Recent advancements in biotechnology are remarkable. The draft version of the human genome has been sequenced, and functional analysis of the genome is being performed vigorously. The functional analysis of peptides, and novel peptide syntheses are increasingly being used for the discovery of new biological activity.
Studies for effective synthesis of peptides are being conducted and excellent additives and coupling agents are being developed. HOAt is a 7-aza derivative of 1-hydroxybenzotriazole which is most commonly used in peptide syntheses. It has the ability to prevent the racemization of peptides when combined with a coupling agent such as DCC. BOP is an excellent coupling agent for solid peptide synthesis. Typical reagents used in peptide syntheses are shown below.

Coupling Reactions

Protective Reagents

Coupling Reactions

C0119	O0200	B2771
C1379	C1375	C0793
E0363	D1601	H1208
B1774	B1651	D1114
N0634	C1408	C1639
C1651	C0903	C1676
D3262	D2201	D2919
B1213	D1662	C1242
D2159	C1415	D1672
D0436	D0437	D0254
T2224	E0219	H0528
H0395	B0249	C1988
A1861	B1657	B1658
N0220	P0919

C0119	1,1'-Carbonylbis-1H-imidazole [Coupling Agent for Peptides Synthesis]
O0200	1,1'-Oxalyldiimidazole
B2771	1,3-Bis(2,2-dimethyl-1,3-dioxolan-4-ylmethyl)carbodiimide (This product is only available for selling domestically in Japan)
C1379	1-(Chloro-1-pyrrolidinylmethylene)pyrrolidinium Hexafluorophosphate
C1375	1-(Chloro-1-pyrrolidinylmethylene)pyrrolidinium Tetrafluoroborate
C0793	1-Cyclohexyl-3-(2-morpholinoethyl)carbodiimide Metho-p-toluenesulfonate [for Peptide Synthesis]
E0363	1-Ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline
D1601	1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide Hydrochloride [Coupling Agent for Peptides Synthesis]
H1208	1-Hydroxybenzotriazole-6-carboxamidomethyl Polystyrene Resin cross-linked with 1% DVB (50-100mesh) (1.3-1.5mmol/g)
B1774	1H-Benzotriazol-1-yloxytripyrrolidinophosphonium Hexafluorophosphate [Coupling Reagent for Peptide]
B1651	1H-Benzotriazol-1-yloxytris(dimethylamino)phosphonium Hexafluorophosphate [Coupling Reagent for Peptide]
D1114	2,2'-Dipyridyl Disulfide [for Peptide Synthesis]
N0634	2-(5-Norbornene-2,3-dicarboximido)-1,1,3,3-tetramethyluronium Tetrafluoroborate [Coupling Reagent for Peptide]
C1408	2-Chloro-1,3-dimethylimidazolinium Chloride
C1639	2-Chloro-1,3-dimethylimidazolinium Chloride (ca. 25% in Dichloromethane)
C1651	2-Chloro-1,3-dimethylimidazolinium Hexafluorophosphate
C0903	2-Chloro-1-methylpyridinium Iodide
C1676	2-Chloro-4,6-dimethoxy-1,3,5-triazine
D3262	3-(Diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one
D2201	4,6-Diphenylthieno[3,4-d]-1,3-dioxol-2-one 5,5-Dioxide
D2919	4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium Chloride Hydrate
B1213	Bis(2-oxo-3-oxazolidinyl)phosphinic Chloride
D1662	Di(N-succinimidyl) Carbonate
C1242	Diethyl Cyanophosphonate
D2159	Dimethylthiophosphinic Chloride
C1415	Diphenylphosphinic Chloride
D1672	Diphenylphosphoryl Azide
D0436	N,N'-Dicyclohexylcarbodiimide [for Peptide Synthesis]
D0437	N,N'-Dicyclohexylcarbodiimide (25% in Pyridine, ca. 1.2mol/L)
D0254	N,N'-Diisopropylcarbodiimide
T2224	N,N,N',N'-Tetramethyl-O-(N-succinimidyl)uronium Tetrafluoroborate
E0219	N-Ethyl-5-phenylisoxazolium-3'-sulfonate
H0528	N-Hydroxy-5-norbornene-2,3-dicarboximide [for Peptide Synthesis]
H0395	N-Hydroxyphthalimide
B0249	N-Hydroxysuccinimide
C1988	O-(6-Chlorobenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium Hexafluorophosphate
A1861	O-(7-Azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium Tetrafluoroborate
B1657	O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium Hexafluorophosphate [Coupling Reagent for Peptide]
B1658	O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium Tetrafluoroborate [Coupling Reagent for Peptide]
N0220	p-Nitrophenol
P0919	Pentafluorophenol

Protective Reagents

B1969	D1463	B0988
B1089	N0363	F0197
F0239	B3021	C0176
C1591	C1574	D1547
P1277	P1281	C1131
C1124	C0683	B0916

B1969	1-tert-Butoxycarbonyl-1,2,4-triazole
D1463	2,4-Dinitrophenylsulfenyl Chloride
B0988	2-(tert-Butoxycarbonyloxyimino)-2-phenylacetonitrile
B1089	2-Boc-thio-4,6-dimethylpyrimidine [Boc Agent for Peptides Synthesis]
N0363	2-Nitrophenylsulfenyl Chloride [N-Protecting Agent for Peptides Research]
F0197	9-Fluorenylmethyl Chloroformate [N-Protecting Agent for Peptides Research]
F0239	9-Fluorenylmethyl N-Succinimidyl Carbonate
B3021	Benzyl Chloroformate
C0176	Benzyl Chloroformate (30-35% in Toluene)
C1591	Carbonic Acid Benzyl 4-Nitrophenyl Ester
C1574	Carbonic Acid tert-Butyl 2,4,5-Trichlorophenyl Ester
D1547	Di-tert-butyl Pyrocarbonate [Boc-reagent for Amino Acid]
P1277	Diallyl Pyrocarbonate
P1281	Dibenzyl Pyrocarbonate
C1131	N-(2-Chlorobenzyloxycarbonyloxy)succinimide
C1124	N-Carbobenzoxyoxysuccinimide
C0683	N-Ethoxycarbonylphthalimide [for Peptide synthesis]
B0916	N-tert-Butoxycarbonylimidazole