Microbiocidal heterobicyclic derivatives

A compound of formula I:

• wherein
• each of A1, A2, and A3 independently represents a nitrogen atom or CR7;
• Y—X represents a radical selected from G1, G2, G3 and G4:
• R1 and R2 are each independently selected from hydrogen, halogen, cyano, C1-C6 alkyl, C3-C7 cycloalkyl, C2-C6 alkenyl, C2-C6 alkynyl, in which the alkyl, cycloalkyl, alkenyl and alkynyl groups may be optionally substituted with 1 to 3 substituents independently selected from halogen, C1-C6 alkoxy, C1-C6 alkylthio and phenoxy;
• or
• R1 and R2 together with the carbon atom to which they are attached represent a C3-C10 cycloalkyl group (which may be optionally substituted with 1 to 3 substituents independently selected from the group consisting of halogen, C1-C6 alkyl, C1-C6 alkoxy and phenoxy);
• R3 and R4 are each independently selected from hydrogen, halogen, hydroxyl, C1-C6 alkyl, C1-C6 alkoxy, C3-C7 cycloalkyl, C2-C6 alkenyl, C2-C6 alkynyl, in which the alkyl, alkoxy, cycloalkyl, alkenyl and alkynyl groups may be optionally substituted with 1 to 3 substituents independently selected from halogen, C1-C6 alkoxy, C1-C6 alkylthio and phenoxy;
• or
• R3 and R4 together with the carbon atom to which they are attached represent C═O, C═CH2 or C3-C10 cycloalkyl (which may be optionally substituted with 1 to 3 substituents independently selected from the group consisting of a halogen, C1-C6 alkyl, C1-C6 alkoxy and phenoxy);
• R5 is hydrogen, halogen, C1-C6 alkyl, C1-C6 alkoxy or hydroxyl;
• R6 is hydrogen, halogen, C1-C6 alkyl, C1-C6 alkoxy or hydroxyl;
• each R7 independently represents hydrogen, cyano, halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C3-C7 cycloalkyl, C2-C6 alkynyl, or hydroxyl;
• each R8 independently represents hydroxyl, halogen, cyano, amino, C1-C6 alkyl, C2-C6 alkenyl, C3-C7 cycloalkyl, C2-C6 alkenyloxy, C3-C6 alkynyloxy, C1-C6 alkylthio, C2-C6 alkynyl, C1-C6 alkoxy, C1-C6 alkylcarbonyl, NH(C1-C6 alkyl), N(C1-C6 alkyl)2, CO2H, CO2(C1-C6 alkyl), C(O)N(C1-C6 alkyl)2, C(O)NH(C1-C6 alkyl), C(O)NH2, NH(C1-C6 alkylcarbonyl), N(C1-C6 alkylcarbonyl)2, aryl, heteroraryl, aryloxy or heteroraryloxy, in which the alkyl, cycloalkyl, alkenyl, alkynyl, alkoxy groups may be optionally substituted with 1 to 3 substituents independently selected from the group consisting of halogen, C1-C6 alkoxy, hydroxyl, C1-C6 alkylthio, C1-C6 alkoxycarbonyl and phenoxy, and the aryl or heteroaryl groups may be optionally substituted with 1 to 5 substituents independently selected from the group consisting of halogen, C1-C6 alkyl (which itself may be optionally substituted with 1 to 3 halogen atoms), C1-C6 alkoxy, amino (which itself may be substituted with 1 or 2 groups independently selected from C1-C6 alkyl, C1-C6 alkylcarbonyl), nitro, cyano, hydroxyl, mercapto and C1-C6 alkylthio;
• n is 0, 1, 2, 3 or 4;
• Ra is hydrogen, C1-C6 alkylcarbonyl or C1-C6 alkyl, which may be optionally substituted with 1 to 3 substituents independently selected from the group consisting of halogen, C1-C6 alkoxy, C1-C6 alkylthio and phenoxy;
• or a salt or N-oxide thereof.