Fungicides of formamide type

The fungicidal action of formeldehyde is based on its reaction with the amino groups of the spore protoplasm, that is, it denatures proteins. 

Several fungicides with contact action were also discovered among the derivatives of aldehydes however, the agricultural use of compounds of this type began only when active substances with systemic action were found among them. 

Chloraniformethan (1), introduced under the trade name Imugan , is one of these important fungicides. Its chemical composition is N-[2,2,2-trichloro-I-(3,4-dichloroaniIine)ethyl]formamide. Synthesis starts with chloral (2), which, in reaction with formamide (3) gives chloral-formamide [(2,2,2-trichloro-l-hydroxyethyl) formamide] (4). This reacts with 3,4-dichlorophenyl isocyanate (5) via the formation of the carbamic acid ester (6) as intermediate, to yield, after rapid carbon dioxide elminiation, the end-product (1) (Malz et ai, 1966., Dorker and Schrader, 1963), 

Chloraniformethan is a fungicide with systemic action effective against powdery mildew fungi and particularly to fungi pests of cereals (Davis et ai, 1971). It is not toxic to mammals, acute oral for rats being over 2500 mg/kg. 

Another powerful active substance of formamide type is triforine 1,1 -piperazine- 

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