Propionic acid, degradation product

Degradatiou. Heating of succinic acid or anhydride yields y-ketopimehc ddactone, cyclohexane-1,4-dione, and a mixture of decomposition products that include acetic acid, propionic acid, acryUc acid, acetaldeide, acrolein, oxaUc acid, cyclopentanone, and furane. In argon atmosphere, thermal degradation of succinic anhydride takes place at 340°C (123). Electrolysis of succinic acid produces ethylene and acetylene. 

In order to obtain information regarding the composition of these degradation products, aqueous extracts of the lead soaps of the linseed oil fatty acids were analysed, mainly by chromatography. The extracts contained formic acid 46%, azelaic acid 9% and pelargonic acid and its derivatives 27%, the remaining 18% consisting of a mixture of acetic, propionic, butyric, suberic, pimelic and adipic acids. It was shown that whereas the salts of formic acid were corrosive, those of azelaic and pelargonic acid were very efficient inhibitors. 

Tocopheryl)propionic acid (50) is one of the rare examples that the o-QM 3 is involved in a direct synthesis rather than as a nonintentionally used intermediate or byproduct. ZnCl2-catalyzed, inverse hetero-Diels-Alder reaction between ortho-qui-none methide 3 and an excess of <2-methyl-C,<9-bis-(trimethylsilyl)ketene acetal provided the acid in fair yields (Fig. 6.37).67 The o-QM 3 was prepared in situ by thermal degradation of 5a-bromo-a-tocopherol (46). The primary cyclization product, an ortho-ester derivative, was not isolated, but immediately hydrolyzed to methyl 3-(5-tocopheryl)-2-trimethylsilyl-propionate, subsequently desilylated, and finally hydrolyzed into 50. 

Soil. Propanil degrades in soil forming 3,4-dichloroaniline (Bartha, 1968, 1971 Bartha and Pramer, 1970 Chisaka and Kearney, 1970 Duke et al., 1991) which degrades via microbial peroxidases to 3,3, 4,4 -tetrachlorazobenzene (Bartha and Pramer, 1967 Bartha, 1968 Chisaka and Kearney, 1970), 3,3, 4,4 -tetrachloroazooxybenzene (Bartha and Pramer, 1970), 4 (3,4-dichloroanilo)-3,3, 4,4 -tetrachloroazobenzene (Linke and Bartha, 1970), and l,3-bis(3,4-dichloro-phenyl)triazine (Plimmer et al., 1970), propionic acid, carbon dioxide, and unidentified products (Chisaka and Kearney, 1970). Evidence suggests that 3,3, 4,4 -tetrachloroazobenzene reacted with... 

After 15 days of degradation only low amounts of degradation products have evolved, the amount being lower than the detection limit of the GC system. After 17 weeks, however, 2-butanol, propionic acid, 1-pentanol, but3nic acid, valeric acid and caproic acid were detected in pH 6 water fraction. After another 20 weeks several alkanes could also be detected n-octane, n-nonane, n-decane, n-dodecane, n-tridecane and n-tetradecane (13). 

This pathway is also important for ruminant animals, which are dependent on symbiotic microorganisms to break down their food. The microorganisms produce large amounts of propionic acid as a degradation product, which the host can channel into the metabolism in the way described. 

Soil/Environment. c. 5800. In moist soils, rapid degradation of fluazifop-P-butyl occurs, DT50 <24 hr. The major degradation product is fluazifop-P, which is hydrolyzed to 5-trifluoromethylpyrid-2-one, and 2-(4-hydroxyphenoxy)propionic acid, both of which are further degraded ultimately to C02... 

An interesting use was made of solubility analysis in a stability study of propoxyphene hydrochloride13. In this study, propoxyphene hydrochloride was stored at 80°C, 105°C, and 130°C. Both the solubility analysis and the alternate IR assay showed the thermal stability of propoxyphene hydrochloride. Gas chromatography can be used to measure the slow hydrolysis of propoxyphene hydrochloride in aqueous solutions. The hydrolytic products are propionic acid and (+)-a-4-(Dimethylamino)-3-methy1-1,2-diphenyl-2-butanol. With suitable gas chromatographic conditions either product can be quantitated. A chloroform extraction of an alkaline solution of propoxyphene hydrochloride (where degradation has occurred) can be assayed using the previously described IR method. 

Further breakdown to mono-pyrrolic oxygenation products as further remains of Chls have also been considered (3, 102). These studies received further support from recent work by Shioi and coworkers, who obtained evidence for the presence of hematinic acid (4-methyl-2,5-dioxo-2,5-dihydropynole-3-propionic acid), ethyl-methyl-maleimide and a putative bicyclic degradation product of the ring-C-E section of Pheo a (103). 

Meroquinene (1) is a key synthetic precursor of a number of medicinally important alkaloids such as quinine (2) andcinchonamine (3). Meroquinene andhomomeroquinene, (Sli l-vinyl-ldSl-piperidine propionic acid, are also degradation products of cinchonine. " ... 

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