Propionamide, hydrolysis

Photolytic. Photoproducts reported from the sunlight irradiation of propanil (200 mg/L) in distilled water were 3 -hydroxy-4 -chloropropionanilide, 3 -chloro-4 -hydroxypropionanilide, 3, 4 -di-hydroxypropionanilide, 3 -chloropropionanilide, 4 -chloropropionanilide, propionanilide, 3,4-di-chloroaniline, 3-chloroaniline, propionic acid, propionamide, 3,3, 4,4 -tetrachloroazobenzene, and a dark polymeric humic substance. These products formed by the reductive dechlorination, replacement of chlorine substituents by hydroxyl groups, formation of propionamide, hydrolysis... 

Then it was alkylated with iodide (168) in the presence of HMPA. Finally the reaction was quenched to produce (169) in 46% yield with 96.6% diastereomeric purity. The amide (169) was hydrolyzed to produce (R)-(170) with 93% e.e. In the same manner, by alkylating (R)-prolinol propionamide with (168), the amide (169 ) was obtained. Acid hydrolysis of (169 ) produced (S)-( 170) with 92% e.e. 

The presence of the propionamide fragment in the stmcture of the anti-inflammatory agent broperamole (125-1) is reminiscent of the heterocycle-based NSAID propionic acids. The activity of this agent may trace back to the acid that would result on hydrolysis of the amide. Tetrazoles are virtually always prepared by reaction of a nitrile with hydrazoic acid or, more commonly, sodium azide in the presence of acid in a reaction very analogous to a 1,3-dipolar cycloaddition. A more recent (and safer) version of the reaction noted later (see losartan, 77-4) uses tributyltin azide. In the case at hand, reaction of the anion of mefa-bromobenzonitrile (125-1) with sodium azide and an acid affords the tetrazole (125-2). Condensation of the anion from that intermediate with ethyl acrylate leads to the product from Michael addition saponiflcation gives the corresponding carboxylic acid (125-3). This is then converted to the acid chloride reaction with piperidine affords broperamole (125-4) [136]. 

Comparison of the activation parameters for carbonyl-oxygen exchange and for hydrolysis shows that, for the formamide, the rate of exchange is only slightly lower than that of hydrolysis, whereas in the case of acetamide and propionamide, the exchange occurs at a significantly lower rate. 

Lithium enolates of propionamides of chiral amines undergo stereoselective 1,4-addition reactions to a,P-unsaturaled esters. The highest selectivities are obtained with C2-symmetric amides derived from 1.65 (R = CH OCH QMie) bearing a substituent that is capable of metal chelation (Figure 7.61). After hydrolysis, diacid 7.95 is obtained with a good selectivity [161]. Some nonracemic natural... 

Chlorosulphonation of 4 -chloro-o-acetotoluidine yields the eorresponding sulphonyl chloride derivative whieh on amination forms the sulphonamide derivative. Oxidation of the methyl moiety gives the respeetive anthranilamide derivative whieh on hydrolysis eliminates the acetyl group to yield the substituted anthranilic acid. Fusion of this amino acid with propionamide first gives rise to an intermediate by the loss of a mole of water and ultimately helps in the closure of the ring to generate the quinazoline ring system. Catalytic reduction of this finally produces the official compound. 

The rates of hydrolysis and carbonyl-oxygen exchange carried out at 27°C with potassium hydroxide (1.5 N) on labeled N-benzyl-N-methyl derivatives of formamide ( 1 ). acetamide (22), and propionamide ( ) have been reported (14). 

The herbicides N-(3,4-dichloro-phenyl) propionamide (Propanil), N-(3,4-dichlorophenyl) methylacryl amide (Diciyl), and N-(3,4-dichloro-phenyl)-2-methylpentanamide (Karsil) were transformed into 3,4-dichloroaniline [222-225]. The a[Pg.22]

By introducing appropriate linkers, conjugation at the ( -propionamide site of the corrin ring may also result in TC-binding Bj2 derivatives. This approach requires controlled hydrolysis of the propionamide chains and isolation of the b-monocarboxylic acid prior to conjugation. For Tc-PAMA derivatives, a long spacer of >5 CH2 ensured binding to TC, while derivatives with shorter spacers were still able to bind HC and IF but not TC (Allis et al. 2010, Waibel et al. 2008). 

The combination of this radical with the Bi2r species generates a new alkyl cobalamin with the substrate as ligand. We have thus accomplished a transalkylation of the cobalt atom. How does the Co—C bond become activated toward homolytic cleavage It is believed that the presence and proper orientation of the propionamide side chains on the corrin ring are responsible for the ease of the enzymatic system, possibly by some distortion of the corrin (269). Support for this hypothesis comes from the fact that hydrolysis of a side chain to the corresponding acid results in an inactive coenzyme Bi2 molecule. It is not known why nature proceeds by homolytic fission, a unique situation in coenzyme chemistry ... 

Frankenberger and Tabatabai have described an assay for soil amida.ses, which catalyse the hydrolysis of aliphatic amides to carboxylic acids and ammonia. Their assay requires toluene-treated soils to be incubated at 37°C with 0.05M substrate (formamide, acetamide, propionamide) for either 2 or 24h. The suspensions were buffered at pH 8.5 the choice of buffer influenced the amounts of NH4 released, which formed the basis for estimating activities. The pH optimum for hydrolysis of all substrates was about pH 8.5 the optimum temperature was about 65°C. Reaction rates in the presence of toluene were linear both with time and with the amounts of soil when substrate concentrations were 0.05M. At this concentration, and above, the reactions exhibited zero-order kinetics for the recommended assay periods. 

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