53634-19-8Relevant academic research and scientific papers
IMPROVEMENTS IN SOLID PHASE PEPTIDE SYNTHESIS
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Paragraph 0071-0076, (2017/08/01)
An improved method of deprotection in solid phase peptide synthesis is disclosed. In particular the deprotecting composition is added in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated acid from the preceding coupling cycle, and without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle. Thereafter, the ambient pressure in the vessel is reduced with a vacuum pull to remove the deprotecting composition without any draining step and without otherwise adversely affecting the remaining materials in the vessel or causing problems in subsequent steps in the SPPS cycle.
Solid-phase peptide synthesis in highly loaded conditions
Nakaie, Clovis R.,Oliveira, Eliandre,Vicente, Eduardo F.,Jubilut, Guita N.,Souza, Sinval E.G.,Marchetto, Reinaldo,Cilli, Eduardo M.
experimental part, p. 101 - 109 (2011/06/25)
The use of very highly substituted resins has been avoided for peptide synthesis due to the aggravation of chain-chain interactions within beads. To better evaluate this problem, a combined solvation-peptide synthesis approach was herein developed taking as models, several peptide-resins and with peptide contents values increasing up to near 85%. Influence of peptide sequence and loading to solvation characteristics of these compounds was observed. Moreover, chain-chain distance and chain concentration within the bead were also calculated in different loaded conditions. Of note, a severe shrinking of beads occurred during the α-amine deprotonation step only when in heavily loaded resins, thus suggesting the need for the modification of the solvent system at this step. Finally, the yields of different syntheses in low and heavily loaded conditions were comparable, thus indicating the feasibility of applying this latter "prohibitive" chemical synthesis protocol. We thought these results might be basically credited to the possibility, without the need of increasing molar excess of reactants, of carrying out the coupling reaction in higher concentration of reactants - near three to seven folds - favored by the use of smaller amount of resin. Additionally, the alteration in the solvent system at the α-amine deprotonation step might be also improving the peptide synthesis when in heavily loaded experimental protocol.
Characterization of the degradation products of luteinizing hormone releasing hormone
Motto,Hamburg,Graden,Shaw,Cotter
, p. 419 - 423 (2007/10/02)
The degradation products of luteinizing hormone releasing hormone [LH/RH; 1; gonadorelin releasing hormone (GnRH); 2] were determined in aqueous solution (pH 6.5) at 25, 37, 50, and 80 °C. The predominant route of degradation involved the cleavage of the 2 to the free acid form in peptides 4 and 10. Racemization of the serine and histidine residues to give peptides 2 and 3 was a second route of degradation.
Synthesis of Gonadoliberin, a Gonadotropin Releasing Hormone
Rzeszotarska, Barbara,Masiukiewicz, Elzbieta,Kmiecik-Chmura, Halina
, p. 791 - 798 (2007/10/02)
A simple laboratory synthesis of gonadoliberin was elaborated basing on classical solution methods and using minimal protection of the side-chain functions.In the final step a hexapeptide segment was condensed with the corresponding tetrapeptide and the obtained product was purified by a single step silica gel chromatography.The total efficiency of the whole synthesis was 15percent.
Synthetic decapeptide having the activity of the luteinizing hormone releasing hormone and method for manufacturing the same
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, (2008/06/13)
A synthetic decapeptide, L-pglutamyl-L-histidyl-L-tryptophanyl-L-seryl-L-tyrosyl-glycyl-L-leucyl-L-arginyl-L-prolyl-glycinamide which has the hormonal activities of the luteinizing hormone releasing hormone (LRH) of the hypothalamus gland of mammals is produced by utilizing as the key starting materials, the amino acids, glutamic acid or pyroglutamic acid, histidine, tryptophan, serine, tyrosine, glycine, leucine, arginine, and proline. Synthesis of the decapeptide is accomplished by coupling, in appropriate combinations of appropriate protected forms of the amino acids, and finally deprotecting to yield the amide, L-pglutamyl-L-histidyl-L-tryptophanyl-L-seryl-L-tyrosyl-glycyl-L-leucyl-L-arginyl-L-prolyl-glycinamide.
Synthesis and biological activity of some analogs of the gonadotropin releasing hormone
Arnold,Flouret,Morgan,Rippel,White
, p. 314 - 319,315, 316 (2007/10/05)
Twenty one analogs of gonadotropin releasing hormone 2 (GnRH), were synthesized by the solid phase method. The derivatives were 3 (GnRH methyl ester), GnRH N methyl amide, GnRH free acid, 2 (Gn RH N terminal hexapeptide), and also [Ac Ala1], [Ac gly1], [D 1], [Pro1], [Arg2], [Tyr(Me)3], [Ser5], [des Gly6], [Sar6], [des Pro9], [des Gly10, Pro NH29], [des Gly10, Pro NHC2H59], [Tyr11], [Tyr(Me)35], [des His2, des Pro9], [des His2, Sar6], and [Sar6 des Tyr5] GnRH. All analogs were purified at both the protected and the deblocked stage. The final products were characterized by chemical and physical methods and assayed in vitro for both LH and FSH release using rat pituitaries. Those derivatives which showed less than 0.2% of the activity of GnRH itself were further tested for inhibition of gonadotropin release.
