RESUMEN
In an effort to improve the pharmacokinetic and pharmacodynamic properties of the cognition-enhancer linopirdine (DuP 996), a number of core structure analogues were prepared in which the 4-pyridyl pendant group was systematically replaced with 2-fluoro-4-pyridyl. This strategy resulted in the discovery of several compounds with improved activity in acetylcholine (ACh) release-enhancing assays, in vitro and in vivo. The most effective compound resulting from these studies, 10, 10-bis[(2-fluoro-4-pyridinyl)methyl]-9(10H)-anthracenone (9), is between 10 and 20 times more potent than linopirdine in increasing extracellular hippocampal ACh levels in the rat with a minimum effective dose of 1 mg/kg. In addition to superior potency, 9 possesses an improved pharmacokinetic profile compared to that of linopirdine. The half-life of 9 (2 h) in rats is 4-fold greater than that of linopirdine (0.5 h), and it showed a 6-fold improvement in brain-plasma distribution over linopirdine. On the basis of its pharmacologic, pharmacokinetic, absorption, and distribution properties, 9 (DMP543) has been advanced for clinical evaluation as a potential palliative therapeutic for treatment of Alzheimer's disease.
Asunto(s)
Acetilcolina/metabolismo , Antracenos/síntesis química , Indoles , Nootrópicos , Piridinas , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Antracenos/química , Antracenos/farmacocinética , Antracenos/farmacología , Evaluación Preclínica de Medicamentos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Técnicas In Vitro , Indoles/química , Indoles/farmacocinética , Indoles/farmacología , Masculino , Microdiálisis , Nootrópicos/síntesis química , Nootrópicos/química , Nootrópicos/farmacocinética , Nootrópicos/farmacología , Piridinas/química , Piridinas/farmacocinética , Piridinas/farmacología , Ratas , Relación Estructura-ActividadRESUMEN
To search for TNF-alpha (tumor necrosis factor alpha) converting enzyme (TACE) inhibitors, we designed a new class of macrocyclic hydroxamic acids by linking the P1 and P2' residues of acyclic anti-succinate-based hydroxamic acids. A variety of residues including amide, carbamate, alkyl, sulfonamido, Boc-amino, and amino were found to be suitable P1-P2' linkers. With an N-methylamide at P3', the 13-16-membered macrocycles prepared exhibited low micromolar activities in the inhibition of TNF-alpha release from LPS-stimulated human whole blood. Further elaboration in the P3'-P4' area using the cyclophane and cyclic carbamate templates led to the identification of a number of potent analogues with IC(50) values of =0.2 microM in whole blood assay (WBA). Although the P3' area can accommodate a broad array of structurally diversified functional groups including polar residues, hydrophobic residues, and amino and carboxylic acid moieties, in both the cyclophane series and the cyclic carbamate series, a glycine residue at P3' was identified as a critical structural component to achieve both good in vitro potency and good oral activity. With a glycine residue at P3', an N-methylamide at P4' provided the best cyclophane analogue, SL422 (WBA IC(50) = 0.22 microM, LPS-mouse ED(50) = 15 mg/kg, po), whereas a morpholinylamide at P4' afforded the most potent and most orally active cyclic carbamate analogue, SP057 (WBA IC(50) = 0.067 microM, LPS-mouse ED(50) = 2.3 mg/kg, po). Further profiling for SL422 and SP057 showed that these macrocyclic compounds are potent TACE inhibitors, with K(i) values of 12 and 4.2 nM in the porcine TACE assay, and are broad-spectrum MMP inhibitors. Pharmacokinetic studies in beagle dogs revealed that SL422 and SP057 are orally bioavailable, with oral bioavailabilities of 11% and 23%, respectively.
Asunto(s)
Inhibidores Enzimáticos/síntesis química , Ácidos Hidroxámicos/síntesis química , Lactamas/síntesis química , Metaloendopeptidasas/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Proteínas ADAM , Proteína ADAM17 , Administración Oral , Animales , Disponibilidad Biológica , Carbamatos/síntesis química , Carbamatos/química , Carbamatos/farmacocinética , Carbamatos/farmacología , Perros , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Humanos , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacocinética , Ácidos Hidroxámicos/farmacología , Técnicas In Vitro , Lactamas/química , Lactamas/farmacocinética , Lactamas/farmacología , Masculino , Ratones , Estereoisomerismo , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/análisisRESUMEN
In search of antiinflammatory drugs with a new mechanism of action, U0126 was found to functionally antagonize AP-1 transcriptional activity via noncompetitive inhibition of the dual specificity kinase MEK with an IC50 of 0.07 microM for MEK 1 and 0.06 microM for MEK 2. U0126 can undergo isomerization and cyclization reactions to form a variety of products, both chemically and in vivo, all of which exhibit less affinity for MEK and lower inhibition of AP-1 activity than parent, U0126.