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Reaction nicotinic

Serious reactions nicotine dependence, fetal harm risk. [Pg.486]

Section 15 11 Oxidation of alcohols to aldehydes and ketones is a common biological reaction Most require a coenzyme such as the oxidized form of nicotin amide adenine dmucleotide (NAD" )... [Pg.655]

The Kixnig reaction (Fig. 5) has been used to determine the amount of nicotinic acid and niacinamide. In this procedure, quatemization of the pyridine nucleus by cyanogen bromide is followed by ring opening to generate the putative dialdehyde intermediate. Reaction of this compound with an appropriate base, such as p-rr ethyl am in oph en o1 sulfate (47) or sulfanilic acid (48), generates a dye. The concentration of this dye is deterrnined c olo rime trie ally. [Pg.50]

In the case of nicotinamide, the color yield is often low. This problem can be circumvented by either hydrolysis to nicotinic acid or by conversion of the amide to a fluorescent compound. Treatment of nicotinamide with methyl iodide yields the quaternary ammonium salt, /V-methyl nicotinamide (5). Reaction of this compound with acetophenone yields a fluorescent adduct (49). Other carbonyl compounds have also been used (50—54). [Pg.51]

For more specific analysis, chromatographic methods have been developed. Using reverse-phase columns and uv detection, hplc methods have been appHed to the analysis of nicotinic acid and nicotinamide in biological fluids such as blood and urine and in foods such as coffee and meat. Derivatization techniques have also been employed to improve sensitivity (55). For example, the reaction of nicotinic amide with DCCI (AT-dicyclohexyl-0-methoxycoumarin-4-yl)methyl isourea to yield the fluorescent coumarin ester has been reported (56). After separation on a reversed-phase column, detection limits of 10 pmol for nicotinic acid have been reported (57). [Pg.51]

Owing to poor volatihty, derivatization of nicotinic acid and nicotinamide are important techniques in the gc analysis of these substances. For example, a gc procedure has been reported for nicotinamide using a flame ionisation detector at detection limits of - 0.2 fig (58). The nonvolatile amide was converted to the nitrile by reaction with heptafluorobutryic anhydride (56). For a related molecule, quinolinic acid, fmol detection limits were claimed for a gc procedure using either packed or capillary columns after derivatization to its hexafluoroisopropyl ester (58). [Pg.51]

Ethers, esters, amides and imidazolidines containing an epithio group are said to be effective in enhancing the antiwear and extreme pressure peiformance of lubricants. Other uses of thiiranes are as follows fuel gas odorant (2-methylthiirane), improvement of antistatic and wetting properties of fibers and films [poly(ethyleneglycol) ethers of 2-hydroxymethyl thiirane], inhibition of alkene metathesis (2-methylthiirane), stabilizers for poly(thiirane) (halogen adducts of thiiranes), enhancement of respiration of tobacco leaves (thiirane), tobacco additives to reduce nicotine and to reduce phenol levels in smoke [2-(methoxymethyl)thiirane], stabilizers for trichloroethylene and 1,1,1-trichloroethane (2-methylthiirane, 2-hydroxymethylthiirane) and stabilizers for organic compounds (0,0-dialkyldithiophosphate esters of 2-mercaptomethylthiirane). The product of the reaction of aniline with thiirane is reported to be useful in the flotation of zinc sulfide. [Pg.184]

Other, closely related, nicotinic acid derivatives and the unsubstituted system itself have also been studied and undergo similar reactions. Moreover, the approach may be extended to 2,2 -bipyridyls. Newkome and his collaborators have used the 2,2 -bipyridyl unit 19) as an electrophile in which ortho-hr ommes served as leaving groups. They have also used halomethyl systems and formed the macrocycles from these systems . A compound derived from the latter starting material 20) is reported to form a cobalt complex, in which both nitrogens and only one of the oxygen atoms participate in the binding . The two precursor units are shown below as 79 and 20, respectively. [Pg.45]

The objection that Formula (A) for nicotine does not provide for the benzoyl derivative of nicotine obtained by fitard was overcome when Pinner 35 showed that in this reaction the pyrrolidine ring is opened, giving rise to metonicotine (isonieotine), and that the supposed benzoylnieotine is benzoylwietanieotine,... [Pg.39]

Colour Reactions. Rochelmeyer (1939) has provided a list of colour reactions given by solasodine and solasodiene (solanosodine), with reagents usually applied to the sterols, and Briggs et al. have found that when concentrated sulphuric acid (1 mil) is carefully added to a solution of solasonine or solasodine in hot alcohol (1 mil) a characteristic, intense, greenish-yellow fluorescence is produced, a reaction which is not given by solanine or solanidine. They have also found that intense colours are formed when solasonine or solasodine is mixed with resorcinol, or one of a variety of aldehydes, and boiled with concentrated hydrochloric acid. Colours are also produced with this test by cholesterol, digitonin, jacobine carbazole, pyrrole, or nicotine, the most intense colours being formed with p-hydroxybenzaldehyde or anisaldehyde. [Pg.668]

In 1878, Hofmann reported that treatment of D-l-bromo-2-propylpiperidine (3) with hot sulfuric acid gave rise to a tertiary amine 4, D-octahydroindolizine. In the ensuing decade, Loffler and Freytag extended the reaction to simple secondary amines and found it to be a general way to synthesize pyrrolidines as exemplified by transformation of N-bromo-A-methyl-2-butylaminylpyridine 5 to nicotine (6). The Hofmann-Loffler-Freytag reaction is sometimes referred to as Loffler s method, Hofmann-Loffler reaction, Loffler-Hofmann reaction, as well as Loffler-Freytag reaction. [Pg.89]

Free nicotinic acid can exist in neutral (21) and in zwitterion forms (22). On reaction with acid either form is converted into the same... [Pg.256]

The reaction products are 2,4-dimethyl-3-acetylpyridine (11) and ethyl ester of 2,4-dimethyl-3-nicotinic acid (12). [Pg.163]

Reaction of -picoline over degassed Raney nickel was found to give 5,5 -dimethyl-2,2 -bipyridine (5), the structure of which was established by its synthesis from 2-bromo-5-methylpyridine. Oxidation of this dimethyl-2,2 -bipyridine, and similar oxidation of the diethyl-2,2 -bipyridine derived from 3-ethylpyridinc, gave the corresponding dicarboxylic acid and the same acid was produced by the action of degassed Raney nickel on sodium nicotinate (in water) or on ethyl nicotinate. These transformations established the 5,5 -substitution pattern for three 2,2 -bipyridines derived from 3-substituted pyridines but such evidence is not available for the biaryls... [Pg.184]

Relatively few pyridines with substituents other than alkyl groups have so far been examined, and with some of these the reaction has been carried out only in the presence of added solvent. A comparison of the reactivities of these pyridines is therefore difficult. It has, however, been established that the presence of benzoyl groups in the 3- and 4-positions causes a very marked drop in the yields of the corresponding 2,2 -bipyridines. The 3- and 4-benzylpyridines were found to be more reactive but even in the absence of solvent, and in vacuo, 4-benzylpyridine gave only about one-third of the yield of the 2,2 -bipyridine compared with pyridine itself. Ethyl nicotinate in the absence of solvent and under vacuum -- gave a similar yield of biaryl but 4-phenylpyridine was found to be less reactive. [Pg.186]

The Hofmann-Loeffler-Freytag reaction has been described with A-chloro-as well as A-bromoamines—the former however usually give better yields. A-chlorinated primary amines react well in the presence of Fe-(II) ions. Just like the Barton reaction, the Hofmann-Loeffler-Freytag reaction has been applied mainly in steroid chemistry. An interesting example from alkaloid chemistry is the synthesis of nicotine 12 by Loeffler ... [Pg.27]

Condensation of ethyl acetoacetate with phenyl hydrazine gives the pyrazolone, 58. Methylation by means of methyl iodide affords the prototype of this series, antipyrine (59). Reaction of that compound with nitrous acid gives the product of substitution at the only available position, the nitroso derivative (60) reduction affords another antiinflammatory agent, aminopyrine (61). Reductive alkylation of 61 with acetone in the presence of hydrogen and platinum gives isopyrine (62). Acylation of 61 with the acid chloride from nicotinic acid affords nifenazone (63). Acylation of 61 with 2-chloropropionyl chloride gives the amide, 64 displacement of the halogen with dimethylamine leads to aminopropylon (65). ... [Pg.234]

Conversion of the carboxylic acid to the diethyl amide interestingly leads to an agent that exhibits the properties of a respiratory stimulant. One synthesis of this agent starts with the preparation of the mixed anhydride of nicotinic and benzene-sulfonic acid (4). An exchange reaction between the anhydride and diethyl benzenesulfonamide affords nikethemide (5). ... [Pg.253]

Preparation of the first of these antiinflammatory prodrugs starts with the displacement of halogen on bromophthal ide 2 by the anion of the nicotinic acid derivative 1. Reaction of the intermediate 3 with aniline 4 leads to formation of talniflumate (5). ... [Pg.146]


See other pages where Reaction nicotinic is mentioned: [Pg.48]    [Pg.210]    [Pg.201]    [Pg.36]    [Pg.72]    [Pg.48]    [Pg.210]    [Pg.201]    [Pg.36]    [Pg.72]    [Pg.274]    [Pg.849]    [Pg.26]    [Pg.337]    [Pg.51]    [Pg.244]    [Pg.27]    [Pg.710]    [Pg.710]    [Pg.7]    [Pg.38]    [Pg.40]    [Pg.751]    [Pg.238]    [Pg.259]    [Pg.297]    [Pg.299]    [Pg.104]    [Pg.197]    [Pg.197]    [Pg.128]    [Pg.35]    [Pg.148]   
See also in sourсe #XX -- [ Pg.132 , Pg.148 , Pg.327 ]




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Ethyl 2,4-dimethyl-3-nicotinate Ethylene, Diels-Alder reaction with oxazoles

Nicotine adenine dinucleotide, reaction with

Nicotinic acid, reaction with

Nicotinic acids, methyl-, reaction with

Nicotinics, adverse reaction

Survey of Reactions in Nicotinic Acid and Its Derivatives

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