SOLID-PHASE SYNTHESIS OF BETA-AMYLOID(1-4 2)

A solid phase synthesis of the polypeptide corresponding to the 1-42 s equence of beta-amyloid protein that accumulated in brain cells during Alzheimer's disease was performed using Fmoc strategy. Two alternativ e approaches to the synthesis, stepwise elongation of the peptide chai n and fragment coupling, were compared, and the advantage of the latte r approach was shown. Effects of various factors (solvents, reagents f or deprotection of alpha-amino functions, and substitution level of po lymer carrier) on the synthesis was studied. The appropriate condition s of HPLC for an analysis of the homogeneity bf the beta A4(1-42) pept ide, as well as the conditions of its gel chromatography on Sephadex G -50 providing the preparation of the end product of 90-95% purity acco rding to HPLC were found.