The invention belongs to the field of preparation of
methylene bridge polypeptides, and particularly relates to a preparation method of
methylene bridge polypeptides, which comprises the following steps: synthesizing a naked
peptide, taking dichloro resin as a
solid phase carrier,
cutting resin
peptide by adopting TFA
cutting liquid after synthesis is completed, and carrying out
diethyl ether sedimentation centrifugation and freeze-
drying treatment to obtain the naked
peptide with the molecular weight of 833.4 + / -0.5. Therefore, through a-S-CH-S-
methylene bridge structure constructed by taking
diiodomethane as a
methylene bridge forming
reagent, the effects of remarkably improving the
chemical stability, reduction resistance and enzymolysis resistance of the polypeptide are achieved, and the problems that a
disulfide bond formed by traditional sulfydryl crosslinking is easy to break in an in-vivo reduction environment, and the potential safety
hazard is caused are solved. The core problems of insufficient polypeptide stability and difficulty in long-acting maintenance of
biological activity caused by the fact that the polypeptide is not stable in the prior art are solved, and the effects of guaranteeing high purity and
structural integrity of the naked peptide and specificity and
controllability of
methylene bridge formation reaction are achieved, so that the problems that in traditional polypeptide synthesis, sequences are prone to error, many
impurity residues exist, modification reaction selectivity is poor, and by-products are prone to being generated are solved.