An improved method for coupling amino acids into peptides or peptidomimetics is disclosed that includes the steps of combining an amino acid, a carbodiimide, an activator additive, and a base at less than 1 equivalent compared to the amino acid to be activated; and carrying out the activation and coupling at a temperature greater than 30° C.

Methods and system for solid phase peptide synthesis are provided. Solid phase peptide synthesis is a known process in which amino acid residues are added to peptides that have been immobilized on a solid support. New amino acid residues are added via a coupling reaction between an activated amino acid and an amino acid residue of the immobilized peptide. Amino acids may be activated using, e.g., a base and an activating agent. Certain inventive concepts, described herein, relate to methods and systems for the activation of amino acids. These systems and methods may allow for fewer side reactions and a higher yield compared to conventional activation techniques as well as the customization of the coupling reaction on a residue-by-residue basis without the need for costly and/or complex processes.

The present disclosure relates to site-selective labeling compounds, and methods of using such compounds.

The present disclosure provides a method of solid-phase peptide synthesis from the N terminus to C terminus without detectable epimerization of the C-terminal amino acid. The method includes using derivatized amino acids comprising a diamino-aryl group.

The present invention relates to the field of medicinal synthesis, and discloses a method for synthesizing degarelix. The method of the present invention as a whole divides the synthesis of degarelix into two parts from amino acids at positions 5 and 6, employs proper protective groups in part of the protected amino acids therein, and finally uses in association with a specific acidolysis agent to complete the whole synthesis process. In the present invention, a proper synthesizing scheme is selected, and adaptive protective group and acidolysis agent are selected, so that the overall synthesis process is optimized, the purity of degarelix is significantly improved with a higer total yield, and the production of the toxic hydantoin degradation product is avoided.

A method for producing an amide, including mixing a first composition containing a carboxylic acid or a carboxylic acid active species, and an organic solvent and a second composition containing an amine having at least one carboxyl group and water and causing the carboxylic acid or the carboxylic acid active species to react with the amine to obtain an amide.

Disclosed herein is an improved process for preparing abaloparatide. The process generally utilizes solid phase peptide synthesis employing an Fmoc-protection scheme. Incorporating a systematic recoupling step of a glutamine residue (Gln.sup.16) has been found to minimize the formation of an undesirable des-Gln.sup.16 abaloparatide impurity, which is often obtained in significant quantities in the conventional process.

Disclosed is a new process and intermediates for preparing dipyrrolidine peptide compounds such as, for example, rapastinel. Advantageously, the process may be industrially scalable and cost-effective and use less toxic reagents and/or solvents. Further, the process may be used to prepare peptide compounds having improved purity.

A method for producing an amide includes: reacting arginines, arginine derivatives or arginine analogs in which two amino groups or imino groups in the side chain are protected by protecting groups with a halogenated formate ester and then reacting with an amine.

Methods and system for solid phase peptide synthesis are provided. Solid phase peptide synthesis is a known process in which amino acid residues are added to peptides that have been immobilized on a solid support. New amino acid residues are added via a coupling reaction between an activated amino acid and an amino acid residue of the immobilized peptide. Amino acids may be activated using, e.g., a base and an activating agent. Certain inventive concepts, described herein, relate to methods and systems for the activation of amino acids. These systems and methods may allow for fewer side reactions and a higher yield compared to conventional activation techniques as well as the customization of the coupling reaction on a residue-by-residue basis without the need for costly and/or complex processes.