Synthesis and comparative properties of two amide‐generating resin linkers for use in solid phase peptide synthesis
Well‐characterized resins of high purity are critical for effective solid phase peptide synthesis (SPPS). The quality of commercial (4‐methyl)benzhydrylamine‐resin (MBHA‐resin), used for the synthesis of peptide amides, is not consistent and residual ketone functionalities are frequently present. Such ketone or aldehyde impurities lead to the formation of acylation‐resistant deletion peptides in SPPS. To avoid these undesirable side reactions, we have optimized the preparation of two amide‐generating linkers, which, in combination with aminomethyl‐resin prepared directly from polystyrene resin, serve as alternatives to MBHA‐resin for peptide amide synthesis. Then we have explored their comparative properties in SPPS. Use of sonication in reductive amination facilitated the synthesis of both benzhydrylamine (BHA) and MBHA linkers. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
A Single Pseudoproline and Microwave Solid Phase Peptide Synthesis Facilitates an Efficient Synthesis of Human Amylin 1–37
A chemical synthesis of the 37 residue polypeptide human amylin using microwave enhanced solid phase peptide chemistry is described. An optimised protocol used only a single pseudoproline derivative, a chemically pure resin and single couplings of all amino acids to deliver non-oxidised amylin in high yield. Oxidation of the crude peptide to form the disulfide bond was accomplished in 20 min using 2,2′-dipyridyl disulfide in dimethyl sulphoxide giving human amylin that was fully functional in a cAMP assay.
Synthesis of quasi-stationary inhomogeneous impedance body of arbitrary shape
Formulas were obtained for the reflection factors of a plane wave from the inhomogeneous impedance plane, which reflects the incident wave in the given direction. The problem of synthesis of impedance inhomogeneous rotation body was solved for an arbitrary shaped generatrix for the given scattering diagram for co- and cross polarizations. Impedance distributions were obtained in explicit form. Restrictions on the class of implementable scat- terplots were formulated.