52434-75-0

Basic information

• Product Name: LHRH (1-5)
• Synonyms: LHRH (1-5);PGLU-HIS-TRP-SER-TYR;PYR-HIS-TRP-SER-TYR-OH;LHRH (1-5), free acid
• CAS NO: 52434-75-0
• Molecular Formula: C₃₄H₃₈N₈O₉
• Molecular Weight: 702.71
• Mol File: 52434-75-0.mol
• Article Data: 2

Chemical Properties

• Appearance: /
• CAS DataBase Reference: LHRH (1-5)(CAS DataBase Reference)
• NIST Chemistry Reference: LHRH (1-5)(52434-75-0)
• EPA Substance Registry System: LHRH (1-5)(52434-75-0)

Safety Data

• Hazardous Substances Data: 52434-75-0(Hazardous Substances Data)

Usage

General Description

LHRH (1-5) refers to the first five amino acids of the luteinizing hormone-releasing hormone, also known as gonadotropin-releasing hormone (GnRH). This peptide hormone plays a key role in the regulation of reproductive function by stimulating the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary gland. The first five amino acids of the LHRH sequence, namely leucine, histidine, arginine, proline, and glycine, are essential for its biological activity and are involved in binding to its receptor on the pituitary gland. Studies have shown that synthetic analogs of LHRH (1-5) can be used to manipulate the reproductive system and may have potential applications in the treatment of hormone-related disorders and infertility.

Synthetic route

L-pyroglutamyl-L-histidyl-L-trypthophyl-L-seryl-L-tyrosine tert-butyl ester (142822-22-8) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
With methoxybenzene; trifluoroacetic acid at 0℃; for 3h;

O-benzyl-N-tert-butoxycarbonyl-L-tyrosine (2130-96-3) + BOC-O-benzyl-L-serine (23680-31-1) + Boc-Trp-OH (13139-14-5) + Boc-His(Dnp)-OH (25024-53-7) + pGlu → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Yield given. Multistep reaction;

Tyr(tBu) (16874-12-7) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Multi-step reaction with 4 steps 1: 78 percent / dioxane / 5 h / papain, dithioerythritol in phosphate buffer, pH 9 2: deprotection 3: 67 percent / methanol; H2O / 16 h / Ambient temperature; papain, dithioerythritol, pH 8 4: TFA, anisole / 3 h / 0 °C View Scheme

L-seryl-L-tyrosine tert-butyl ester (142822-21-7) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: 67 percent / methanol; H2O / 16 h / Ambient temperature; papain, dithioerythritol, pH 8 2: TFA, anisole / 3 h / 0 °C View Scheme

N-benzyloxycarbonyl-L-seryl-L-tyrosine tert-butyl ester (142822-20-6) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Multi-step reaction with 3 steps 1: deprotection 2: 67 percent / methanol; H2O / 16 h / Ambient temperature; papain, dithioerythritol, pH 8 3: TFA, anisole / 3 h / 0 °C View Scheme

L-Pyroglutamyl-L-histidine Methyl Ester (25575-88-6) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Multi-step reaction with 3 steps 1: 75 percent / CH2Cl2; H2O / 16 h / Ambient temperature; α-chymotrypsin 2: 67 percent / methanol; H2O / 16 h / Ambient temperature; papain, dithioerythritol, pH 8 3: TFA, anisole / 3 h / 0 °C View Scheme

L-tryptophanamide (20696-57-5) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Multi-step reaction with 3 steps 1: 75 percent / CH2Cl2; H2O / 16 h / Ambient temperature; α-chymotrypsin 2: 67 percent / methanol; H2O / 16 h / Ambient temperature; papain, dithioerythritol, pH 8 3: TFA, anisole / 3 h / 0 °C View Scheme

L-pyroglutamyl-L-histidine-L-tryptophane amide (33217-51-5) → pGlu-His-Trp-Ser-Tyr (52434-75-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: 67 percent / methanol; H2O / 16 h / Ambient temperature; papain, dithioerythritol, pH 8 2: TFA, anisole / 3 h / 0 °C View Scheme

methanol (67-56-1) + pGlu-His-Trp-Ser-Tyr (52434-75-0) → L-pyroglutamyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosine methyl ester (51871-39-7)

Conditions	Yield
With boron trifluoride at 0℃; for 8h;	83%

pGlu-His-Trp-Ser-Tyr (52434-75-0) → (S)-2-{(S)-3-Hydroxy-2-[(Z)-2-{(S)-3-(1H-imidazol-4-yl)-2-[((S)-5-oxo-pyrrolidine-2-carbonyl)-amino]-propionylamino}-3-(1H-indol-3-yl)-acryloylamino]-propionylamino}-3-(4-hydroxy-phenyl)-propionic acid (207744-20-5)

Conditions	Yield
With (S)-tryptophan 2',3'-oxidase from Chromobacterium violaceum (ATCC 12472) In various solvent(s) at 30℃; for 20h;	66%

pGlu-His-Trp-Ser-Tyr (52434-75-0) → pGlu-His-[2',3'-2H]-Trp-Ser-Tyr

Conditions	Yield
Multi-step reaction with 2 steps 1: 66 percent / (S)-tryptophan 2',3'-oxidase from Chromobacterium violaceum (ATCC 12472) / various solvent(s) / 20 h / 30 °C 2: 95 percent / 2H2 / PdO / methanol / 20 h / 20 °C / 3800 Torr View Scheme

pGlu-His-Trp-Ser-Tyr (52434-75-0) → pGlu-His-[2',3'-2H]-(S)Trp-Ser-Tyr

Conditions	Yield
Multi-step reaction with 2 steps 1: 66 percent / (S)-tryptophan 2',3'-oxidase from Chromobacterium violaceum (ATCC 12472) / various solvent(s) / 20 h / 30 °C 2: 72 percent / 2H2 / / methanol / 20 h / 20 °C / 11400 Torr View Scheme

pGlu-His-Trp-Ser-Tyr (52434-75-0) → L-pyroglutamyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosyl-glycyl-L-leucyl-L-arginyl-L-prolyl-glycine amide hydrochloride (51952-40-0, 51952-41-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: 83 percent / 10percent BF3 / 8 h / 0 °C 2: 84 percent / dimethylformamide / 1 h / Ambient temperature; α-chymotrysin, 0.2M carbonate buffer, pH 8 View Scheme

Upstream product

• 142822-22-8 L-pyroglutamyl-L-histidyl-L-trypthophyl-L-seryl-L-tyrosine tert-butyl ester 
• 2130-96-3 O-benzyl-N-tert-butoxycarbonyl-L-tyrosine 
• 23680-31-1 BOC-O-benzyl-L-serine 
• 13139-14-5 Boc-Trp-OH 
• 25024-53-7 Boc-His(Dnp)-OH 
• 16874-12-7 Tyr(tBu) 
• 142822-21-7 L-seryl-L-tyrosine tert-butyl ester 
• 142822-20-6 N-benzyloxycarbonyl-L-seryl-L-tyrosine tert-butyl ester 
• 25575-88-6 L-Pyroglutamyl-L-histidine Methyl Ester 
• 20696-57-5 L-tryptophanamide 
• 33217-51-5 L-pyroglutamyl-L-histidine-L-tryptophane amide 

Downstream Products

• 51871-39-7 L-pyroglutamyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosine methyl ester 
• 207744-20-5 (S)-2-{(S)-3-Hydroxy-2-[(Z)-2-{(S)-3-(1H-imidazol-4-yl)-2-[((S)-5-oxo-pyrrolidine-2-carbonyl)-amino]-propionylamino}-3-(1H-indol-3-yl)-acryloylamino]-propionylamino}-3-(4-hydroxy-phenyl)-propionic acid 
• 51952-40-0 L-pyroglutamyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosyl-glycyl-L-leucyl-L-arginyl-L-prolyl-glycine amide hydrochloride 

Relevant articles and documents

Expedient Synthesis of Gonadotropin Releasing Hormone (GnRH) Through a Combined Chemical-Enzymatic Approach

We have developed a chemical-enzymatic synthetic approach to gonadotropin releasing hormone Glp1-His2-Trp3-Ser4-Tyr5-Gly6-Leu7-Arg8-Pro9-Gly10-NH2 (GnRH) which enables one to perform the synthesis efficiently according to minimal protection strategy with all reactive side chains of amino acids unprotected.Five peptide bonds His2-Trp3, Tyr5-Gly6, Leu7-Arg8 and Trp3-Ser4, Ser4-Tyr5 were formed by means of α-chymotrypsin and papain, respectively.The remaining four bonds Glp1-His2, Gly6-Leu7, Arg8-Pro9, Pro9-Gly10 were formed by chemical methods.The synthesis is simple to carry out and there are no problems in scaling up as demonstrated by the final coupling on 2 g scale affording highly pure GnRH in the yield of 84-90percent. Key Words: Gonadotropin Releasing Hormone, Enzymatic Peptide Synthesis, Papain, α-Chymotrypsin