Synthesis of 7-azaindole based carbohydrazides and 1,3,4-oxadiazoles; Antioxidant activity, α-glucosidase inhibition properties and docking study

Design, synthesis and SAR of novel 7-azaindole derivatives as potential Erk5 kinase inhibitor with anticancer activity

The extracellular signal-regulated kinase 5 (Erk5) signaling plays a crucial role in cancer, and regulating its activity may have potential in cancer chemotherapy. In this study, a series of novel 7-azaindole derivatives (4a-5o) were designed and synthesized. Their antitumor activities on human lung cancer A549 cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 4',6-diamidino-2-phenylindole (DAPI) staining and colony formation assay. Among them, compounds 4a, 4 h, 5d and 5j exhibited good anti-proliferative activity with the IC50 values of 6.23 µg/mL, 8.52 µg/mL, 7.33 µg/mL and 4.56 µg/mL, respectively, equivalent to Erk5 positive control XMD8-92 (IC50 = 5.36 µg/mL). The results of structure-activity relationships (SAR) showed that double bond on the piperidine ring and N atoms at the N7 position of 7-azaindole was essential for their antiproliferative activity. Furthermore, compounds 4a and 5j exhibited good inhibition on Erk5 kinase through Western blot analysis and possible action site of compounds with Erk5 kinase was elucidated by molecular docking.

1,3,4-Oxadiazole and 1,3,4-Thiadiazole Nortopsentin Derivatives against Pancreatic Ductal Adenocarcinoma: Synthesis, Cytotoxic Activity, and Inhibition of CDK1

A new series of nortopsentin analogs, in which the central imidazole ring of the natural lead was replaced by a 1,3,4-oxadiazole or 1,3,4-thiadiazole moiety, was efficiently synthesized. The antiproliferative activity of all synthesized derivatives was evaluated against five pancreatic ductal adenocarcinoma (PDAC) cell lines, a primary culture and a gemcitabine-resistant variant. The five more potent compounds elicited EC₅₀ values in the submicromolar-micromolar range, associated with a significant reduction in cell migration. Moreover, flow cytometric analysis after propidium iodide staining revealed an increase in the G2-M and a decrease in G1-phase, indicating cell cycle arrest, while a specific ELISA demonstrated the inhibition of CDK1 activity, a crucial regulator of cell cycle progression and cancer cell proliferation.

Synthetic α-glucosidase inhibitors as promising anti-diabetic agents: Recent developments and future challenges

Diabetes mellitus is one of the biggest challenges for the scientific community in the 21st century. It is a well-recognized multifactorial health problem contributes significantly to high mortality rates by causing serious health complications mainly related to cardiovascular diseases, kidney damage and neuropathy. The inhibition of α-glucosidase (enzyme that catalyses starch hydrolysis in the intestine) is an effective therapeutic approach for controlling hyperglycemia associated with type-2 diabetes. However, the presently approved drugs/inhibitors such as acarbose, miglitol and voglibose have several undesirable gastrointestinal side effects impeding their applications. Therefore, search for novel and more effective inhibitors with reduced side effects and less cost remains a fascinating area of research. In this context, a large variety of α-glucosidase inhibitors have been identified in recent years that demands attention from drug development community. This review is therefore an effort to summarize and highlight the promising α-glucosidase inhibitors especially those which are primarily based on aromatic heterocyclic scaffolds such as coumarin, imidazole, isatin, pyrimidine, quinazoline, triazine, thiazole etc, having improved safety and pharmacological profiles.

Research progress on the synthesis and pharmacology of 1,3,4-oxadiazole and 1,2,4-oxadiazole derivatives: a mini review

Oxadiazole is a five-membered heterocyclic compound containing two nitrogen atoms and one oxygen atom. The 1,3,4-oxadiazole and 1,2,4-oxadiazole have favourable physical, chemical, and pharmacokinetic properties, which significantly increase their pharmacological activity via hydrogen bond interactions with biomacromolecules. In recent years, oxadiazole has been demonstrated to be the biologically active unit in a number of compounds. Oxadiazole derivatives exhibit antibacterial, anti-inflammatory, anti-tuberculous, anti-fungal, anti-diabetic and anticancer activities. In this paper, we report a series of compounds containing oxadiazole rings that have been published in the last three years only (2020–2022) as there was no report or their activities described in any article in 2019, which will be useful to scientists in research fields of organic synthesis, medicinal chemistry, and pharmacology.

α-Glucosidase and α-Amylase Inhibitory Potentials of Quinoline-1,3,4-oxadiazole Conjugates Bearing 1,2,3-Triazole with Antioxidant Activity, Kinetic Studies, and Computational Validation

Diabetes mellitus (DM) is a multifaceted metabolic disorder that remains a major threat to global health security. Sadly, the clinical relevance of available drugs is burdened with an upsurge in adverse effects; hence, inhibiting the carbohydrate-hydrolyzing enzymes α-glucosidase and α-amylase while preventing oxidative stress is deemed a practicable strategy for regulating postprandial glucose levels in DM patients. We report herein the α-glucosidase and α-amylase inhibition and antioxidant profile of quinoline hybrids 4a–t and 12a–t bearing 1,3,4-oxadiazole and 1,2,3-triazole cores, respectively. Overall, compound 4i with a bromopentyl sidechain exhibited the strongest α-glucosidase inhibition (IC₅₀ = 15.85 µM) relative to reference drug acarbose (IC₅₀ = 17.85 µM) and the best antioxidant profile in FRAP, DPPH, and NO scavenging assays. Compounds 4a and 12g also emerged as the most potent NO scavengers (IC₅₀ = 2.67 and 3.01 µM, respectively) compared to gallic acid (IC₅₀ = 728.68 µM), while notable α-glucosidase inhibition was observed for p-fluorobenzyl compound 4k (IC₅₀ = 23.69 µM) and phenyl-1,2,3-triazolyl compound 12k (IC₅₀ = 22.47 µM). Moreover, kinetic studies established the mode of α-glucosidase inhibition as non-competitive, thus classifying the quinoline hybrids as allosteric inhibitors. Molecular docking and molecular dynamics simulations then provided insights into the protein–ligand interaction profile and the stable complexation of promising hybrids at the allosteric site of α-glucosidase. These results showcase these compounds as worthy scaffolds for developing more potent α-glucosidase inhibitors with antioxidant activity for effective DM management.

Recent developments in the green synthesis of biologically relevant cinnolines and phthalazines

Both cinnolines and phthalazines are heterocyclic compounds which have a wide range of biological activities and pharmacological profiles. This work represents the recent advances in the green synthesis of cinnolines and phthalazines as 1,2 and 2,3-diazanaphalenes were cited. The docking studies and mode of action for key scaffolds were also reported.