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Heterocycle side chains

Burkoth, T. S., Faearman, A.T., Char-YCH, D. H., Connolly, M.D., and Zuckermann, R.N. Incorporation of unprotected heterocyclic side chains into peptoid oligomers via solid-phase submonomer synthesis. J. Am. Chem. Soc. 2003 125, 8841-8845. [Pg.28]

Amino Acids with Heterocyclic Side Chains 32... [Pg.5]

Table 7 Nonprotein amino acids containing heterocyclic side chains... Table 7 Nonprotein amino acids containing heterocyclic side chains...
Tryptophan possesses a complex heterocyclic side chain known as indole. It is the metabolic precnrsor to serotonin (5-hydroxytryptamine 5-HT), an important nenrotransmitter. [Pg.123]

Histidine is characterized by a heterocyclic side chain known as imidazole. The imidazole group will bear a positive charge under physiological conditions. Histidine is the metabolic precursor to histamine, a potent inflammatory molecule. Antihistamines work by antagonizing the action of histamine. [Pg.126]

Interestingly, the heterocyclic side-chain of histidine is partially ionized at pH 7.0. This follows from... [Pg.152]

The imidazole side-chain of histidine has a value of 6.0, making it a weaker base than the unsubstituted imidazole. This reflects the electron-withdrawing inductive effect of the amino group, or, more correctly the ammonium ion, since amino acids at pH values around neutrality exist as doubly charged zwitterionic forms (see Box 4.7). Using the Henderson-Hasselbalch equation, this translates to approximately 9% ionization of the heterocyclic side-chain of histidine at pH 7 (see Box 4.7). In proteins, plCa values for histidine side-chains are estimated to be in range 6-7, so that the level of ionization will, therefore, be somewhere between 9 and 50%, depending upon the protein. [Pg.434]

Attaching a heterocyclic side chain at the 0-2" of paromomycin has also been reported (Figure 4.18). These compounds have similar activity as compared to paromomycin (Table 4.19). [Pg.176]

Clarke, A. J. McNamara, S. Meth-Cohn, O. Novel aspects of the metalation of heterocycles. Side-chain metalation of thiophene and ring metalation of six-membered nitrogen heterocycles. Tetrahedron Lett. 1974, 2373-2376. [Pg.221]

Another example of industrially viable biooxidation of N-heterocycles side chain oxidation is the oxidation of 2-methylquinoxaline to 2-quinoxalinecar-boxylic acid by Pfizer [134]. [Pg.168]

D2O. Spectral characteristics of sulfacetamide and sulfonamides with heterocyclic side chains are reported (65). [Pg.492]

End, N., Bold, G., Caravatti, G., Wartmann, M., Altmann, K.-H., Synthetic epothilone analogs with modifications in the northern hemisphere and the heterocyclic side-chain-synthesis and biological evaluation. Proceedings of ECSOC-4, Sept. 1-30, 2000, http //www.mdpi.org/ecsoc-4.htm. [Pg.94]

Slowly exchangeable NH protons either in the peptide backbone or on heterocyclic side chains, which indicate either hydrogen bonding or inaccessibility to solvent, or both, as discussed in Section 4(e)(i). [Pg.54]

Alkaline-eatalyzed elimination of hydrogen chloride irt 116 afforded the cyclic azomethine 117. The latter compound did not cyclize to the corresponding spiroaminoketal, thus demonstrating the trans orientation of the C-16 hydroxy group to the heterocyclic side-chain moiety at C-17. The weak negative Cotton effect of the azomethine 117 proved the 25S-configuration 73) of veralkamine and its derivatives. [Pg.27]

Although a wide variety of heterocycle/side-chain combinations can be used in the Boulton-Katritzky rearrangement, among these, the most commonly used heterocycle has been the 1,2,4-oxadiazole. This is due to the relative ease with which it is synthesized as well as the fact that it has a very low index of aromaticity. Its heightened chemical reactivity has made it an important target for medicinal and materials chemists and the subject of multiple reviews in the last several years. ... [Pg.530]

Matsuya, Y, Hori, A., Kawamura, T, Eman, H.F., Ahmed, K., Yu, D.-Y, Kondo, T, Toyooka, N., and Nemoto, H. (2010) Synthesis of macrosphelides containing a heterocyclic side chain as a novel apoptosis inducer. Heterocydes, 80, 579-591. [Pg.574]

Figure 3.5 Epo B analogs with fused heterocyclic side chains. Figure 3.5 Epo B analogs with fused heterocyclic side chains.
Homologization-rearrangement of N-heterocyclic side chains Allenes from acetylene derivatives Cyclic tert. amines from cyclimmonium salts by selective hydrogenation... [Pg.110]


See other pages where Heterocycle side chains is mentioned: [Pg.5]    [Pg.32]    [Pg.154]    [Pg.321]    [Pg.548]    [Pg.635]    [Pg.1418]    [Pg.233]    [Pg.269]    [Pg.19]    [Pg.235]    [Pg.257]    [Pg.271]    [Pg.278]   


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Five-membered heterocycles side-chain reactivity

Heterocycle-bearing side chain

Heterocyclic side chains

Heterocyclic side chains

Side-chain metallation five-membered heterocycles

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