The solution synthesis of sequential polypeptides as models for the double-stranded coiled-coil structure of tropomyosin

The syntheses of the three sequential polyheptapeptides [L-Leu-L-Glu-L-Ser-L-Leu-L-Glu-L-Ser-L-Lys)n, [L-Ala-L-Glu-L-Ser-L-Ala-L-Glu-L-Ser-L-Lys]n, [L-Ala-L-Glu-L-Ser-L-Leu-L-Glu-L-Ser-L-Lys]n and of the polytetrapeptide [L-Leu-L-Glu-L-Ser-L-Lys]n by solution methods are described. The syntheses were performed using a combination of a modified mixed carbonic anhydride method and an active ester coupling method. The N-hydroxysuccinimide ester was used as the active group for the polymerization of the monomers. These compounds were prepared as model polypeptides for the coiled-coil structure of tropomyosin.