Search

Abstract: A novel class of pyrazolopyridazine p38α mitogen-activated protein kinase (MAPK) inhibitors is disclosed. A structure activity relationship (SAR) investigation was conducted driven by the ability of these compounds to inhibit the p38α enzyme, the secretion of TNFα in a LPS-challenged THP1 cell line and TNFα-induced production of IL-8 in the presence of 50% human whole blood (hWB). This study resulted in the discovery of several inhibitors with IC50 values in the single-digit nanomolar range in hWB. Further investigation of the pharmacokinetic profiles of these lead compounds led to the identification of three potent and orally bioavailable p38α inhibitors 2h, 2m, and 13h. Inhibitor 2m was found to be highly selective for p38α/β over a panel of 402 other kinases in Ambit screening, and was highly efficacious in vivo in the inhibition of TNFα production in LPS-stimulated Lewis rats with an ED50 of ca. 0.08mg/kg. [Copyright &y& Elsevier]

Abstract: A novel class of fused pyrazole-derived inhibitors of p38α mitogen-activated protein kinase (MAPK) is disclosed. These inhibitors were evaluated for their ability to inhibit the p38α enzyme, the secretion of TNFα in a LPS-challenged THP1 cell line and TNFα-induced production of IL-8 in 50% human whole blood. This series was optimized through a SAR investigation to provide inhibitors with IC50 values in the low single-digit nanomolar range in whole blood. Further investigation of their pharmacokinetic profiles led to the identification of two potent and orally bioavailable p38 inhibitors 10m and 10q. Inhibitor 10m was found to be efficacious in vivo in the inhibition of TNFα production in LPS-stimulated Lewis rats with an ED50 of 0.1mg/kg while 10q was found to have an ED50 of 0.05–0.07mg/kg. [Copyright &y& Elsevier]

Abstract: Phosphoinositide 3-kinase (PI3K) is an important target in oncology due to the deregulation of the PI3K/Akt signaling pathway in a wide variety of tumors. A series of 4-amino-6-methyl-1,3,5-triazine sulfonamides were synthesized and evaluated as inhibitors of PI3K. The synthesis, in vitro biological activities, pharmacokinetic and in vivo pharmacodynamic profiling of these compounds are described. The most promising compound from this investigation (compound 3j) was found to be a pan class I PI3K inhibitor with a moderate (>10-fold) selectivity over the mammalian target of rapamycin (mTOR) in the enzyme assay. In a U87 MG cellular assay measuring phosphorylation of Akt, compound 3j displayed low double digit nanomolar IC50 and exhibited good oral bioavailability in rats (F oral =63%). Compound 3j also showed a dose dependent reduction in the phosphorylation of Akt in a U87 tumor pharmacodynamic model with a plasma EC50 =193nM (91ng/mL). [Copyright &y& Elsevier]

A highly selective series of inhibitors of the classI phosphatidylinositol3-kinases (PI3Ks) has been designed and synthesized. Starting fromthe dual PI3K/mTOR inhibitor 5, a structure-based approachwas used to improve potency and selectivity, resulting in the identificationof 54as a potent inhibitor of the class I PI3Ks withexcellent selectivity over mTOR, related phosphatidylinositol kinases,and a broad panel of protein kinases. Compound 54demonstrateda robust PD–PK relationship inhibiting the PI3K/Akt pathwayin vivo in a mouse model, and it potently inhibited tumor growth ina U-87 MG xenograft model with an activated PI3K/Akt pathway. [ABSTRACT FROM AUTHOR]

Abstract: Structure–activity relationship (SAR) investigations of a novel class of triazolopyridazinone p38α mitogen activated protein kinase (MAPK) inhibitors are disclosed. From these studies, increased in vitro potency was observed for 2,6-disubstituted phenyl moieties and N-ethyl triazolopyridazinone cores due to key contacts with Leu108, Ala157 and Val38. Further investigation led to the identification of three compounds, 3g, 3j and 3m that are highly potent inhibitors of LPS-induced MAPKAP kinase 2 (MK2) phosphorylation in 50% human whole blood (hWB), and possess desirable in vivo pharmacokinetic and kinase selectivity profiles. [Copyright &y& Elsevier]