This refers to ditiinopiridazinona Derivatives, processes for their preparation, to their use for Combating unwanted Microorganisms, particularly in phytopathogenic fungi, Plant Protection, and in the domestic Field of Hygiene and Protection of Materials, co Mo to plant protection products containing these ditiinopiridazinona.Claim 1: ditiinopiridazinona Derivatives of formula (1) wherein R1 and R2 simultaneously and jointly represent the cyano Group (- C = o) - N - (R4) n = CH, the compounds of formula (1) contains a Second Ring of pyridazinone； R3 and R4 are equal or different and represent Hydrogen, alkyl C1 - 8 eventually replaced one or more times with Halogen- OR5 or - cor6； alkoxyl alkyl C1 C1 - 8 - 8 - 8 - Man, haloalcoxilo C1, C1 haloalquil - 8 - Uncle c1-4 alkyl, dialkyl amino - 4 - amino -, C1, C3 - 7 cycloalkyl phenylsulfonylamino； eventually replaced one or more times with c1-4 alkyl or Halogen haloalquilo c1-4 aryl, heteroaryl or arylalkyl c1-4, heter Oarilalquilo c1-4 eventually respectively replaced one or more times with HalogenHaloalquilo c1-4 alkyl, alkoxyl C1 C1 - 4 - 4 or - cor6； R5 is Hydrogen, c1-4 alkyl, c1-4 alkyl - or aryl carbonyl； eventually replaced one or more times with c1-4 alkyl or Halogen, haloalquilo c1-4, R6 represents c1-4 alkyl hydroxyl, or alkoxyl c1-4； in which, when R1 and R2 (a) are both Ciano, R3 represents Hydrogen or alkyl not C1 - 8 but not replaced(b) the group or aryl aryl or arylalkyl in R3 is replaced respectively by at least three times, and in which, when R1 and R2 together represent the Group - C (= o) - N (R4) - n = CH - (c), R3 and R4 are not simultaneously one of the following meanings: Hydrogen, Methyl 2 - carboxieti (- ch2ch2co2h unsubstituted benzyl or phenyl), not replaced.La presente se refiere a derivados de ditiinopiridazinona, a procedimientos para su preparación, a su uso para combatir microorganismos indeseados, particularmente hongos fitopatógenos, en la protección de plantas, en el campo doméstico y
