The invention relates to a method for peptide synthesis, wherein said method comprises the steps of reacting a first amino acid or a first peptide with an α-amine protected second amino acid in a solvent selected from the group consisting of water, alcohol, and a mixture of water and alcohol, and removing the α-amine protecting group with a deprotecting solution. The invention further relates to protective agents, their use and an apparatus for carrying out a method for solid phase synthesis of peptides.

The invention relates to a method for peptide synthesis, wherein said method comprises the steps of reacting a first amino acid or a first peptide with an α-amine protected second amino acid in a solvent selected from the group consisting of water, alcohol, and a mixture of water and alcohol, and removing the α-amine protecting group with a deprotecting solution. The invention further relates to protective agents, their use and an apparatus for carrying out a method for solid phase synthesis of peptides.

There is provided an α-carbonyl alkenyl ester and a preparation method therefor, and the α-carbonyl alkenyl ester is further used to react with a primary or secondary amine to prepare an amide. The two reactions are combined to develop an amide bond and peptide bond formation method that directly use carboxylic acids and amines as starting materials and allenones as a condensing reagent. The α-carbonyl alkenyl ester corresponding to an α-amino acid serves as a peptide synthesis building block and is used in solid phase peptide synthesis. The method is carried out under mild reaction conditions, simple to operate, and has a high yield. Compared with existing amide bond condensation reagents, the allenones have the advantages of being simple to prepare, having good stability, a low molecular weight, not racemizing when activating α-chiral carboxylic acids, and is a novel amide bond and peptide bond condensing reagent.

Methods for the synthesis of arginine-containing peptides are provided. The methods include a deprotection step that minimizes the transfer of by-products deriving from cleaved sulfonyl-5 based side chain protecting groups from arginine to amino acids carrying electron rich side chains.

An object of the present invention is to provide a method for producing a peptide with high purity and high efficiency, a protective group-forming reagent having excellent deprotective properties, and a novel condensed polycyclic compound. According to the present invention, there are provided a method for producing a peptide including a step of using a polycyclic compound represented by Formula (1), a protective group-forming reagent containing the polycyclic compound, and the polycyclic compound. At least one of R.sup.1 to R.sup.8 and R.sup.110 has R.sup.A, R.sup.A represents an aliphatic hydrocarbon group or an organic group having an aliphatic hydrocarbon group, and at least one aliphatic hydrocarbon group has 3 or more carbon atoms.

##STR00001##

Methods for the synthesis of arginine-containing peptides are provided. The methods include a deprotection step that minimizes the transfer of by-products deriving from cleaved sulfonyl-5 based side chain protecting groups from arginine to amino acids carrying electron rich side chains.

The present invention relates to a method for the synthesis of a polypeptide comprising a pre-determined amino acid sequence. The method according to the invention comprises coupling cycles of coupling an N-terminally protected amino acid building block C-terminally at an unprotected N-terminal amino group of an amino acid chain, wherein at least one coupling cycle comprises a coupling step (a), a capping step (b), and a de-protecting step (c).

To develop a protecting group that facilitates separation and purification, after reaction, of a compound including a protected functional group, without solidifying or insolubilizing the compound. A xanthene compound of by General Formula (1) ##STR00001## (wherein Y is OR.sup.17 (R.sup.17 is a hydrogen atom or an active ester-protecting group), NHR.sup.18 (R.sup.18 is a hydrogen atom, or a linear or branched C.sub.1-C.sub.6 alkyl group or aralkyl group), an azide, a halogen atom, or a carbonyl group formed together with a methylene group; at least one of R.sup.1 to R.sup.8 is represented by Formula (2);
OR.sup.9X-A(2) and a residue is a hydrogen atom, a halogen atom, a C.sub.1-C.sub.4 alkyl group, or a C.sub.1-C.sub.4 alkoxy group, wherein R.sup.9 is a linear or branched C.sub.1-C.sub.16 alkylene group; X is O or CONR.sup.19 (R.sup.19 is a hydrogen atom or a C.sub.1-C.sub.4 alkyl group); and A is represented by Formula (3) or the like ##STR00002## (wherein R.sup.10, R.sup.11, and R.sup.12, the same or different, are a linear or branched C.sub.1-C.sub.6 alkyl group or an aryl group optionally including a substituent; R.sup.13 is a single bond or a linear or branched C.sub.1-C.sub.3 alkylene group; and R.sup.14, R.sup.15, and R.sup.16 are a linear or branched C.sub.1-C.sub.3 alkylene group)).

The present invention relates to a method for the synthesis of a polypeptide comprising a pre-determined amino acid sequence. The method according to the invention comprises coupling cycles of coupling an N-terminally protected amino acid building block C-terminally at an unprotected N-terminal amino group of an amino acid chain, wherein at least one coupling cycle comprises a coupling step (a), a capping step (b), and a de-protecting step (c).

To develop a protecting group that facilitates separation and purification, after reaction, of a compound including a protected functional group, without solidifying or insolubilizing the compound.

A xanthene compound of by General Formula (1)

##STR00001## (wherein Y is OR.sup.17 (R.sup.17 is a hydrogen atom or an active ester-protecting group), NHR.sup.18 (R.sup.18 is a hydrogen atom, or a linear or branched C.sub.1-C.sub.6 alkyl group or aralkyl group), an azide, a halogen atom, or a carbonyl group formed together with a methylene group; at least one of R.sup.1 to R.sup.8 is represented by Formula (2);

OR.sup.9X-A(2) and a residue is a hydrogen atom, a halogen atom, a C.sub.1-C.sub.4 alkyl group, or a C.sub.1-C.sub.4 alkoxy group, wherein R.sup.9 is a linear or branched C.sub.1-C.sub.16 alkylene group; X is O or CONR.sup.19 (R.sup.19 is a hydrogen atom or a C.sub.1-C.sub.4 alkyl group); and A is represented by Formula (3) or the like

##STR00002## (wherein R.sup.10, R.sup.11, and R.sup.12, the same or different, are a linear or branched C.sub.1-C.sub.6 alkyl group or an aryl group optionally including a substituent; R.sup.13 is a single bond or a linear or branched C.sub.1-C.sub.3 alkylene group; and R.sup.14, R.sup.15, and R.sup.16 are a linear or branched C.sub.1-C.sub.3 alkylene group)).