HETEROCYCLIC COMPOUND

1. 2,4-Dioxopyrrolo[2,3-c]pyrroles which in one of their tautomeric forms conform to the formula see diagramm : EP0217214,P20,F13 in which R1 , R2 signify phenyl, biphenylyl, naphthyl or a heterocyclic aromatic radical, which contains 1, 2, 3 or 4 five-, six- or seven-membered rings of which at least one contains 1, 2 or 3 hetero atoms from the series N, O, S, and wherein, the radicals mentioned for R1 , R2 can be substituted by halogen, -CN, -R5 , OR6 , SR6 , -N(R7 )(R8 ), -COOR9 , -N(R10 )COR9 , -N(R6 )COOR9 , N(R6 )CON(R7 )(R8 ), -NHSO2 R9 , -SO2 R9 , -SOR9 , -SO2 OR9 , -CON(R7 )(R8 ), -SO2 N(R7 )(R8 ), -N=N-R11 , -OCOR9 and -OCONHR9 , R3 , R4 stand for hydrogen, C2 -C18 -alkenyl and C2 -C18 - alkynyl, which can each be substituted by halogen, -CN, -OCOR9 , -OR7 , -COOR9 , -SR7 , -CON(R7 )(R8 ) and -OCONHR9 , epoxyethyl, phenyl and naphthyl, which can each be substituted by F, Cl, -Br, -NO2 , -CN, -CF3 , C1 -C18 -alkyl, C1 -C18 -alkoxy, phenyl, phenoxy, C1 -C6 -alkoxycarbonyl and phenoxycarbonyl, -R5 , -COR6 , -CON(R7 )(R8 ), see diagramm : EP0217214,P21,F1 or a radical of the formula see diagramm : EP0217214,P21,F2 and R5 signifies C1 -C18 -alkyl or C3 -C7 -cycloalkyl which can each be substituted by halogen, -CN, -OCOR9 , -OR7 , -COOR9 , -SR7 , -CON(R7 )(R8 ) and -OCONHR9 , R6 , R7 , R8 signify hydrogen, C1 -C18 -alkyl, cyclopentyl and cyclohexyl which can each be substituted by Cl, Br, F, -CN, -OH, mono C1 -C4 -alkylamino, di-C1 -C4 -alkylamino, optionally Cl-, Br-, F-, C1 -C6 -alkyl-or C1 -C6 -alkoxy-substituted phenyl or naphthyl, or by heterocyclic aromatic radicals of a 5- or 6-membered heterocyclic ring system which incorporates 1 or 2 hetero atoms from the series O, N, S and onto which a benzene ring can be fused, phenyl, naphthyl, phenyl-C1 -C4 -alkyl and naphthyl-C1 -C4 -alkyl which can each be substituted by Cl, Br, F, C1 -C18 -alkyl or C1 -C18 -alkoxy, the radical of a 5- or 6-membered heterocyclic ring which incorporates 1, 2 or 3 hetero atoms from the series O, N, S and onto which a benzene ring can be fused, or R7 and R8 in the group -CON(R7 )(R8 ) together with inclusion of the N atom form a 5- or 6-membered heterocyclic ring, R9 signifies C1 -C18 -alkyl, cyclopentyl, cyclohexyl, phenyl-C1 -C4 -alkyl, naphthyl-C1 -C4 -alkyl, phenyl, naphthyl, or the radical of a 5- or 6-membered heterocyclic ring which incorporates 1, 2 or 3 hetero atoms from the series O, N, S and onto which a benzene ring can be fused, it being possible for the radica