Design, synthesis and biological evaluation of benzoxazolinone-containing 1,3,4-thiadiazoles as TNF-α inhibitors

The Benzoxazole Heterocycle: A Comprehensive Review of the Most Recent Medicinal Chemistry Developments of Antiproliferative, Brain-Penetrant, and Anti-inflammatory Agents

The benzoxazole is one of the most widely exploited heterocycles in drug discovery. Natural occurring and synthetic benzoxazoles show a broad range of biological activities. Many benzoxazoles are available for treating several diseases, and, to date, a few are in clinical trials. Moreover, an ever-increasing number of benzoxazole derivatives are under investigation in the early drug discovery phase and as potential hit or lead compounds. This perspective is an attempt to thoroughly review the rational design, the structure-activity relationship, and the biological activity of the most notable benzoxazoles developed during the past 5 years (period 2019-to date) in cancers, neurological disorders, and inflammation. We also briefly overviewed each target and its role in the disease. The huge amount of work examined suggests the great potential of the scaffold and the high interest of the scientific community in novel biologically active compounds containing the benzoxazole core.

New (S)-verbenone-isoxazoline-1,3,4-thiadiazole hybrids: synthesis, anticancer activity and apoptosis-inducing effect

Background: This study aimed to develop novel isoxazoline-1,3,4-thiadiazole hybrids from (S)-verbenone for potential anticancer treatment, particularly focusing on cytotoxic and apoptotic effects in hormone-sensitive MCF-7 and triple-negative MDA-MB-231 breast cancer cells. Methods & results: (S)-verbenone was used to synthesize hybrids through 1,3-dipolar cycloaddition, followed by thorough characterization. The compounds were screened across cancer cell lines, showing significant anticancer effects. Compound 8b notably induced apoptosis via the caspase-3/7 pathway and cell cycle arrest, displaying noteworthy cytotoxicity against MCF-7 and MDA-MB-231 cells. Conclusion: These findings underscore the potential of (S)-verbenone isoxazoline-1,3,4-thiadiazole derivatives for breast cancer therapy due to their remarkable apoptotic activity. This study highlights a promising avenue for advancing breast cancer treatment using these derivatives, founded on (S)-verbenone, showcasing their distinct potential for inducing apoptosis.

Synthesis and biological profile of benzoxazolone derivatives

The benzoxazolone nucleus is an ideal scaffold for drug design, owing to its discrete physicochemical profile, bioisosteric preference over pharmacokinetically weaker moieties, weakly acidic behavior, presence of both lipophilic and hydrophilic fragments on a single framework, and a wider choice of chemical modification on the benzene and oxazolone rings. These properties apparently influence the interactions of benzoxazolone-based derivatives with their respective biological targets. Hence, the benzoxazolone ring is implicated in the synthesis and development of pharmaceuticals with a diverse biological profile ranging from anticancer, analgesics, insecticides, anti-inflammatory, and neuroprotective agents. This has further led to the commercialization of several benzoxazolone-based molecules and a few others under clinical trials. Nevertheless, the SAR exploration of benzoxazolone derivatives for the identification of potential "hits" followed by the screening of "leads" provides a plethora of opportunities for further exploration of the pharmacological profile of the benzoxazolone nucleus. In this review, we aim to present the biological profile of different derivatives based on the benzoxazolone framework.

Discovery of Coixol Derivatives as Potent Anti-inflammatory Agents

Coixol, a derivative of 2-benzoxazolinone extracted from coix (Coix lachryma-jobi L. var. ma-yuen Stapf), has demonstrated promising anti-inflammatory activity and low cytotoxicity. In this study, 26 coixol derivatives were designed and synthesized by hybridization with cinnamic acid to identify new anti-inflammatory agents. The anti-inflammatory activities of the derivatives were screened using LPS-induced overexpression of nitric oxide (NO) in RAW264.7 macrophages. On the basis of the screening results, compounds containing furan (9c) or nitrofuran (9j) moieties displayed more pronounced activity than coixol and celecoxib. Mechanistic investigations revealed that 9c and 9j suppressed the expression of induced nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β, which was associated with the inhibition of the nuclear factor (NF)-κB signaling pathway. In vivo studies confirmed the anti-inflammatory activity of 9c and 9j in a xylene-induced mice auricles edema model. The preliminary in vitro and in vivo research findings suggest that 9c and 9j have the potential to be developed as anti-inflammatory agents.

RMD86, a thiophene derivative, promotes antinociceptive and antipyretic activities in mice

Treatment of pain and fever remains an important challenge for modern medicine. Non-steroidal anti-inflammatory drugs (NSAIDs) are the pharmacological options most often used, but their frequent use exposes the patient to serious side effects and dangerous drug interactions. In this context, thiophene derivatives are promising therapeutic alternatives. In this study, we evaluated the in vivo and in silico antinociceptive and antipyretic properties of RMD86, a thiophene derivative. At 100 mg/kg, RMD86 induced no significant changes in the motor coordination of mice in the Rotarod test. At 25, 50, and 100 mg/kg RMD86 significantly reduced the number of abdominal contortions induced by acetic acid (antinociceptive activity) in mice when compared to the control. In the formalin test, for the first phase, there was a reduction in licking times at doses of 50 and 100 mg/kg. In the second phase, reduction occurred at all doses. In the hot plate test, RMD86 (at 100 mg/kg) increased latency time in the first 30 min. For antipyretic activity, RMD86, when compared to the reference drug acetaminophen (250 mg/kg), significantly reduced pyrexia at 30, 60, and 120 min, at dosages of 25, 50 and 100 mg/kg. Molecular docking studies revealed that RMD86 presents a greater number of interactions and lower energy values than both the co-crystallized ligand and the reference drug (meloxicam) against COX-1 and COX-2 isoenzymes. The results give evidence of the analgesic and antipyretic properties like NSAIDs suggesting its potential for pain therapy.