Efficient O-trimethylsilylation of alcohols and phenols with trimethylsilyl azide catalyzed by tetrabutylammonium bromide under neat conditions

A very efficient procedure for the trimethylsilylation of a wide variety of alcohols, including primary, allylic, benzylic, secondary, hindered secondary, tertiary, and phenols is reported. The reactions were carried out under neat conditions with trimethylsilyl azide (TMSN(3)) and, when necessary, in the presence of a catalytic amount (20 mol %) of tetrabutylammonium bromide (TBABr) at 30 or 70 degrees C. Under catalytic conditions, the yields of the corresponding trimethylsilyl ethers were greater than 91%. This procedure also allows the selective protection of primary and secondary alcohols in the presence of tertiary ones.

Bromolysis and iodolysis of alpha,beta-epoxycarboxylic acids in water catalyzed by indium halides

The ring opening of alpha,beta-epoxycarboxylic acids by bromide and iodide ions has been efficiently carried out in water in high regio- and stereoselective fashion. The iodolysis of trans-beta-monoalkylated epoxycarboxylic acids at pH 4.0 was completely alpha-regioselective and anti diastereoselective. The InCl(3)-catalyzed iodolysis of a variety of alpha,beta-epoxycarboxylic acids at pH 1.5 gave the corresponding anti beta-iodohydrins in 88-95% yields. The one-pot synthesis of the alpha- and beta-hydroxyhexanoic acids, starting from the corresponding alpha,beta-epoxycarboxylic acid 1a by iodolysis followed by reduction of the resulting iodohydrins 4a and 4b by NaBH(4)-InCl(3) in water, has been performed.

Pharmacological characterization of GLPG1972/S201086, a potent and selective small-molecule inhibitor of ADAMTS5

OBJECTIVE

A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) is a key enzyme in degradation of cartilage in osteoarthritis (OA). We report the pharmacological characterization of GLPG1972/S201086, a new, potent and selective small-molecule ADAMTS5 inhibitor.

METHODS

Potency and selectivity of GLPG1972/S201086 for ADAMTS5 were determined using fluorescently labeled peptide substrates. Inhibitory effects of GLPG1972/S201086 on interleukin-1α-stimulated glycosaminoglycan release in mouse femoral head cartilage explants and on interleukin-1β-stimulated release of an ADAMTS5-derived aggrecan neoepitope (quantified with ELISA) in human articular cartilage explants were determined. In the destabilization of the medial meniscus (DMM) mouse and menisectomized (MNX) rat models, effects of oral GLPG1972/S201086 on relevant OA histological and histomorphometric parameters were evaluated.

RESULTS

GLPG1972/S201086 inhibited human and rat ADAMTS5 (IC50 ± SD: 19 ± 2 nM and <23 ± 1 nM, respectively), with 8-fold selectivity over ADAMTS4, and 60->5,000-fold selectivity over other related proteases in humans. GLPG1972/S201086 dose-dependently inhibited cytokine-stimulated aggrenolysis in mouse and human cartilage explants (100% at 20 μM and 10 μM, respectively). In DMM mice, GLPG1972/S201086 (30-120 mg/kg b.i.d) vs vehicle reduced femorotibial cartilage proteoglycan loss (23-37%), cartilage structural damage (23-39%) and subchondral bone sclerosis (21-36%). In MNX rats, GLPG1972/S201086 (10-50 mg/kg b.i.d) vs vehicle reduced cartilage damage (OARSI score reduction, 6-23%), and decreased proteoglycan loss (∼27%) and subchondral bone sclerosis (77-110%).

CONCLUSIONS

GLPG1972/S201086 is a potent, selective and orally available ADAMTS5 inhibitor, demonstrating significant protective efficacy on both cartilage and subchondral bone in two relevant in vivo preclinical OA models.

POS0442 GLPG4399: SELECTIVE SIK3 INHIBITION AS A NOVEL MODE OF ACTION FOR THE TREATMENT OF INFLAMMATORY ARTHRITIC DISEASES (PRECLINICAL)

Background

Salt-inducible kinases (SIKs) is a family of kinases with immunomodulatory function identified using a proprietary adenoviral shRNA knockdown target discovery platform. Moreover, SIK inhibition has previously been shown to have a role in inflammatory signalling.1–3 These findings suggest a therapeutic potential for SIK inhibition in inflammatory indications. A medicinal chemistry effort resulted in the development of a first-in-class, oral, selective SIK3 inhibitor: GLPG4399. This compound may be beneficial in inflammatory diseases such as rheumatoid and psoriatic arthritis which are chronic disorders characterized by impaired joint synovial inflammation.

Objectives

Our research aimed to characterize GLPG4399 and explore its impact in arthritis-relevant inflammatory in vitro phenotypic cell assays, and to evaluate the therapeutic potential of selective SIK3 inhibition in in vivo experimental models of arthritis.

Methods

The selectivity and potency of GLPG4399 was profiled using biochemical and target-based cell assays. The mode of action of selective SIK3 inhibition in inflammation was explored in an in vitro panel of innate (monocytes, macrophages, dendritic cells) and adaptive (B and T lymphocytes) immune phenotypic assays and in a lipopolysaccharide (LPS)-stimulated human whole blood assay by measuring the production of inflammatory cytokines. In vivo target engagement was evaluated in an acute LPS-stimulated cytokine release mouse model by measuring plasma tumour necrosis factor (TNF) α levels. The therapeutic efficacy of GLPG4399 was evaluated in vivo in collagen-induced arthritis (CIA) and IL-23-induced psoriatic arthritis mouse models by assessing disease activity endpoints.

Results

GLPG4399 was shown to be a SIK3 inhibitor with high selectivity against a panel of 370 kinases. The wide effect of SIK3 inhibition on key immune cell types was demonstrated by GLPG4399’s reduction of pro-inflammatory cytokines produced by monocytes, macrophages, dendritic cells, B and T lymphocytes in a panel of in vitro innate and adaptive immune phenotypic assays. The biological activity and target engagement of GLPG4399 was further demonstrated by dose-dependent inhibition of TNFα production in vitro in LPS-stimulated human whole blood and in vivo in the blood of LPS-challenged mice. Oral treatment with GLPG4399 in mice resulted in a significant and dose-dependent improvement of disease activity score in both CIA and the psoriatic arthritis disease model. Moreover, bone erosion in CIA and new bone formation in the psoriatic arthritis disease model were significantly reduced.

Conclusion

Our preclinical findings demonstrate the strong immunomodulatory effect of SIK3 inhibition in arthritis-relevant inflammatory cell assays and highlight the significant preclinical efficacy of GLPG4399 in two experimental arthritis mouse models. The novel mechanisms of action of GLPG4399 represents a promising approach for the treatment of arthritis.

References

[1]Sundberg TB et al. PNAS 2014;111:12468–73.

[2]Lombardi MS et al. J Leukoc Biol 2016;99:711–21.

[3]Wein MN et al. Trends Endocrinol Metab 2018;29:723–35.

Acknowledgements

These studies were funded by Galapagos NV (Mechelen, Belgium). Editorial and publications management support was provided by PharmaGenesis London, London, UK, and funded by Galapagos NV.

Disclosure of Interests

Stephanie Lavazais Employee of: Employee of Galapagos., Anna Pereira-Fernandes Employee of: Employee of Galapagos., Carole Delachaume Employee of: Employee of Galapagos., Catherine Jagerschmidt Employee of: Employee of Galapagos., Michael Drennan Employee of: Employee of Galapagos., Didier Merciris Employee of: Employee of Galapagos., Christophe Peixoto Employee of: Employee of Galapagos., Monica Borgonovi Employee of: Employee of Galapagos., Nicolas Desroy Employee of: Employee of Galapagos., David Amantini Employee of: Employee of Galapagos., Steve De Vos Employee of: Employee of Galapagos., Kris Nys Employee of: Employee of Galapagos.