Development as fungicide

Other 1,2,4-triazole containing tertiary alcohols are being developed as fungicides, and it is likely that further compounds from this family, with useful biological properties, will be discovered. 

Dithiocarbamates can also be prepared from diamines. For example, as early as 1872, Hofmann (97) reported the reaction of carbon disulfide with 1,2-diaminoethane. Later in the 1960s, addition of 2 equiv of sodium hydroxide and carbon disulfide to 1,2-diaminoethane was shown to afford the bis(dithiocarba-mate) compound in an exothermic reaction (98-102) 1,6-diaminohexane behaving in a similar manner (98). A wide range of polymeric transition metal complexes have been prepared using these salts (98). All are insoluble in water and common organic solvents, and some examples have been developed as fungicides (14, 31). 

III of mitochondrial respiration.14 The compounds exhibited good broad-spectrum activity in vitro, comparable with synthetic standards, but in vivo was inadequate to justify further development as a fungicidal product. Further study showed that activity was lost due to photolytic instability, and led to the production (Figure 4.24) of a series of analogues and selection of the eventual product candidates kresoxim-methyl (BAS 490 F)15 and azoxystrobin (ICIA5504).16... 

Derivatives of 2,3-dihydro-l,4-oxathiin and 1,4-benzoxathiins have been patented as agrochemicals. An important development in fungicidal research has been the discovery of so-called systemic fungicides. Unlike surface fungicides which may require repeated... 

Silylmethyltriazoles represent a new, highly active class of triazole fungicides, whose success in a wide variety of crops and climatic conditions confirms the utility of organosilicon compounds as agrichemicals. This paper describes their discovery, synthesis, and structure-activity relationships. Based on the results of worldwide field evaluations, some of which are presented, a member of this class, DPX-H6573, is being developed as a broad spectrum foliar fungicide. 

Tests such as these, along with extensive field evaluation worldwide, led to the selection of DPX-H6573 for development as a foliar fungicide. 

An example of the simultaneous anti-powdery mildew and acaricidal action is the biological effect of 6-methyl-2,3-quinoxalinedithiol cyclic carbonate (oxythio-quinox, 30) and of the related 2,3-quinoxalinediyl cyclic trithiocarbonate (thioquinox, 31), introduced originally as fungicides against powdery mildew and discussed already under the heading fungicides. These compounds were developed by research workers of the Bayer Co. in the course of their study of the acylated derivatives of 2,3-dimercaptoquinoxaline (Sasse et ai, 1958 19 Basse, 1960). 

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