• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.2
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• pp.75-79
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• 2015

[$^{18}F$]Fluorobenzaldehyde, which is a versatile radioactive prosthetic group, can undergo reduction, reductive amination, or oxidation to be used for synthesis of diverse radiotracers. This review covers synthesis of [$^{18}F$]fluorobenzaldehyde and its conversion to secondary prosthetic groups, and also highlights its application to the development of radiotracers.

• Phonetics and Speech Sciences
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• v.10 no.1
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• pp.49-55
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• 2018

This paper aims to describe a knowledge-based pronunciation generation system for French. It has been reported that a rule-based pronunciation generation system outperforms most of the data-driven ones for French; however, only a few related studies are available due to existing language barriers. We provide basic information about the French language from the point of view of the relationship between orthography and pronunciation, and then describe our knowledge-based pronunciation generation system, which consists of morphological analysis, Part-of-Speech (POS) tagging, grapheme-to-phoneme generation, and phone-to-phone generation. The evaluation results show that the word error rate of POS tagging, based on a sample of 1,000 sentences, is 10.70% and that of phoneme generation, using 130,883 entries, is 2.70%. This study is expected to contribute to the development and evaluation of speech synthesis or speech recognition systems for French.

• Biomedical Science Letters
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• v.15 no.2
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• pp.105-112
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• 2009

The screening of the anti-cancer activity of the chemical library provided 2-thio-4-aminopyrimidine as the initial hit. The confirmation of structure and biological effect of hit was performed by synthesis and biological evaluation. The optimization of hit was performed by derivatization of substituents while keeping the core structure. The evaluation of growth inhibitory activity was carried out using SRB assay against 6 human cancer cell lines and human fibroblast. The growth inhibitory activity of compounds showed substituent dependency and more than 5 compounds showed complete growth inhibition of cancer cell lines at 10 ${\mu}M$ concentration. Chemical library screening followed by synthetic modification provided possibility that 2-thio-4-aminopyrimidine can be used as a new scaffold for the development of anti-cancer agent.

• Journal of Integrative Natural Science
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• v.8 no.3
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• pp.153-163
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• 2015

Racemic synthesis of novel 5',5'-difluoro-2'-methyl-apiose nucleoside phosphonic acid analogs was achieved as potent antiviral agents. Phosphonation was performed by direct displacement of triflate intermediate with diethyl (lithiodifluoromethyl) phosphonate to give the corresponding (${\alpha},{\alpha}$-difluoroalkyl) phosphonate. Condensation successfully proceeded from a glycosyl donor with persilylated bases to yield the nucleoside phosphonate analogs. Deprotection of diethyl phosphonates provided the target nucleoside analogs. An antiviral evaluation of the synthesized compounds against various viruses such as HIV, HSV-1, HSV-2 and HCMV revealed that the pyrimidine analogs (cytosine, uracil, and thymine) have weak anti-HIV or HCMV activity.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.266-266
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• 2006

The cell spheroid (multicellular mass) is enhanced cell functions because of the cell-cell interaction compared with the individual cell. The objective of this study is synthesis, characterization and evaluation of novel crosslinkers to form spheroid in a short time. Our approach to bridge cells is based on the crosslinking of the cell membrane via the hydrophobic interaction. The crosslinker was prepared by the reaction between ethylenediamine and poly(ethylene glycol) (PEG) derivative with oleyl group as hydrophobic group at the terminal group. The product was characterized with gel permeation chromatography (GPC) and FT-IR. Furthermore, cell culture experiment was also performed to confirm spheroid formation. The function of prepared spheroids was evaluated.

• Archives of Pharmacal Research
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• v.21 no.1
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• pp.73-75
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• 1998

In summary, six 4-substituted-1-azzanthraquinones were designed and synthesized using hetero Diels-Alder reaction as a key step. Although a great number of reaction conditions for benzylic bromination were examined, this step need to be improved for the efficient synthesis of the related analogues. 4-Bromomethyl-1-azzanthraquinone 6 may have potential for the treatment of tumors resistant to the doxorubicin. The compounds 9 and 10 containing the latent alkylating functionality may need further in depth biological evaluation. Work is in progress to design, synthesize, and evaluate additional compounds in this and related systems.

• Fibers and Polymers
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• v.3 no.4
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• pp.140-146
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• 2002

Non-genotoxic diamines 2,2'-dimethyl-5,5'-dipropoxybenzidine and 5,5'-dipropoxy-benzidine were employed as potential alternatives to benzidine in the synthesis and evaluation of new direct dyes for cotton. Assessment of the resultant dyes indicated that both diamines can be used to prepare new direct dyes having colors and fastness properties that make them comparable to commercial direct dyes, and that the structures of the new direct dyes can be confirmed by negative ion electrospray mass spectrometry (ESMS). The mutagenic properties of new direct dyes were established using the standard Ames Salmonella mammalian mutagenicity assay.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.570-580
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• 1996

Design and synthesis of novel 4-phenyl-1-arylsulfonylimidazolones 3 and 4-phenyl-3-arylsulfonylimidazolones 4 and evaluation of their cytotoxic activity against eleven human cancer cell lines and two murine leukemia cell lines in vitro were performed. As a result, a series of 4-phenyl-1(N)-arylsulfonylimidazolones (3) has been found to be the potential anticancer agent. Compounds 3b, 3c, and 3d exhibit strong activity as indicated by their $IC_{50}$ values 0.39, 3.19, $0.31{\mu}g/mL$ against A549 and 0.80, 0.48, $0.0007{\mu}g/mL$against SK-Mel-2, respectively. These compounds also possess much more potent activity (10-1000 times) than LY186641 against eleven other cell lines.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.90-99
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• 2000

This report describes the results of analysis, synthesis and evaluation of antimony dithiocarbamates (SbDTC). Sb-DTC were synthesized by reacting antimony oxide with dithiocarbamates whish were prepared by reaction of dialkylamines and carbon disulfide. The chemical structures and properties of synthesized Sb-DTCs in lab. were discussed. The frictional properties of SbDTC were tested with Four-Ball Wear Scar Tester and Four-Ball Extreme Tester by ASTM method.

• Journal of the Korean Ceramic Society
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• v.56 no.6
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• pp.541-548
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• 2019

Zirconia (ZrO₂) materials are widely used in a variety of energy systems and devices. When nanorod-shaped ZrO₂ is used as energy materials, ionic conductivity and mechanical strength can be improved compared to the characteristics of conventional spherical-shaped nanomaterials. In this study, we synthesized ZrO₂ nanorods and investigated the shape change of them depending on various synthesis conditions such as precursor concentration, synthesis temperature, synthesis period, and aging period. The obtained nanorods were casted into a membrane for alkaline water electrolysis system and subjected to basic performance evaluation for use as a separator. The structure and the shape of the nanorods were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and the like.