Total synthesis of a cyclopropane-fatty acid α-glucosyl diglyceride from Lactobacillus plantarum and identification of its ability to signal through Mincle

We report a concise synthesis of glycolipid GL1 from Lactobacillus plantarum commencing from methyl α-d-glucopyroside. A Jacobsen hydrolytic kinetic resolution is used to generate a diastereomerically-pure glycidyl glucoside that was elaborated to the diglyceride by stepwise brominolysis, acylation with oleoyl chloride, and bromide-substitution by the tetrabutylammonium salt of 9S,10R-dihydrosterculic acid. GL1 and analogues were shown to signal through the glycolipid pattern recognition receptor Mincle.

Total synthesis and structure-activity relationship of glycoglycerolipids from marine organisms

Glycoglycerolipids occur widely in natural products, especially in the marine species. Glycoglycerolipids have been shown to possess a variety of bioactivities. This paper will review the different methodologies and strategies for the synthesis of biological glycoglycerolipids and their analogs for bioactivity assay. In addition, the bioactivities and structure-activity relationship of the glycoglycerolipids are also briefly outlined.

The glycoglycerolipid 1,2-dipalmitoyl-3-(N-palmitoyl-6'-amino-6'-deoxy-α-d-glucosyl)-sn-glycerol is no inhibitor of the human Myt1 kinase

Previously, a glycoglycerolipid isolated from marine algae was reported to be a potent and selective inhibitor of the human Myt1 kinase, an enzyme involved in cell cycle regulation with great potential as an anti-cancer target. Based on that report, a lot of research effort has been invested by several working groups to synthesize and derivatize this compound. However, reliable assay data confirming the inhibitory potential and the mechanism of action of these glycoglycerolipids are missing so far. Here, based on experimental data and theoretical considerations, we show that the aforesaid glycoglycerolipid 1,2-dipalmitoyl-3-(N-palmitoyl-6'-amino-6'-deoxy-α-d-glucosyl)-sn-glycerol is not an inhibitor of the human Myt1 kinase.

Synthesis and antiviral evaluation of 6'-acylamido-6'-deoxy-α-D-mannoglycerolipids

Eight new aminomannoglycerolipids (2a-h) with linear, branched, or aromatic acyl chains were synthesized and evaluated for their anti-influenza A virus (IAV) activity. By comparing six mannosyl donors with different protecting and leaving groups, the critical glycosylation reaction employed mannosyl trichloroacetimidate with 2-O-benzoyl protecting group as the donor to give the glycoside with absolute α-anomeric selectivity. The bioactivity results showed that the branched compound 2g could effectively inhibit IAV multiplication in MDCK cells with IC50 69.9μM.