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Most lung cancer bone metastasis are characterized by osteolytic destruction and osteoblastic activity is significantly decreased, suggesting that hypoxia may play a critical role in the process, but the underlying mechanisms remain unknown. Semaphorin 4D (Sema4D) is a recently discovered osteogenic inhibitory factor that is expressed at high levels in lung cancers. Here, CoCl2-induced hypoxia significantly enhanced the inhibitory effect of lung cancer cell conditioned media on osteoblast differentiation by inducing the expression and secretion of Sema4D in a HIF-1α- but not HIF-2α-dependent manner. Moreover, HIF-1α directly regulated Sema4D expression by binding to bases 1171 to 798 in the Sema4D promoter. Furthermore, hypoxia increased Sema4D secretion by upregulating a disintegrin and metalloproteinase 17 (ADAM17) expression in lung cancer in a HIF-1α-dependent manner. In bone metastasis samples from 49 patients with lung cancer, Sema4D and ADAM17 expression significantly correlated with HIF-1α expression and strongly correlated with a poor differentiation status and osteolytic bone destruction. These results provide the first evidence that HIF-1α-induced Sema4D expression and secretion play important roles in lung cancer osteolytic bone metastasis by inhibiting osteoblast differentiation, thereby providing potential strategies for the treatment of bone metastasis via targeting osteoblasts.

Malignant pleural mesothelioma (MPM) is a type of cancer originating from the pleura with high aggressiveness and poor prognosis. A timely diagnosis is crucial to improve its prognosis. Laboratory biomarkers have significant advantages of reduced invasiveness, low cost, and are observer‐independent, and therefore represent a promising diagnostic tool for MPM. MicroRNA is a family of non‐coding RNA that regulates gene expression at the post‐transcriptional level. Accumulated studies showed that microRNA, either in tissue, circulating, and body fluid, has potential diagnostic value for various disorders. Here, we reviewed the diagnostic value of microRNA for MPM., Malignant pleural mesothelioma (MPM) is a type of cancer originating from the pleura with high aggressiveness and poor prognosis, Laboratory biomarkers have significant advantages of reduced invasiveness, low cost, and are observer‐independent, and therefore represent a promising diagnostic tool for MPM. Here, we reviewed the diagnostic value of microRNA for MPM.

Background: Whether routine urinary analysis has a net benefit for urinary tract infection (UTI) screening is unclear. Methods: Using the laboratory information system (LIS), we retrospectively extracted the data of urine culture and routine analysis between January 2017 and April 2017. Receiver operating characteristic (ROC) curve, logistic regression model, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to estimate the screening performance of routine urinary analysis. Decision curve analysis (DCA) was used to estimate the net benefit of routine urinary analysis. Results: A total of 927 specimens with 156 UTIs were included in the present study. The area under ROC curves (AUCs) of white blood cells (WBCs) and bacteria were 0.729 and 0.836, respectively. The logistic regression model incorporating WBCs, bacteria and nitrite together had an AUC of 0.851, which is significantly higher than that of WBCs. NRI and IDI analyses also indicated that WBCs, bacteria and nitrite, when used together, had better a screening performance than each single test alone. DCA revealed that 0.08 net benefit can be obtained for bacteria and the model, while the net benefit of WBCs is limited. Conclusions: WBCs, bacteria and nitrite, when used together, can significantly improve the efficiency for UTI screening. Bacteria and the model incorporating WBCs, bacteria and nitrite have a net benefit in UTI screening, while the net benefit of WBCs, when used alone, is limited.

Heparin-binding hemagglutinin (HBHA) is a 199 amino acid virulence factor at the envelope of Mycobacterium tuberculosis that contributes to latent tuberculosis. The binding of HBHA to respiratory epithelial cells, which leads to extrapulmonary dissemination of the pathogen, is mediated by cell-surface heparan sulfate (HS). We report the structural characterization of the HBHA/HS complex by NMR spectroscopy. To develop a model for the molecular recognition, the first chemically synthesized uniformly 13 C- and 15 N-labeled HS octasaccharide and a uniformly 13 C- and 15 N-labeled form of HBHA were prepared. Residues 180-195 at the C-terminal region of HBHA show large chemical shift perturbation upon association with the octasaccharide. Molecular dynamics simulations conforming to the multidimensional NMR data revealed key electrostatic and even hydrophobic interactions between the binding partners that may aid in the development of agents targeting the binding event.

Cancer treatment with antibodies (Abs) is one of the most successful therapeutic strategies for obtaining high selectivity. In this study, α-gal-Ab conjugates were developed that dramatically increased cellular cytotoxicity by recruiting natural Abs through the interaction between α-gal and anti-gal Abs. The potency of the α-gal-Ab conjugates depended on the amount of α-gal conjugated to the antibody: the larger the amount of α-gal introduced, the higher the level of cytotoxicity observed. The conjugation of antibodies with an α-gal dendrimer allowed the introduction of large amounts of α-gal to the Ab, without loss of affinity for the target cell. The method described here will enable the re-development of Abs to improve their potency.

New Findings What is the central question of this study? Our previous study demonstrates that elevated orexin 2 receptor (OX2R) activity within the rostral ventrolateral medulla (RVLM) contributes to hypertension in spontaneously hypertensive rats (SHRs), and a lower OX2R protein level was detected in their RVLM. The present study aims to explore the mechanisms underlying elevated orexinergic activity in the RVLM of SHRs, compared with their normotensive counterparts, Wistar-Kyoto rats. What is the main finding and its importance? Increased orexinergic input into the RVLM and enhanced OX2R responsiveness in the RVLM, which was mainly mediated by augmented OX2R–neuronal nitric oxide synthase signalling, may underlie the elevated OX2R activity within the RVLM of SHRs. Abstract Our previous study showed that elevated orexin 2 receptor (OX2R) activity within the rostral ventrolateral medulla (RVLM) contributes to hypertension in spontaneously hypertensive rats (SHRs). Herein, we investigated the mechanism(s) underlying the elevated OX2R activity. The following results were found. (i) More hypothalamic orexin A-immunoreactive (OXA-IR) cells existed in SHRs than in Wistar-Kyoto (WKY) rats at either 4 (2217 ± 43 versus 1809 ± 69) or 16 weeks of age (1829 ± 59 versus 1230 ± 84). The number of OXA-IR cells that project to the RVLM was higher in 16-week-old SHRs than in WKY rats (91 ± 11 versus 52 ± 11). (ii) Higher numbers of OXA-IR and RVLM-projecting OXA-IR cells were found in the dorsomedial and perifornical hypothalamus of 16-week-old SHRs. (iii) Spontaneously hypertensive rats had higher levels of orexin A and B in the hypothalamus and higher levels of orexin A in the RVLM than did WKY rats. (iv) Unilateral intra-RVLM application of OX2R agonist, orexin A or [Ala11,d-Leu15]-orexin B (50 pmol) induced a larger pressor response in SHRs than in WKY rats. (v) Intra-RVLM pretreatment with a neuronal nitric oxide synthase (NOS) inhibitor, 7-nitro-indazole (2.5 pmol), or a soluble guanylate cyclase inhibitor, methylene blue (250 pmol), reducedthe intra-RVLM [Ala11,d-Leu15]-orexin B-induced pressor response in both WKY rats and SHRs. In contrast, an inducible NOS inhibitor, aminoguanidine (100 pmol), was ineffective. (vi) Neuronal NOS was co-expressed with OX2R in RVLM neurons. In conclusion, increased orexinergic input and enhanced OX2R–neuronal NOS signalling may underlie elevated OX2R activity in the RVLM and contribute to the pathophysiology of hypertension in SHRs.

Fondaparinux, a synthetic pentasaccharide based on the heparin antithrombin-binding domain, is an approved clinical anticoagulant. Although it is a better and safer alternative to pharmaceutical heparins in many cases, its high cost, which results from the difficult and tedious synthesis, is a deterrent for its widespread use. The chemical synthesis of fondaparinux was achieved in an efficient and concise manner from commercially available D-glucosamine, diacetone α-D-glucose, and penta-O-acetyl-D-glucose. The method involves suitably functionalized building blocks that are readily accessible and employs shared intermediates and a series of one-pot reactions that considerably reduce the synthetic effort and improve the yield.

Heparan sulfate (HS) is a linear sulfated polysaccharide that mediates protein activities at the cell-extracellular interface. Its interactions with proteins depend on the complex patterns of sulfonations and sugar residues. Previously, we synthesized all 48 potential disaccharides found in HS and used them for affinity screening and X-ray structural analysis with fibroblast growth factor-1 (FGF1). Herein, we evaluated the affinities of the same sugars against FGF2 and determined the crystal structures of FGF2 in complex with three disaccharides carrying N-sulfonated glucosamine and 2-O-sulfonated iduronic acid as basic backbones. The crystal structures show that water molecules mediate different interactions between the 3-O-sulfonate group and Lys125. Moreover, the 6-O-sulfonate group forms intermolecular interactions with another FGF2 unit apart from the main binding site. These findings suggest that the water-mediated interactions and the intermolecular interactions influence the binding affinity of different disaccharides with FGF2, correlating with their respective dissociation constants in solution.

Orexins can raise arterial pressure and sympathetic activity and are involved in tonic and phasic control of cardiovascular homeostasis. We hypothesized that elevated central orexinergic activity contributes to the maintenance of hypertension in spontaneously hypertensive rats (SHRs). We examined this hypothesis by suppressing central orexinergic activity in SHRs and Wistar-Kyoto rats (WKYs) with specific antagonists or antibodies against orexin 1 (OX1R) and 2 receptors (OX2R). Intracerebroventricular administration of an OX1R antagonist, SB-334867 (30 and 100 nmol), induced no significant change in mean arterial pressure (MAP) and heart rate (HR) in SHRs and WKYs except that at 100 nmol it reduced HR in WKYs. In contrast, an OX2R antagonist, TCS-OX2-29 (3-30 nmol) induced long-lasting reductions of MAP and HR in SHRs (21 ± 3 mmHg and 22 ± 2 beats min(-1) at 30 nmol), but not in WKYs. Intracerebroventricular anti-OX2R IgG, but not anti-OX1R IgG or non-immune goat IgG, significantly lowered MAP and HR in SHRs. None of the three IgGs affected MAP or HR in WKYs. The OX2R protein level in the rostral ventrolateral medulla (RVLM) was lower in SHRs than in WKYs, whereas no differences were found between SHRs and WKYs in the paraventricular hypothalamic nucleus, dorsomedial-perifornical hypothalamic area or caudal nucleus tractus solitarii. The OX1R protein levels in these four regions did not differ between SHRs and WKYs. Injection of TCS-OX2-29 (50 pmol) into the RVLM produced a larger reduction of MAP in SHRs than in WKYs. We conclude that elevated OX2R-mediated activity in the brain, especially in the RVLM, may contribute to hypertension in SHRs.

Glycosaminoglycans such as heparan sulfate (HS) are major components of the cell surface and extracellular matrix (ECM) of all multicellular animals, connecting cells to each other as well as to their environment. The ECM must, therefore, both sense and accommodate changes to external conditions. Heparin, a model compound for HS, responds to increased temperatures, involving changes in the populations of conformational states with implications for the binding of HS to proteins, cations and, potentially, for its activity. A fully 13C and 15N labelled model octasasccharide; D-GlcNS6S α(1-4) L-IdoA2S [α(1-4) D-GlcNS6S α(1-4) L-IdoA2S]2 α(1-4) D-GlcNS6S α(1-4) L-IdoA1,6an, was studied by 1H, 13C and 15N NMR, revealing complex changes in chemical shifts and conformation, over temperatures (280-305 K), comfortably within the range relevant to terrestrial biology. These complex conformational changes indicated an interaction between the carboxylate group of L-iduronate and D-glucosamine residues that was susceptible to temperature changes in this range, while the well-documented hydrogen bond between the N-sulfamido group of glucosamine and the hydroxyl group at position-3 of iduronate remained intact. Unexpectedly, despite the presence of similar thermally-induced conformational changes in a heparin octasaccharide fraction in the sodium ion form, its subsequent binding to calcium ions and their resulting conformation was stringently maintained, as judged by comparisons of 1H NMR chemical shifts.

Kohlenhydrate spielen eine wichtige Rolle bei biologischen Vorgangen. Das Fortschrittstempo der Kohlenhydratforschung ist jedoch relativ langsam, was unter anderem mit der Komplexitat der Kohlenhydratstrukturen und dem Fehlen allgemein anwendbarer Synthesemethoden und Verfahren zur Untersuchung dieser Klasse von Biomolekulen zusammenhangt. Jungste Fortschritte in der Synthese haben ergeben, dass viele dieser Probleme umgangen werden konnen. In diesem Aufsatz beschreiben wir die Methoden, die entwickelt wurden, um mit den Herausforderungen kohlenhydratvermittelter biologischer Vorgange umzugehen. Besonderes Augenmerk wird dabei auf die Entwicklung der automatisierten Synthese von Oligosacchariden gerichtet. Daruber hinaus werden auch Kohlenhydrat-Mikroarrays und Impfstoffe auf Kohlenhydratbasis behandelt.

Few studies calculating burden of disease (BOD) have been carried out in China. Disability-adjusted life years (DALY) is one of the useful methods used to estimate BOD. This study aims to use DALY for evaluating BOD and to provide useful information for health planning for residents in Shilin Yi Nationality Autonomous County (Shilin County) of Yunnan Province, China.Methods developed for the Global Burden of Disease (GBD) Study by the World Bank and World Health Organization (WHO) were adapted and applied to Shilin County population health data. DALY rate per 1,000 was calculated from medical death certificates in 2003 in Shilin County. The geographic coordinates of towns or townships were determined using the geocode function of R2.3.1 geographical information system (GIS) software.Respiratory diseases were by far the leading cause of years of life lost (YLL) in both males and females. The four other leading causes of YLL in descending order were: unintentional injuries, cardiovascular diseases, intentional injuries, and malignant neoplasms. However, the five leading causes of years lived with disability (YLD) were, in descending order: neuropsychiatric conditions, intentional injuries, respiratory diseases, unintentional injuries, and cardiovascular diseases. The leading cause of total disease burden (DALY) was neuropsychiatric conditions. Townships of Muzhuqing, Xijiekou, and Weize were the areas with most serious disease burden in Shilin County.Prevention and treatment of neuropsychiatric conditions and respiratory diseases for both females and males should be enhanced in Shilin County, so as to decrease injury. More preventive interventions for noninfectious chronic diseases should be emphasized in remote townships.

In current health examination setting, people frequently undergo heart rate variability (HRV) analysis and colonoscopy on the same day. However, it remains unclear whether the bowel preparation before colonoscopy affects HRV. This study aimed to evaluate the association between HRV and bowel preparation. We conducted a cross-sectional observational study of 1755 people from January 2012 to December 2013 in Taipei, Taiwan. The participants, aged 45 to 65 years, received health examinations that included a physical examination, blood tests, and an HRV analysis. Among these people, 1099 additionally received a colonoscopy on the same day and underwent bowel preparation 1 day before the colonoscopy. The association between HRV and bowel preparation was derived by a multivariable linear regression with adjusted confounding factors. Bowel preparation was associated with a lower standard deviation of the normal-to-normal intervals (SDNN), the root mean square of the successive differences (RMSSD), low-frequency power (LF), and high-frequency power (HF) (all P

In recent years, there has been rapid expansion of glycan synthesis, fueled by the recognition that the structural complexity of sugars translates to a myriad of biological functions. Such chemical syntheses involve many challenges, mostly due to the regio- and stereochemical aspects of glycosidic bond formation. One-pot strategies were developed to assist in attaining faster and more economical access to the glycan constructs. In this front, achievements in protecting group manipulation, glycosylation, and combinations of these have been reported. Protecting group manipulations in one pot take advantage of the reaction compatibility of commonly used transformations, many of which occur in high regioselectivity. Sequential glycosylations, on the other hand, rely on leaving group orthogonalities and reactivity tuning, as well as the preactivation technique. Altogether, these approaches offer attractive means to the much needed glycan structures and, consequently, help usher in advances in glycoscience.

(13)C NMR solid-state structural analysis of the anomeric center in carbohydrates was performed on six monosaccharides: glucose (Glc), mannose (Man), galactose (Gal), galactosamine hydrochloride (GalN), glucosamine hydrochloride (GlcN), and N-acetyl-glucosamine (GlcNAc). In the 1D (13)C cross-polarization/magic-angle spinning (CP/MAS) spectrum, the anomeric center C-1 of these carbohydrates revealed two well resolved resonances shifted by 3-5ppm, which were readily assigned to the anomeric alpha and beta forms. From this experiment, we also extracted the (13)C chemical shift anisotropy (CSA) tensor elements of the two forms from their spinning sideband intensities, respectively. It was found out that the chemical shift tensor for the alpha anomer was more axially symmetrical than that of the beta form. A strong linear correlation was obtained when the ratio of the axial asymmetry of the (13)C chemical shift tensors of the two anomeric forms was plotted in a semilogarithmic plot against the relative population of the two anomers. Finally, we applied REDOR spectroscopy to discern whether or not there were any differences in the sugar ring conformation between the anomers. Identical two-bond distances of 2.57A (2.48A) were deduced for both the alpha and beta forms in GlcNAc (GlcN), suggesting that the two anomers have essentially identical sugar ring scaffolds in these sugars. In light of these REDOR distance measurements and the strong correlation observed between the ratio of the axial asymmetry parameters of the (13)C chemical shift tensors and the relative population between the two anomeric forms, we concluded that the anomeric effect arises principally from interaction of the electron charge clouds between the C-1-O-5 and the C-1-O-1 bonds in these monosaccharides.

[reaction: see text] A coupling of 2-O-arylmethylated D-glucose-derived thioglycosides with various alcohols in the presence of DMTST as an activator is described. The requisite glycosyl donors are efficiently prepared by one-pot procedures. When the aryl groups are phenyl, p-methoxyphenyl, 1-naphthyl, and 2-naphthyl groups, a mixture of alpha- and beta-anomeric O-glycosides is obtained under the conditions, whereas when the aryl group is the 9-anthracenyl group, a highly stereoselective formation of the unusual C-glycosides in good yields via neighboring group participation of the 9-anthracenylmethyl group followed by coupling with a variety of alcohols is observed. Three new chiral centers including a quaternary carbon are created in one single step.

Protein tyrosine kinase 7 (PTK7) has been studied in various tumors, but its role in prostate cancer remains unknown. This study is aimed to investigate the prognostic and predictive significance of PTK7 in patients with prostate cancer. PTK7 expression was evaluated by real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis in 20 pairs of benign prostatic hyperplasia specimens and prostate cancer specimens. Then, we examined the immunohistochemical expression of PTK7 in 180 prostate cancer specimens and evaluated its clinical significances. Elevated PTK7 expression was significantly associated with lymph node metastases, seminal vesicle invasion, prostate cancer stage, the higher preoperative prostate-specific antigen, the higher Gleason score, angiolymphatic invasion, and biochemical recurrence. The results revealed that the overexpression of PTK7 in prostate cancer was an independent prognostic factor for poor overall survival and biochemical recurrence-free survival. The present data provide evidence that PTK7 predicts lymph node metastasis and poor overall survival and biochemical recurrence-free survival, highlighting its potential function as a therapeutic target for prostate cancer.

The TmsOTf-catalyzed reaction of tetrasilylated glucoside (I) with benzaldehyde leads to an intermediate benzylidene acetal diol, which is converted into triols (III) and (IV) by a reductive ring opening (11 further examples for the one-pot protection).

The cell envelope of mycobacterial species, which include the deadly Mycobacterium tuberculosis, carries unique glycan structures that are crucial for infection and bacterial survival. Notable among these glycans are the structurally-related phosphatidylinositol mannosides (PIMs), lipomannan, and lipoarabinomannan. The immunoactivities of these structures attracted considerable attention from synthetic chemists and biologists alike, who are keen on evaluating vaccine or adjuvant properties. Moreover, PIMs are interesting synthetic targets because of the regio- and stereoselective considerations in generating the inositol and mannosyl cores. In this paper, we summarize the recent efforts in the chemical synthesis of PIMs as well as their analogues. Particular emphasis is given on the challenges associated with the preparation of the chiral myo-inositol derivatives, the regioselective installation of mannosyl residues, and phosphatidylation strategies. The results of the bioevaluation of selected compounds are also briefly described.

Carbohydrates either conjugated or as free entities are major players in numerous biological processes. The desire to comprehend the nature of their functions and further develop therapeutic and diagnostic applications has fuelled the recent upsurge in the glycoscience field. Mainly accessed through chemical synthesis, homogeneous and well-defined sugar constructs are on high demand for structure–activity evaluation. Although the D-sugars, particularly the D-hexoses, have dominated the carbohydrate landscape, L-hexoses also attracted attention because they are known components of important polysaccharides, antibiotics, and other natural products. Nonetheless, the L-hexose-based materials needed for making building blocks for sugar assemblies are rare and are usually expensive if commercially available. Thus, intense efforts were focused on the development of innovative and reliable methods for the acquisition of L-hexoses and their derivatives. This review outlines several efficient and cost-effective routes for the chemical syntheses of L-hexoses, particularly focusing on approaches that utilize commercially abundant sugars as starting materials. A sampling of the applications of the generated L-hexoses in preparing biologically relevant compounds is also provided.

Carbohydrates have been shown to play important roles in biological processes. The pace of development in carbohydrate research is, however, relatively slow due to the problems associated with the complexity of carbohydrate structures and the lack of general synthetic methods and tools available for the study of this class of biomolecules. Recent advances in synthesis have demonstrated that many of these problems can be circumvented. In this Review, we describe the methods developed to tackle the problems of carbohydrate-mediated biological processes, with particular focus on the issue related to the development of the automated synthesis of oligosaccharides. Further applications of carbohydrate microarrays and vaccines to human diseases are also highlighted.

Glycosylations employing 2-allylphenyl glycoside, a new type of stable glycosyl donor, were optimized and explored with a variety of acceptors promoted by ICl/AgOTf. The utility of the protocol was further demonstrated with an efficient synthesis of the disaccharide fragment of bleomycins.

Deciphering the roles and structure-activity relationships of carbohydrates in biological processes requires access to sugar molecules of confirmed structure and high purity. Chemical synthesis is one of the best ways to obtain such access. However, the synthesis of carbohydrates has long been impeded by two major challenges--the regioselective protection of the polyol moiety of each monosaccharide building block and the stereoselective glycosylation to produce oligosaccharides of desired length. Here, we review the development of the first regioselective protection-glycosylation and a revolutionary regioselective combinatorial one-pot protection of monosaccharides that can be used to differentiate the various hydroxy groups of monosaccharides with a vast array of orthogonal protective groups in one-pot procedures.

A highly regioselective acylation of myo-inositol 1,3,5-orthoformate at the 4-O/6-O positions is catalyzed by various metal trifluoromethanesulfonates, giving excellent yields; an asymmetric example using (−)-camphanic anhydride is described here.

Glycosyl chlorides with acid-labile protecting groups were prepared from their corresponding alcohols under basic conditions in good yields. The synthesis of a 1,6-C-linked disaccharide was carried out via reaction of a glycosyl chloride with an aldehyde in the presence of samarium(II) diiodide.

An improved method for the synthesis of azides is described. Diazo transfer from trifly azide effectively with Cu++, Ni++ or Zn++ as a catalyst. The process is amenable to scaleup, can be carried out using commercially available reagents and does not require anhydrous conditions. When metals are scavenged from the reaction, the rate drops by many orders of magnitude.

A one-pot synthesis of 1-allyl- and 1-allenyl-6-O-acetyl-2,3,4-tri-O-benzyl-α-D-glycosides from the corresponding methyl per-benzyl-α-D-glycosides and allyl trimethylsilane or propargyl trimethylsilane in the presence of trimethylsilyl trifluoro-methanesulfonate followed by addition of acetic anhydride in good yields was described.

Synthesis of optically active a-alkyl and a-arylthioglycolic acids from thioglycolic acid could be achieved by employing (1R)-(+)-camphor as the template. Asymmetric synthesis of D-daunosamine from thioglycolic acid through chiral 1,3-0xathiolan-5-one 5a was achieved in six synthetic steps. Asymmetric synthesis of optically active 1,2-diols from alkynes through camphor derived chiral allenes is described. Preparation and synthetic application of chiral three carbon building blocks from glycerol could be achieved by employing ( 18-(+)-NJV-diisopropyl- 10-camphorsulfonamide 2 as chiral template. Synthesis of an enantiomerically pure biologically active molecule requires an enantiomerically pure starting material. They were normally obtained or derived from naturally occurring source.(ref. 1) It is a challenge for an organic chemist to devise a method to convert an achiral compound to a chiral compound by simple procedure through easy operations. We found that a chiral ketone with a rigid three-dimensional structure could provide an asymmetric environment for the enantioselective synthesis of organic molecules. Asymmetric synthesis employing (1R)-(+)-camphor 1 or (lS)-(+)-NJV- diisopropyl- 10-camphorsulfonamide 2 as a chiral template in the syntheses of optically active molecules from prochiral compounds could be achieved with high enantioselectivity.

This paper describes a high-yield, one-step synthesis of 2-deoxy-2-fluoro sugars and their glycosides from glycals using the available electrophilic fluorination reagent 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor) in the presence of a nucleophile. The method was further expanded to the synthesis of glycosyl fluorides and glycosides from anomeric hydroxy or thioglycoside derivatives.

A new strategy, utilizing IR and mass spectrometry, has been developed to design appropriate reagents and reaction conditions for enantioselective enzymatic protection of amines with readily removable protecting groups.

Two convenient routes for the synthesis of l -altrose and l -mannose from 1,2:3,5-di- O -isopropylidene-β- l -idofuranose in four and six steps via the stereoselective hydroboration and hydrogenation of olefins as key steps are described here, respectively.

1,6-Anhydro-β- l -hexopyranoses as valuable building blocks toward the synthesis of l -gulosamine and l -altrose derivatives via the regioselective triflation and benzoylation of 1,6-anhydro-β- l -idopyranose followed by SN2 substitution with various nucleophiles as key steps is described here.

A highly regioelective and stereoselective benzoylation of the 2-N-protected 4,6-O-ketal derivatives of d -glucosamines with 1-(benzoyloxy)benzotriazole that affords the corresponding β anomeric benzoates in excellent yields is described herein.

A practical route toward the synthesis of 6-deoxy- l -idose and l -acovenose from 1,2:5,6-di- O -isopropylidene-α- d -glucofuranose is described. Key steps include the stereoselective hydrogenation of 6-deoxy-1,2:3,5-di- O -isopropylidene-α- d - xylo -hex-5-enofuranose, regioselective protection of 6-deoxy-1,2- O -isopropylidene-β- l -idofuranose at O-5, and epimerisation of 6-deoxy-5- O - tert -butyldimethylsilyl-1,2- O -isopropylidene-β- l -idofuranose at C-3.

Acetolysis of 1,6-anhydro-β-hexopyranoses and solvent-free per-acetylation of hexoses with acetic anhydride at room temperature in excellent yields employing 0.5 mol% scandium(III) trifluoromethanesulfonate as an extremely efficient catalyst are, respectively, described here.

A highly regioselective borane-reductive ring opening of the 4,6-O-benzylidene-d-hexopyranosides to the corresponding 6-alcohols in excellent yields at room temperature via various metal trifluoromethanesulfonates as catalysts is described here. Its application in the synthesis of 1,4-dideoxy-1,4-imino-l-xylitol is also highlighted.

Making ends meet: The L-gulopyranosyl trichloroacetimidate and 1,6-anhydro-2,3-di-O-benzyl-beta-L-gulopyranose, efficiently derived from L-ascorbic acid, were individually used as a starting unit and an elongation unit to prepare L-guluronic acid linked alginate oligosaccharides in excellent alpha selectivity and in good yields.