Search

Herein, we report the discovery of a series of JAK1-selective kinase inhibitors with high potency and excellent JAK family subtype selectivity. A fragment screening hit 1 with a pyrazolopyridone core and a JAK1 bias was selected as the starting point for our fragment-based lead generation efforts. A two-stage strategy was chosen with the dual aims of improving potency and JAK1 selectivity: Optimization of the lipophilic ribose pocket-targeting substituent was followed by the introduction of a variety of P-loop-targeting functional groups. Combining the best moieties from both stages of the optimization afforded compound 40, which showed excellent potency and selectivity. Metabolism studies in vitro and in vivo together with an in vitro safety evaluation suggest that 40 may be a viable lead compound for the development of highly subtype-selective JAK1 inhibitors.

A three-step continuous-flow synthesis system and its application to the assembly of a new series of chemo- kine receptor ligands directly from commercial building blocks is reported. No scavenger columns or solvent switches are necessary to recover the desired test compounds, which were obtained in overall yields of 49-94 %. The system is modular and flexible, and the individual steps of the se- quence can be interchanged with simi- lar outcome, extending the scope of the chemistry. Biological evaluation con- firmed activity on the chemokine CCR8 receptor and provided initial structure-activity-relationship (SAR) information for this new ligand series, with the most potent member display- ing full agonist activity with single-digit nanomolar potency. To the best of our knowledge, this represents the first published example of efficient use of multistep flow synthesis combined with biological testing and SAR studies in medicinal chemistry.

Novel triazoloquinazolines have been found as phosphodiesterase 10A (PDE10A) inhibitors. Structure–activity studies improved the initial micromolar potency which was found in the lead compound by a 100-fold identifying 5-(1H-benzoimidazol-2-ylmethylsulfanyl)-2-methyl-[1,2,4]triazolo[1,5-c]quinazoline, 42 (PDE10A IC50 = 12 nM) as the most potent compound from the series. Two X-ray structures revealed novel binding modes to the catalytic site of the PDE10A enzyme.

A series of metabotropic glutamate 5 receptor (mGluR5) allosteric ligands with positive, negative or no modulatory efficacy is described. The ability of this series to yield both mGluR5 PAMs and NAMs with single-digit nanomolar potency is unusual, and the underlying SAR is detailed.

This Letter describes the discovery of a novel series of mGluR5 positive allosteric modulators (PAMs). The lead compound, 11c, exhibits excellent potency (EC(50)=30 nM) in vitro, and reaches high brain levels in both rats and mice after oral administration.

The discovery of the enzyme phosphodiesterase 10A (PDE10A) was reported simultaneously in 1999 by three independent groups. PDE10A has been shown by localisation studies to have the most restricted distribution of all the 11 known PDE families, with the PDE10A mRNA highly expressed only in the brain and testes. In the brain, mRNA and protein are highly enriched in the striatum and, together with increased pharmacological characterisation, this unique distribution of PDE10A in the brain indicates a potential use of PDE10A inhibitors for treating neurological and psychiatric disorders, in particular, psychotic disorders like schizophrenia. However, PDE10A inhibitors have also been claimed to be useful as treatment for cancer, diabetes and especially obesity. Two years after the reported discovery of PDE10A, Bayer filed the first patent application claiming PDE10A inhibitors, followed shortly thereafter by Pfizer. Since then, a number of scientific publications and filed patents testify to an increasing phar...

In addition to the total synthesis of the thiomethyl thiazole side chain analogue of epothilone B ( 3 ), a series of related trans -12,13-cyclopropyl epothilone B analogues ( 6 , 8 , 10 , 12 – 14 ) was accomplished. While the synthesis of the epothilone B analogue ( 3 ) proceeded through a Stille coupling of a vinyl iodide substrate containing the epothilone macrocycle with the appropriate side chain stannane, that of the cyclopropyl analogues ( 6 , 8 , 10 , 12 – 14 ) involved a convergent strategy in which a Nozaki–Hiyama–Kishi coupling as a means of introducing the side chains prior to Yamaguchi macrolactonization and final elaboration to the target molecules. The synthesized analogues were subjected to biological evaluation involving in vitro tubulin polymerization, affinity for the microtubule Taxol ® binding site and cell cytotoxicity assays. The results identified the methylthio thiazole side chain as a potency enhancing moiety for the epothilones and shed further light on the structure–activity relationships within this important class of chemotherapeutic agents.

A safe, practical, and scalable continuous flow protocol for the in situ generation of dimethylamine from DMF followed by nucleophilic aromatic substitution of a broad range of aromatic and heteroaromatic halides is reported.

In addition to the total synthesis of the thiomethyl thiazole side chain analogue of epothilone B ( 3 ), a series of related trans -12,13-cyclopropyl epothilone B analogues ( 6 , 8 , 10 , 12 – 14 ) was accomplished. While the synthesis of the epothilone B analogue ( 3 ) proceeded through a Stille coupling of a vinyl iodide substrate containing the epothilone macrocycle with the appropriate side chain stannane, that of the cyclopropyl analogues ( 6 , 8 , 10 , 12 – 14 ) involved a convergent strategy in which a Nozaki–Hiyama–Kishi coupling as a means of introducing the side chains prior to Yamaguchi macrolactonization and final elaboration to the target molecules. The synthesized analogues were subjected to biological evaluation involving in vitro tubulin polymerization, affinity for the microtubule Taxol ® binding site and cell cytotoxicity assays. The results identified the methylthio thiazole side chain as a potency enhancing moiety for the epothilones and shed further light on the structure–activity relationships within this important class of chemotherapeutic agents.