Proposed is a novel method for preparing liraglutide by means of an ionic liquid and a eutectic solvent, which are environment-friendly solvents. More specifically, the method is characterized in that fractionated peptide 1 represented by the following formula (1) and fractionated peptide 2 represented by the following formula (2) are subjected to a coupling reaction in the presence of an ionic liquid or a eutectic solvent. In preparing GLP-1 analogues such as liraglutide, the present method increases reactivity when producing liraglutide, which is an unprocessed reactant, by using an ionic liquid and a eutectic solvent as environment-friendly solvents instead of using organic solvents. Accordingly, through a relatively short and simple purification process, the present method has advantages of reducing the formation of related substances, improving purity, improving yields, shortening reaction times, reducing production cost, and lowering the manufacturing cost.

Proposed is a novel method for preparing liraglutide by means of an ionic liquid and a eutectic solvent, which are environment-friendly solvents. More specifically, the method is characterized in that fractionated peptide 1 represented by the following formula (1) and fractionated peptide 2 represented by the following formula (2) are subjected to a coupling reaction in the presence of an ionic liquid or a eutectic solvent. In preparing GLP-1 analogues such as liraglutide, the present method increases reactivity when producing liraglutide, which is an unprocessed reactant, by using an ionic liquid and a eutectic solvent as environment-friendly solvents instead of using organic solvents. Accordingly, through a relatively short and simple purification process, the present method has advantages of reducing the formation of related substances, improving purity, improving yields, shortening reaction times, reducing production cost, and lowering the manufacturing cost.

The present invention relates to the chemical synthesis of amanin and its derivatives. The present invention also relates to intermediate products of the amanin synthesis.

The present invention relates to the chemical synthesis of amanin and its derivatives. The present invention also relates to intermediate products of the amanin synthesis.

The present disclosure relates generally to therapeutic agents that may be useful as modulators of Integrated Stress Response (ISR) pathway.

The present disclosure relates generally to therapeutic agents that may be useful as modulators of Integrated Stress Response (ISR) pathway.

Embodiments of the present disclosure pertain to methods of conjugating a molecule to a polypeptide by (1) modifying one or more thiol residues on the polypeptide, where the modifying includes cyanylation of the one or more thiol residues; and (2) associating the polypeptide with the molecule, where the associating results in the conjugation of the molecule to the polypeptide through a reaction between a nucleophilic moiety on the molecule and the one or more modified thiol residues. The cyanylation may include attachment of cyano groups to sulfur atoms of the one or more thiol residues to form thiocyanato groups that undergo reversible intramolecular addition with a nearby N-amide group to generate a 1-acyl-2-iminothiazolidine intermediate. Thereafter, the nucleophilic moiety on the molecule reacts with the 1-acyl-2-iminothiazolidine intermediate to replace 2-iminothiazolidine in a nucleophilic acyl substitution reaction and result in the conjugation of the molecule to the polypeptide.

Embodiments of the present disclosure pertain to methods of conjugating a molecule to a polypeptide by (1) modifying one or more thiol residues on the polypeptide, where the modifying includes cyanylation of the one or more thiol residues; and (2) associating the polypeptide with the molecule, where the associating results in the conjugation of the molecule to the polypeptide through a reaction between a nucleophilic moiety on the molecule and the one or more modified thiol residues. The cyanylation may include attachment of cyano groups to sulfur atoms of the one or more thiol residues to form thiocyanato groups that undergo reversible intramolecular addition with a nearby N-amide group to generate a 1-acyl-2-iminothiazolidine intermediate. Thereafter, the nucleophilic moiety on the molecule reacts with the 1-acyl-2-iminothiazolidine intermediate to replace 2-iminothiazolidine in a nucleophilic acyl substitution reaction and result in the conjugation of the molecule to the polypeptide.

Disclosed are an etelcalcetide intermediate and a method for synthesizing etelcalcetide. The etelcalcetide intermediate is Fmoc-D-Cys(S—S—(N-Boc)-L-Cys(OtBu))-OH. The method for synthesizing the etelcalcetide includes the following steps: using N-Boc-L-Cqs-OtBu as a starting material to generate a primary product of a formula (A) by means of a substitution reaction, herein R is S-Py or Cl; and performing a coupling reaction on the primary product and Fmoc-D-Cys-OH amino acid to obtain Fmoc-D-Cys(S—S—(N-Boc)-L-Cys(OtBu))-OH. The key intermediate is used for synthesizing the etelcalcetide, which may improve the purity and the yield. It is important that the raw materials for synthesizing the key intermediate are cheap and readily available, and the process is simple.

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Disclosed are an etelcalcetide intermediate and a method for synthesizing etelcalcetide. The etelcalcetide intermediate is Fmoc-D-Cys(S—S—(N-Boc)-L-Cys(OtBu))-OH. The method for synthesizing the etelcalcetide includes the following steps: using N-Boc-L-Cqs-OtBu as a starting material to generate a primary product of a formula (A) by means of a substitution reaction, herein R is S-Py or Cl; and performing a coupling reaction on the primary product and Fmoc-D-Cys-OH amino acid to obtain Fmoc-D-Cys(S—S—(N-Boc)-L-Cys(OtBu))-OH. The key intermediate is used for synthesizing the etelcalcetide, which may improve the purity and the yield. It is important that the raw materials for synthesizing the key intermediate are cheap and readily available, and the process is simple.

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