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Selective modification of the hydroxyl groups of sugars has been a long-standing challenge due to their proximate relative reactivity. Herein, we report a TMSOTf-catalyzed selective acetylation of the non-anomeric hydroxyl groups of several per-O-TMS-protected sugar substrates while leaving their anomeric group unaffected. In addition to standing versatile by itself, the anomeric O-TMS group left intact can be functionalized to afford key sugar precursors such as imidate donors, which could otherwise be synthesized via a stepwise anomeric deprotection-functionalization procedure.

The trimethylsilyl (TMS) group is widely used in carbo?hydrate synthesis, although this protecting group is unstable and its post-synthetic purification challenging. The successful trimethylsilyl?ation of carbohydrates mediated by recyclable and efficient

Cholesteryl α-d-glucosides (αGCs) are unique metabolic products of the cancer-causing human pathogenHelicobacter pylori.Viasignalling through the Macrophage inducible C-type lectin (Mincle) and the induction of a pro-inflammatory response, they are thought to play a role in the development of gastric atrophy. Herein, we prepared the first library of steryld-glucosides and determined that they preferentially signal through the carbohydrate recognition domain of human Mincle, rather than the amino acid consensus motif. Lipidated steryld-glucosides exhibited enhanced Mincle agonist activity, with C18 cholesteryl 6-O-acyl-α-d-glucoside (2c) being the most potent activator of human monocytes. Despite exhibiting strong Mincle signalling, sito- (5b) and stigmasterol glycosides (6b) led to a poor inflammatory response in primary cells, suggesting that Mincle is a potential therapeutic target for preventingH. pylori-mediated inflammation and cancer.

A palladium-catalyzed C-O bond formation reaction between phenols and allenylic carbonates to give 2,3-allenic aromatic ethers with decent to excellent yields under mild reaction conditions has been described. A variety of synthetically useful functional

KRN7000 is particularly useful because it is a powerful and specific CD1d agonist and has prompted intense interest in the context of immunology in the past 25 years. Its limited commercial availability and high price has led to the publication of many different syntheses. However, almost all of them focused on the methodology development rather than a scalable synthesis. Herein, we have described a practical and scalable procedure for the synthesis of KRN7000 basing on the glycosyl iodide method. This procedure involves total of eight steps to obtain the highly pure product KNR7000 on gram scale from the commercially available starting materials (d-galactose and the phytosphingosine) with only three column chromatographic purifications.

The invention discloses a novel lipid material for realizing the delivery of a breast cancer targeted drug. The novel lipid material takes lysine as a connecting group and is connected with a cholesteric part, a biotin part and a glucose part. The affinity between biotin and glucose in the novel lipid material and biotin transporter (SMVT) and glucose transporter (GLUT1) can be utilized to realizethe double targeting function to breast cancer and play a stronger breast cancer targeting therapeutic role, wherein the biotin transporter (SMVT) and the glucose transporter (GLUT1) are highly expressed on the surface of breast cancer cells. The novel lipid material can be used in different dosage forms comprising liposomes, nanoparticles, micelles and the like, and the prepared paclitaxel-loaded liposome has obvious breast cancer targeting property and a wide application prospect.

Breast cancer is the second leading cause of cancer-related deaths in women. Ligand-modified liposomes are used for breast tumor-specific drug delivery to improve the efficacy and reduce the side effects of chemotherapy; however, only a few liposomes with high targeting efficiency have been developed because the mono-targeting, ligand-modified liposomes are generally unable to deliver an adequate therapeutic dose. In this study, we designed biotin-glucose branched ligand-modified, dual-targeting liposomes (Bio-Glu-Lip) and evaluated their potential as a targeted chemotherapy delivery system in vitro and in vivo. When compared with the non-targeting liposome (Lip), Bio-Lip, and Glu-Lip, Bio-Glu-Lip had the highest cell uptake in 4T1 cells (3.00-fold, 1.60-fold, and 1.95-fold higher, respectively) and in MCF-7 cells (2.63-fold, 1.63-fold, and 1.85-fold higher, respectively). The subsequent cytotoxicity and in vivo assays further supported the dual-targeting liposome is a promising drug delivery carrier for the treatment of breast cancer.

To improve aqueous solubility and anti-ischemic activity of 3-n-butylphthalide (NBP), we designed and synthesized the ring-opened derivative of NBP-ferulic acid-glucose trihybrids (S1-S8). These hybrids inhibited adenosine diphosphate (ADP)- or arachidonic acid (AA)-induced platelet aggregation, among them, S2 was 30-fold more water-soluble, and over 10-fold more potent in inhibition of platelet aggregation, as well as reduced ROS generation and protected primary neuronal cells from OGD/R-induced damage, in comparison with NBP. Additionally, S2 was more active than its three moieties alone or in combination, suggesting that the activity of S2 may be attributed to the synergistic effects of these moieties. Importantly, in vivo studies indicated that S2 not only possessed good pharmacokinetic profile, but also improved NBP distribution in rodent brain, suggesting that the glucose moiety in S2 may be recognized by glucose transporter 1 (GLUT1) on blood-brain barrier (BBB), promoting it to penetrate through BBB. Our findings suggest that S2 may be a promising candidate for the intervention of ischemic stroke, warranting further study.

α-Glucosyl diacylglycerols (αGlc-DAGs) play an important role in providing protective immunity against Streptococcus pneumoniae infection through the engagement of the Macrophage inducible C-type lectin (Mincle). Herein, we efficiently synthesised αGlc-DAGs containing C12, C14, C16 and C18 acyl chains in 7 steps and 44–47% overall yields, and demonstrated that Mincle signaling was dependent on lipid length using mMincle and hMincle NFAT-GFP reporter cells. The greatest production of GFP in both cell types was elicited by C14 αGlc-DAG. Accordingly, C14 αGlc-DAG has potential to act as an adjuvant to augment the immune response against S. pneumoniae antigens.

PROBLEM TO BE SOLVED: To provide means of improving immunostimulation activity of α-galactosylceramide. SOLUTION: The invention provides a compound represented by the general formula (I) in the figure, where Ar represents an aryl group that may be substituted with substituents such as a phenyl group, or a heteroaryl group that may be substituted with substituents, and n represents an integer from 4 to 12. SELECTED DRAWING: None COPYRIGHT: (C)2020,JPOandINPIT

Chemical syntheses of the bacterial diglucosyl diacylglycerols 1-heptadecanoyl-2-pentadecanoyl-3-O-[6-O-(β-d-glucopyranosyl)-β-d-glucopyranosyl]-sn-glycerol and 1-(cis-13-octadecenoyl)-2-palmitoyl-3-O-[2-O-(α-d-glucopyranosyl)-α-d-glucopyranosyl]-sn-glycerol are described. The syntheses feature the stereoselective construction of glycosidic linkages in glycosylation reaction by utilizing glycosyl donors with stereodirecting cyclic silyl protective groups. The 1,1,3,3-tetraisopropyldisiloxane-1,3-diyl (TIPDS) group was used for formation of the β-glycosidic linkage, while the di-tert-butylsilylene (DTBS) group was used for α-linkage formation. The silyl protective groups were chemoselectively cleavable without affecting acyl functionalities on the glycerol moiety and proved effective for the synthesis of diacylglycoglycerolipids.

Poly(methylhydrosiloxane) (PMHS) has been examined for its ability to reduce and subsequently cyclize carbohydrate substrates using catalytic tris(pentafluorophenyl)borane (BCF). The work herein is the first reported example of the direct conversion of monosaccharides to 1,4-anhydro and 2,5-anhydro products utilizing a hydrosiloxane reducing agent. PMHS is produced from waste products of the silicone industry, making it a green alternative to traditional hydrosilane reducing agents. This work thus contributes to the goal of utilizing renewable feedstocks in the production of fine-chemicals.

The bacterium Pantoea ananatis was reported to produce glycolipid biosurfactants of unknown structures. Herein, we present the isolation and structural determination of ananatoside A, the main congener of a new family of 15-membered macrodilactone-containing glucolipids. The structure of ananatoside A was elucidated via chemical degradation and spectroscopic methods including 1D/2D NMR analysis, tandem MS/MS, GC-MS, HR-ESI-TOF-MS, MALDI-TOF-MS, and polarimetry. Computational methods were used to predict the most abundant conformers of ananatoside A.

The invention belongs to the technical field of medicines, and particularly relates to a camptothecin saccharide conjugate and a preparation method and application thereof. The camptothecin saccharide conjugate is obtained by connecting camptothecin and hexose through adipic acid serving as a linker. Experimental results show that the camptothecin saccharide conjugate has an anti-tumor effect and has an efficient and low-toxicity effect compared with camptothecin. Experimental GLUT1 results show that the camptothecin saccharide conjugate of the present invention can be identified and transported, and the camptothecin saccharide conjugate GLUT1 of the present invention GLUT1 can be used as a cytotoxic quinoline alkaloid, and can DNA be used as a cytotoxic quinoline alkaloid (TOPO I). (by machine translation)

Phytochemical investigation of the roots of Solanum melongena L. resulted in the isolation of six new steroidal saponins, including five new cholestane saponins (1-5) and one new steroidal alkaloid (6), along with one new natural product (7) and three know steroids (8-10). The structures of all isolated compounds were determined by 1D and 2D NMR experiments and by comparison of their spectroscopic and physical data with literature values. The inhibitory activities on nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in a RAW 264.7 cell line were assayed for all the isolated compounds. Compounds 1, 2 and 4–9 exhibited moderate inhibition of NO production with IC50 values ranging from 12.6 to 59.5 μM.

Two new lignans, zanthoxyloside C (1) and zanthoxyloside D (2), together with nine known compounds comprising lignans (3–5), flavonoids (6–8), and phenolics (9–11), were isolated from the methanol extract of the stems of Zanthoxylum piperitum. All isolates were evaluated for their antioxidant and anti-osteoporotic activities using oxygen radical absorbance capacity (ORAC), cupric reducing antioxidant capacity (CUPRAC), and tartrate-resistant acid phosphatase (TRAP) assays. Compounds 7–10 showed peroxyl radical-scavenging capacities and 4, 6–7, and 9 showed reducing capacities. Moreover, compounds 3, 6–9, and 11 significantly suppressed TRAP activities. These results indicated that the stems of Z. piperitum could be an excellent source for natural antioxidant and anti-osteoporosis.

The invention discloses a preparation of glucose modified novel brain-targeted magnetic nanoparticle, which is a structure or its pharmaceutically acceptable salts and hydrate shown in general formula(I); the formula is as shown in description, wherein X represents one terminal carboxylated polyethylene glycol PEG, the PEG molecular weight of triethylene glycol, tetraglycol or polyethylene glycolis 200, 400, 600, 800, 1000, 1500, 2000, 4000 an dothers; Y represents (CH2)a , C(O) (CH2)a C(O) or O (CH2)b , NH (CH2)b , C(O) (CH2)b , C(O) (CH2)b C(O) ; a represents 0-6; b represents 1-4;MNPs represents Fe3O4, gama-Fe2O3, MnFe2o4, CoFe2O4 and ZnFe2O4, and others; Drug represents the drug applied to a neutral nerve system. The preparation of glucose modified novel brain-targeted magnetic nanoparticle can be used as the carrier for the treatment of the neutral nerve system disease, and has the magnetic-targeting direction of ferroferric oxide nanoparticle as well as the active brain-targeting effect of glucose.

The invention discloses a novel lipid material. The novel lipid material is used for prolonging the circulating time and increasing the transfer amount of medicine to brain tumor tissues in a target way. The novel lipid material is characterized in that polyethylene glycol is used as a bridge, one side of the bridge is connected with cholesterol, and one side of the bridge is connected with glucose and RGD (arginine-glycine-aspartic acid) peptide, so that the lack of brain tumor targeting ability by the lipid modified by the single glucose or the RGD peptide is overcome, and the brain tumor can be effectively targeted after blood brain barrier crossing. The novel lipid material can be used for different preparation types of lipids, nanoparticles, micelles and the like; the prepared paclitaxel-carrying lipid has obvious brain tumor targeting function, and broad application prospect.

Venlafaxine, a novel third-generation antidepressant drug, has been described as a reference treatment for major depression, owing to its ability of inhibiting both noradrenalin and serotonin neuronal reuptake, and inhibiting dopamine reuptake slightly. However, its clinical application is hampered by a limited brain distribution. Glucosylation is an effective way to enhance the brain targeting ability of drugs, but the bidirectional transport of glucose transporter 1 (GLUT1) might decrease the concentrations of venlafaxine-glucose (V-G) in brain before the release of parent drug venlafaxine. To conquer this drawback of GLUT1, “lock-in” thiamine disulfide system (TDS) was introduced to modify the V-G conjugate. Both conjugates could release venlafaxine when incubated with the various buffers, mice plasma, and brain homogenate. The evaluation in vivo demonstrated that venlafaxine-TDS-glucose (V-TDS-G) had an improved targeting ability and significantly increased the level of venlafaxine in brain compared to the naked venlafaxine and V-G. The relative uptake efficiency (RE) and concentration efficiency (CE) were enhanced to 5.69 and 5.70 times higher than that of naked venlafaxine, respectively. The results of this study suggest that the conjugate strategy based on the glucose-TDS (G-TDS) is available to enhance the delivery of central nervous system (CNS) drugs into brain.

Background: Magnetic targeting, which utilizes a magnetic field to specifically deliver therapeutic agents to the targeted regions, can greatly improve the treatment efficiency. On the other hand, glucose-modified nanoparticles have also demonstrated good brain-targeting abilities. Fusion of both might further improve the brain targeting efficiency. Objective: To prepare, characterize and evaluate glucose-modified ibuprofen-loaded brain targeting magnetic nanoparticles (MNPs-APS-Glu). Methods: The magnetic nanoparticles MNPs-APS-Glu were designed and synthesized in order to effectively deliver ibuprofen to the brain through glucose transporter 1 (GLUT1) and an external magnetic field. The nanoparticles were characterized by FTIR, SEM and magnetic properties, and the drug loading capacity, cell cytotoxicity and drug release behavior of the new magnetic nanoparticles was studied. Results: The size of MNPs-APS-Glu was about 104.9 nm, and its drug loading capacity was up to 5%. Furthermore, these brain targeting magnetic nanoparticles maintained the magnetic property with a saturation magnetization level at ca. 32 emu/g and could release ibuprofen when incubated with various buffers, mice plasma and brain homogenate. Conclusions: The results indicated that the magnetic nanoparticles had potential to be a promising tool to selectively deliver drugs to the brain. This study may be conducive to the field of Central Nervous System (CNS) drugs delivery.

The treatment of glioma has become a great challenge because of the existence of brain barrier (BB). In order to develop an efficient brain targeting drug delivery system to greatly improve the brain permeability of anti-cancer drugs, a novel brain-targeted glucose-vitamin C (Glu-Vc) derivative was designed and synthesized as liposome ligand for preparing liposome to effectively deliver paclitaxel (PTX). The liposome was prepared and its particle size, zeta potential, encapsulation efficiency, release profile, stability, hemolysis and cytotoxicity were also characterized. What's more, the cellular uptake of CFPE-labeled Glu-Vc-Lip on GLUT1- and SVCT2-overexpressed C6 cells was 4.79-, 1.95-, 4.00- and 1.53-fold higher than that of Lip, Glu-Lip, Vc-Lip and Glu + Vc-Lip. Also, the Glu-Vc modified liposomes showed superior targeting ability in vivo evaluation compared with naked paclitaxel, non-coated, singly-modified and co-modified by physical blending liposomes. The relative uptake efficiency was enhanced by 7.53 fold to that of naked paclitaxel, while the concentration efficiency was up to 7.89 times. What's more, the Glu-Vc modified liposomes also displayed the maximum accumulation of DiD-loaded liposomes at tumor sites with the strongest fluorescence in the brain in vivo imaging. Our results suggest that chemical modification of liposomes with warheads of glucose and vitamin C represents a promising and efficient strategy for the development of brain-specific liposomes drug delivery system by utilizing the endogenous transportation mechanism of the warheads.

Empirical Karplus equations are very useful in the conformational analysis of flexible molecules, especially with regards to carbohydrates. The C(sp2)OCH dihedral angle of ester-functionalized carbohydrates, however, is not well described by widely used Karplus equations for COCH dihedral angles, because they are based on C(sp3)OCH data. Herein, we propose a three parameter Karplus equation of the form 3JCOCH = 5.18 cos2(θ?) -1.42 cos(θ?) + 1.05 on the basis of quantum mechanics computations for 6-O-acetyl-α/β-D-glucopyranose. The equation gives satisfactory agreement between experimentally determined 3JCH values and those back calculated from MD simulations using the GLYCAM06 forcefield for a set of acetylated glucoses and methyl glucuronate.

A pharmaceutical composition containing a compound of Formula (I) for treating an opioid receptor-associated condition. Also disclosed is a method for treating an opioid receptor-associated condition using such a compound. Further disclosed are two sets of thiazolidinone compounds of formula (I): (i) compounds each having an enantiomeric excess greater than 90% and (ii) compounds each being substituted with deuterium.

From the bark of Ladenbergia hexandra Klotzsch, ten triterpenoid glycosides were isolated along with five known compounds, and their structures were determined based on extensive NMR and mass spectroscopic, GC and HPLC analyses. Some triterpenoid glycosides contained 6-deoxy-D-allose or D-allose as a sugar moiety. The absolute stereochemical assignment of the sugars was determined by comparison with synthetic samples, as well as by GC and HPLC analysis.

Nanopesticides have been increasingly used in agriculture. To improve the uptake of the target organisms for nanopesticides, we designed a dual-ligand nanopesticide based on gold nanoparticles (Au NPs) as a carrier. Herein, the novel structure and properties of Au NPs conjugated with d-glucose (Glc) and rotenone (R) were characterized by UV-visible and FTIR spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential. The uptake and biodistribution of Glc-Au NPs, R-Au NPs, and Glc-Au NP-R were tested in tobacco BY-2 cells using flow cytometry, inductively coupled plasma optical emission spectroscopy (ICP-OES), confocal laser scanning microscopy (CLSM), and TEM. The cellular uptake of R-Au NP-Glc was increased by 1.8 folds as compared to that of R-Au NPs. Moreover, R-Au NPs-Glc could be actively transported into cells by hexose transporters and this uptake of the nanopesticides was an energy-dependent process. These results suggest that Glc is a promising ligand for the uptake and delivery of nanopesticides, and a well-designed system can enhance pesticidal bioavailability in agricultural scenarios.

The invention provides an alpha-galactosyl ceramide new isomer and its synthetic method. Configuration of sphingosine chain is changed to 4,5-cis double bond sphingosine chain. According to the invention, reaction steps are shortened, yield is raised, and aftertreatment and purification steps are omitted. The synthetic method can be used for total synthesis of similar glycosyl ceramide and satisfies wide range of development, research and application of different glycosyl ceramide.

A practical, facile method was developed for the preparation of 1,5-anhydroalditol via per-O-TMS-glycopyranosyl iodide with LiBH4. A series of 1,5-anhydroalditols were prepared in excellent yields (up to 92%) from unprotected carbohydrates within 2 days under mild conditions. In addition, multi-gram scale preparation of 1,5-anhydroglucitol (1,5-AG), a major polyol present in human serum, was developed using the same procedure without the need for chromatographic purification.

The SK3 potassium channel is involved in the development of bone metastasis and in the settlement of cancer cells in Ca2+-rich environments. Ohmline, which is a lactose-based glycero-ether lipid, is a lead compound that decreases SK3 channel activity and consequently limits the migration of SK3-expressing cells. Herein we report the synthesis of three new ohmline analogues in which the connection of the disaccharide moieties (1→6 versus 1→4) and the stereochemistry of the glycosyl linkage was studied. Compound 2 [3-(hexadecyloxy)-2-methoxypropyl-6-O-α-d-glucopyranosyl-β-d-galactopyranoside], which possesses an α-glucopyranosyl-(1→6)-β-galactopyranosyl moiety, was found to decrease SK3 current amplitude (70 % inhibition at 10 μm), displace SK3 protein outside caveolae, and decrease constitutive Ca2+entry (50 % inhibition at 300 nm) and SK3-dependent cell migration (30 % at 300 nm) at a level close to that of the benchmark compound ohmline. Compound 2, which decreases the activity of SK3 channel (but not SK2 channel), is a new drug candidate to reduce cancer cell migration and to prevent bone metastasis.

Trimethylsilyl (TMS) protecting group has been found to be very useful for the simultaneous protection of both the glycosyl donor- and the acceptor-substrates in oligosaccharide synthesis. Thus, while the per-O-trimethylsilylated glycosyl iodides served a

The invention discloses a novel glucose-based TDS modified brain-targeting prodrug with a locking function. The prodrug is of a structure shown in a general formula (I) (described in the specification) or pharmaceutically acceptable salt of hydrate of the structure, wherein X is -NH-(CH2)m-O-, -NH-(CH2)m-NH-, -C(O)-(CH2)m-NH-, -C(O)-(CH2)m-O-, -O-(CH2)m-O-, -O-(CH2)m-NH-; Y is -C(O)-(CH2)n-C(O)-; m represents 2-6, n represents 1-4; Drug is a drug acting on a central nervous system. A series of prodrugs provided by the invention, on the basis of glucose brain targeting, are added with a TDS part, so that the prodrugs have the locking function, brain targeting and center concentration of the drug can be improved, the curative effect of the drug is enhanced, and distribution of the drug in peripheral organs is reduced while toxic and side effects of the drug are reduced.

Four previously unreported steroidal saponins, trifasciatosides A-D (1-4), three pairs of previously undescribed steroidal saponins, trifasciatosides E-J (5a, b-7a, b) including acetylated ones, together with twelve known compounds were isolated from the n-butanol soluble fraction of the methanol extract of Sansevieria trifasciata. Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1H-NMR, 13C-NMR, 1H-1H correlated spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC), total correlated spectroscopy (TOCSY), nuclear Overhauser enhancement and exchange spectroscopy (NOESY), electrospray ionization-time of flight (ESI-TOF)-MS and chemical methods. Compounds 2, 4, and 7a, b exhibited moderate antiproliferative activity against HeLa cells.

The total synthesis of 4,5-cis unsaturated α-GalCer analogues was achieved, and their immune-response altering activity was assessed in vitro as well as in vivo in mice. Using glycosyl iodide as a glycosyl donor, construction of the sphingosine unit was shortened by four steps and single α-stereoselectivity was achieved in good yield (67%). With regard to the therapeutic use of α-GalCer, the novel analogues (1b and 1c) distinctly induced a Th1-biased cytokine response, avoiding induction of a contradictory response and overstimulation.

Four triterpenoid glycosides, possessing protobassic acid as common aglycon, together with 16 known compounds were isolated from the leaves of Planchonella obovata. They are 6β-hydroxy-conyzasaponin G (2), 3?-O-de-β-D-apiofuranosylisoarganin F (3), isoarganin F (4), and 6β-hydroxy-conyzasaponin N (5). The structures of these glycosides were elucidated based on spectroscopic analysis, in particular using 1D TOCSY to con.rm the 1H NMR assignment of each sugar residue. The absolute con.guration of each monosaccharide in the glycon part was determined by GC-FID. Compound 5, Mi-saponin A (8), and ursolic acid (10) showed moderate inhibitory activities against HL-60 leukemia cell line with the IC50 values of 16.88, 15.50, and 12.68 μM, respectively.

Background: Glucose-modified liposome showed a good brain-targeting ability. However, bidirectional transport of glucose transporter-1 (GLUT1) might reversely pump drugs out of the brain before releasing from the liposomes. Purpose: To overcome the bidirectional delivery of GLUT1, the thiamine disulfide system (TDS), with ability of "lock-in", was introduced and a new ligand, L-TDS-G, was designed and synthesized. Methods: The liposome was prepared and characterized for particle size, zeta potential, surface morphological property, encapsulation efficiency and release profile. C6 glioma cells were used as an in vitro model to access the cellular uptake abilities and cytotoxicity of the liposomes. Competition assay was performed to validate the GLUT1-mediated transport mechanism. Furthermore, the brain targeting abilities of the liposomes were evaluated through in vivo. Results: The preliminary evaluation in vivo demonstrated that L-TDS-G-coated liposome has an improved targeting ability and significantly increased the area under the concentration-time of docetaxel in brain as compared to naked docetaxel, non-coated and L-G coated liposomes. The relative uptake efficiency and concentration efficiency were enhanced by 3.82- and 4.99-fold compared to that of naked docetaxel, respectively. Conclusion: The results of this study indicated that L-TDS-G-coated liposome is a promising drug delivery system to enhance the brain concentrations of chemotherapeutic agents.

Allium cepa L. is one of the most widely cultivated and used plants. In addition to its bulb (onion), which is used as food in many cultures, the seeds of A. cepa L. are used as a traditional herbal medicine by the Uygur nationality in China to treat diarrhea and promote blood flow. In a bioactivity-screening, the ethanol extract of seeds of A. cepa L. showed inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) enzyme, with 81.1% inhibition. Phytochemical investigation of the ethanol extract of red onion (Allium cepa L.) seeds led to the isolation of eight new furostanol saponins, named ceparosides E-L (1-8). Their structures were established using 1D and 2D NMR spectroscopy, mass spectrometry and chemical methods. Compounds 1-8 were screened for inhibitory effects on the PTP1B enzyme and cytotoxic activity against five human cells, including HCT-8, Bel-7402, BGC-823, A549 and A2780, but all were found to be inactive.

Living organisms employ glycans as recognition elements because of their large structural information density. Well-defined sugar structures are needed to fully understand and take advantage of glycan functions, but sufficient quantities of these compounds cannot be readily obtained from natural sources and have to be synthesized. Among the bottlenecks in the chemical synthesis of complex glycans is the preparation of suitably protected monosaccharide building blocks. Thus, easy, rapid, and efficient methods for building-block acquisition are desirable. Herein, we describe routes directly starting from the free sugars toward notable monosaccharide derivatives through microwave-assisted one-pot synthesis. The procedure followed the in situ generation of per-O-trimethylsilylated monosaccharide intermediates, which provided 1,6-anhydrosugars or thioglycosides upon treatment with either trimethylsilyl trifluoromethanesulfonate or trimethyl(4-methylphenylthio)silane and ZnI2, respectively, under microwave irradiation. We successfully extended the methodology to regioselective protecting group installation and manipulation toward a number of thioglucosides and the glycosylation of persilylated derivatives, all of which were conducted in a single vessel. These developed approaches open the possibility for generating arrays of suitably protected building blocks for oligosaccharide assembly in a short period with minimal number of purification stages.

Biologically essential carbohydrate 6-phosphates, especially trehalose 6-phosphate, can be synthesized easily in excellent overall yields in 2 steps involving minimum protecting group manipulations. We can cleave the diphenylphosphate group for further synthetic objectives.

Provided herein are sphingolipid compounds that are useful for activating natural killer T cells. Also provided are methods for treating or preventing a disease or disorder that is treatable by activating the immune system by stimulating natural killer T cells. The compounds are therefore useful for treating or reducing the likelihood of occurrence of an immune diseases and disorders, such as autoimmune diseases or disorders. The compounds may also be used for treating or reducing the likelihood of occurrence of a microbial infection or for treating or reducing the likelihood of occurrence of a cancer in a subject by administering the sphingolipid compounds described herein.

The recent discoveries of the involvement of SK3 channel in some cell motility mechanisms occurring in cancer disease have opened up the way to the synthesis of inhibitors that could reduce metastasis formation. On the basis of our recent previous works showing that both lactose-glycero-ether lipid (Ohmline) and some phosphate analogues (GPGEL) were efficient compounds to modulate SK3 channel activity, the present study, which found its inspiration in the structure of the natural glycolipid DiGalactosylDiacylGlycerol (DGDG), reports the incorporation of a digalactosyl moiety (α-galactopyranosyl- (1→6)-β-galactopyranosyl-) as the polar head of a glycero ether lipid. For the construction of the digalactosyl fragment, two synthetic approaches were compared. The standard strategy which is based on the use of the benzyl protecting group to produce 1→6 disaccharide unit, was compared with a second method that made use of the trimethylsilyl moiety as a protecting group. This second strategy, which is applied for the first time to the synthesis of (1→6)-disaccharide unit, presents a net advantage in terms of efficacy (better global yield) and cost. Finally, compound 16, which is characterized by a (1→6) DiGalactosyl unit (DG) as the polar head of the amphiphilic structure, was tested as a modulator of the SK3 channel activity. Patch-clamp experiments have shown that compound 16 reduced SK3 currents (-28.2 ± 2.0% at 5 μM) and cell migration assays performed at 300 nM have shown a reduction of cell migration (SK3 + HEK293T) by 19.6 ± 2.7%. The Royal Society of Chemistry 2013.

An uncatalysed silylation of phenols, regardless on the aggregate state and nature of the substituents with 0.55 equiv of HMDS under solvent-free reaction conditions (SFRC) at room temperature is reported. Sterically hindered phenols, carbohydrates and most of the alcohols additionally required a catalytic amount (up to 2 mol %) of iodine. The reaction protocol is very simple; obtaining a pure product, particularly of uncatalysed reactions, was frequently a completely solvent-free process.

Bioactivity-guided separation of the aqueous methanolic extract of Yucca desmettiana leaves, which in a preliminary screening exhibited significant molluscicidal activity, led to the isolation and structure elucidation of two new steroidal saponins (1 and 2). The structures of desmettianosides A and B, identified as bisdesmosidic furostanol glycosides with six and five sugar units, respectively, were established by detailed spectroscopic analyses of their NMR and MS data. Compounds 1 and 2 exhibited high molluscicidal activity against Biomphalaria alexandrina snails with LC100 values of 6 and 11 mg/L, respectively.

A simple two-step procedure yielding peracetylated furanoses directly from free aldoses was implemented. Key steps of the method are (i) highly selective formation of per-O-(tert-butyldimethylsilyl)furanoses and (ii) their clean conversion into acetyl ones without isomerization. This approach was easily applied to galactose and structurally related carbohydrates such as arabinose, fucose, methyl galacturonate and N-acetylgalactosamine to give the corresponding peracetylated targets. The success of this procedure relied on the control of at least three parameters: (i) the tautomeric equilibrium of the starting unprotected oses, (ii) the steric hindrance of both targeted furanoses and silylating agent, and finally, (iii) the reactivity of each soft nucleophile during the protecting group interconversion.

Anticancer vaccine: Antigen 2 made out of a tripeptide of β-D-Galp-(1→3)-CH2-α-D-GalNAc-O-Ser and conjugated with keyhole limpet hemocyanin (KLH) protein induced an early and strong immune response (IgG antibodies) in mice. Antigen 3 made out o

A highly efficient TMSOTf-catalyzed HMDS silylation of sugars, which can easily be integrated with subsequent reactions in one-pot fashion, has been developed. Its usefulness was demonstrated by applications to streamlined regioselective one-pot protection and nonenzymatic acetylation of unprotected sugars. Monosaccharide and trehalose building blocks with orthogonally well-differentiated hydroxy groups were efficiently prepared starting with free sugars in one-pot fashion without the need for prior per-O-silylation. Regioselectively protected and acetylated building blocks were prepared directly from unprotected sugars in a one-pot manner involving up to five TMSOTf-catalyzed reactions, including a new TMSOTf-catalyzed silylation of carbohydrates. Copyright

Four new polyphenols namely excoecariphenols A-D (1-4) were isolated from the Chinese mangrove plant Excoecaria agallocha L. together with 23 known phenolic compounds. The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses including IR, MS, NMR, and CD data. Excoecariphenols A and B presented as the unusual flavane-based 1-thioglycosides. Part of the isolated polyphenols were tested against hepatitis C NS3-4A protease and HCV RNA in huh 7.5 cells. Excoecariphenol D, corilagin, geraniin, and chebulagic acid showed potential inhibition toward HCV NS3-4A protease with IC50 values in a range of 3.45-9.03 μM, while excoecariphenol D and corilagin inhibited HCV RNA in huh 7.5 cells significantly. A primary structure-activity relationship (SAR) is discussed.

Fusaroside (1), a unique trehalose-containing glycolipid composed of the 4-hydroxyl group of a trehalose unit attached to the carboxylic carbon of a long-chain fatty acid, was isolated from the organic extract of fermentation broths of an endophytic fungus, Fusarium sp. LN-11 isolated from the leaves of Melia azedarach. Six known compounds, phalluside (2), (9R*,10R*,7E)- 6, 9,10-trihydroxyoctadec-7-enoic acid (3), porrigenic acid (4), (9Z)-2,3-dihydroxypropyl octadeca-9-enoate (5), cerevisterol (6) and ergokonin B (7), were also isolated from this fungus. The glycolipid contains a rare branched long-chain fatty acid (C20:4) with a conjugated diene moiety and a conjugated ketone moiety. The structure of the new compound 1 was elucidated by spectroscopic methods (1D and 2D NMR experiments, MS) and chemical degradations. The metabolites 1-5 were shown to have moderate to weak active against the brine shrimp larvae. To our knowledge, this is the first report of isolation of the first representative of a new family of glycolipids from natural sources.

This study was aimed at synthesizing and evaluating a prednisolone-glucose derivative conjugate (PDG) that was expected to increase renal biodistribution without affecting pharmacological action and to decrease the systemic side effects of prednisolone. T

Different derivatization procedures were assayed to simultaneously analyse iminosugars such as deoxynojirimycin (DNJ) or fagomine and other carbohydrates of low molecular weight by gas chromatography coupled to mass spectrometry (GC-MS) in Morus sp. Both oximation + trimethylsilylation and oximation + acetylation allowed the separation of target compounds, whereas trimethylsilyl (TMS) and acetylated derivatives showed several coelutions. Nevertheless, oximation + acetylation were discarded for giving inaccurate results for ketoses due to their incomplete derivatization. Different conditions for the conversion into trimethylsilyl oximes (TMSO) were assayed, the best results being achieved using hexamethyldisilazane with trifluoroacetic acid as silylation agent. Contents of iminosugars (DNJ, fagomine and pipecolic acid derivatives) and other carbohydrates such as mono and disaccharides, myo-inositol and galactinol isomers in mulberry extracts (fruits, leaves and branches) were determined by GC-MS using the TMSO procedure.

A glycolipid, 2-acetyl-1-{3-[3,4-di-O-acetyl-β-d-glucopyranosyl-(1 → 3)-2-O-acetyl-α-l-rhamnopyranosyloxy]octadecanoyl}-sn-glycerol (1) and a dammarane triterpene, (2α,20S)-2,20-dihydroxydammar-24-en-3-one (2), along with known (20S)-20-hydroxydammar-24-en-3-one (3), were isolated from the exudates of the glandular trichome-like secretory organs in the young stipules and leaves of Cerasus yedoensis (Rosaceae).

Glucosyl derivates exhibited favorable distribution to the brain. However, bidirectional transport of glucose transporter 1 might decrease concentrations of the prodrugs in brain before the release of parent drugs. To overcome this defect, glucosyl thiamine disulfide prodrugs 1a-1c incorporating naproxen were designed and synthesized. Furthermore, prodrug 2 and 3 were also prepared as control. The favorable physicochemical properties of these prodrugs were verified by stability and metabolism studies. Results from the in vivo distribution study indicated that 1a-1c, and 1b in particular, significantly increased the level of naproxen in brain when compared to 2 and 3. The study suggested glucosyl thiamine disulfide was a promising carrier to enhance the brain bioavailability of central nervous system active drugs.