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1.
J Med Chem ; 18(3): 284-7, 1975 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1133819

RESUMO

[1-Beta-mercapto-beta,beta-pentamethylenepropionic acid]oxytocin was prepared from beta-Mpa(beta-(CH2)5)(Bzl)-Tyr(Bzl)-Ile-Gln-Asn-Cys(Bzl)-Pro-Leu-Gly-NH2 by removal of the Bzl-protecting groups with Na-NH3 followed by cyclization of the resulting disulfhydryl compound with K3Fe(CN)6.The analog was purified by desalting on Sephadex G-15 in 50% HOAc and gel filtration on Sephadex G-25 and LH-20. The protected intermediate above was synthesized from Z-Cys(Bzl)-Pro-Leu-Gly-NH2 by the stepwose p-nitrophenyl ester method using Nalpha-Boc protection at the penta-, hexa-, and octapeptide stages. The analog was found to be a potent inhibitor of the oxytocic and avian vasodepressor effects of oxytocin (pA2 values of 7.43 and 8.30, respectively) but was only a weak inhibitor of the rat pressor effect of 8-lysine-vasopressin. The rat antipressor potency of [1-deaminopenicillamine]oxytocin was also determined in this study: pA2 = 6.27. Of the alkyl-substituted 1-position analogs of oxytocin studied so far, [1-beta-mercapto-beta,beta-pentamethylenepropionic acid]oxytocin is the most potent antioxytocic agent.


Assuntos
Ocitocina/análogos & derivados , Ocitocina/antagonistas & inibidores , Animais , Pressão Sanguínea/efeitos dos fármacos , Galinhas , Cromatografia em Camada Fina , Feminino , Masculino , Contração Muscular/efeitos dos fármacos , Ocitocina/síntese química , Ocitocina/farmacologia , Propionatos/síntese química , Propionatos/farmacologia , Ratos , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/farmacologia , Útero/efeitos dos fármacos
11.
Proc Natl Acad Sci U S A ; 69(11): 3322-6, 1972 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4508326

RESUMO

The peaks in the proton nuclear magnetic resonance spectrum of deamino-lysine-vasopressin in aqueous solution at pH values between 3 and 5 were assigned to particular amino-acid residues by use of the results of transfer-of-saturation studies, NH-C(alpha)H and C(alpha)H-C(beta)H decoupling experiments, and other data. The conformation of deamino-lysine-vasopressin in water differs from that of lysine-vasopressin in the same solvent.


Assuntos
Lisina , Espectroscopia de Ressonância Magnética , Vasopressinas , Sequência de Aminoácidos , Desaminação , Concentração de Íons de Hidrogênio , Conformação Proteica , Temperatura
12.
Proc Natl Acad Sci U S A ; 69(8): 2169-73, 1972 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4506086

RESUMO

The peaks in the proton NMR spectrum of lysine-vasopressin in aqueous solution at pH 3-5 were assigned to particular amino-acid residues by the use of the results of dilution studies and NH-C(alpha)H and C(alpha)H-C(beta)H decoupling experiments. The conformation of lysine-vasopressin in water differs from its conformation in dimethylsulfoxide.


Assuntos
Lisina , Espectroscopia de Ressonância Magnética , Conformação Proteica , Vasopressinas , Deutério , Dimetil Sulfóxido , Concentração de Íons de Hidrogênio , Soluções , Relação Estrutura-Atividade , Água
18.
Proc Natl Acad Sci U S A ; 68(12): 3088-91, 1971 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-5289251

RESUMO

The 220-MHz proton NMR spectra of lysine-vasopressin and some related compounds are examined in deuterated dimethyl sulfoxide to obtain structural information that must be satisfied by any proposed conformation of the molecule. This structural information is in the form of dihedral angles (for rotation about the NH-C(alpha)H bonds) from coupling constants, possible hydrogen bonding of the CONH(2) and backbone amide groups from the temperature-dependence of the chemical shift, and aromatic ring-aromatic ring interaction from the effect of the magnetically anisotropic groups on the chemical shift.


Assuntos
Lisina , Vasopressinas , Fenômenos Químicos , Química , Deutério , Raios Infravermelhos , Isomerismo , Espectroscopia de Ressonância Magnética , Peptídeos , Conformação Proteica , Análise Espectral , Temperatura
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