Abstract: Solid-phase synthesis of a peptide has a problem that a desired elongation reaction is prevented from proceeding by diketopiperazine and a 6-membered diamine skeleton compound formed when a protective group at the N-terminal is removed. The present inventors have found that when in production of a peptide by a solid-phase method, a peptide in which an amino group at the N-terminal is protected with a protective group having an Fmoc skeleton is treated in a specific solvent with a base having a pKa of 23 or more in acetonitrile as a conjugate acid, and a peptide chain is then elongated, it is possible to solve the problem described above.

Abstract: The invention relates to heterocyclic sulfonamide derivatives and their use in the treatment and prophylaxis of autoimmune, inflammatory, cardiovascular, neuronal, auditory, renal and metabolic mediated diseases, and to compositions containing said derivatives and processes for their preparation.