Plant protecting agents

Ethylene chlorohydrin may be used in the manufacture of dye intermediates, pharmaceuticals, plant-protection agents, pesticides, and plastici2ers (3). 

The most important industrial application of alkanesulfonates is the generation of the appropriate emulsions for polymerizing vinyl monomers, e.g., vinyl-chloride or styrene. Other uses are as textile and leather auxiliaries, formulating aids for plant protection agents, and fire-extinguishing foams. 

Substituted 1-hydroxy cyclohexane-1-carboxyhc acids, which could be prepared from the corresponding cyanohydrins by acid hydrolysis as described above, are important as pharmaceuticals and plant-protective agents. Although the compounds derived from 2- and 3-cyclohexanones have two stereogenic centers, stereoselective syntheses of these interesting products have been published only very recently. " Completely unexpected are the results of HNL-catalyzed additions to 4-substituted cyclohexanones, which do not possess a prochiral center. The (R)-PaHNL-catalyzed addition affords almost exclusively fran -isomers, whereas with (5 )-MeHNL cA-addition is favored (Table 4). ... 

Some of the peptide families here have been successfully expressed in standard laboratory bacterial or yeast expression systems. This approach allows the production of larger amounts of peptides not amenable to chemical synthesis and opens the potential of large-scale production for biotechnological uses, for example, as plant protection agent applied externally. 

Aminomethylene)-2-phenyl-5(47/)-oxazolone 418 has been converted to 4-(alkylthiomethylene)-2-phenyl-5(47/)-oxazolones 419 by treatment with carbon disulfide and subsequent alkylation. These 4-(alkylthiomethylene) analogues are useful intermediates for biologically active peptides, pharmaceuticals, and plant-protective agents (Scheme 7.136 Table 7.38, Fig. 

Over the last few decades, safety has become one of the most important topics related to food. From this view, quality control of vegetable raw materials has at first to cover the following issues natural and anthropogenic contaminants (e.g. heavy metals, pollution from industrial and private combustions, not professionally deposited waste products, radionuclides), residues of fertilisers (e.g. nitrate), plant-conditioning and plant-protective agents, filth, pests, the microbial status and the occurrence of microbial toxins. It is not possible to discuss all these aspects in detail however, with a focus on herbs and spices, two of them should be stressed more thoroughly. For further information, see [8]. 

Residues of Plant-Conditioning and Plant-Protective Agents... 

For several reasons, residues of plant-conditioning and plant-protective agents represent a highly complex problem. So is it often not quite clear what to look... 

Another serious problem is the fact that the maximal accepted residues for the different plant-conditioning and plant-protective agents are not harmonised and that, for example, in Germany for some substances the maximum value for residues in herbs and spices is generally set at 0.01 ppm. This value was solely set by a political decision and has no proven toxicological background. Moreover in a number of cases this value is near the lowest detection value of the particular substance. 

Many natural materials contain residues of plant-protection agents which are, understandably not desired owing to their possible effect on human or animal organisms. 

Processes of such kinds can be found in the literature. E. Stahl, et al. [1] describe the decontamination of drugs, in particular, the reduction of pesticides from senna leaves by means of supercritical dry carbon dioxide [2]. The patents EP 0382116 A2 [4] and DE 4342874 Al [5] specify processes to remove non-polar substances from ginseng with dense carbon dioxide, in which the ginseng is moisturized prior to extraction, and the second method also uses an entrainer. The European Patent Application EP 0925724 A2 from NATEX [3] explains a process for the removal of plant-protection agents and/or undesired substances from cereals. 

So far no compound containing the 1,2,3-triazine system has been isolated from natural sources. The most important compound in the 1,2,3-benzotriazine series seems to be the plant protection agent (156) (Bayer 17147, Guthion, Azinphos methyl). There are a very large number of papers and patents dealing with the chemical and biochemical properties of this compound the references up to Chemical Abstracts, volume 81, can be found in the earlier monograph (78HC(33)165). 

Isocyanates (RNCO) are industrially relevant compounds which find application in several fields [9, 106]. Many isocyanates serve as the starting materials for the manufacture of plant protection agents, pesticides, dyes, resins and plastics, textile waterproofing agents, detergents, bleaches, and adhesives. They are also widely used in surface coatings such as paints, sealants and finishes, and in the manufacture of rubbery plastics such as those used to coat wires. Traditionally, diisocyanates are the primary feedstock for the production of polyurethanes. The global market for diisocyanates in the year 2000 was 4.4 million tonnes, of which 61.3% was methylene diphenyl diisocyanate (MDI), 34.1% was toluene diisocyanate... 

He, H., Silo-Suh, L.A., Clardy, I., Handelsman, J. Zwittermycin A, an antifungal and plant protection agent from Bacillus cereus. Tetrahedron Lett 1994 35 2499-502. 

At Chevron and elsewhere a whole series of copper, zinc, manganese, calcium, cadmium, lead and arsenic salts were manufactured as plant protection agents and micronutrients by the carefully pH controlled precipitation of insolubles where the active cation or anion could only reach a small, plant-tolerable, maximum concentration. In such cases this maximum could be calculated... 

Stockholm Convention This bans the production and use of certain Persistent Organic Pollutants (POPs) or severely restricts release. It applies to plant protection agents, industral chemicals and highly toxic by-products and incineration processes, such as dioxins and furans. 

Figure 1.5 Examples of plant-protecting agents containing fluorine...

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