Preliminary Study on Novel Expedient Synthesis of 5-Azaisocoumarins by Transition Metal-Catalyzed Cycloisomerization.

A preliminary study to develop a novel synthetic method for 3-aryl-5-azaisocoumarins was performed herein. The cycloisomerization of -pyranonyl propargylamines in the AgOTf-catalyzed system efficiently afforded the desired 3-aryl-5-azaisocoumarins in a highly regioselective manner. This unprecedented method is expected as an expedient alternative synthetic route to 5-azaisocoumarins because the regioselectivity problem is circumvented, and it is easier to introduce substituents on the pyridine ring compared to previously reported intramolecular lactonization approaches.

The first synthesis and immunomodulatory properties of -hydroxyphenyl caffeate derived from .

Herein, we report a concise and efficient method for the synthesis of -hydroxyphenyl caffeate, a novel natural caffeic acid ester derivative isolated from . The key feature of this synthesis is the Verley-Doebner modification of the Knoevenagel condensation of the -hydroxyphenyl malonate intermediate. The synthesized -hydroxyphenyl caffeate enhanced interleukin 2 production by murine lymph node T cells, and suppressed interleukin 13 production by murine epidermal T cells.

Isolation of acid tolerant lactic acid bacteria and evaluation of α-glucosidase inhibitory activity.

In this study, lactic acid bacteria strains (LABs) were isolated from Korean traditional fermented food and examined as potential probiotics using in vitro methods. Ten LAB strains survived in de Man, Rogosa and Sharpe broth adjusted to pH 2.5 were tested for resistance to acidic conditions and bile, antimicrobial activity, and α-glucosidase inhibitory activity.

Design and in vivo evaluation of entecavir-3-palmitate microcrystals for subcutaneous sustained delivery.

The objectives of this study were to formulate microcrystals of entecavir-3-palmiate (EV-P), a palmitic acid ester of entecavir (EV), and evaluate the influence of particle size on its pharmacokinetic behavior following subcutaneous (SC) injection. Systemic toxicity and local tolerability of the hepatitis B anti-viral suspension were further evaluated in normal rats. EV-P microcrystals possessing median diameters of 2.

Microsuspension of fatty acid esters of entecavir for parenteral sustained delivery.

Entecavir (EV), an anti-viral agent for hepatitis B infection, should be administered under fasted state, as intestinal absorption of this hydrophilic compound is markedly decreased under post-prandial conditions. Herein, in order to improve therapeutic adherence, a parenteral sustained delivery system was constructed, by synthesizing water-insoluble ester prodrugs of the nucleotide analogous with fatty acids. EV-3-palmitate (named EV-P), exhibited the lowest solubility in phosphate buffered saline (pH 7.

Stroke Impact Scale 3.0: Reliability and Validity Evaluation of the Korean Version.

Objective: To establish the reliability and validity the Korean version of the Stroke Impact Scale (K-SIS) 3.0.

Methods: A total of 70 post-stroke patients were enrolled.

Evolution of high-temperature molecular relaxations in poly(2-(2-methoxyethoxy)ethyl methacrylate) upon network formation.

Copolymers of 2-(2-methoxyethoxy)ethyl methacrylate (poly(MEOMA)) are regarded as bioinert replacements of poly(-isopropylacrylamide) in some biomedical applications. Networks of poly(MEOMA) of various architecture form thermo-responsive hydrogels. Here, we present dielectric and mechanical spectroscopy studies on segmental motions and network relaxation processes in linear poly(MEOMA) and its networks - bare network and the network grafted with short poly(MEOMA) chains.

Synthesis of flavonoid O-pentosides by Escherichia coli through engineering of nucleotide sugar pathways and glycosyltransferase.

Plants produce two flavonoid O-pentoses, flavonoid O-xyloside and flavonoid O-arabinoside. However, analyzing their biological properties is difficult because flavonoids are not naturally produced in sufficient quantities. In this study, Escherichia coli was used to synthesize the plant-specific flavonoid O-pentosides quercetin 3-O-xyloside and quercetin 3-O-arabinoside.

[Effectiveness of enneagram group counseling for self-identification and depression in nursing college students].

Purpose: The purpose of this study was to examine effects of enneagram group counseling program on self-identification and depression in nursing college students. Three groups, categorized by how the students solve their conflicts, were selected to identify changes from the program.

Methods: A quasi-experimental study with a non-equivalent control group and pre posttest design was used.

Production of a novel quercetin glycoside through metabolic engineering of Escherichia coli.

Most flavonoids exist as sugar conjugates. Naturally occurring flavonoid sugar conjugates include glucose, galactose, glucuronide, rhamnose, xylose, and arabinose. These flavonoid glycosides have diverse physiological activities, depending on the type of sugar attached.

Thermoresponsive hydrogel scaffolds with tailored hydrophilic pores.

Thermoresponsive hydrogels with efficient water-release channels were prepared by incorporating star-shaped macromolecular pore precursors, with degradable disulfide crosslinked cores and hydrophilic poly(ethylene oxide) (PEO) arms, into the gel network. The gel framework exhibiting lower critical solution temperature (LCST) behavior was synthesized by atom transfer radical polymerization (ATRP) of 2-(2-methoxyethoxy)ethyl methacrylate and ethylene glycol dimethacrylate. The incorporation of degradable star macromolecules (dSM) was facilitated by growing the gel from ATRP initiator sites contained within their cores.

Photo-cross-linkable thermoresponsive star polymers designed for control of cell-surface interactions.

Star polymers with thermoresponsive arms, consisting of 2-(2-methoxyethoxy)ethyl methacrylate (MEO₂MA) and oligo(ethylene glycol) methacrylate with ~4 ethylene oxide units (OEOMA₃₀₀, M(n) = 300), were synthesized via atom transfer radical polymerization (ATRP). 25% of the arms contained benzophenone chain-end functionality at the star periphery. A mixture of linear poly(MEO₂MA-co-OEOMA₃₀₀)-Br macroinitiators without and with benzophenone end-group macroinitiators were (MI and Bzp-MI, respectively) cross-linked with ethylene glycol dimethacrylate to form star polymers.

Thermocurable hyperbranched polystyrenes for ultrathin polymer dielectrics.

Thermocurable hyperbranched polystyrenes were successfully synthesized using atom transfer radical polymerization and exhibited superior ultrathin film formation capabilities in comparison with the linear analogues, as assessed by the minimal film thickness attainable by spin-coating without dewetting. They were suitable as ultrathin film organic dielectrics, with parallel plate specific capacitances as high as ∼680 nF/cm2. Similar to high performance inorganic dielectrics, capacitance measurements pointed to the presence of "dead" interfacial capacitance, which could be accounted for by considering the geometric effect of roughness "incommensurability" between metal electrode and polymer film.

Dual-reactive surfactant used for synthesis of functional nanocapsules in miniemulsion.

Dual-functional amphiphilic block copolymers, alpha-azido-omega-2-chloroisobutyrate-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-b-poly(n-butyl methacrylate), prepared by atom-transfer radical polymerization were used as dual-reactive surfactants (i.e., macroinitiators for a miniemulsion copolymerization of a monovinyl monomer and divinyl cross-linker as well as surfactants with latent functionality).

Facile synthesis of highly ordered mesoporous silver using cubic mesoporous silica template with controlled surface hydrophobicity.

Highly ordered mesoporous silver, which exhibits well-defined mesopores, high surface area and pore volume, has been successfully obtained using a cubic mesoporous silica, KIT-6, with controlled surface hydrophobicity as the hard template.

One-pot synthesis of robust core/shell gold nanoparticles.

A one-pot synthesis of thermally stable core/shell gold nanoparticles (Au-NPs) was developed via surface-initiated atom transfer radical polymerization (ATRP) of n-butyl acrylate (BA) and a dimethacrylate-based cross-linker. The higher reactivity of the cross-linker enabled the formation of a thin cross-linked polymer shell around the surface of the Au-NP before the growth of linear polymer chains from the shell. The cross-linked polymer shell served as a robust protective layer, prevented the dissociation of linear polymer brushes from the surfaces of Au-NPs, and provided the Au-NPs excellent thermal stability at elevated temperature (e.