Total Syntheses of Malabaricones B and C via a Cross-Metathesis Strategy

Insights into the inhibitory activities of neolignans and diarylnonanoid derivatives from nutmeg (Myristica fragrans Houtt.) seeds on soluble epoxide hydrolase using in vitro and in silico approaches

Two new neolignans, myrifralignans F-G (14 and 18), four new diarylnonanoid derivatives, myrifragranones A-D (21-24), and 18 known compounds were isolated and structurally elucidated from nutmeg (Myristica fragrans Houtt.) seeds. The absolute configurations of these secondary metabolites were determined using the electronic circular dichroism technique. The inhibitory potential of these isolated compounds on soluble epoxide hydrolase (sEH) was investigated for the first time. Among them, malabaricones B and C (19 and 20) and four new compounds 21-24 displayed inhibitory activities against sEH, with IC50 values ranging from 14.24 to 46.35 µM. Additionally, the binding mechanism, key binding interactions, stability, and dynamic behaviour of the active compounds with the sEH enzyme were analysed using in silico molecular docking and dynamics simulations. Our findings suggest that nutmeg could become a promising natural source for discovering and developing new sEH inhibitors.

Malabaricone C, a constituent of spice Myristica malabarica, exhibits anti-inflammatory effects via modulation of cellular redox

The present study primarily focuses on the efficacy of Malabaricone C (Mal C) as an anti-inflammatory agent. Mal C inhibited mitogen-induced T-cell proliferation and cytokine secretion. Mal C significantly reduced cellular thiols in lymphocytes. N-acetyl cysteine (NAC) restored cellular thiol levels and abrogated Mal C-mediated inhibition of T-cell proliferation and cytokine secretion. Physical interaction between Mal C and NAC was evinced from HPLC and spectral analysis. Mal C treatment significantly inhibited concanavalin A-induced phosphorylation of ERK/JNK and DNA binding of NF-κB. Administration of Mal C to mice suppressed T-cell proliferation and effector functions ex vivo. Mal C treatment did not alter the homeostatic proliferation of T-cells in vivo but completely abrogated acute graft-versus-host disease (GvHD)-associated morbidity and mortality. Our studies indicate probable use of Mal C for prophylaxis and treatment of immunological disorders caused due to hyper-activation of T-cells.

Borane promoted aryl transfer reaction for the synthesis of α-aryl functionalised β-hydroxy and β-keto esters

The synthesis of a series of α-aryl or α-alkyl functionalised β-hydroxy and β-keto esters has been achieved by reacting α-diazoesters with boranes, and aldehydes, ketones, anhydrides, nitriles, esters or isocyanates. In a mild reaction protocol, 26 examples are presented in yields up to 73%.

Malabaricone C Attenuates Nonsteroidal Anti-Inflammatory Drug-Induced Gastric Ulceration by Decreasing Oxidative/Nitrative Stress and Inflammation and Promoting Angiogenic Autohealing

Aims: Nonsteroidal anti-inflammatory drugs (NSAIDs), among the most commonly used drugs worldwide, are associated with gastrointestinal (GI) complications that severely limit the clinical utility of this essential class of pain medications. Here, we mechanistically dissect the protective impact of a natural product, malabaricone C (Mal C), on NSAID-induced gastropathy. Results: Mal C dose dependently diminished erosion of the stomach lining and inflammation in mice treated with NSAIDs with the protective impact translating to improvement in survival. By decreasing oxidative and nitrative stress, Mal C treatment prevented NSAID-induced mitochondrial dysfunction and cell death; nuclear factor κ-light-chain enhancer of activated B cell induction, release of proinflammatory cytokines and neutrophil infiltration; and disruptions in the vascular endothelial growth factor/endostatin balance that contributes to mucosal autohealing. Importantly, Mal C failed to impact the therapeutic anti-inflammatory properties of multiple NSAIDs in a model of acute inflammation. In all assays tested, Mal C proved as or more efficacious than the current first-line therapy for NSAID-dependent GI complications, the proton pump inhibitor omeprazole. Innovation: Given that omeprazole-mediated prophylaxis is, itself, associated with a shift in NSAID-driven GI complications from the upper GI to the lower GI system, there is a clear and present need for novel therapeutics aimed at ameliorating NSAID-induced gastropathy. Mal C provided significant protection against NSAID-induced gastric ulcerations impacting multiple critical signaling cascades contributing to inflammation, cell loss, extracellular matrix degradation, and angiogenic autohealing. Conclusion: Thus, Mal C represents a viable lead compound for the development of novel gastroprotective agents.