Method for preparing a peptide assembly of n fragments and n1 amino acids bearing a thiol function, represented by the formula:
A.sub.1-C.sub.1-A.sub.2-C.sub.2-A.sub.3- . . . -C.sub.i1-A.sub.i- . . . -C.sub.n1-A.sub.n(I)
in which A.sub.1, A.sub.2, A.sub.3, . . . A.sub.i . . . , A.sub.n are peptide fragments, C.sub.1, C.sub.2, C.sub.3 . . . C.sub.i1 . . . C.sub.n1 are amino acid residues bearing a thiol function, n is comprised between 3 and 50, and i is 2 to n, in which a peptide-thioester is prepared of formula: A.sub.1-SR (II) in which A.sub.1 is a peptide fragment and SR is an alkyl thioester residue, R being alkyl optionally substituted, starting from a bis(2-sulphanylethyl)amino peptide.

The present invention has an object of providing a peptide synthesis method using a carrier capable of reversibly repeating the dissolved state and the insolubilized state, wherein the problem of an amino acid active species existing in the reaction system in de-protection reaction can be easily solved. The present invention provides a peptide synthesis method comprising the following steps: a step of condensing an N-Fmoc protected amino acid with a peptide having a C-terminal protected with a carrier which is crystallized according to a change of a composition of a dissolving solvent, in the presence of a condensing agent, to obtain an N-Fmoc-C-carrier protected peptide, a step of adding an alkylamine having 1 to 14 carbon atoms or hydroxyl amine to the reaction system, a step of de-protecting the N-terminal, and a step of changing the composition of the solvent dissolving the C-carrier protected peptide, to crystallize and separate the peptide.

The present invention provides a means for producing a peptide with a small number of steps in a short time. One aspect of the present invention relates to a method for producing a peptide, comprising: a C-terminal activation step of introducing an N-terminally protected amino acid or peptide, in which an N-terminal amino group is protected by an N-terminal protecting group, and a C-terminal activator into a flow reactor, thereby activating a C-terminal carboxyl group of the N-terminally protected amino acid or peptide in the flow reactor to form a C-terminally activated derivative of the N-terminally protected amino acid or peptide; a condensation step of introducing the C-terminally activated derivative of the N-terminally protected amino acid or peptide and a C-terminally protected amino acid or peptide, in which a C-terminal carboxyl group is protected by a tag protecting group, into a flow reactor, thereby condensing the N-terminally protected amino acid or peptide with the C-terminally protected amino acid or peptide on the N-terminal side in the flow reactor to form an N-terminally and C-terminally protected peptide extended N-terminally; an N-terminal deprotection step of introducing the N-terminally and C-terminally protected peptide extended N-terminally and a deprotecting agent for an N-terminal protecting group into a flow reactor, thereby removing the N-terminal protecting group for deprotection in the flow reactor to form a C-terminally protected peptide extended N-terminally; and an extraction step of mixing a reaction mixture containing the C-terminally protected peptide extended N-terminally with an aqueous phase to extract the C-terminally protected peptide extended N-terminally into an organic phase. Another aspect of the present invention relates to an apparatus for producing a peptide.

The instant disclosure is directed to solution phase fragment coupling methods for preparing etelcalcetide and its pharmaceutically acceptable salts.

The present disclosure relates to a novel spherical agglomeration method for proteins, and protein particles made by the spherical agglomeration method. By using continuous oscillatory baffled crystallizer, the method of the present disclosure is capable of maintain the biologically activities and providing protein particles with an average particle size between 1-500 m.

The present invention relates to Bicycle toxin conjugates, methods for preparation, and methods of use for treating cancer.

The subject matter of the present invention is peptide C.sup.-amides which are precursors of peptide C.sup.-thioesters, characterized in that they comprise the radical of general formula (I) in which X, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, n and A are as defined in Claim 1. The subject matter of the present invention is also the use of these peptide C.sup.-amides for obtaining peptide C.sup.-thioesters. The subject matter of the present invention is also the use of these peptide C.sup.-amides for obtaining peptides or proteins, in particular of therapeutic interest, by direct use as a crypto-thioester partner in NCL reactions. ##STR00001##

Method for enzymatically synthesizing an oligopeptide, comprising the coupling of an (optionally N-protected) protected oligopeptide ester with an (optionally C-protected) protected oligopeptide nucleophile in an organic solvent or an organic solvent mixture having a water content of 0.1 vol % or less, by a subtilisin in any possible form.

Novel hybrid polymers are disclosed that have a structure represented by the following formula I:

##STR00001##

wherein Abiotic oligomer, Polypeptide, X, Y, and R.sup.1 are as described herein. The methods to prepare the hybrid polymers via novel oxazolidinyl compounds are also described.

It was found that a peptide compound that has an N-substituted-,-disubstituted amino acid residue at the N-terminus and containing a dipeptide residue in which the N-substituted-,-disubstituted amino acid residue and an N-substituted amino acid residue are linked together, can be efficiently produced by linking an N-unsubstituted-,-disubstituted amino acid whose amino group is protected with an electron-withdrawing protecting group to an N-substituted amino acid or a peptide compound having an N-substituted amino acid residue at the N-terminus, and then allowing a substituent-introducing agent to act in the presence of a specific base to selectively introduce a substituent to the amino group at the N-terminus.