Linear propargylic alcohol functionality attached to the indazole-7-carboxamide as a JAK1-specific linear probe group

Determination and Analysis of Thermodynamic Properties of Methyl Methylanthranilate Isomers

The enthalpies of formation in the gaseous phase of methyl 3-methylanthranilate and methyl 5-methylanthranilate were determined from experimental measurements of the corresponding standard energies of combustion, obtained from combustion calorimetry, and the standard enthalpies of vaporization and sublimation, obtained from Calvet microcalorimetry and Knudsen mass-loss effusion. A computational study, using the G3(MP2)//B3LYP composite method, has also been performed for the calculation of the gas-phase standard enthalpies of formation of those two molecules at T = 298.15 K, as well as for the remaining isomers, methyl 4-methylanthranilate and methyl 6-methylanthranilate. The results have been used to evaluate and analyze the energetic effect of the methyl substituent in different positions of the ring.

Rh(III)-Catalyzed C-H Functionalization/Annulation of 1-Arylindazolones: Divergent Synthesis of Fused Indazolones and Allyl Indazolones

Rh(III)-catalyzed C-H/N-H annulation and C-H allylation of phenylindazolones have been realized by employing 5-methylene-1,3-dioxan-2-one and 4-vinyl-1,3-dioxolan-2-one as scalable cross-coupling partners, delivering functionalized indazolone fused heterocycles and branched and linear allyl indazolones respectively in moderate to high yield. These divergent synthesis protocols showcase mild conditions, broad substrate scope, and high functional-group compatibility. In addition, scale-up synthesis and preliminary mechanistic exploratory were also accomplished.

Benzimidazole Derivatives as Potent JAK1-Selective Inhibitors

The Janus kinase (JAK) family comprises four members (JAK1, JAK2, JAK3, and Tyk2) that play a key role in mediating cytokine receptor signaling. JAK inhibition thus modulates cytokine-mediated effects. In particular, selective inhibition of JAK1 or JAK3 may provide an efficient therapeutic agent for the treatment of inflammatory diseases, with minimized side effects. In this study, as part of our continued efforts to develop a selective JAK1 inhibitor, a series of 1,2-disubstituted benzimidazole-5-carboxamide derivatives was prepared and their inhibitory activities against all four JAK isozymes were evaluated. A clear structure-activity relationship was observed with respect to JAK1 selectivity; this highlighted the importance of hydrogen bond donors at both N(1) and R2 positions located within a specific distance from the benzimidazole core. One of the synthesized compounds, 1-(2-aminoethyl)-2-(piperidin-4-yl)-1H-benzo[d]imidazole-5-carboxamide (5c), showed remarkable JAK1 selectivity (63-fold vs JAK2, 25-fold vs JAK3, and 74-fold vs Tyk2). Molecular docking revealed that the 2-aminoethyl and piperidin-4-yl substituents of 5c function as probes to differentiate the ATP-binding site of JAK1 from that of JAK2, resulting in preferential JAK1 binding. A kinase panel assay confirmed the JAK1 selectivity of 5c, which showed no appreciable inhibitory activity against 26 other protein kinases at 10 μM.

Progress toward JAK1-selective inhibitors

The discovery of the JAK-STAT pathway was a landmark in cell biology. The identification of these pathways has changed the landscape of treatment of rheumatoid arthritis and other autoimmune diseases. The two first (unselective) JAK inhibitors have recently been approved by the US FDA for the treatment of myelofibrosis and rheumatoid arthritis and many other JAK inhibitors are currently in clinical development or at the discovery stage. Research groups have demonstrated the different roles of JAK member and the therapeutic potential of targeting them selectively. JAK1 plays a critical and potentially dominant role in the transduction of γc cytokine (γc = common γ chain) and in IL-6 signaling. In this review, we will discuss the state-of-the-art research that evokes JAK1 selective inhibition.

Synthesis of acyl carbamates via four component Pd-catalyzed carbonylative coupling of aryl halides, potassium cyanate, and alcohols

A simple and mild method is demonstrated for assembling acyl carbamates through a base-free four-component Pd-catalyzed carbonylation of aryl halides in the presence of potassium cyanate and alcohols in a two-chamber system. This approach produces a wide range of aryl acyl carbamates in good to excellent yields from the corresponding aryl bromides or iodides with near-stoichiometric carbon monoxide. In addition, the method can be extended to the synthesis of primary amides thereby expanding the usefulness of cyanate as an ammonia equivalent.