• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3297-3300
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• 2010

In this study, the 3D-QSARs (three-dimensional quantitative structure-activity relationships: CoMFA and CoMSIA) between structural changes of N-phenyl-O-phenylthionocarbamate analogues (1-30) and their fungicidal activities against the capsicum phytophthora (Phyophthora capsici) fungi were analyzed, then considered quantitatively in terms of minimum structural requirements for fungicidal evaluation. The statistical qualities ($r^2_{cv.}$ = 0.510 and $r^2_{ncv.}$ = 0.948) of the optimal CoMFA 1 model are improved over the other models in the conditions of field combinations, and the two alignments. In the optimal CoMFA 1 model, relative contribution percentages of the CoMFA field were: steric field, 52.3%; electrostatic field, 37.8%; hydrophobic field, 9.9%. Results were similar for the CoMFA 2 model. Therefore, the steric field of the analogues had the highest contribution ratio for fungicidal activity. Specifically, with the contour map of steric fields, the fungicidal activity increased when bulky steric Y-substituents were introduced to the meta-position on the N-phenyl ring and small steric Y-subsituents were introduced to its para-position.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.442-446
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• 2005

Fungicidal activities of Cassia obtusifolia extracts and their active principles were tested against Botrytis cinerea, Erysiphe graminis, Phytophthora infestans, Puccinia recondita, Pyricularia grisea, and Rhizoctonia solani, and compared with synthetic fungicides and two dihydroxyanthraquinones. At 1 g/l, the chloroform fraction of C. obtusifolia extracts showed fungicidal activity against B. cinerea, E. graminis, P. infestans, and Py. grisea, and the ethyl acetate fraction showed fungicidal activity against E. graminis and P. infestans. Danthrone was chromatographically isolated from the chloroform fraction and showed fungicidal activity against B. cinerea, E. graminis, P. infestans, and Py. grisea with 68, 100, 78, and $91\%$ control values at 0.5 g/l, respectively. Specifically, alizarin and quinizarin inhibited E. graminis, P. infestans, and Py. Grisea, but did not inhibit the growth of P. recondita and R. solani. These results indicate at least one of the fungicidal actions of danthrone.

• Korean Journal of Agricultural Science
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• v.35 no.1
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• pp.33-40
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• 2008

The structural characteristics that influence on the fungicidal activities of N-phenylbenzenesulfonamide (1~24) and N-phenyltheinylsulfonamide (25~30) derivatives against Dampping-off (Pythium ultimum) were discussed quantitatively using the models of molecular holographic quantitative structure-activity relationships (HQSAR). From the based on these findings, the statistical results of the optimized HQSAR F-3 model showed better predictablity ($r^2_{cv.}$ or $q^2=0.581$) and correlation coefficient ($r^2_{ncv.}=0.963$). And, from the analytical results of the atomic contribution maps on the fungicidal activities, the most active compound is $R_1=2-fluoro-4-chloro$ substituent (4) and the most inactive one is $R_1=4-methoxy$ substituent (20). It was found that the 2-fluoro-4-chlorophenyl group as a $R_1$-group was an important structure and a characteristic factor not only for herbicidal activity but also for fungicidal activity.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1199-1214
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• 2002

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.86-89
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• 1999

A series of methanesulfonamide (I a- I g) and phenylhydrazone (IIa-IIh) derivatives were synthesized and their fungicidal activity in vitro against gray mold (BC: Botrytis cinerea), phytophthora blight (PC: Phytophthora capsici) and sheath blight (RS: Rhizoctonia solani) were measured by agar dilution method. The (II) deriviatives showed higher activity than ( I ) derivitives. And the relative orders of the fungicidal activity are BC=PC>RS, Among these compounds, 3-chlorophenyl substituent, IIg showed the most highest activity ($pI_{50}=3.96$) against PC. From the parameter focusing technique, major factors on the activity were ovality, polar and logP constant and so on.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.239-245
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• 1996

Fungicidal activity has been examined for a series of substituted phenylhydrazono-3-methyl-1,2-isoxazol-5-one against plant pathogenic fungi. 3-methyl isoxazol-5-one was obtained from ethyl acetoacetate and hydroxyl amine. Final products were prepared by aromatic diazo coupling with 3-methyl isoxazol-5-one. Fungicidal activities against Rhizoctonia solani, Colletotrichum gloeosporioides, Cladosporium cucumerinum, Pythium ultimum were tested and Pythium ultimum were tested and Pythium ultimum was selected for quantitative measurement of activity. Methyl, halogen, nitro derivatives possessed high fungicidal activity at p-, o-, p- position, respectively. Methyl, halogen derivatives were much more active than alkoxy, nitro derivatives and the order of activity of halogen derivatives was F > Cl > I. This result implied that the activity was related to the molecular volume of substitutents.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.303-308
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• 2006

Ethaboxam is a fungicide controlling plant diseases caused by Oomycetes. Efforts were made to improve its fungicidal activity applying formulation technology. Fungicidal activity of ethaboxam against cucumber downy mildew caused by Pseudoperonospora cubensis was improved by incorporating polyoxyethylene cetyl ether (PCE) in a wettable powder formulation. It was found that the optimum combination ratio of PCE and ethaboxam was 3:1, and a tank-mix of $150{\mu}g/ml$ of ethaboxam and $450{\mu}g/ml$ of PCE would be as good as the standard 25 % WP formulation diluted to $250{\mu}g/ml$ ethaboxam without PCE in controlling cucumber downy mildew. Based on this results, a wettable powder (WP) co-formulation containing 15% of ethaboxam and 45% of PCE was developed in this study, and tested for its performance in the fields. This co-formulation showed significant improvement in persistence of fungicidal activity and curative efficacy of ethaboxam against cucumber downy mildew. The improved control efficacy was also confirmed for control of grape downy mildew caused by Plasmopara viticola and potato late blight caused by Phytophthora infestans in the field tests.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.228-232
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• 1999

The combination effect of anethole with amphotericin B, fluconazole, miconazole, or 5-fluorocytosine was investigated against Saccharomyces cerevisiae. When combined with $\frac{1}{2}$ minimum inhibitory concentration (MIC) or $\frac{1}{2}$ minimum fungicidal concentration (MFC) of anethole, the antifungal activities of fluconazole and 5-fluorocytosine were not changed, but the fungistatic and the fungicidal activities of miconazole were increased 64-fold, respectively. In the case of amphotericin B, the fungistatic activity was increased 2-fold, while the fungicidal activity was decreased 2-fold. The combination effect of anethole with miconazole or amphotericin B was also investigated at the various concentrations using the macrobroth dilution checkerboard method. The fractional inhibitory concentration (FIC) and the fractional fungicidal concentration (FFC) index between B exhibited the FIC index of 8.25 and the FFC of 32.06, respectively. Thus, it is analyzed that the combination of anethole with miconazole or amphotericin B on the antifungal action shows synergism and antagonism, respectively.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.59-66
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• 2007

Three dimensional quantitative structure-activity relationships (3D-QSARs) on the fungicidal activity of N-phenyl-O-phenylthionocarbamate analogues against resistant and sensitive gray mold (Botrytis cinerea) (RBC & SBC) were studied quantitatively using CoMFA and CoMSIA methods. The correlation coefficient and predict- ability of optimized CoMFA model with the atom based fit alignment were better ($r^2$ & $q^2=CoMFA{\gg}CoMSIA$) than that of CoMSIA model. And statistical values of the models on the fungicidal activity against SBC were showed higher ($r^2=SBC{\gg}RBC$) than that of RBC. In CoMFA models, steric field on the activity was more influenced than electrostatic field. And in case of CoMSIA models, the influence of CoMSIA field on the activity against RBC and SBC was differ from each other but the influence of H-bond donor field was same to the two fungi. It is revealed that the selectivity factor with CoMFA model on the fungicidal activity between the two fungi was caused on the difference of steric field. Therefore, it is predicted that the large steric field with meta- and para-substituents on the N-phenyl ring will be improved to the fungicidal activity with SBC.

• Applied Biological Chemistry
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• v.41 no.8
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• pp.600-604
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• 1998

Methanol extracts from 53 species of oriental medicinal plants in 34 families were tested for their fungicidal activities against Pyricularia grisea, Rhizoctonia solani, Phytophthora capsici, Phytophthora infestans, Collectotrichum dematium, Botryospaeria dothidea, Fusarium oxysporum f. sp. cucumerinum, Botrytis cinerea, Puccinia recondita, and Erysiphe graminis. In in vitro study using impregnated paper disc method, the efficacy varied with both plant pathogen and plant species tested. Methanol extracts of Asarum sieboldii roots, Sinomenium acutum roots, Pinus densiflora leaves, Rheum undulatum root barks, Coptis japonica roots, and Phellodendron amurense barks showed potent fungicidal activities against the various pathogens when treated with 10 mg/disc. In a whole plant test, methanol extracts of P. densiflora leaves and roots and C. japonica roots were highly effective against a variety of plant pathogens. As a naturally occurring fungicide, P. densiflora- and C. japonica-derived materials could be useful as new fungicidal products against various plant diseases induced by plant pathogenic fungi.