Mini Reviews in Medicinal Chemistry - Volume 19, Issue 3, 2019

Preeclampsia (PE) has a profound effect in increasing both maternal and fetal morbidity and mortality especially in third World. Disturbances of extravillous trophoblast migration toward uterine spiral arteries is characteristic feature of PE, which, in turn, leads to increased uteroplacental vascular resistance and by vascular dysfunction resulting in reduced systemic vasodilatory properties. Underlying pathogenesis appeared to be an altered bioavailability of nitric oxide (NO•) and tissue damage caused by increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS). The increase in ROS and RNS production or the decrease in antioxidant mechanisms generates a condition called oxidative and nitrosative stress, respectively, defined as the imbalance between pro- and antioxidants in favor of the oxidants. Additionally, ROS might trigger platelet adhesion and aggregation leading to intravascular coagulopathy. ROS-induced coagulopathy causes placental infarction and impairs the uteroplacental blood flow in PE. As a consequence of these disorders could result in deficiencies in oxygen and nutrients required for normal fetal development resulting in fetal growth restriction. On the one hand, enzymatic and nonenzymatic antioxidants scavenge ROS and protect tissues against oxidative damage. More specifically, placental antioxidant enzymes including catalase, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) protect the vasculature from ROS, maintaining the vascular function. On the other hand, ischemia in placenta in PE reduces the antioxidant activity. Collectively, the extent of oxidative stress would increase and therefore leads to the development of the pathological findings of PE including hypertension and proteinuria. Our goal in this article is to review current literature about researches demonstrating the interplay between oxidative, nitrosative stresses and PE, about their roles in the pathophysiology of PE and also about the outcomes of current clinical trials aiming to prevent PE with antioxidant supplementation.

Marine sponges are a rich source of more than 50% of marine natural compounds that have been isolated from marine organisms. This review article is focused on the importance of biologically active and pharmaceutically important secondary metabolites extracted from one of the important classes of marine sponge Hyrtios sp. This review also deals with reported synthetic routes of some indole alkaloids extracted from the marine sponge Hyrtios sp. A range of bioactivities displayed by indole-based alkaloids is described.

Beauvericin (BEA) is a cyclic hexadepsipeptide, which derives from Cordyceps cicadae. It is also produced by Fusarium species, which are parasitic to maize, wheat, rice and other important commodities. BEA increases ion permeability in biological membranes by forming a complex with essential cations, which may affect ionic homeostasis. Its ion-complexing capability allows BEA to transport alkaline earth metal and alkali metal ions across cell membranes. Importantly, increasing lines of evidence show that BEA has an anticancer effect and can be potentially used in cancer therapeutics. Normally, BEA performs the anticancer effect due to the induced cancer cell apoptosis via a reactive oxygen species-dependent pathway. Moreover, BEA increases the intracellular Ca2+ levels and subsequently regulates the activity of a series of signalling pathways including MAPK, JAK/STAT, and NF-ΚB, and finally causes cancer cell apoptosis. In vivo studies further show that BEA reduces tumour volumes and weights. BEA especially targets differentiated and invasive cancer types. Currently, the anticancer activity of BEA is a hot topic; however, there is no review article to discuss the anticancer activity of BEA. Therefore, in this review, we have mainly summarized the anticancer activity of BEA and thoroughly discussed its underlying mechanisms. In addition, the human exposure risk assessment of BEA is also discussed. We hope that this review will provide further information for understanding the anticancer mechanisms of BEA.

Thiazole is the most common heterocyclic compound in heterocyclic chemistry and in drug design. Presence of several reaction sites in the thiazole moiety extends their range of applications and leads to new solutions for challenges in synthetic and medicinal chemistry. Thiazole derivatives are widely used as bioactive agents, liquid crystals, sensors, catalysts, etc. The motivating molecular architecture of 1,3-thiazoles makes them suitable moieties for drug development. In this review, our aim is to corroborate the recent data available on various synthetic strategies and biological properties of 1,3- thiazole derivatives.

Background: Bacterial resistance to the available antibiotics is a life threatening issue and researchers are trying to find new drugs to overcome this problem. Amongst the different structural classes, thiazolidinone-4-one, as a new effective pharmacophore against various bacteria, has been introduced. Objective: A new series of 2-(5-(5-nitrothiophene-2-yl)-1,3,4-thiadiazole-2-ylimino)-5-arylidenethiazolidin- 4-one derivatives were designed and synthesized as new antibacterial agents. Method: Target compounds were synthesized during 5 steps and their in vitro antibacterial and anti-H. pylori activities were evaluated. The interaction of the most active derivatives with the probable targets was assessed by Auto Dock 4.2 Program. Results: The results showed that the most potent compounds, 18, 22 and 23, displayed antibacterial activity versus S.aureus, S.epidermidis, B.cereus and B.subtilis (MIC, 1.56-12.5 μg/mL) and none of the derivatives were active on tested Gram-negative bacteria. Compound 12 in all considered doses and compounds 10, and 27 had strong anti-H. pylori activity (inhibition zone >20 mm) in 25 μg disc. Docking studies determined suitable interactions and affinity of potent compounds with bacterial MUR B and H. pylori urease enzymes. Conclusion: According to the results most of the derivatives are effective anti-bacterial agents and docking evaluation confirmed their possible mechanisms of actions as MURB and Urease inhibitors.

Objective: Inhibition of dipeptidyl peptidase IV (DPP-4) is currently one of the most valuable and potential chemotherapeutic regimes for the medication of Type 2 Diabetes Mellitus (T2DM). Method: Based on linagliptin, this study discusses the design, synthesis and biological evaluation of spiro cyclohexane-1,2'-quinazoline scaffold hybridized with various heterocyclic ring systems through different atomic spacers as a highly potent DPP-4 inhibitors. DPP-4 enzyme assay represented that most of the target compounds are 102-103 folds more active than the reference drug linagliptin (IC50: 0.0005-0.0089 nM vs 0.77 nM; respectively). Moreover, in vivo oral hypoglycemic activity assay revealed that most of the tested candidates were more potent than the reference drug, sitagliptin, producing rapid onset with long duration of activity that extends to 24 h. Interestingly, the derivatives 11, 16, 18a and 23 showed evidence of mild cytochrome P450 3A4 (CYP3A4) inhibition (IC50; > 210 μM) and their acute toxicity (LD50) was more than 1.9 gm/kg. Molecular simulation study of the new quinazoline derivatives explained the obtained biological results. Conclusion: Finally, we conclude that our target compounds could be highly beneficial for diabetic patients in the clinic.