing primary tissue to unravel the role and function of the H2R in the CNS.
Rh(III)-catalyzed synthesis of isoquinolines using the N-Cl bond of N-chloroimines as an internal oxidant
Chu, Benfa,Fang, Lili,Guo, Shan,Qi, Bing,Shi, Pengfei,Wang, Qi,Zhu, Jin
supporting information, (2020/03/10)
The Rh(III)-catalyzed coupling of N-chloroimines with alkynes for the efficient synthesis of isoquinolines is reported. This represents the first use of the N-Cl bond of N-chloroimines as an internal oxidant for construction of the isoquinoline skeleton. The synthesis features atom and step economy, a green solvent (EtOH), mild reaction conditions, and a broad substrate scope.
Carbon Dioxide-Mediated C(sp2)-H Arylation of Primary and Secondary Benzylamines
Kapoor, Mohit,Chand-Thakuri, Pratibha,Young, Michael C.
supporting information, p. 7980 - 7989 (2019/05/22)
C-C bond formation by transition metal-catalyzed C-H activation has become an important strategy to fabricate new bonds in a rapid fashion. Despite the pharmacological importance of ortho-arylbenzylamines, however, effective ortho-C-C bond formation of free primary and secondary benzylamines using PdII remains an outstanding challenge. Presented herein is a new strategy for constructing ortho-arylated primary and secondary benzylamines mediated by carbon dioxide (CO2). The use of CO2 with Pd is critical to allowing this transformation to proceed under relatively mild conditions, and mechanistic studies indicate that it (CO2) is directly involved in the rate-determining step. Furthermore, the milder temperatures furnish free amine products that can be directly used or elaborated without the need for deprotection. In cases where diarylation is possible, an interesting chelate effect is shown to facilitate selective monoarylation.