5-Methyl-1,2,3-thiadiazoles synthesized via ugi reaction and their fungicidal and antiviral activities.
ABSTRACT 1,2,3-Thiadiazoles, an important synthetic active substructure, are nowadays becoming one of the important branches in novel pesticide development. To develop pesticide candidates with diverse biological activities and probe their structure-activity relationship, three series of 5-methyl-1,2,3-thiadiazoles were rationally designed and synthesized using a simple and convenient one-step synthetic procedure via Ugi reaction. Biological activities of the target compounds including fungicidal activity, antivirus activity in vitro and in vivo, and systemic acquired resistance were systematically evaluated. The results indicated that compound III(10) showed broad-spectrum of activities against most fungi tested, and compounds I(10) and II(17) showed excellent potential antivirus activities as compared to positive control agent ribavirin. The preliminary structure-activity relationship was also discussed. The results of these studies indicated that the 5-position-substituted 1,2,3-thiadiazoles exhibited good antivirus activity and were worthy of further study in pesticide development.
- [Show abstract] [Hide abstract]
ABSTRACT: Abstract The title compounds, quinolin-8-yl 4-methyl-1,2,3-thiadiazole-5-carboxylate 2a and 2-nitrophenyl 4-methyl-1,2,3-thiadiazole-5-carboxylate 2b, synthesized by the reaction of 4-methyl-1,2,3-thiadiazole-5-carbonyl chloride with 8-hydroxyquinoline and 2-nitrophenol, were confirmed by single-crystal X-ray diffraction [CCDC 783328 and 784970]. The 2a crystallizes in triclinic space group P-1 with cell parameters a = 7.957(7) Å, b = 8.378(7) Å, c = 10.097(10) Å, α = 100.63(2)°, β = 112.742(17)°, γ = 93.287(4)° and Z = 2. The 2b crystallizes in triclinic space group P-1 with cell parameters a = 7.134(4) Å, b = 8.154(4) Å, c = 10.254(5) Å, α = 99.501(9)°, β = 91.311(7)°, γ = 109.518(8)° and Z = 2. Packing in the compound 2a is dominated by weak C–H···N and C–H···O hydrogen bonds. In the compound 2b, molecules are linked through intermolecular C–H···O hydrogen bonds interactions. The preliminary bioassay showed that the title compound 2a had excellent antifungal activity with the EC50 detected as from 2.99 to 28.35 μg/mL and the EC90 detected as from 21.041 to 175.17 μg/mL. Both of the title compounds 2a and 2b had good inhibition activity of tobacco mosaic virus (TMV) and good induction activity of tobacco against TMV with potential systemic acquired resistance. Graphical Abstract Two 1,2,3-thiadiazole derivatives C13H9N3O2S (2a) and C10H7N3O4S (2b), synthesized by the reaction of 4-methyl-1,2,3-thiadiazole-5-carbonyl chloride with 8-hydroxyquinoline and 2-nitrophenol, were confirmed by single-crystal X-ray diffraction. The preliminary bioassay shows that the title compound 2a has excellent antifungal activity. Both of the title compounds 2a and 2b had good inhibition activity of tobacco mosaic virus (TMV) and good induction activity of tobacco against TMV with potential systemic acquired resistance.Journal of Chemical Crystallography · 0.51 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The title compound, N′-tert-butyl-N-(3-methoxylbenzoyl)-N-(4-methyl-1,2,3-thiadiazole-5-formylhydrazine (C16H20N4O3S) was prepared from the reaction of 4-methyl-1,2,3-thiadiazole-5-carbonyl chloride with N′-tert-Butyl-3-methoxylbenzohydrazine, and its structure was characterized by 1Hydrogen Nuclear Magnetic Resonance, High-Resolution Mass Spectrometry, IR spectra, and single crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic system, space group P 21/c with cell parameters a = 17.986(2) Å, b = 8.0180(10) Å, c = 12.0190(14) Å, α = 90°, β = 91.160(5)°, γ = 90°, V = 1732.9(4) Å3, Z = 4, D c = 1.335 g/cm3, μ (Mo Ka) = 0.209 mm−1, F (000) = 736, R = 0.0367 and wR = 0.0932. X-ray diffraction analysis indicates that all rings in the title compound are non-planar. The bioassay results indicated that, the title compound had good fungicide activity against Sclerotinia sclerotiorum, certain extent of insecticidal activity against Plutella xylostella L. Graphical Abstract .Journal of Chemical Crystallography 12/2011; 41(12). · 0.51 Impact Factor