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Nowadays, PI3Kδ-γ dual inhibitors have been approved for the treatment of B-cell malignancies. Dual inhibition of PI3Kδ and PI3Kγ represents a unique therapeutic opportunity and may confer greater benefits than either isoform inhibition alone in the management of hematological malignancies. However, currently available dual inhibitors of PI3Kδ-γ compromise in at least one of several essential properties in terms of potency, selectivity, and pharmacokinetic (PK) profiles. Hence, the main challenge of our optimization campaign was to identify an oral available PI3Kδ-γ dual inhibitor with an optimum balance of potency, selectivity, and PK profiles. The medicinal chemistry efforts culminated in the discovery of compound 58 , which exhibited strong potency and high selectivity along with excellent in vivo profiles as demonstrated through PK studies in rats and through pharmacodynamic studies in an SUDHL-6 xenograft model. All the results suggest that compound 58 may be a promising candidate for the treatment of B-cell malignancies.

Guided by molecular docking, a commonly used open-chain linker was cyclized into a five-membered pyrrolidine to lock the overall conformation of the propeller-shaped molecule. Different substituents were introduced into the pyrrolidine moiety to block oxidative metabolism. Surprisingly, it was found that a small methyl substituent could be used to alleviate the oxidative metabolism of pyrrolidine while maintaining or enhancing potency, which could be described as a "magic methyl". Further optimization around the "3rd blade" of the propeller led to identification of a series of potent and selective PI3Kδ inhibitors. Among them, compound 50 afforded an optimum balance of PK profiles and potency. Oral administration of 50 attenuated the arthritis severity in a dose-dependent manner in a collagen-induced arthritis model without obvious toxicity. Furthermore, 50 demonstrated excellent pharmacokinetic properties with high bioavailability, suggesting that 50 might be an acceptable candidate for treatment of inflammatory diseases.

TYK2 mediates signaling of IL-23, IL-12, and Type I IFN-driven responses that are critical in immune-mediated diseases. Herein, we report the design, synthesis, and structure-activity relationships (SARs) of 3-(4-(2-((1 H -indol-5-yl)amino)-5-fluoropyrimidin-4-yl)-1 H -pyrazol-1-yl)propanenitrile derivatives as selective TYK2 inhibitors. Among them, compound 14l exhibited acceptable TYK2 inhibition with an IC 50 value of 9 nM, showed satisfactory selectivity characteristics over the other three homologous JAK kinases, and performed good functional potency in the JAK/STAT signaling pathway on lymphocyte lines and human whole blood. In liver microsomal assay studies, the clearance rate and half-life of 14l were 11.4 mL/min/g and 121.6 min, respectively. Furthermore, in a dextran sulfate sodium colitis model, 14l reduced the production of pro-inflammatory cytokines IL-6 and TNF-α and improved the inflammation symptoms of mucosal infiltration, thickening, and edema. Taken together, 14l was a selective TYK2 inhibitor and could be used to treat immune diseases deserving further investigation.

In this study, we described a series of N -(pyrimidin-2-yl)-1,2,3,4-tetrahydroisoquinolin-6-amine derivatives as selective JAK2 (Janus kinase 2) inhibitors. Systematic exploration of the structure-activity relationship though cyclization modification based on previously reported compound 18e led to the discovery of the superior derivative 13ac . Compound 13ac showed excellent potency on JAK2 kinase, SET-2, and Ba/F3 V617F cells (high expression of JAK2 V617F mutation) with IC 50 values of 3, 11.7, and 41 nM, respectively. Further mechanistic studies demonstrated that compound 13ac could downregulate the phosphorylation of downstream proteins of JAK2 kinase in cells. Compound 13ac also showed good selectivity in kinase scanning and potent in vivo antitumor efficacy with 82.3% tumor growth inhibition in the SET-2 xenograft model. Moreover, 13ac significantly ameliorated the disease symptoms in a Ba/F3-JAK2 V617F allograft model, with 77.1% normalization of spleen weight, which was more potent than Ruxolitinib.

Herein, we describe the design, synthesis, and structure-activity relationships of a series of unique 4-(1 H -pyrazol-4-yl)-pyrimidin-2-amine derivatives that selectively inhibit Janus kinase 2 (JAK2) and FLT3 kinases. These screening cascades revealed that 18e was a preferred compound, with IC 50 values of 0.7 and 4 nM for JAK2 and FLT3, respectively. Moreover, 18e was a potent JAK2 inhibitor with 37-fold and 56-fold selectivity over JAK1 and JAK3, respectively, and possessed an excellent selectivity profile over the other 100 representative kinases. In a series of cytokine-stimulated cell-based assays, 18e exhibited a higher JAK2 selectivity over other JAK isoforms. The oral administration of 60 mg/kg of 18e could significantly inhibit tumor growth, with a tumor growth inhibition rate of 93 and 85% in MV4-11 and SET-2 xenograft models, respectively. Additionally, 18e showed an excellent bioavailability ( F = 58%), a suitable half-life time ( T 1/2 = 4.1 h), a satisfactory metabolic stability, and a weak CYP3A4 inhibitory activity, suggesting that 18e might be a potential drug candidate for JAK2-driven myeloproliferative neoplasms and FLT3-internal tandem duplication-driven acute myelogenous leukemia.

A series of 7H-pyrrolo[2,3-d]pyrimidine derivatives were designed and synthesized as reversible BTK inhibitors, and evaluated their kinase selectivity, anti-proliferation against the B-cell lymphoma cell lines (Ramos, Jeko-1) and cell line BTK enhanced (Daudi) in vitro. Among them, compound 28a exhibited the most excellent potency (IC 50  = 3.0 nM against BTK enzyme, 8.52 μM, 11.10 μM and 7.04 μM against Ramos, Jeko-1, Daudi cells, respectively), good kinase selectivity and inhibited BTK Y223 auto-phosphorylation and PLCγ2 Tyr1217 phosphorylation. Importantly, 28a showed efficacy anti-arthritic effect on collagen-induced arthritis (CIA) model in vivo. 28a 60 mg/kg dose level once a day group displayed markedly reduced joint damage and cellular infiltration without any bone and cartilage morphology change., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Background: This study was designed to assess the clinical efficacy and toxicity of apatinib (YN968D1) as third or subsequent-line treatment for stage III/IV non-small cell lung cancer (NSCLC)., Methods: A total of 100 patients with advanced NSCLC who were treated with apatinib at a daily dose of 250/425/500 mg at Shandong Cancer Hospital from January 2016 to June 2018 were enrolled in our study. The objective response, disease control, and median progression-free survival rates were reviewed and evaluated. Univariate and multivariate analyses were performed to determine the prognostic factors. The main adverse events were evaluated per the Common Terminology Criteria for Adverse Events version 4.0., Results: All patients were assessable for response. No complete responses were observed, 11 patients achieved a partial response, and 56 showed stable disease. The objective response rate was 11.0%, the disease control rate was 67.0%, and the median progression-free survival was 2.93 months (95% confidence interval 2.07-3.87). In Cox regression analysis, the Eastern Cooperative Oncology Group performance status score (hazard ratio 1.799; P < 0.05) and smoking history (hazard ratio 1.958; P < 0.05) were predictive indicators for apatinib treatment efficacy. Treatment-related adverse events were tolerated, predictable, reversible, and controllable., Conclusion: Apatinib was found to be both effective and safe in advanced NSCLC patients without a genetic driver mutation who experienced progression after two or more lines of chemotherapy treatment., (© 2018 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Here, we report the design and synthesis of pyrimidinyl heterocyclic compounds containing terminal electrophiles as irreversible covalent JAK3 inhibitors that exploit a unique cysteine (Cys909) residue in JAK3. Investigation of the structure-activity relationship utilizing kinase assays resulted in the identification of potent and selective JAK3 inhibitors such as T1, T8, T15, T22, and T29. Among them, T29 was verified as a promising JAK3 irreversible inhibitor that possessed the best bioactivity and selectivity against JAKs and kinases containing a cysteine in the residue analogous to Cys909 in JAK3, suggesting that covalent modification of this Cys residue allowed the identification of a highly selective JAK3 inhibitor. Moreover, T29 also displayed a significant anti-inflammatory effect in ICR mice through the inhibition of increased paw thickness, which is worth further optimization to increase its potency and medicinal properties.

Bruton's tyrosine kinase (Btk) is a Tec family kinase with a well-defined role in the B cell receptor (BCR) and Fcγ receptor (FcR) signaling pathways, which makes it a uniquely attractive target for the treatment of autoimmune diseases, such as rheumatoid arthritis (RA). We reported a series of compounds bearing 7H-pyrrolo [2,3-d]pyrimidin-4-amine scaffold that potently inhibited Btk in vitro. Analysis of the structure-activity relationships (SAR) and drug-like profiles led to the discovery of the optimal compound B16. B16 preferentially inhibited Btk (IC 50  = 21.70 ± 0.82 nM) over closely related kinases with moderate selectivity. Cell-based tests also confirmed that B16 significantly inhibited Btk Y223 auto-phosphorylation and PLCγ2 Y1217 phosphorylation. MTT revealed that B16 displayed weak suppression against normal LO2, HEK293 and THP-1 cell lines with IC 50 values over 30 μM. Moreover, B16 showed very weak potential to block the hERG channel (IC 50  = 11.10 μM) in comparison to ibrutinib (IC 50  = 0.97 μM). Owing to its favorable physicochemical properties (ClogP = 2.53, aqueous solubility ≈ 0.1 mg/mL), pharmacokinetic profiles (F = 49.15%, t 1/2  = 7.02 h) and reasonable CYP450 profile, B16 exhibited potent anti-arthritis activity and similar efficacy to ibrutinib in reducing paw thickness in CIA mice. In conclusion, B16 is a potent, selective and durable inhibitor of Btk and has the potential to a safe and efficacious treatment for arthritis., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Selective inhibition of Janus kinase 3 (JAK3) has been identified as an important strategy for the treatment of autoimmune disorders. Based on the unique cysteine 909 residue (Cys909) of JAK3 at the gatekeeper position, we have developed a new irreversible covalent inhibitor, III-4, which is highly potent and selective in targeting JAK3. Importantly, III-4 selectively inhibited JAK3 (IC 50  = 57 ± 1.21 nM) over other JAKs (IC 50  > 10 µM) and Cys909 kinome members (IC 50  > 1 µM). A cellular selectivity study also confirmed that III-4 preferentially inhibited JAK3 over JAK1 in JAK/STAT signaling. Moreover, the fact that III-4 covalently modified the Cys909 residue in JAK3 was clearly validated by mass spectrometry and covalent docking analysis. Based on the favorable target profiles, the pharmacokinetic properties and its low toxicity, III-4 exhibited better efficacy than tofacitinib in impeding disease progression in CIA mice, without any significant adverse effects. Taken together, III-4 is a potent, selective, and durable inhibitor of JAK3 and has the potential for the treatment of inflammatory disorders and autoimmune diseases, such as rheumatoid arthritis., (© 2017 Deutsche Pharmazeutische Gesellschaft.)

Described as a Btk inhibitor, ibrutinib also potently inhibits Bmx and EGFR, two good targets for lung cancer. Owing to its high CLogP (4.07) and low aqueous solubility (<0.01mg/ml), resulting in unfavorable bioavailability, ibrutinib requires high dosages to achieve good clinical response in the treatment of non-small cell lung cancer (NSCLC). In our effort to improve the CLogP of ibrutinib by structural optimization led to the discovery of a potent anti-cancer agent B6, with beneficial physicochemical parameters (CLogP=2.56, solubility in water≈0.1mg/ml) meeting the principles of oral drugs. B6 exhibited anti-proliferation activities against EGFR-expressing cells, especially the mutant ones, such as H1975 (L858R/T790M, IC 50 =0.92±0.19μM) and HCC827 (Del119 IC 50 =0.014±0.01μM). Moreover, B6 significantly slowed down H1975 tumor growth with anti-tumor rate of 73.9% (p<0.01). Enzyme potencies assay demonstrated B6 moderately selectively inhibited Bmx (IC 50 =35.7±0.1nM) over other kinases. So, as a potent Bmx inhibitor, B6 has the potential to be an efficacious treatment for NSCLC with acquired drug resistance., (Copyright © 2017. Published by Elsevier Ltd.)