thiourea and ethyl-acetoacetate

Sixteen novel pyrazole acyl thiourea derivatives 6 were synthesized from monomethylhydrazine (phenylhydrazine) and ethyl acetoacetate. The key 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl chloride intermediates 4 were first generated in four steps through cyclization, formylation, oxidation and acylation. Thess were then reacted with ammonium thiocyanate in the presence of PEG-400 to afford 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl isothiocyanates 5. Subsequent reaction with fluorinated aromatic amines resulted in the formation of the title compounds. The synthesized compound were unequivocally characterized by IR, ¹H-NMR, ¹³C-NMR and elemental analysis and some of the synthesized compounds displayed good antifungal activities against Gibberella zeae, Fusarium oxysporum, Cytospora mandshurica and anti-TMV activity in preliminary antifungal activity tests.

Topics: Acetoacetates; Acylation; Antifungal Agents; Antiviral Agents; Cyclization; Fusarium; Gibberella; Hydrocarbons, Fluorinated; Microbial Sensitivity Tests; Oxidation-Reduction; Phenylhydrazines; Polyethylene Glycols; Pyrazoles; Structure-Activity Relationship; Thiocyanates; Thiourea; Tobacco Mosaic Virus