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Amino compounds protection

Three selective methods to remove protective groups are receiving much attention assisted, electrolytic, and photolytic removal. Four examples illustrate assisted removal of a protective group. A stable allyl group can be converted to a labile vinyl ether group (eq. 4) a /3-haloethoxy (eq. 5) or a /3-silylethoxy (eq. 6) derivative is cleaved by attack at the /3-substituent and a stable o-nitro-phenyl derivative can be reduced to the o-amino compound, which undergoes cleavage by nucleophilic displacement (eq. 7) ° ... [Pg.2]

The mesoionic azolides are reported to be relatively stable toward hydrolytic decomposition, but more reactive against amines than the corresponding imidazo-lides.[194] -Protection of the amino compounds (for example by the Boc group) takes place smoothly at room temperature in about one to five hours and with high yield. The amino acids are introduced as sodium salts in aqueous acetone. [Pg.140]

Many different approaches have been developed for peptide synthesis, and it is not the intention to cover more than the basic principles here, with a suitable example. The philosophy to convert two amino acids into a dipeptide is to transform each difunctional amino acid into a monofunctional compound, one of which has the amino group protected, whilst the other has the carboxyl group protected. This allows... [Pg.540]

Protection of amino compounds by the 2,4-bis(methylthio)phenoxycarbonyl residue [266] converts them into acid stable entities. Removal of the protecting group can be achieved through oxidation at sulfur such that the resulting bissulfone provides conjoint pathways for ready fragmentation. [Pg.148]

The commonly encountered compounds in this class are the formyl, acetyl and benzoyl derivatives. The formation of the N-formyl compound is readily accomplished by heating the amino compound with formic acid in the presence of acetic anhydride.223 Alternatively, formic acid in the presence of dicyclohexl-carbodiimide (DCC) in pyridine solution is a suitable method for the protection of amino acid esters.224... [Pg.784]

V-acetylmethionine in quantities equal to LZM. Inactivation of LZM also may be restricted upon addition of /V-acetylcystine or /V-acetyltryptophan. The /V-acetylo-tryptophan competes with LZM for the oxidizing agent. Amino compounds binding hypochlorite to relatively stable chloramines, such as leucine, lysine, and taurine, do not protect LZM from MPO-mediated reaction. Oxidation of tryptophan residues in lysozyme molecules treated with HOC1 occurs along with a decrease of lysozyme spectral properties at 280 nm. [Pg.198]

Transformation of a-Azido Compounds into Boc-Protected Amino Compound General Procedureti i... [Pg.149]

Diallyl dicarbonate was used for the allyloxycarbonyl protection of amino compounds including amino acids, amino sugars and nucleosides. Except for the reaction with amino acids, the reagent does not require an additional base, and the only by-products, allyl alcohol and carbon dioxide are both volatile. For example, N-allyloxycarbonyl glucosamine was obtained analytically pure by simple evaporation of the reaction mixture. [Pg.26]

However, the reagent is not stable enough to be shipped safely because it decomposes more or less rapidly into isobutene, carbon dioxide and HF, thus developing autogenous pressure in containers. This has led SNPE and its subsidiary ISOCHEM to manufacture and react BOC-F on site, thus offering low cost protected amino compounds. [Pg.38]

Over half of the remaining market for products used in the processing of rubber is made up of antioxidants, antiozonants and stabilizers, either amino compounds or phenols. Aniline is used to manufacture vulcanization accelerators, antioxidants and antidegradants. Of the latter, several are A-substituted derivatives of p-phenylenediamine and octyl dipheny-lamine. Diphenylamines terminate free-radical reactions by donating the amino hydrogen, and are used to protect a wide range of polymers and elastomers. Many synthetic rubbers incorporate alkylated diphenylamine antioxidants. Other antioxidants include aryl amine resinous products from, e.g. condensation of aniline and acetone in the presence of... [Pg.768]


See other pages where Amino compounds protection is mentioned: [Pg.148]    [Pg.148]    [Pg.148]    [Pg.148]    [Pg.338]    [Pg.138]    [Pg.140]    [Pg.25]    [Pg.30]    [Pg.44]    [Pg.64]    [Pg.130]    [Pg.285]    [Pg.224]    [Pg.165]    [Pg.144]    [Pg.151]    [Pg.132]    [Pg.26]    [Pg.269]    [Pg.44]    [Pg.225]    [Pg.170]    [Pg.353]    [Pg.228]    [Pg.80]    [Pg.228]    [Pg.170]    [Pg.83]    [Pg.123]    [Pg.344]    [Pg.601]    [Pg.279]    [Pg.638]    [Pg.677]    [Pg.443]    [Pg.27]    [Pg.135]    [Pg.154]    [Pg.157]   
See also in sourсe #XX -- [ Pg.594 , Pg.595 ]

See also in sourсe #XX -- [ Pg.594 , Pg.595 ]




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Amino compounds

Protecting amino

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