A method for preparing a cyclic peptide, derivative or analogue thereof is described. The method comprises contacting a peptide, derivative or analogue thereof with a fluoro-heteroaromatic compound to cyclise the peptide, derivative or analogue thereof.

An improved method of coupling amino acids into peptides or peptidomimetics is disclosed in which the activation and coupling are carried out in the same vessel, in the presence of a carbodiimide in an amount greater than 1 equivalent as compared to the amino acid, in the presence of an activator additive, and at a temperature greater than 30 C.

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.

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.

Provided are antibody conjugates, including a pair of cysteines crosslinked via a two-carbon bridge covalently connecting the sulfur atoms of the cysteines. Methods for making and using antibody conjugates are also provided. The compositions and methods of the present disclosure although particularly well suited to antibodies can be extended to other analytes having sulfur moieties such as proteins obtained from biological or artificial sources.

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

An improved method for coupling carboxylic acids and amines is disclosed that includes the steps of combining a hyper-acid sensitive linker connecting an amine and a resin, a carboxylic acid, a carbodiimide, an activator additive, and a base, and carrying out the activation and coupling at a temperature greater than 30 C.

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.