Secondary compound

Primary halides are more reactive than secondary compounds quaternary salt formation does not occur with tertiary halides, elimination always occurring to give the hydriodide and an olefln, Also, the larger the alkyl group the slower is the reaction this is shown by the very slow reaction of dodecyl bromide with quinoline, and even butyl iodide is much slower to react than methyl iodide. The longer chain primary halides commonly undergo elimination rather than cause quaternization for example, n-octyl and cetyl iodides give only the hydriodides when heated with 9-aminoacridine. ... 

Primary aliphatic nitro compounds can be reduced to nitriles with sodium dihydro(trithio)borate " or with f-BuN=C/BuN=C=0. Secondary compounds give mostly ketones (e.g., nitrocyclohexane gave 45% cyclohexanone, 30% cyclohexanone oxime, and 19% A-cyclohexylhydroxylamine). Tertiary aliphatic nitro compounds do not react with this reagent. See also 19-41. 

Tissue AOPP Cone. (mM) Growth reduction (%) Secondary compound and % reduction Reference ... 

Chemical manipulation of secondary compound composition of crop plants offers several advantages over genetic control of their production. Chemical manipulation allows for timing the manipulation as well as possibly determining the quality and quantity of the desired response. 

There are numerous reports of allelopathy in the literature, but often the identity of the allelochemical(s) is unknown. There are, however, many cases where specific compounds or groups of compounds have been implicated as allelopathic agents. Table 1 summarizes some examples of sources and identities of allelochemicals that directly inhibit plant growth. These secondary compounds have been implicated as a driving force in ecological succession ( 1 ). 

Fester, T., W. Maier et al. (1999). Accumulation of secondary compounds in barley and wheat roots in response to inoculation with an arbuscular mycorrhizal fungus and co-inoculation with rhizosphere bacteria. Mycorrhiza 8(5) 241-246. 

Plant resins are lipid-soluble mixtures of volatile and nonvolatile terpenoid and/or phenolic secondary compounds that are usually secreted in specialized structures located either internally or on the surface of the plant. Although terpenoid resins constitute the majority of the resins produced and used, some other important resins are phenolic. Phenolic resin components, which occur on the surfaces of plant organs, have been used particularly in medicines [86]. 

Plant-derived insecticides, 14 338-339 Plant-derived secondary compounds, 13 357... 

McKey D (1974) Adaptive patterns in alkaloid physiology. Am Nat 108 305-320 McKey D (1979) The distribution of secondary compounds within plants. In Rosenthal GA, Janzen DH (eds) Herbivores their interactions with plant secondary metabolites. Academic, New York, pp 55-133... 

Cornell HV, Hawkins BA (2003) Herbivore responses to plant secondary compounds a test of phytochemical coevolution theory. Am Nat 161 507-522 Cronin G (2001) Resource allocation in seaweeds and marine invertebrates chemical defense patterns in relation to defense theories. In McClintock JB, Baker BJ (eds) Mar Chem Ecol. CRC, Boca Raton, FL, pp 325-354... 

Freeland WJ, Janzen DH (1974) Strategies in herbivory by mammals the role of plant secondary compounds. Am Nat 108 269-289... 

Secondary compounds produced by plants may have other significant survival roles, such as signals to attract insects, birds, or other animals to enhance pollination or seed dispersal. In addition to any potential functions, secondary compounds may concomitantly serve a physiologic function, such as protection against ultraviolet (UV) light or frost, or provide a function in nitrogen transport and storage. In several instances, compounds can serve multiple functions in the same plant. Anthocyanins or monoterpenes can be... 

Over 100,000 secondary compounds have been identified, and categorized into one of two major classes ... 

For thousands of years, people have used some of these compounds as fiavors, dyes, fragrances, insecticides, hallucinogens, nutritional supplements, animal or human poisons, and therapeutic or pharmaceutical agents. While secondary compounds are an evolutionary adaptation in plants, they serve multiple functions for mankind. 

The effect of phosphate on alkaloid production has also been evaluated (138). Using a modified induction medium devoid of phosphate and other essential growth factors, production of secondary compounds was more rapid than when phosphate was present. A broader study of the phenomenon has been reported by a French group (139) where, using three alkaloids as markers, the disappearance of the major nutrients from the medium and the evolution of phosphates, nitrates, ammonium ions, glucose, and starch in the cells were observed over time. It was not possible to relate alkaloid accumulation to the appearance or disappearance of any one metabolite in particular. However, other workers have found that the rate of biomass accumulation was directly related to the rate of formation of cellular serpentine (40) (140). 

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