Publication Date:
2012-09-15
Description:
Five novel pyrazole-coupled glucosides, 1,5-diaryl-1 H -pyrazol-3-yl 2,3,4,6-tetra- O -acetyl- β - D -glucopyranosides 5a – 5e , were synthesized by the phase-transfer catalytic reaction of 1,5-diaryl-1 H -pyrazol-3-ols 4a – 4e with acetobromo- α - D -glucose in H 2 O/CHCl 3 under alkaline conditions, using Bu 4 N + Br − as catalyst. Then, glucosides 5a – 5c were deacetylated in a solution of Na 2 CO 3 /MeOH to yield the 1,5-diaryl-3-( β - D -glucopyranosyloxy)-1 H -pyrazoles 6a – 6c . Their structures were characterized by 1 H, 1 H-COSY, 1 H-, 13 C-, and 19 F-NMR spectroscopy, as well as elemental analysis. The structures of 5d and 6c were also determined by single-crystal X-ray diffraction analysis. A preliminary in vitro bioassay indicated that compounds 4e and 5d exhibited excellent-to-medium fungicidal activity against Sclerotinia sclerotiorum at the dosage of 10 μg/ml.
Print ISSN:
0018-019X
Electronic ISSN:
1522-2675
Topics:
Chemistry and Pharmacology
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