Meridianin derivatives as potent Dyrk1A inhibitors and neuroprotective agents
BIOORGANIC & MEDICINAL CHEMISTRY LETTERS
Authors: Yadav, Rammohan R.; Sharma, Sadhana; Joshi, Prashant; Wani, Abubakar; Vishwakarma, Ram A.; Kumar, Ajay; Bharate, Sandip B.
Abstract
Meridianins are a group of marine-derived indole alkaloids which are reported to possess kinase inhibitory activities. In the present Letter, we report synthesis of N1-substituted and C-ring modified meridianin derivatives and their evaluation as Dyrk1A inhibitors and neuroprotective agents. Among the library of 52 compounds screened, morpholinoyl linked derivative 26b and 2-nitro-4-trifluoromethyl phenyl sulfonyl derivative 29v displayed potent inhibition of Dyrk1A with IC50 values of 0.5 and 0.53 mu M, respectively. The derivative 26b also inhibited Dyrk2 and Dyrk3 with IC50 values of 1.4 and 2.2 mu M, respectively showing 2.2 and 4.4 fold selectivity for Dyrk1A with respect to Dyrk2 and Dyrk3. The compound 26b was not cytotoxic to human neuroblastoma SH-SY5Y cells (IC50 > 100 mu M) and it displayed significant neuroprotection against glutamate-induced neurotoxicity in these cells at 10 mu M. Molecular modelling studies of compound 26b led to identification of key interactions in the binding site of Dyrk1A and the possible reasons for observed Dyrk1A selectivity over Dyrk2. (C) 2015 Elsevier Ltd. All rights reserved.
Hydroxybenzothiophene Ketones Are Efficient Pre-mRNA Splicing Modulators Due to Dual Inhibition of Dyrk1A and Clk1/4
ACS MEDICINAL CHEMISTRY LETTERS
Authors: Schmitt, Christian; Miralinaghi, Parisa; Mariano, Marica; Hartmann, Rolf W.; Engel, Matthias
Abstract
Dysregulated usage of pre-mRNA splicing sites contributes to the progression of cancer, neurodegenerative diseases, and viral infections. Serine/arginine-rich (SR) proteins play major roles in the splice site recognition and are largely regulated by phosphorylation. This provides an option for the pharmacological correction of aberrant splicing by inhibiting the relevant kinases. Cdc2-like kinases (Clks) and dual specificity tyrosine phosphorylation-regulated kinases (Dyrks) were both reported to phosphorylate numerous SR proteins in vitro and in vivo. In this study, we describe the discovery of new selective dual Clk/Dyrk1A/1B inhibitors, which are able to modulate alternative pre-mRNA splicing of model gene transcripts in cells with submicromolar potencies. The optimization process yielded a dual Clk and Dyrk inhibitor with exceptionally high ligand efficiency. Our results suggested that dual inhibition of both Clk1 and Dyrk1A increased the efficacy of pre-mRNA splicing modulation.