Cyanogenic mechanism

Cyenogenic Mechanism. The acute toxicity of a third class of simple nonelectrolytes can be readily rationalized in terms of a cyanogenic mechanism, involving metabolic release of cyanide. Free cyanide is highly toxic to fish with a TLm of 0.69 mg/L (93). Some examples of cyanogenic toxicants are shown in Table IV. Lactonitrile is... 

Naturally occurring compounds called cyanogenic glycosides, such as lotau-stralin, release hydrogen cyanide, HCN, when treated with aqueous acid. The reaction occurs by hydrolysis of the acetal linkage to form a cyanohydrin, which then expels HCN and gives a carbonyl compound-fa) Show the mechanism of the acetal hydrolysis and the structure of the cyanohydrin that results. 

A. Preparation of Cuprous Cyanide. (Note i)—In a 6-1. round-bottom flask fitted with a stopper carrying a mechanical stirrer, a separatory funnel, and a gas exit tube leading to a good hood (Note 2), is placed a solution of 650 g. (2.6 moles) of crystallized copper sulfate in 4 1. of water. The flask is surrounded by an oil bath and heated to about 8o°. The stirrer is started and a solution of 255 g. (5.2 moles) of sodium cyanide (Note 3) in 650 cc. of water is added from the separatory funnel over a period of about one-half hour. Then the mixture is boiled until no more cyanogen gas is evolved. This requires about five to ten minutes. 

Na C, TM Olson (2006) Mechanism and kinetics of cyanogen chloride formation from the chlorination of glycine. Environ Sci Technol 40 1469-1477. 

The solid explodes when mechanically shocked or heated in a closed vessel [1], Preparative methods are hazardous because of the need to heat the explosive precursor, cyanogen azide [1,2]. 

Kohn, J., and Wilchek, M. (1982) Mechanism of activation of Sepharose and Sephadex by cyanogen bromide. Enzyme Microb. Technol. 4, 161-163. 

Figure 3. Two hypothetical mechanisms by which Heliconlus may protect itself from toxification by Passiflora cyanogenic glycosides.

Also, in the halogenation of XXb with cyanogen bromide the predominate product was the nortricyclenic bromide (XXIIIa and b, X = Br) the treatment of XXIa with iodine monochloride yields the endo-nortricyclenic iodide (XXIIIa, X = I). Thus the mechanism appears to involve attack of a positive halogen with predominate retention of configuration at carbon. 

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