Design, synthesis and structure–activity relationships of 5-alkylaminolquinolines as a novel series of CRF1 receptor antagonists

Functionalized quinoxalinones as privileged structures with broad-ranging pharmacological activities

Quinoxalinones are a class of heterocyclic compounds which attract extensive attention owing to their potential in the field of organic synthesis and medicinal chemistry. During the past few decades, many new synthetic strategies toward the functionalization of quinoxalinone based scaffolds have been witnessed. Regrettably, there are only a few reports on the pharmacological activities of quinoxalinone scaffolds from a medicinal chemistry perspective. Therefore, herein we intend to outline the applications of multifunctional quinoxalinones as privileged structures possessing various biological activities, including anticancer, neuroprotective, antibacterial, antiviral, antiparasitic, anti-inflammatory, antiallergic, anti-cardiovascular, anti-diabetes, antioxidation, etc. We hope that this review will facilitate the development of quinoxalinone derivatives in medicinal chemistry.

Bioactive compounds from the seeds of Amomum tsaoko Crevost et Lemaire, a Chinese spice as inhibitors of sphingosine kinases, SPHK1/2

Amomum tsaoko Crevost et Lemaire (Zingiberaceae), a traditional Chinese spice also known as “Caoguo” or “tsao-ko,” has been considered to have many health benefits. As part of our continuous efforts to screen natural resources exhibiting potential bioactivity, we examined the seeds of A. tsaoko and found that its EtOH extract inhibited sphingosine kinases 1 and 2 (SPHK1/2). Bioactivity-based analysis and chemical investigation of the EtOH extract led to the isolation and identification of four aliphatic alcohols (1–4), five fatty acids (5–9), 12 phenolics (10–21), and four terpenoids (22–25), including four new compounds, an acetylated aliphatic alcohol (2), a fatty acid (5), and two phenolics (10–11). In addition, compound 1 was isolated for the first time from natural sources in this study. The structures of all compounds were elucidated based on spectroscopic analysis, including 1D and/or 2D NMR and HR-ESIMS as well as LC/MS analysis. A recently developed method using competing enantioselective acylation (CEA) coupled with LC/MS analysis was applied for the assignment of absolute configuration of compound 5. The absolute configurations of compounds 10 and 11 were determined using ECD calculations. All of the compounds (1–25) isolated from the active fraction were evaluated for their SPHK1/2 inhibitory effects at the concentration of 10 μM. Aliphatic alcohols 2–4, fatty acids 7 and 9, and phenolic compounds 13–15 and 21 showed inhibition against the activity of SPHK1 up to 20% and aliphatic alcohols 2 and 4, fatty acid 8, and phenolic compounds 10, 11, 18, and 22 showed inhibition against the activity of SPHK2 up to 40% compared with the control. Compound 2 showed the highest potency to inhibit SPHK1 enzymatic activity, by 59.75%, and compound 22 showed the highest potency in inhibiting the activity of SPHK2, by 22.75%, in comparison with the control, where both exhibited higher inhibition compared to those of positive controls. Docking modeling studies were conducted to suggest the binding mode of 2 and 22 in the substrate-binding pocket of SPHK1 and SPHK2, respectively.

New bioactive compounds were identified from the seeds of Amomum tsaoko Crevost et Lemaire, a Chinese spice as inhibitors of sphingosine kinases, SPHK1/2.

In silico binding mechanism prediction of benzimidazole based corticotropin releasing factor-1 receptor antagonists by quantitative structure activity relationship, molecular docking and pharmacokinetic parameters calculation

Despite the various research efforts toward the treatment of stress-related disorders, the drug has not yet launched last 20 years. Corticotropin releasing factor-1 receptor antagonists have been point of great interest in stress-related disorders. In the present study, we have selected benzazole scaffold-based compounds as corticotropin releasing factor-1 antagonists and performed 2D and 3D QSAR studies to identify the structural features to elucidating the binding mechanism prediction. The best 2D QSAR model was obtained through multiple linear regression method with r² value of .7390, q² value of .5136 and pred_r² (predicted square correlation coefficient) value of .88. The contribution of 2D descriptor, T_2_C_1 was 60% (negative contribution) and 4pathClusterCount was 40.24% (positive contribution) in enhancing the activity. Also 3D QSAR model was statistically significant with q² value of .9419 and q²_se (standard error of internal validation) value of .19. Statistical parameters results prove the robustness and significance of both models. Further, molecular docking and pharmacokinetic analysis was performed to explore the scope of investigation. Docking results revealed that the all benzazole compounds show hydrogen bonding with residue Asn283 and having same hydrophobic pocket (Phe286, Leu213, Ile290, Leu287, Phe207, Arg165, Leu323, Tyr327, Phe284, and Met206). Compound B14 has higher activity compare to reference molecules. Most of the compounds were found within acceptable range for pharmacokinetic parameters. This work provides the extremely useful leads for structural substituents essential for benzimidazole moiety to exhibit antagonistic activity against corticotropin releasing factor-1 receptors.

Monoterpene pyridine alkaloids and phenolics from Scrophularia ningpoensis and their cardioprotective effect

Scrophularianines A-C (1-3), three new unusual monoterpene pyridine alkaloids with cyclopenta [c] pyridine skeleton reported from the genus Scrophularia for the first time, together with 15 known compounds (4-18), were isolated from the extract of Scrophularia ningpoensis. Their structures were elucidated on the basis of extensive analyses of spectroscopic evidences. The biogenetic relationship between monoterpene pyridine alkaloids and iridoids was proposed preliminarily. The myocardial protective bioassay indicated that compounds 13 and 14 with a concentration of 10(-4)M exhibited significantly protective effect against H2O2-induced apoptosis in cardiomyocytes.