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N-Arachidonoyl-ethanolamine (AEA) is an endocannabinoid (eCB) and endogenous lipid mimicking many of the effects of Δ9-tetrahydrocannabinol, notably on brain functions, appetite, pain and inflammation. The eCBs and eCB-like compounds contain fatty acids, the main classes being the monoacylglycerols and the N-acyl-ethanolamines (NAEs). Thus, each long chain fatty acid likely exists under the form of a monoacylglycerol and NAE, as it is the case for arachidonic acid (AA) and linoleic acid (LA). Following their biosynthesis, AA and AEA can be further metabolized into additional eicosanoids, notably by the 15-lipoxygenase pathway. Thus, we postulated that NAEs possessing a 1Z,4Z-pentadiene motif, near their omega end, would be transformed into their 15-lipoxygenase metabolites. As a proof of concept, we investigated N-linoleoyl-ethanolamine (LAE). We successfully synthesized LEA and LEA-d4 as well as their 15-lipoxygenase-derived derivatives, namely 13-hydroxy-9Z,11E-octadecadienoyl-N-ethanolamine (13-HODE-EA) and 13-HODE-EA-d4, using Novozyme 435 immobilized on acrylic resin and soybean lipoxygenase respectively. We also show that both human 15-lipoxygenase-1 and -2 can biosynthesize 13-HODE-EA. Co-incubation of LEA and LA with either human 15-lipoxygenase led to the biosynthesis of 13-HODE-EA and 13-HODE in a ratio equal to or greater than 3:1, indicating that LEA is preferred to LA by these enzymes. Finally, we show that 13-HODE-EA is found in human saliva and skin and is a weak although selective TRPV1 agonist. The full biological importance of 13-HODE-EA remains to be explored.

CXCR4 chemokine receptor represents an attractive pharmacological target due to its key role in cancer metastasis and inflammatory diseases. Starting from our previously-developed pharmacophoric model, we applied a combined computational and experimental approach that led to the identification of the hydantoin alkaloids parazoanthines, isolated from the Mediterranean Sea anemone Parazoanthus axinellae, as novel CXCR4 antagonists. Parazoanthine analogues were then synthesized to evaluate the contribution of functional groups to the overall activity. Within the panel of synthesized natural and non-natural parazoanthines, parazoanthine-B was identified as the most potent CXCR4 antagonist with an IC50 value of 9.3 nM, even though all the investigated compounds were able to antagonize in vitro the down-stream effects of CXC12, albeit with variable potency and efficacy. The results of our study strongly support this class of small molecules as potent CXCR4 antagonists in tumoral pathologies characterized by an overexpression of this receptor. Furthermore, their structure–activity relationships allowed the optimization of our pharmacophoric model, useful for large-scale in silico screening.

BACKGROUND The endocannabinoids 2-AG and AEA are lipids regulating many physiological processes, notably inflammation. The endocannabinoidome includes other monoacylglycerols (MAG) and N-acyl-ethanolamines (NAE) such as 1-linoleoyl-glycerol (1-LG) and N-linoleoyl-ethanolamine (LEA). Endocannabinoid hydrolysis inhibitors are now being tested as potential anti-inflammatory agents. By increasing MAG and/or NAE levels, these inhibitors will likely increase the levels of their metabolites. Herein we investigated whether 1-LG and LEA were substrates for the 15-lipoxygenase pathway, which is strongly involved in asthma and its severity. We thus assessed how human eosinophils and neutrophils biosynthesized the 15-lipoxygenase metabolites of 1-LG and LEA. Linoleic acid (LA), a well-documented substrate of 15-lipoxygenases, was used as positive control. RESULTS We synthesized the putative 15-lipoxygenase metabolites of 1-LG and LEA using Novozym435 and soybean lipoxygenase. Eosinophils, which express the 15-lipoxygenase-1, metabolized LA, 1-LG, and LEA into their 13-hydroxy derivatives. This was almost complete after 5 minutes. Substrate preference of eosinophils was LA>LEA>1-LG. Human neutrophils, which express the 15-lipoxygenase-2, also metabolized LA, 1-LG, and LEA into their 13-hydroxy derivatives. This was maximal after 30 seconds. Substrate preference was LA≫1-LG>LEA. Importantly, the new 15-lipoxygenase metabolites we disclose were found in tissues from humans and mice. CONCLUSIONS We successfully showed that human eosinophils and neutrophils transforms 1-LG and LEA into novel 15-lipoxygenase metabolites. How these new metabolites modulate the inflammatory cascade is now being explored.

The investigation is related to the development of a general strategy for the synthesis of glycolipids including analogs bearing polyunsaturated fatty acids. In particular, here we report exceptionally mild and selective conditions to remove acetate protecting groups from glyceroglycolipids by hydrazinolysis. Synthetic 1,2-O-di-arachidonoyl-3-O-beta-galactosyl-glycerol was used as representative of polyunsaturated beta-galactosyl-di-acyl-glycerols due to its reactivity under the conditions usually employed in literature. (C) 2016 Elsevier Ltd. All rights reserved.

A versatile synthesis of the natural product parazoanthine B (2) and its analogs, parazoanthine C (3) and 18-deoxy-parazoanthine B (4), has been accomplished by a key coupling reaction between a hydantoinic compound and an α-bromo-acetophenone derivative. The synthetic approach is designed to address preparation of a wider group of parazoanthine B analogs characterized by the presence of the 5,6-double bond of Z-configuration.

Fluorescent galactolipid analogues (1, 1a, and 2) have been synthesized with a pyrene group attached to the amino-terminal of a hexanoyl chain bound to an otherwise normal galactolipid structure. The synthetic lipids are obtained from peracetyl galactose by a general and versatile procedure based on the trichloroacetimidate methodology. The intense violet fluorescence (376 and 395 nm) and good photostability of pyrene make these compounds highly suitable as probes to study galactolipid metabolism. As proof of concept, we report that compound 2 is a valid tool to detect galactolipase activity in enzymatic preparations of potato tubers. (C) 2014 Elsevier Ltd. All rights reserved.

A simple synthesis of the major oxidized metabolites in mammalian tissues of (-)-Delta(9)-tetrahydrocannabivarin (THCV) (1) has been accomplished by kinetic studies of allylic oxidation using SeO2 on botanically derived THCV with the aim to yield primary and secondary allylic alcohols concurrently. This synthetic approach led to the preparation of numerous THCV derivatives, including two new compounds, 8 alpha-hydroxy-Delta(9)-tetrahydrocannabivarin (2) and 8 beta-hydroxy-Delta(9)-tetrahydrocannabivarin (3), and the known compounds 11-hydroxy-Delta(9)-tetrahydrocannabivarin (4) and Delta(9)-tetrahydrocannabivarin-11-oic acid (5), without affecting the C-10a stereogenic center in the natural precursor and without formation of tricyclic dibenzopyran derivatives. This simple synthetic methodology could be useful to investigate the pharmacological role of THCV metabolites at, among others, the endocannabinoid CB1 and CB2 receptors for which THCV reportedly acts as respectively a neutral antagonist and partial agonist.