Fungicidal Phthalimidophosphonothionates

Abstract

The fungicidal activity, mammalian toxicity, and methods of synthesis of phthalimidophosphonothionates, a novel type of organophosphoramide compound, have been investigated. The findings led to development of the compound diethyl phthalimidophosphonothionate as a new bioproduct. This diester protects a variety of crops from certain plant diseases, such as powdery mildew, apple scab, leaf spot, brown rot, and black spot.

Isolation from sugar beet fruit and characterization of cis-4-cyclohexene-1,2-dicarboximide as a germination inhibitor

“…Captan is very slightly soluble in water, and a water-saturated solution of Captan was not inhibitory in our lettuce seed assay. N substitution by phosphothionates have produced fungicides (Tolkmith et al, 1967). Another group of cyclic imides are the maleimides, of which A-ethylmaleimide has been widely used as an enzyme inhibitor.…”

“…Identity was confirmed by synthesis and comparison of physical and biological properties. Derivatives were synthesized, and the most active structure was the A-butyl analog which inhibited lettuce seed germination at 10~5 m. Inhibition of Dor mancy in plants and seeds may be regulated by many endogenous inhibitors and growth substances (van Overbeek, 1966). Inhibitors of seed germination have been recognized in grain (Miyamoto et al, 1961), fruit (Massart, 1957), tubers (Hemberg, 1949), and buds (Robinson et al, 1963).…”

The development of synthetic fungicides; trends and prospects

“…Dowco 199 (Tolkmith, 1966;Tolkmith et al, 1967c) Of course, Captan or rather Phaltan (or Folpet) is a similar type of compound. But here the fungitoxic part is the group -S-CC13 and the phthalimide part of the molecule serves as a suitable vehiculum.…”