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Amides Chromophoric groups

Listowsky and coworkers showed that the c.d. of this sugar derivative is due entirely to lactic acid, and confirmed that this chromophore is in the D configuration for muramic acid. N-Acetylmuramic acid, in which the amino group is replaced by an amido group at C-2, has a c.d. spectrum that is roughly a linear combination of the lactic acid in muramic acid and the amide in 2-acetamido-2-deoxy-D-glucose. This indicates that the amide chromophore and the lactic acid chromophore in N-acetylmuramic acid behave independently. [Pg.113]

Chromophoric derivatives for the optically transparent amino group, such as dimedone derivatives 103-106, were prepared for assigning the absolute configuration of primary and secondary amines. The vinylogous planar amide chromophore (280-290 nm ji — n ... [Pg.222]

If the side chains have strongly chromophoric groups near the backbone, such as in polymers of aromatic amino acids like poly(L-phenylalanine), poly(L-tyrosine), and poly(L-tryptophan), the CD spectrum is strongly dependent on the side chains and is totally different from the standard spectra of polypeptides lacking chromophoric groups in the side chains. This is due to the interactions between amide and aro-... [Pg.403]

In order to define the structure of a peptide fully, it is necessary not only to ascertain the configuration around the asymmetric a-carbon atoms, but also to specify the conformation or spatial (chiral) relationships of the various groups comprising the whole molecule. Apart from glycine, the amino acids constituting natural peptide molecules are all optically active and have one or several centers of asymmetry. As a consequence, the amide chromophore (71) is optically active in this dissymmetric surrounding. The... [Pg.151]

Characteristic IR absorption bands of PAI-l(Fig.4), PAI-2 (Fig. 5.) and PAI-3 (Fig. 6) were observed near 1785 cm , 1715 cm and 725 cm"l due to imide groups and near 1630 cm" and 1530 cm" due to amide groups. Because of the complex structure of the polymer, characteristic IR bands observed were not so sharp due to overlapping of different bands of various chromophore groups present in the rosin polymer molecule. [Pg.136]

The rotatory properties of molecules containing two or more amide groups have been actively investigated [13—15], and it has been demonstrated that both intensity and sign of the resultant rotatory strength are conformation dependent, i.e., the CD spectral patterns are subject to variation with the relative spatial orientations of the amide chromophores in the molecule [13-15]. [Pg.211]

Amino-4,6-dimethyl-3-oxo-3//-phenoxazine-l,9-dicarboxylic acid also named actinocin is the chromophor of the red antineoplastic chromopeptide aetinomyein D (formula A). Two cyclopenta-peptide lactone rings (amino acids L-threonine, D-valine, L-proline, sarcosine, and 7V-methyl-L-valine) are attached to the carboxy carbons of actinocin by two amide bonds involving the amino groups of threonine. [Pg.246]

V-Acetylneuraminic acid is a common group in glycoproteins, and it contains both the amide and carboxyl chromophores. As shown in formula 11, this nine-carbon sugar derivative has an equatorial amido group on C-5 and both a hydroxyl group and a carboxyl group on the anomeric carbon atom. [Pg.111]


See other pages where Amides Chromophoric groups is mentioned: [Pg.277]    [Pg.322]    [Pg.277]    [Pg.168]    [Pg.172]    [Pg.761]    [Pg.16]    [Pg.277]    [Pg.654]    [Pg.277]    [Pg.168]    [Pg.172]    [Pg.654]    [Pg.728]    [Pg.354]    [Pg.251]    [Pg.282]    [Pg.6317]    [Pg.275]    [Pg.279]    [Pg.288]    [Pg.112]    [Pg.277]    [Pg.326]    [Pg.21]    [Pg.2125]    [Pg.70]    [Pg.267]    [Pg.1044]    [Pg.285]    [Pg.147]    [Pg.210]    [Pg.133]    [Pg.229]    [Pg.535]    [Pg.146]    [Pg.390]    [Pg.277]    [Pg.286]    [Pg.176]    [Pg.78]    [Pg.117]    [Pg.317]   
See also in sourсe #XX -- [ Pg.137 ]

See also in sourсe #XX -- [ Pg.137 ]




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Amide groups

Chromophores amide

Chromophoric group

Chromophorous groups

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