Guanidines release

Sulfenamide accelerators generally requite less fatty acid because they release an amine during the vulcanization process which acts to solubilize the zinc. Guanidines and similar amine accelerators also serve to both activate and accelerate vulcanization. 

In addition to the mechanism involving cycHc AMP, nonsugar sweeteners, eg, saccharin and a guanidine-type sweetener, have been found to enhance the production of another second messenger, inositol 1,4,5-trisphosphate (IP3), causing the closure of potassium channels and the release of... 

The baking process has remained much the same until the present day at a stoichiometric ratio of 1 4, phthalic anhydride or phthalic acid reacts with an ammonia releasing compound. The reaction may also start from other suitable materials, such as phthalic acid derivatives, including phthalic acid esters, phthalic acid diamide, or phthalimide. Appropriate ammonia releasing agents include urea and its derivatives, such as biuret, guanidine, and dicyanodiamide. The fact that a certain amount of urea decomposes to form side products makes it necessary to use excess urea. Approximately 0.2 to 0.5, preferably 0.25 equivalents of copper salt should be added for each mole of phthalic anhydride. 0.1 to 0.4 moles of molybdenum salt per mole of phthalic anhydride is sufficient. The reaction temperature is between 200 and 300°C. 

Chemical/Physical. Releases very toxic fumes of chlorides and nitrogen oxides when heated to decomposition (Sax and Lewis, 1987). Reacts with alcoholic sodium sulfite solutions and ammonia to give methanetrisulfonic acid and guanidine, respectively (Sittig, 1985). 

Guanidine hydrochloride is the drug of choice in the management of patients with myasthenic syndrome and may be of use in the treatment ofbotulinum intoxication. Its ability to enhance transmitter release may involve a block of K+ channels and prolongation of the nerve action potential. 

Shieldings observed for the o- and p- N-phenyl ring carbons in cyclic guanidines are attributed to a ( + )-M electron releasing effect of the imino nitrogen. This indicates an N-phenylimino rather than the tautomeric N-phenylamino compound [348] (bottom of page 241). 

After sulfo-NHS-SS-biotin-modified molecules are allowed to interact with avidin or streptavidin probes, the formed complexes can be cleaved at the disulfide bridge by treatment with 50 mM DTT. Reduction releases the biotinylated component from the avidin or streptavidin detection reagent. The use of disulfide biotinylation reagents thus provides much gentler conditions to break the complex than would be required if the avidin-biotin interaction itself were disrupted (which dissociates only at 6—8 M guanidine, pH 1.5). 

An important dGuo oxidation product is imidazolone (Iz), which decomposes into oxazolone (Z) and/or its ring-open guanodino acid form (Ravanat et al. 1991 Raoul et al. 1996 Gasparutto et al. 1999 for kinetic data see Table 10.5). At high pH, these compounds release guanidine for which an assay is available (Kobayashi et al. 1987) (Chap 13.3). 

Hypoglycemic natural products comprise flavonoids, xanthones, triterpenoids, glycosides, alkyldisulfides, aminobutyric acid derivatives, guanidine, polysaccharides, and peptides (see Wang and Ng, 1999). The mechanisms of actions of these hypoglycemic plants are uncertain. They either enhance the release of insulin or enhance the peripheral utilization of glucose. 

The strong binding between biotin and strept(avidin) is a disadvantage when a captured biotin or biotinylated molecule needs to be released. Release usually requires harsh conditions such as 6 M guanidine hydrochloride, pH 1.5... 

The indole linker 1.11 (68), easily prepared from aminomethyl PS resin and N-carboxyalkylated indole-3-carboxaldehyde, was used to support amines and to transform them on SP, obtaining, by release with TFA-DCM 1/1 in 30 min, a variety of compounds, including amides, sulfonamides, guanidines, ureas, and carbamates. 

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