Carbamates fungicides

Carbamates are substituted esters of carbamic acid (NH2COOH) with aliphatic or aromatic substituents on the oxygen and nitrogen atoms. Carbamate insecticides have an aryl or oxime N-methylcarbamate structure, and their mode of action is based on the inhibition of the enzyme acethylcholine esterase (1). However, this inhibition is reversible, and recovery from sublethal doses occurs rapidly. Some carbamate fungicides have a dithio, bisdithio, or benzimidazole carbamate basic structure, and dithiocarbamate fungicides inhibit the enzyme aldehyde deshydro-genase (2). The herbicides have an /V-alkylthiocarbamate or A-phenylcarbamate structure and interfere with photosynthetic activity or affect meristematic activity or lipid metabolism (3). Representative structures of carbamate pesticides are shown in Fig. 1. 

T Gomyo, M Ozawa, S Kobayashi. Analytical method for determining the total content of methyl benzimidazole carbamate fungicides in water by column switching liquid chromatography mass spectrometry. Anal Sci 8 687-690, 1992. 

Ethylenediamine is used to produce chelating agents and carbamate fungicides. Monoethanolamine (MEA), reacts with ammonia and hydrogen to produce ethylenediamine. The reaction occurs in the gas phase over a catalyst at temperatures < 300 "C (572 F) and pressiues > 250 bar (246.7 atm) [12]. Other details of the process are proprietary. The products are ... 

Figure 5.10 Fungicides. Benlate contains the carbamate fungicide benomyl. Kocide 101 contains copper hydroxide, which is an inorganic copper containing fungicide.

Selenium diethyldithio-carbamate Fungicide vulcanizing agent... 

Shukla Y, Antony M, Kumar S, et al. 1990. Carcinogenic activity of a carbamate fungicide, mancozeb, on mouse skin. Cancer Lett 53 191-195. 

Recently, the carbamate fungicide diethofencarb (15) which takes advantage of a negatively-correlated cross-resistance phenomenon, has been developed as a potent fungicide against benzimidazole-resistant fungi [45, 46]. Studies on the mode of action of 15 have revealed that P-tubulin in the benzimidazole-resistant strain F914 of N. crassa has an affinity for diethofencarb (15) rather than for benzimidazole derivatives, whilst in a wild-type strain of N. crassa there was an inverse affinity [46, 47]. 

Tierney KB, Taylor AL, Ross PS, Kennedy CJ (2006a) The alarm reaction of coho salmon parr is impaired by the carbamate fungicide IPBC. Aquat Toxicol 79 149-157... 

Ludwig, R. A. Thorn, G. D. (1960). Chemistry and mode of action of dithio-carbamate fungicides. Ado. Pest Cont. Res., 3, 219-52. 

Chloroformates are valuable raw materials for a series of crop protection agents. The carbamic fungicide Propamocarh is prepared with n-propyl chloroformate. 

Carbamates (fungicides) Apples RP-HPEC Amperometric (G-PTEE) [166]... 

Carbamate insecticides are often used in conjunction with the synergists commonly employed with pyrethrum (Section 3.4). For further reading on carbamate inseticides, see Street (1975) Weiden and Moorefield (1964). For the carbamate fungicides, see Section 6.4 (p. 218). 

The 2-imino-4-thiazolines may be used as ultraviolet-light stabilizers of polyolefin compositions (1026). 2-Aminothiazole improves adhesive properties of wood to wood glue (271). Cbmpound 428 exhibits antioxidant properties (Scheme 242) (1027). Ammonium N-(2-thiazolyl)dithio-carbamate (429) is a bactericide and fungicide used in industrial products such as lumber, paint, plastics, and textiles (1037). Compound 430 is reported (1038) to form an excellent volume of foam coating in aluminum pans when ignited with propane. 

Aliphatic Isocyanates. Aflphatic diisocyanates have traditionally commanded a premium price because the aflphatic amine precursors ate mote expensive than aromatic diamines. They ate most commonly used in appHcafions which support the added cost or where the long-term performance of aromatic isocyanates is unacceptable. Monofuncfional aflphatic isocyanates, such as methyl and -butyl isocyanate, ate used as intermediates in the production of carbamate-based and urea-based insecticides and fungicides (see Fungicides, agricultural Insectcontroltechnology). 

Pesticide Solvent. The majority of organic fungicides, insecticides, and herbicides (qv) are soluble in DMSO, including such difficult-to-solvate materials as the substituted ureas and carbamates (see Fungicides, agricultural Insect control technology Pesticides). Dimethyl sulfoxide forms cosolvent systems of enhanced solubiUty properties with many solvents (109). 

Carbamates are used as insecticides, nematocides, fungicides, and herbicides the toxicity of carbamate insecticides is similar to that of OP compounds and is based on the inhibition of ACHE. Also, carbamate metabolites may inhibit ACHE but are usually weaker inhibitors than the unchanged compound. Cholinesterase inhibition caused by carbamates is labile, of short duration, and rapidly reversible in fact, the half-life of the inhibited enzymes ranges between some minutes and 2 to 3 hours for RBC-ACHE and is on the order of some minutes for PCHE. Accumulation of cholinesterase activity on repeated exposures, as observed with OP compounds, does not occur with... 

T. Noguer, B. Leca, G. Jeanty, and J.L. Marty, Biosensors based on enzyme inhibition detection of organophosphorus and carbamate insecticides and dithiocarbamate fungicides. Field Anal. Chem. Tech. 3, 171-178 (1999). 

While insect control is more often a limiting factor in tropical bean production, there are several diseases that are serious in certain seasons and locations. Bean rust is one of the most widespread diseases, and it can be controlled effectively with protective fungicides, such as elemental sulfur and certain of the carbamic acid derivatives. The economics of bean production usually preclude any costly applications, however, and the problem has generally been turned over to the plant breeder to solve with resistant varieties. At present, the most practical control of bean anthracnose and the bean blights is through the use of clean seed and resistant varieties. Control with fungicides has always proved difficult and of doubtful value. 

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