2-Amino-2-carboxy- -Hydrochlorid

Trichloromethyl chloroformate has proven effective in the preparation of N-carboxy-a-amino acid anhydrides from amino acids, and various compounds having isocyanate, acid chloride, and chloroformate groups.For example, trichloromethyl chloroformate may be used instead of phosgene in the preparation of 2-tert-butoxycarbonyloxyimino-2-phenylacetonitrile. The use of this reagent is illustrated here by the synthesis of 3-isocyanato-propanoyl chloride from 3-aminopropanoic acid hydrochloride. 

Knobler Y, Bittner S, Frankel M (1964) Reaction of N-carboxy-alpha-amino-acid anhydrides with hydrochlorides of hydroxylamine O-alkylhydroxylamines + amines syntheses of amino-hydroxamic acids amido-oxy-peptides + alpha-amino-acid amides. J Chem Soc 3941... 

An amino acid (0.4 mol based on carboxy group), HF (50 g, 2.5 mol) and SF4 (100 g, 0.93 mol) were reacted in a 400-mL stainless steel tube at 120 C for 8 h, The products were poured into a polyethylene dish and heated on a steam bath to expel HF, then made strongly alkaline with aq NaOH and steam distilled. The higher amines sparingly soluble in water, were extracted with Et,0. which was dried and distilled. For the lower, water-soluble amines, the steam distillate was acidified with HC1 and evaporated to dryness to give the amine hydrochloride. The free amine was liberated from the hydrochloride with 40 % "aq KOH. 

The 8-oxo-7-phenylacetylamino-5-thia-l-aza-bicyclo[4.2.0]oct-l-ene-2-carboxylic acid benzhydryl ester is reacted with phosphorus pentachloride/pyridine reagent in methylene dichloride, and the reaction mixture is thereafter cooled to -35°C and treated with methanol to produce hydrochloride of 7-amino-8-oxo-5-thia-l-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester. This hydrochloride is reacted with 4-(3-aminothiophen-2-yl)-5-oxohex-3-enoic acid 3-methylbut-2-enyl ester. Then 7-[2-(2-benzoylamino-thiazol-5-yl)(3-tert-butyl-4,4-dimethylpent-2-enoxycarbonyl)-pent-2-enoylamino]-8-oxo-5-thia-l-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid synthesized is reacted with aluminum chloride in anisole and diluted hydrochloric acid and then with dimethylmalonate to give 5-thia-l-azabicyclo(4.2.0)oct-2-ene-2-carboxylic acid, 7-(((2Z)-2-(2-amino-4-thiazolyl)-4-carboxy-l-oxo-2-butenyl)amino)-8-oxo-, (6R,7R)- (Ceftibuten). 

Synthesis and Polymerization of Leuchs Anhydrides. The N-carboxy-a-amino acid anhydrides, referred to as Leuchs anhydrides or as NCAs, are synthesized either from N-alkoxycarbonyl derivatives of a-amino acids or from free amino acids. Cyclization of the amino acid derivative by SOCl2 or similar reagents was described first by Leuchs in 1906, but direct synthesis involves treating the a-amino acid or its hydrochloride with phosgene as shown in Figure 4. This method, commonly termed the Fuchs-Farthing method, is the one that is used most frequently since the N-carboxyanhydride may be freed easily from the carbamyl chloride, isocyanate derivative, and hydrogen chloride by crystallization. 

Y)-3-[[(LS )-1 -Carboxy-3-phenylpropyl]amino]-2,3,4,5-tctrahydro-2-oxo-1 H- 1-benzazepin-l -acetic acid-3-ethyl ester, hydrochloride. 

The colonial sea anemone Anthopleura elegantissima responds with characteristic contraction to a pheromone released by wounded conspecifics. This alarm response is highly characteristic, includes rapid bending and shortening of the tentacles and depression of the oral disk. In 1975, by extensive ion exchange column chromatography, (3-carboxy-2,3-dihydroxy-A(A(Af-trimethyl)-l-propanaminium chloride (50) was isolated as a pure crystalline substance.116 It showed alarm pheromone activity with a median concentration of 0.35 nmol 1 1 and was named anthopleurine. Comparison of spectral data between natural and synthetic compounds revealed that anthopleurine had a structure of 4-amino-4-deoxy-L-threonic acid betaine hydrochloride.117... 

Glutarsaure 2-Amino- -5-(1 -carboxy-2-mercapto-ethyl-amid) (Hydrochlorid) XV/1, 776... 

Di(j8-carboxy-j8-aminoethyl)-3-amino-4-hydroxyphenylthio-arsinite is obtained by the int(a ac tion of 3-annno-4-hydroxyphenyl-arsinic acid and cysteine hydrochloride it crystallises in line, matted needles,... 

An aq. soln. of 6-amino-7-octanone-l-carboxylic acid hydrochloride mixed with NH4-thiocyanate, evaporated to dryness on a steam bath during K hrs., the product evaporated twice with water, HC1 added, and allowed to stand 24 hrs. —l-methyl-5- (fo-carboxy-n-pentyl)-imidazole-2-thione. Y 69%. (F. e. with lower yields s. G. Swain, Soc. 1948, 1552.)... 

Pyrrolidinium, [6R-(6a, 7P(Z)]]-l-[[7-(2-amino-4-thiazolyl) (methoxy-imino) acetyl] amino-2-carboxy-8-oxo-5-thia-l-azabicyclo [4,2,0] oct-2-ene-3yl]-methyl]- -methyl-, hydroxide, inner salt hydrochloride ... 

Carboxy- and amino-functionaUzed polystyrene nanoparticles have been synthesized by the miniemulsion process using styrene and the functional monomers acrylic acid (AA) or 2-aminoethyl methacrylate hydrochloride (AEMH) as functional comonomers [30,31]. By changing the amount of the comonomer, different surface densities of the charged groups could be realized. Since a fluorescent dye was incorporated inside the nanoparticles, the uptake behavior of different cell Unes could be determined as a function of the surface functionalization [30,31]. It was found that, in general, the uptake of the nanoparticles into the cells increases with increasing functionality on the particle s surface. For HeLa cells, for example, the internalized particle amount was up to sixfold better for carboxy-functionaUzed polystyrene (PS) nanoparticles than for non-functionalized PS particles. For amino functionalized PS nanoparticles, an up to 50-fold enhanced uptake could be detected. In order to investigate the actual uptake pathway into HeLa cells, positively... 

A further step towards efficient biomedical application of PU/PUR nanocapsules was shown by the work of Paiphansiri et al. [190]. Carboxy- and amino-functionalization of the nanocapsules surface can be introduced and tailored by an in situ carboxymethylation reaction or by physical adsorption of a cationic polyelectrolyte, i.e., poly(aminoethyl methacrylate hydrochloride) or poly(ethylene imine) (see Fig. 21). Encapsulation of an aqueous solution of suforhodamine adds a fluorescent label for fluorescence microscopic detection (see Fig. 21). Whereas the carboxy-functionalized nanocapsules do not lead to a good uptake into cells, the increased uptake of amino-functionalized fluorescent nanocapsules by HeLa cells clearly demonstrates the potential of the functionalized nanocapsules to be successfully exploited as biocarriers. These results are in good agreement with the data obtained from experiments with PS particles [192]. 

A suspension of 3-amino-4-carboxy-2-thiophenevaleric acid hydrochloride in xylene refluxed 2 days with removal of the resulting water by a Dean-Stark trap 3-amino-4-carboxy-2-thiophenevaleric acid f-lactam (startg. m. f. 324). Y 85%. P. N. Confalone, G. Pizzolato, and M. R. Uskokovic, J. Org. Chem. 42, 135 (1977). 

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