A compound according to Formula I: ** Formula ** wherein R1 is: H； C1-C6 alkyl optionally substituted by 1-3 R4； C1-C6 alkenyl optionally substituted by 1-3 R4； C3-C6 alkynyl optionally substituted by 1-3 R4； phenyl or benzyl, wherein each of phenyl or benzyl may optionally be substituted with 1-3 R5, or with a 5-6 membered saturated or unsaturated ring system, or with a 5-6 membered fused ring system, or with a system of fused rings of 6-6 members, each containing 1-3 heteroatoms where each ring can be optionally substituted by 1-3 R5, biphenyl or naphthyl optionally substituted by 1-3 R5； - (CHR6) mOR7； -C (>； = O) R8； -C (>； = S) R8； -C (>； = O) OR8； -C (>； = S) OR8； - (CHR6) m N (R9) R10； -C (>； = O) N (R9) R10； or -C (>； = S) N (R9) R10； where m is an integer from 1 to 3； R2 is H or C1-C6 alkyl optionally substituted by R4； Alternatively, R1 and R2 can be taken together to form>； = CR11N (R12) R13； R3 is -C (>； = O) N (R9) R10 or -C (>； = S) N (R9) R10； R4 is independently halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C1-C4 alkylthio, C1-C4 haloalkylthio, halotium, amino, C1-C3 alkylamino, C2-C6 alkoxycarbonyl, alkylcarbonyl C2-C6, C2-C6 alkylaminocarbonyl, hydroxyl, or C3-C6 trialkylsilyl； R5 is independently halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C1-C6 alkylthio, C1-C6 haloalkylthio, halotium, amino, C1-C6 alkylamino, C2-C6 dialkylamino, alkoxycarbonyl C2-C6, or C2-C6 alkylcarbonyl, nitro, hydroxyl, or cyano； R6 is H, C1-C6 alkyl, C1-C6 alkoxy, benzyl or phenyl, wherein each of benzyl or phenyl may optionally be substituted with 1-3 R5； R7 is H, C1-C6 alkyl, C2-C6 alkenyl, C3-C6 alkynyl, C1-C6 haloalkyl, C1-C6 alkoxyalkyl, C2-C6 alkylcarbonyl, phenyl or benzyl, wherein each of benzyl or phenyl can optionally be substituted for 1-3 R5, or with a system of saturated or unsaturated rings of 5-6 members, or with a system of fused rings of 5-6 members, or with a system of fused rings of 6-6
