• Weed & Turfgrass Science
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• v.6 no.2
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• pp.151-156
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• 2017

Summer patch is the most serious disease at turfgrass field or golf course established with Kentucky bluegrass during high temperature season in Korea. Nevertheless, chemicals for the summer patch control are not yet registered in Korea. We isolated the pathogens from the turfgrass showing typical summer patch symptoms and identified as Magnaporthiopsis poae by using the internal transcribed spacer ITS1 and ITS4 sequences of rDNA. The inhibition rates of the pathogen were investigated for 10 fungicides. As results, the pathogen growth was suppressed when chemicals concentration increased and negatively correlated with incubation period with the chemicals. In triazole group, all chemicals (metconazole, myclobutanil, propiconazole and tebuconazole) treated showed the inhibition rates by 100%. Thiophanate-methyl showed the next highest inhibition effect against a summer patch pathogen. In strobilurin group, pyraclostrobin was the highest suppression effect compared with azoxystrobin and trifloxystrobin. Inhibition effect of fludioxonil and fluxapyroxad on pathogen was similar to the trifloxystrobin. Based on the results, triazole and carboxamide groups are strongly recommended due to the highest inhibition effect on the summer patch pathogen, Magnaporthiopsis poae.

• Analytical Science and Technology
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• v.16 no.6
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• pp.483-487
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• 2003

Amitrole is well-known as a non-selective herbicide and it is able to cause contamination of driking water as well as pollution of ground water and surface water. However, it is difficult to extract from water because it has a high solubility for water whereas a low solubility for general organic solvents. This method is described for the determination of amitrole in water samples by GC/MS. After evaporation of 10 mL water sample by a vacuum evaporator, amitrole was derivatized with isobutyl chloroformate (iso-BCF) on room temperature for 15~20 min. As a result, the sensitivity for GCfMS was improved as N-isobutoxycarbonyl amitrole derivative was formed. The linearity of the calibration curve showed good as 0.997. The recoveries were obtained more than 94.9% and relative standard deviations were less than 2.8% at $1.0{\mu}g/L$, $10.0{\mu}g/L$ and $100.0{\mu}g/L$. The limit of detection showed $0.1{\mu}g/L$ with a signal-to-noise ratio (S/N) of 3.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.130-137
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• 2020

BACKGROUND: Mefentrifluconazole and triticonazole are the triazole fungicides. The maximum residue levels for agricultural products need to be set up. Therefore, development of the official analytical method for determination of mefentrifluconazole and triticonazole residues from agricultural crops was necessary due to safety management, and then a simultaneous analytical method was developed for the determination of mefentrifluconazole and triticonazole in agricultural crops. METHODS AND RESULTS: Samples were extracted using acetonitrile and purified using dispersive solid phase extraction, and then detected with liquid chromatograph-tandem mass spectrometry (LC-MS/MS). Matrix-matched calibration curves (0.0025-0.25 ㎍/mL) were linear into a sample extract with r²>0.99. For validation, the recovery test was carried out at three fortification levels (LOQ, 10 LOQ and 50 LOQ) from agricultural samples. The results for mefentrifluconazole and triticonazole ranged between 92.3 to 115.3% and 91.4 to 108.5%, respectively and RSD (relative standard deviation) values were also below 6.0%. Furthermore, inter-laboratory was conducted to validate the method. CONCLUSION: All values were corresponded with the criteria ranges requested by both the CODEX (CAC/GL 40-1993, 2003) and MFDS guidelines (2016). Therefore, the proposed method can be used as an official analytical method for determination of mefentrifluconazole and triticonazole (triazole fungicides) in the Republic of Korea.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.69-75
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• 2012

In response of fungicides for control of gray snow mold, isolates of Typhula incarnata were collected from three golf courses in 2012 Yongpyeong, Korea and tested for sensitivity to propiconazole, tebuconazole and azoxystrobin fungicides. Four discriminatory concentrations were used to detect in vitro sensitivity of 50 isolates. Mean 50% effective concentration inhibiting mycelial growth ($EC_{50}$) values for tebuconazole was the lowest among the three fungicides. The $EC_{50}$ value of tebuconazole ranged from 0.0005 ${\mu}g\;ml^{-1}$ to 0.014 ${\mu}g\;ml^{-1}$ with a mean of 0.0048 ${\mu}g\;ml^{-1}$. The mean $EC_{50}$ values of propiconazole in triazole family was 0.5825 (0.78-1.651) ${\mu}g\;ml^{-1}$. $EC_{50}$ value of azoxystrobin ranged from 0.0017 ${\mu}g\;ml^{-1}$ to 0.131 ${\mu}g\;ml^{-1}$ with a mean of 0.0278 ${\mu}g\;ml^{-1}$. There was no correlation among $EC_{50}$ values for propiconazole, azoxystrobin and tebuconazole indicating no cross-resistance relationships with each other. Results of this study were confirmed no resistance isolates in vitro sensitivity of T. incarnata of three fungicides in Yongpyeong.

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.2985-2990
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• 2012

New thiazoline derivatives 7a-c, and thiophenes 9a-c linked to indole moiety were easily prepared via the reaction of the acrylamide derivative 3 with phenacyl bromides 4a-c, depending on the reaction conditions. In addition, the reaction of compound 3 with hydrazonoyl chlorides 11a-f afforded a series of 1,3,4-thiadiazole derivatives 13a-f. Moreover, coupling of 3-(3-methyl-1H-indol-2-yl)-3-oxopropanenitrile (2) with the diazonium salts of 3-phenyl-5-aminopyrazole 16 or 3-amino-1,2,4-triazole 17 gave the corresponding hydrazones 18 and 19, respectively. Cyclization of the latter hydrazones yielded the corresponding pyrazolo[5,1-c]-1,2,4-triazine and 1,2,4-triazolo[5,1-c]-1,2,4-triazine derivatives 20 and 21, respectively. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, $^1H$ NMR and mass spectral data. All the synthesized compounds were tested for in vitro activities against certain strains of fungi such as Aspergillus niger, Aspergillus nodulans, Alternaria alternate. Compounds showed marked inhibition of fungal growth nearly equal to the standards.

• Journal of the Korean Chemical Society
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• v.64 no.1
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• pp.7-18
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• 2020

An efficient and facile procedure has been developed for the synthesis of novel bichalcone derivatives (4a, 4b). The key step contains the solvent-free aldol synthesis of bichalcones based on quinones. Bichalcones (4a, 4b) were used as precursors for the synthesis of some interesting heterocyclic compounds like, diazepines (5a, 5b), pyrazolo-pyrimidines (7a, 7b), and pyrazoline derivatives (8a, 8b). Moreover, new thioxopyrimidine derivatives (9a, 9b) were furnished and used as a functionalizing agent to produce the triazole-pyrimidines (11, 12) and the carbonitrile derivative (14). All the synthesized compounds were fully characterized using physical and spectral data like, FT-IR, ¹H NMR, ¹³C NMR, and MS. Bichalcones (4a, 4b) and diazepines (5a, 5b) were screened for their anticonvulsant activity, where compounds (4a, 5a, and 5b) revealed potent anticonvulsant activity compared to diazepam. On the other hand, some of the prepared compounds were screened for their antiproliferative activity and they showed significant cytotoxic effects on most of the cancer cell lines with regard to broad spectrum antitumor activity.

• KSBB Journal
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• v.26 no.3
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• pp.217-222
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• 2011

Itraconazole is a triazole antifungal agent to inhibit most fungal pathogens. To improve the oral absorption and dissolution of poorly water-soluble itraconazole, microsponge system composed of $Eudragit^{(R)}$ E100 and polyvinyl alcohol(PVA) formulated by quasi-emulsion solvent diffusion method, and its physicochemical properties and pharmacokinetic parameters of itraconazole were studied. The microsponge of itraconazole were discrete free flowing micro sized particles with perforated orange peel like morphology as visualized by scanning electron microscope (SEM). Results showed that the drug loading efficiency, production yield, and particle size of itraconazole microsponge were affected by drug to polymer ratio, the volume of internal phase containing methylene chloride, stirring rate and the concentration of PVA used. Also, the results showed that the dissolution rate of itraconazole from the microsponges was affected by drug to polymer ratio. In other words, the release rate of itraconazole from microsponges was increased from at least 27.43% to 64.72% after 2 h. The kinetics of dissolution mechanism showed that the dissolution data followed Korsmeyer-Peppas model. Therefore, these results suggest that microsponge system can be useful for the oral delivery of itraconazole by manipulating the release profile.

• Transactions on Electrical and Electronic Materials
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• v.12 no.2
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• pp.80-83
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• 2011

We have fabricated phosphorescent white organic light-emitting devices (WOLEDs) with a spin-coated poly(Nvinylcarbazole) [PVK] host layer. Iridium(III) bis[(4,6-difluorophenyl)-pyridinato-N,$C^{2'}$]picolinate (FIrpic), tris(2-phenylpyridine)iridium(III) [$Ir(ppy)_3$], and tris(2-phenyl-1-quinoline)iridium(III) [$Ir(phq)_3$], were used as the blue, green, and red guest materials, respectively. The PVK was mixed with FIrpic, $Ir(ppy)_3$, and $Ir(phq)_3$ molecules in a chlorobenzene solution and spin-coated in order to prepare the emission layer; 3-(4-biphenylyl)-4-phenyl-5-(4-tertbutylphenyl)-1,2,4-triazole (TAZ) was used as an electron transport material. The resultant device structure was ITO/PVK:FIrpic:$Ir(ppy)_3:Ir(phq)_3$/TAZ/LiF/Al. The electroluminescence, efficiency, and electrical conduction characteristics of the WOLEDs based on the doped PVK host layer were investigated. The maximum current efficiency of the three wavelength WOLED with the doped PVK host was 19.2 cd/A.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.165-171
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• 2005

Itraconazole is a triazole antifungal agent to inhibit most fungal pathogens. However, it is difficult for itraconazloe to be delivered by topical system due to its poor aqueous solubility. First, niosomes containing drug were prepared with span 60, cholesterol. tocopherol and poloxamer 407 as vesicle forming agents in an effort to increase solubility of itraconazole. And then prepared niosomes were dispersed in O/W creams (containing xanthan gum, glycerin, vaseline, glyceryl monostearate and $Cerix^{\circledR}-5$) or gels (containing xanthan gum and poloxamer 407). Both creams and gels were evaluated with respect to their rheological properties, in vitro permeation through excised skin of hairless mouse. Creams or gels containing niosome showed pseudoplastic flow and hysteresis loop. For both creams and gels, viscosity was increased with increasing the content of glycerine or vaseline and the content of gel forming polymer, respectively. In creams, the permeability of drug to skin was decreased with increasing the viscosity of cream. The permeability of drug was affected by pH as well as viscosity of gel. In vitro permeation test results demonstrated that cream formulations showed better permeability than gels. In conclusion, these results suggest that creams formulation containing niosome can be useful for the topical delivery of intraconazole.

• BMB Reports
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• v.31 no.2
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• pp.144-148
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• 1998

A bifunctional catalase-peroxidase, designated catalase-2, of a UV resistant Deinococcus radiophilus was purified to electrophoretic homogeneity by both chromatographic and electrophoretic methods. Its molecular weight was 310 kDa and composed of a tetramer of 80 kDa subunits. The catalase-2 exerted its optimal activity at $30^{\circ}C$ and around pH 9. Its $K_m$ value for $H_{2}0_{2} $ was about 10 mM. It showed the typical ferric heme spectrum with maximum absorption at 403 nm which shifted to 419 nm in the presence of cyanide. The ratio of A40i' A2S0 was 0.48. Fifty percent inhibition of the enzyme activity was observed at $4.6{\times}10^{-6}$, $7.7{\times}10^{-6}$, and $3.0{\times}10^{-6}$ M of NaCN, $NaN_3$, and $NH_{2}OH$, respectively. The enzyme was thermostable and not sensitive to 3-amino-1,2,4-triazole. Treatment of the enzyme with ethanol-chloroform caused a partial loss (30%) of its activity. The catalase-2 was distinct from the Deinococcal bifunctional catalase-3 in a number of properties, particularly in its molecular structure and substrate affinity.