Captan properties

At the time of the discovery of captan (except perhaps where sulfur was in an oxidized state), very little was known about the nature and properties of this bond in organic structures. Even today, compilations of bond energies or bond distances or spectroscopic properties fail to include data for organic chemical... 

Similar analysis can be made regarding the protection of the coffee plant and fruit. Here the activity of Difolatan plus its resistance to hydrolysis and greater persistence provides the more ideal combination of properties. Therefore, under the tropical, moist conditions of Kenya, Brazil, Central America and South India, particularly for Colletrichium infections, Phaltan and captan are mediocre and Difolatan is excellent. Incidentally, none of these compounds are systemic and the residue is entirely on the fruit, not on the bean. 

Most fungicides developed for plant disease control before 1965 are multisite biochemical inhibitors that lack the chemical properties and biological specificity required for internal therapeutic action in higher plants. This group of plant protectants include such compounds as the Inorganic copper fungicides, captan, chlorothalonil, dithiocarbamates and chlorinated quinones. 

---