RESUMEN
Small molecules that modulate the 14-3-3 protein-protein interaction (PPI) network represent valuable therapeutics and tool compounds. However, access has been lost to 14-3-3 PPI molecular glues of the cotylenin class, leading to investigations into the practical chemical syntheses of congeners and analogues. Here we report a concise synthesis of (-)-cotylenol via a 10-step asymmetric entry into a diversifiable 5-8-5 core. This route features a mild Liebeskind-Srogl fragment coupling that tolerates unprecedented steric hindrance to produce a highly congested ketone, and a tandem Claisen-ene cascade that establishes the 8-membered ring. Late-stage control of stereochemistry and functionality leads to (-)-cotylenol and sets the stage for focused library synthesis.
Asunto(s)
Diterpenos , Proteínas 14-3-3 , Biblioteca de Genes , CetonasRESUMEN
The selective and efficient removal of oxygenated groups from lignin-derived phenols is a critical challenge to utilize lignin as a source for renewable aromatic chemicals. This report describes how surface modification of a zeolite-supported Pt catalyst using ionic liquids (ILs) remarkably increases selectivity for the hydrodeoxygenation (HDO) of phenols into arenes under mild reaction conditions using atmospheric pressure H2 . Unmodified Pt/H-ZSM-5 converts phenols into aliphatic species as the major products along with a slight amount of arenes (10 % selectivity). In contrast, the catalyst modified with an IL, 1-butyl-3-methylimidazolium triflate, keeps up to 76 % selectivity for arenes even at a nearly complete conversion of phenols. The IL on the surface of Pt catalyst may offer the adsorption of phenols in an edge-to-face manner onto the surface, thus accelerating the HDO without the ring hydrogenation.
RESUMEN
We previously reported that 2,5-dimethylcelecoxib (DM-celecoxib), a celecoxib derivative that is unable to inhibit cyclooxygenase-2, prevented cardiac remodeling by activating glycogen synthase kinase-3 (GSK-3) and prolonged the lifespan of heart failure mice with genetic dilated cardiomyopathy or transverse aortic constriction-induced left ventricular hypertrophy. However, it remained unclear how DM-celecoxib regulated structure and function of cardiomyocytes and cardiac fibroblasts involved in cardiac remodeling. In the present study, therefore, we investigated the effect of DM-celecoxib on isoprenaline-induced cardiomyocyte hypertrophy and cardiac fibroblast activation, because DM-celecoxib prevented isoprenaline-induced cardiac remodeling in vivo. DM-celecoxib suppressed isoprenaline-induced neonatal rat cardiomyocyte hypertrophy by the inhibition of Akt phosphorylation resulting in the activation of GSK-3 and the inhibition of ß-catenin and mammalian target of rapamycin (mTOR). DM-celecoxib also suppressed the proliferation and the production of matrix metalloproteinase-2 and fibronectin of rat cardiac fibroblasts. Moreover, we found that phosphatase and tensin homolog on chromosome 10 (PTEN) could be a molecule to mediate the effect of DM-celecoxib on Akt. These results suggest that DM-celecoxib directly improves the structure and function of cardiomyocytes and cardiac fibroblasts and that this compound could be clinically useful for the treatment of ß-adrenergic receptor-mediated maladaptive cardiac remodeling.