Divergent synthesis of fractionated Cannabis sativa extract led to multiple cannabinoids C-&O-glycosides with anti-proliferative/anti-metastatic properties.

Here, we present an interesting, previously unreported method for fractionating a particular class of cannabinoids from the crude leaf extract of Cannabis sativa using HP-20 resins. In this study, we report a novel method of divergent synthesis of fractionated Cannabis sativa extract, which allows the generation of multiple cannabinoids C- and O-glycosides which react with the glycosyl donor 2,3,4,6-tetra-O-acetyl-d-mannosyl trichloroacetimidate (TAMTA) to create eight C- and O-β-d-cannabinoids glycosides (COCG), which are separated by HPLC and whose structures are characterized by 1D, 2D NMR, and mass spectrometry. These glycosides exhibit improved anti-proliferative and anti-metastatic effects against numerous cancer cell lines in vitro and are more water-soluble and stable than their parent cannabinoids.

Study on antibody Fc-glycosylation for optimal effector functions.

A comprehensive structure-activity relationship study on antibody Fc-glycosylation has been performed using the chimeric anti-SSEA4 antibody chMC813-70 as a model. The α-2,6 sialylated biantennary complex type glycan was identified as the optimal Fc-glycan with significant enhancement in antibody effector functions, including binding to different Fc receptors and ADCC.

Unusual free oligosaccharides in human bovine and caprine milk.

Free oligosaccharides are abundant macronutrients in milk and involved in prebiotic functions and antiadhesive binding of viruses and pathogenic bacteria to colonocytes. Despite the importance of these oligosaccharides, structural determination of oligosaccharides is challenging, and milk oligosaccharide biosynthetic pathways remain unclear. Oligosaccharide structures are conventionally determined using a combination of chemical reactions, exoglycosidase digestion, nuclear magnetic resonance spectroscopy, and mass spectrometry.

Design and Synthesis of 6-O-Phosphorylated Heparan Sulfate Oligosaccharides to Inhibit Amyloid β Aggregation.

Dysregulation of amyloidogenic proteins and their abnormal processing and deposition in tissues cause systemic and localized amyloidosis. Formation of amyloid β (Aβ) fibrils that deposit as amyloid plaques in Alzheimer's disease (AD) brains is an earliest pathological hallmark. The polysulfated heparan sulfate (HS)/heparin (HP) is one of the non-protein components of Aβ deposits that not only modulates Aβ aggregation, but also acts as a receptor for Aβ fibrils to mediate their cytotoxicity.

Stereoselective Synthesis of Nonpsychotic Natural Cannabidiol and Its Unnatural/Terpenyl/Tail-Modified Analogues.

Here, we report a three-step concise and stereoselective synthesis route to one of the most important phytocannabinoids, namely, (-)-cannabidiol (-CBD), from inexpensive and readily available starting material -(+)-limonene. The synthesis involved the diastereoselective bifunctionalization of limonene, followed by effective elimination leading to the generation of key chiral -mentha-2,8-dien-1-ol. The chiral -mentha-2,8-dien-1-ol on coupling with olivetol under silver catalysis provided regiospecific (-)-CBD, contrary to reported ones which gave a mixture.

Practical Remdesivir Synthesis through One-Pot Organocatalyzed Asymmetric ()-P-Phosphoramidation.

Remdesivir, an inhibitor of RNA-dependent RNA polymerase developed by Gilead Sciences, has been used for the treatment of COVID-19. The synthesis of remdesivir is, however, challenging, and the overall cost is relatively high. Particularly, the stereoselective assembly of the P-chirogenic center requires recrystallization of a 1:1 isomeric -nitrophenylphosphoramidate mixture several times to obtain the desired diastereoisomer (39%) for further coupling with the d-ribose-derived 5-alcohol.

Total Synthesis of Phospholipomannan of .

First, total synthesis of the cell surface phospholipomannan anchor [β-Man-(1 → 2)-β-Man]-(1 → 2)-β-Man-(1 → 2)-α-Man-1 → -( → 6)-α-Man-(1 → 2)-Inositol-1--( → 1)-phytoceramide of is reported. The target phospholipomannan (PLM) anchor poses synthetic challenges such as the unusual kinetically controlled (1 → 2)-β-oligomannan domain, anomeric phosphodiester, and unique phytoceramide lipid tail linked to the glycan through a phosphate group. The synthesis of PLM anchor was accomplished using a convergent block synthetic approach using three main appropriately protected building blocks: (1 → 2)-β-tetramannan repeats, pseudodisaccharide, and phytoceramide-1--phosphonate.

Introducing Oxo-Phenylacetyl (OPAc) as a Protecting Group for Carbohydrates.

A series of oxo-phenylacetyl (OPAc)-protected saccharides, with divergent base sensitivity profiles against benzoyl (Bz) and acetyl (Ac) were synthesized, and KHSO/AcCl in methanol was identified as an easy, mild, selective, and efficient deprotecting reagent for their removal in the perspective of carbohydrate synthesis. Timely monitoring of AcCl reagent was supportive in both sequential and simultaneous deprotecting of OPAc, Bz, and Ac. The salient feature of our method is the orthogonal stability against different groups, its ease to generate different valuable acceptors using designed monosaccharides, and use of OPAc as a glycosyl donar.