Syntheses of dendritic branches based on l-lysine: is the stereochemistry preserved throughout the synthesis?
作者:Malcolm Driffield、David M. Goodall、David K. Smith
DOI:10.1039/b304410f
日期:——
stereochemistry in the dendritic peptide was dependent on the method of synthesis, with divergent methodology being preferred. The results are discussed in terms of the known stereochemical outcomes of traditional peptide coupling processes, and are generalised to the synthesis of other dendritic peptides. Such observations about the chirality of dendritic peptides are of relevance to chemists developing
Imidazole derivatives which are useful intermediates for the production of compounds having pharmacological activity at histamine H.sub.2 receptors. A specific compound of the present invention is 4-(4-aminobutyl)-1,3-dihydro-5-methyl-2H-imidazole-2-thione, hereinafter referred to as 4-(4-Aminobutyl)-5-methylimidazole-2-thione.
A series of benzoylated and phenylsulfonylated amino acids are novel, low molecular weight, self-assembling molecules. At low pH, these compounds form microspheres that dissolve readily under neutral conditions. In a given synthetic series, those molecules with low aqueous solubility formed microspheres more readily than did the molecules possessing high water solubility, suggesting that the hydrophobicity of these compounds contributes to the ability to form microspheres. In addition, molecular modeling studies on selected compounds have shown that microsphere formation may depend also on various aromatic ring and dipole-dipole interactions, which could effect the extent and types of favorable stacking conformations between molecules. The microspheres prepared from these compounds have been used to effect the oral delivery of salmon calcitonin, a model protein drug, in both rodents and primates.
PIPER J. R.; ROSE L. M.; JOHNSTON T. P.; GRENAN M. M., J. MED. CHEM., 1979, 22, NO 6, 631-639
作者:PIPER J. R.、 ROSE L. M.、 JOHNSTON T. P.、 GRENAN M. M.