Abstract: Compounds of Formula I, and their N-oxides and agriculturally suitable salts, are disclosed which are useful for controlling undesired vegetation wherein R1 is cyclopropyl optionally substituted with 1-5 R5, isopropyl optionally substituted with 1-5 R6, or phenyl optionally substituted with 1-3 R7; R2 is ((O)jC(R15)(R16))kR; R is CO2H or a herbicidally effective derivative of CO2H; R3 is halogen, cyano, nitro, OR20, SR21 or N(R22)R23; R4 is —N(R24)R25 or —NO2; j is 0 or 1; and k is 0 or 1; provided that when k is 0, then j is 0; and R5, R6, R7, R15, R16, R20, R21, R22, R23, R24 and R25 are as defined in the disclosure. Also disclosed are compositions comprising the compounds of Formula I and a method for controlling undesired vegetation which involves contacting the vegetation or its environment with an effective amount of a compound of Formula I.

Abstract: Compounds of Formula I, and their N-oxides and agriculturally suitable salts, are disclosed which are useful for controlling undesired vegetation wherein R1 is cyclopropyl optionally substituted with 1-5 R5, isopropyl optionally substituted with 1-5 R6, or phenyl optionally substituted with 1-3 R7; R2 is ((O)jC(R15)(R16))kR; R is CO2H or a herbicidally effective derivative of CO2H; R3 is halogen, cyano, nitro, OR20, SR21 or N(R22)R23; R4 is —N(R24)R25 or —NO2; j is 0 or 1; and k is 0 or 1; provided that when k is 0, then j is 0; and R5, R6, R7, R15, R16, R20, R21, R22, R23, R24 and R25 are as defined in the disclosure. Also disclosed are compositions comprising the compounds of Formula I and a method for controlling undesired vegetation which involves contacting the vegetation or its environment with an effective amount of a compound of Formula I.

Abstract: Compounds of Formula I, and their N-oxides and agriculturally suitable salts, are disclosed which are useful for controlling undesired vegetation wherein R1 is cyclopropyl optionally substituted with 1-5 R5, isopropyl optionally substituted with 1-5 R6, or phenyl optionally substituted with 1-3 R7; R2 is ((O)jC(R15)(R16))kR; R is CO2H or a herbicidally effective derivative of CO2H; R3 is halogen, cyano, nitro, OR20, SR21 or N(R22)R23; R4 is —N(R24)R25 or —NO2; j is 0 or 1; and k is 0 or 1; provided that when k is 0, then j is 0; and R5, R6, R7, R15, R16, R20, R21, R22, R23, R24 and R25 are as defined in the disclosure. Also disclosed are compositions comprising the compounds of Formula I and a method for controlling undesired vegetation which involves contacting the vegetation or its environment with an effective amount of a compound of Formula I.

Abstract: Compounds of Formula I, and their N-oxides and agriculturally suitable salts, are disclosed which are useful for controlling undesired vegetation wherein R1 is cyclopropyl optionally substituted with 1-5 R5, isopropyl optionally substituted with 1-5 R6, or phenyl optionally substituted with 1-3 R7; R2 is ((O)jC(R15)(R16))kR; R is CO2H or a herbicidally effective derivative of CO2H; R3 is halogen, cyano, nitro, OR20, SR21 or N(R22)R23; R4 is —N(R24)R25 or —NO2; j is 0 or 1; and k is 0 or 1; provided that when k is 0, then j is 0; and R5, R6, R7, R15, R16, R20, R21, R22, R23, R24 and R25 are as defined in the disclosure. Also disclosed are compositions comprising the compounds of Formula I and a method for controlling undesired vegetation which involves contacting the vegetation or its environment with an effective amount of a compound of Formula I.

Abstract: Compounds of Formula I, and their N-oxides and agriculturally suitable salts, are disclosed which are useful for controlling undesired vegetation wherein R1 is cyclopropyl optionally substituted with 1-5 R5, isopropyl optionally substituted with 1-5 R6, or phenyl optionally substituted with 1-3 R7; R2 is ((O)jC(R15)(R16))kR; R is CO2H or a herbicidally effective derivative of CO2H; R3 is halogen, cyano, nitro, OR20, SR21 or N(R22)R23; R4 is —N(R24)R25 or —NO2; j is 0 or 1; and k is 0 or 1; provided that when k is 0, then j is 0; and R5, R6, R7, R15, R16, R20, R21, R22, R23, R24 and R25 are as defined in the disclosure. Also disclosed are compositions comprising the compounds of Formula I and a method for controlling undesired vegetation which involves contacting the vegetation or its environment with an effective amount of a compound of Formula I.

Abstract: The invention relates to the isolation and modification of nucleic acid sequences encoding p-hydroxyphenylpyruvate dioxygenase enzyme from plants. These nucleic acid sequences were used to establish methods of identification of new herbicidal compounds that inhibit the activity of this enzyme, and to prepare new crop plants that are tolerant to the herbicidal action of inhibitors this enzyme. Chimeric genes comprising nucleic acid fragments containing all or part of the nucleic acid sequences encoding p-hydroxyphenylpyruvate dioxygenase may be used to produce active plant p-hydroxyphenylpyruvate dioxygenase enzyme in microorganisms, and to cause the production of modified forms of the enzyme in plants that may render such plants tolerant to inhibitors of the enzyme.