• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.29-31
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• 2000

New convenient and economical synthesis of 5,6-dihydro-2-methyl-1,4-oxathiin-3-carboxanilide 1 and the plausible reaction mechanism were described. Reaction of ${\alpha}$-chloroacetoacetanilide 4 (1 molar equivalent) with 2-mercaptoethanol (1.2 molar equivalent) in the presence of p-toluenesulfonic acid monohydrate (0.05 molar equivalent) as a catalyst in refluxing toluene with water trap yielded carboxin 1. The proposed mechanism is that ${\alpha}$-chloro 1,3-oxathiolane 8 which is a heuithioketal of 4 was converted to unisolable sulfonium ion 9 through neighboring group participation of sulfur followed by rearrangement to more stable oxonium ion 12 and then release acidic proton to produce the carboxin 1.

• Journal of the Korean Chemical Society
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• v.25 no.1
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• pp.44-49
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• 1981

Bromination of acetoacteanilide in non-polar medium gives the r-brominated derivative. This unexpected result may be due to the steric hinderance during the enolization of the substrate. The structure of r-bromoacetoacetanilide can be assigned on the basis of its 1H NMR spectrum. Additional evidence is provided by making derivatives, whick proceed without skeletal rearrangements. Structural similarity of 2-(N-phenylcarbamoyl)methylene-1,4-oxathiane with carboxin which is used as a potent fungicide prompted our investigation of the 1,4-oxathiane synthesis. It is prepared from the reaction of r-bromoacetoacetanilide with mercaptoethanol followed by acidic dehydration in high yield.

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.185-190
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• 2005

Solid phase synthesis of 16, which is a derivative of the first systemic fungicide, carboxin 1 was described. Reaction of 1,3-oxathiolane derivative with solid resin of 4-hydroxy-3-nitrobenzophenone 6 gave 9 in 82% yield. Oxidation of sulfur in the solid 1,3-oxathiolane 9 by MCPBA followed by a ring expansion reaction under the acid catalyst afforded the corresponding dihydro-1,4-oxathiin derivative 12. Treatment of the solid 1,3-oxathiolane 9 with p-methoxyaniline resulted in 1,3-oxathiolane 14, 1,3-oxathiolane sulfoxide 15, dihydro-1,4-oxathiin 16, and acetoacetanilide derivative 17 in 41%, 35%, 14%, 10% yields, respectively.

• Plant Resources
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• v.8 no.2
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• pp.130-134
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• 2005

This study was conducted to evaluate the control effect of fungicides on control of Gray mold, growth characteristics, and root yield in the cultivation of Scutellaria baicalensis after barley cropping. All fungicides treated had no effect on the growth and flowering rate of Scutellaria baicalensis. All seed disinfectants had no effect on the growth and flowering date of Scutellaria baicalensis Georg. The major seed disinfectants were Benomyl Wp, $20\%$, Captan Wp, $50\%$, Hymexazol Ec, $30\%$, Carboxin D, $37.5\%$. Dry root yield were increased largely with Benomyl Wp, $20\%$, seed disinfectant than the other seed disinfectants had no injury with standard dosage. On the other hand, all seed disinfectants had slight injury in the double dosage level for the Scutellaria baicalensis Georg.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.271-276
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• 2009

Functional gene studies in the cultivated white button mushroom Agaricus bisporus have been constrained by the absence of effective gene-silencing tools. Using two endogenous genes from A. bisporus, we have tested the utility of dsRNA hairpin constructs to mediate downregulation of specific genes. Hairpin constructs for genes encoding orotidine 5'-monophosphate decarboxylase (URA3) and carboxin resistance (CBX) were introduced into A. bisporus using Agrobacteriummediated transfection. Although predicted changes in phenotype were not observed in vitro, quantitative-PCR analyses indicated unambiguously that transcripts in several transformants were substantially reduced compared with the non-transformed controls. Interestingly, some hairpin transformants exhibited increased transcription of target genes. Our observations show that hairpin transgenic sequences can mediate downregulation of A. bisporus endogenous genes and that the technology has the potential to expedite functional genomics of the mushroom.

• Korean Journal of Medicinal Crop Science
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• v.23 no.6
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• pp.460-467
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• 2015

Background : The aim of the present study was to identify an effective physicochemical control method to reduce Fusarium species infestation in adlay (Coix lacryma-jobi L.) before and after harvesting. Methods and Results : We observed that prochloraz emusifiable concentrate and hexaconazol prochloraz emusifiable concentrate strongly inhibited the mycelial growth of 10 Fusarium species. Strong growth inhibitions and cell lysis were observed following treatment with 4% NaOCl solution. The total number of fungi detected were lower follwing treatment with thiophanatemethyl triflumizole wettable powder ($1.1{\times}10^4CFU/g$), hexaconazol prochloraz emulsifiable concentrate ($1.2{\times}10^4CFU/g$), carboxin thiram dustable powder ($1.6{\times}10^4CFU/g$) and prochloraz emulsifiable concentrate ($1.7{\times}10^4CFU/g$) than in the non-treated control ($7.7{\times}10^4CFU/g$). The reduction of Fusarium fungi varies with the concentration and soaking time of NaOCl solution. Fungal detection was not observed after soaking in NaOCl solution for 24 h and harmful effects were not observed for plant growth by NaOCl after soacking for 6 - 12 h. Conclusion : Soaking seed for 6 - 12 h in 4% NaOCl could be an effective method of disinfectant treatment for the control of Fusarium fungi in adlay seeds.