| abstract |
Compounds of formula (I):n in which:n A represents a group of formula -CH=CH- or -CH 2 -CH 2 -; R 1 represents a halogen atom; R 2 represents a hydrogen atom, a hydroxy group, a halogen atom, an alkyl group or an alkoxy groupe; R 3 represents a hydrogen atom or a halogen atom; and Y represents a hydroxy group, a halogen atom, an alkylamino group, a dialkylamino group, an alkenylamino group, a dialkenylamino group, an anilino group (in which the aromatic ring is unsubstituted or has one or two halogen and/or alkyl substituents), a cycloalkylamino group, a 1-pyrrolidinyl group, a piperidino group, a morpholino group, a group of formulan (in which R 4 represents an alkyl group or a phenyl group) or a group of formulan (in which A, R 1 , R 2 and R 3 are as defined above) are useful agricultural fungicides having greater systemic activity and chemical stability than known compounds of similar structure. They may be applied as such or in a conventional preparation to seeds and growing plants. They may be prepared by reacting a 6-(substituted phenyl)-3(2H)-pyridazinone with formaldehyde and optionally with a halogenating agent, an appropriate amine or piperazine. |