Amides arylamide

These amides (45), which are of the Naphthol AS type, are important coupling components that are appHed to fiber, eg, cotton (qv). They then react with a dia2o component on the fiber to produce insoluble a2o dyes of high washfastness and lightfastness. A wide range of arylamides of... 

This zinc-dependent enzyme [EC 3.4.11.1], also referred to as cytosol aminopeptidase, leucyl aminopeptidase, and peptidase S, catalyzes the hydrolysis of a terminal peptide bond such that there is a release of an N-terminal amino acid, Xaa-Xbb-, in which Xaa is preferably a leucyl residue, but may be other aminoacyl residues including prolyl (although not arginyl or lysyl). Xbb may be prolyl. In addition, amino acid amides and methyl esters are also readily hydrolyzed, but the rates with arylamides are exceedingly slow. The enzyme is activated by heavy metal ions. 

The regioseledivity of the last reaction in Scheme 5.13 is not only because of the greater acidity of the methylene group, but also because some secondary and tertiary amides (e.g. /3-arylamides, /3-vinylamides, or /3-(phenylthio)amides, or borane complexes of /3-phosphino propionamides [132, 133]) are deprotonated at the /3 position under kinetic control to yield chelate-stabilized carbanions [58, 134], Illustrative examples of such remarkable metalations are shown in Scheme 5.14. 

O-Aeyl- -S,S-dialkylester XII/2, 821 -(alkoxycarbonylimid)-triphenylester E2, 825 -amid-bis-[alkylaminocarbonyl-methylesterj E2, 772 -aniid-diethylester E2, 773 -S-(2-ainino-cthylester)-S,S-diester E2, 752 -arylamid-diester E2, 771... 

Lyotropic liquid crystalline properties were observed for poly (arylamide) monodendrons derived from 1,3,5-substituted amino acid chloride hydrochlorides according to Kim [168]. These systems aggregate readily to form high molecular weight species in the absence of complexing ions. Amide solvents containing more than 40 wt.% of the dendrons exhibit nematic phase liquid crystalline texture under a polarizing microscope, whereas, 60 wt.% solutions produce a hard gel under static conditions. 

In more recent work involving a series of alkyl, aralkyl and arylamides of MTX and AMT [316], MeAPA was condensed with a-benzyl L-glutamic acid y-3,4-methylenedioxyanilide by the diethyl phosphorocyanidate coupling procedure to obtain the ester amide (VIII. 195). The benzyl ester group in (VIII.195) was then removed with NaOH to form (VIII.196) in 64% overall yield. Further reaction of (VIII.196) with boron tris(trifluoroacetate) in tri-fluoroacetic acid at 0 °C for 15 min afforded MTX y-(3,4-dihydroxyanilide) ((VIII.197) 79% yield). AMT y-amides (VIII.198)-(VIII.205) were prepared via the blocked intermediates (VIII.206)-(VIII.213), which were generated from FmAPA by the modified mixed anhydride route (four activation cycles ... 

Buchwald s research indicated that vicinal diamines, such as ethylenediamine (EDA, L12), raotra saryl halides (Table 9.6, entry 1) [21, 31], This catalytic system allowed a wide range of amides (including lactams, open chain alkylamides and arylamides) and carbamates to be coupled with aryl halides. The hindered amides also gave good results. The reaction occurred at about 80-110 °C. Remarkably, DMCyDA (LIO) could even promote the amidation of deactivated aryl chlorides at a Uttle higher reaction temperature (110-130°C). 

Trimethylsilyl derivatives of amides seem to be more appropriate for GC analysis.However, the molecules of amides contain two nucleophilic centers (N and (9) and, depending on their chemical origin, they can form V-TMS or G-TMS derivatives. The latter prevails in the case of arylamides, like A -aroyl amides [e.g., A -benzoyl glycine (hippuric acid)], owing to the formation of conjugate systems (usually both mono- and fofr-TMS derivatives are registered on the chromatograms) (Fig. 9). 

A unique example of direct olefination of a cyclopropane was also disclosed by the Yu lab [21]. An electron-deficient arylamide was employed as directing group, as the previously employed oxazoline or hydroxamic acid was unreactive in the alkenylation. The proposed mechanism for the reaction involves an amide-directed C-H insertion of the Pd(II) catalyst into the cyclopropane methylene C-H bond of 9, followed by olefin carbopalladation and p-hydride elimination to provide intermediate 10 (Scheme 3a). Pd(0) is re-oxidized back to Pd(II) by Ag(I)/Cu(II), and a tandem 1,4-addition between the amide moiety of 10 and the acrylate provides the corresponding y-lactam 11 as the sole isolated product, fii the presence of an... 

Arylmethylamines can be oxidized to the corresponding arylamides by formation of a Schiff base with 2,6-di-t-butylbenzoquinone and base-catalysed oxygenation. Allenic alcohols are oxidized to allenic amides by nickel peroxide at -20 °C in ethereal ammonia. N-Alkyl-amides can be prepared from aldehydes in a four-step procedure consisting of imine formation and subsequent reactions with N-chlorosuccinimide, potassium cyanide, and finally alcoholic HCl. ... 

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