Aromatic Quinolinecarboxamides as Selective, Orally Active Antibody Production Inhibitors for Prevention of Acute Xenograft Rejection
摘要:
The prevention of xenograft rejection is substantially dependent on inhibiting antibodies (Ab) produced by B-cells independently of T-cell signals (TI-1). Due to their ubiquitous biochemical mechanisms of action, the immunosuppressants currently employed not only fail to discriminate between B- and T-cells but also have a narrow therapeutic window and, thus, their prolonged use in complex immunosuppressive regimens is problematic. By capitalizing on the target enzyme-bound (DHODH) structure Ib of one of these compounds, leflunomide, and modulating part of its multiple mechanisms of action to gain selectivity, the quinoline-8-carboxamide 3 was designed as a potentially weak enzyme inhibitor but effective immunosuppressant. Compound 3 fulfilled the mechanistic criteria set and had 10-fold B-cell over T-cell selectivity. Its pyridyl analogue 4 was found to be a highly potent and selective B-cell immunosuppressant with a 75-fold selectivity for B- over T-cells las judged by the MLR data) and no general cytotoxicity at concentrations up to 160-fold higher than those required to inhibit B-cells. In the mouse, 4 effectively blocked TI-1 Ab production and suppressed Ab-mediated xenograft rejection in a xenotransplantation model under a once-daily dosing regimen, with efficacy down to 0.3 mg/kg/day po. These are the first data demonstrating the feasibility of the development of drugs specific for impeding Ah production.
Aromatic Quinolinecarboxamides as Selective, Orally Active Antibody Production Inhibitors for Prevention of Acute Xenograft Rejection
摘要:
The prevention of xenograft rejection is substantially dependent on inhibiting antibodies (Ab) produced by B-cells independently of T-cell signals (TI-1). Due to their ubiquitous biochemical mechanisms of action, the immunosuppressants currently employed not only fail to discriminate between B- and T-cells but also have a narrow therapeutic window and, thus, their prolonged use in complex immunosuppressive regimens is problematic. By capitalizing on the target enzyme-bound (DHODH) structure Ib of one of these compounds, leflunomide, and modulating part of its multiple mechanisms of action to gain selectivity, the quinoline-8-carboxamide 3 was designed as a potentially weak enzyme inhibitor but effective immunosuppressant. Compound 3 fulfilled the mechanistic criteria set and had 10-fold B-cell over T-cell selectivity. Its pyridyl analogue 4 was found to be a highly potent and selective B-cell immunosuppressant with a 75-fold selectivity for B- over T-cells las judged by the MLR data) and no general cytotoxicity at concentrations up to 160-fold higher than those required to inhibit B-cells. In the mouse, 4 effectively blocked TI-1 Ab production and suppressed Ab-mediated xenograft rejection in a xenotransplantation model under a once-daily dosing regimen, with efficacy down to 0.3 mg/kg/day po. These are the first data demonstrating the feasibility of the development of drugs specific for impeding Ah production.
Catalytic Formation of Ketones from Unactivated Esters through Rhodium Chelation-Assisted C–O Bond Activation
作者:Jingjing Wang、Sujing Zuo、Weiqiang Chen、Xinrui Zhang、Kaixin Tan、Yun Tian、Jianhui Wang
DOI:10.1021/jo400949p
日期:2013.9.6
A new method for building aryl aryl ketones containing heterocyclic rings through chelation-assisted C–O bond activation catalyzed by a rhodium complex has been developed. In this reaction, methyl quinoline-8-carboxylate, methyl quinoxaline-5-carboxylate, and their derivatives were reacted with an excess amount of a substituted phenyl boronic acid in the presence of a rhodium(I) complex to give substituted