Total synthesis of bovine pancreatic ribonuclease A. Part 2. Synthesis of the protected hexatriacontapeptide ester (positions 89–124)
作者:Nobutaka Fujii、Haruaki Yajima
DOI:10.1039/p19810000797
日期:——
Commencing with the protected C-terminal pentadecapeptide of bovinepancreatic RNase,Z(OMe)-(RNase 110–124)-OBzl, chain elongation was accomplished to form the hexatriacontapeptide, Z(OMe)-(RNase 89–124)-OBzl, by six successive azide condensations of the peptide fragments, Z(OMe)-Val-Ala-NHNH2(4), Z(OMe)-Ile-Ile-NHNH2(5), Z(OMe)-Asn-Lys(Z)-His-NHNH2(6), Z(OMe)-Lys(Z)-Thr-Thr-Gln-Ala-NHNH2(7), Z(OM
Solution-Phase Synthesis of an Anti-human Immunodeficiency Virus Peptide, T22 ((Tyr5,12, Lys7)-Polyphemusin II), and the Modification of Trp by the p-Methoxybenzyl Group of Cys during Trimethylsilyl Trifluoromethanesulfonate Deprotection.
was found to have a strong anti-human immunodeficiency virus (HIV) activity, comparable to that of 3'-azido-2',3'-dideoxy-thymidine (AZT). In the present study, the solution-phase synthesis of T22 was attempted in order to produce this peptide on a large scale. An 18-residue peptide amide corresponding to the entire aminoacid sequence of T22 was synthesized by assembling four peptide fragments and
The properties of S-benzyloxymethylcysteine, Cys(Bom), were examined. The S-Bom group is stable to trifluoroacetic acid (TFA), but is easily cleaved by treatment with silver trifluoromethanesulfonate (AgOTl)/TFA or 1 M trimethylsilyl trifluoromethanesulfonate (TMSOTf)-thioanisole/TFA. Cys(Bom) can be converted to cystine by treatment with thallium(III) trifluoroacetate.Cys(Bom)was successfully applied to the Fmoc-based solid phase synthesis of porcine brain natriuretic peptide (pBNP), a 26-residue peptide with one disulfide bond [Fmoc=9-fluorenylmethyloxycarbonyl]. In the final step, the peptide-resin was first treated with AgOTl/TFA, then with 1 M trimethyisllyl bromide-thioanisole/TFA. After dithiothreitol treatment and subsequent air-oxidation, a homogeneous pBNP was obtained in 17% yiled, based on the first amino acid loaded on the resin. The results was compared with those produced by other alternative deprotecting procedures.
α-Human atrial natriuretic peptide (α-hANP) was synthesized by assembling six peptide fragments in solution followed by deprotection with HF and subsequent air-oxidation. The trimethylbenzyl group was employed as an S-protecting group of cysteine. The HF-dimethylselenide-m-cresol system was employed as a final deprotecting reagent and, at the same time, as a reducing reagent of Met(O). Syntheric α-hANP elicited potent diuretic and natriuretic activity in rats.
α-人心房利钠肽(α-hANP)是通过在溶液中组装六个肽片段,然后用氢氟酸脱保护并随后进行空气氧化合成的。三甲基苄基被用作半胱氨酸的 S 保护基团。氢氟酸-二甲基硒-间甲酚体系被用作最终的脱保护试剂,同时也是 Met(O) 的还原试剂。合成的 α-hANP 对大鼠具有强效的利尿和利钠活性。
Acceleration of the N.ALPHA.-Deprotection Rate by the Addition of m-Cresol to Diluted Methanesulfonic Acid and Its Application to the Z(OMe)-Based Solid-Phase Syntheses of Human Pancreastatin-29 and Magainin 1.
In solid-phasepeptide synthesis, the addition of m-cresol to diluted methanesulfonic acid (MSA) in dichloromethane accelerated the deprotection rate of the acid-labile alpha-amino protecting group, the p-methoxybenzyloxycarbonyl (Z(OMe)) group. Further, 0.1 M MSA, 20% m-cresol/CH2Cl2 was found to be a practically useful N alpha-deprotecting reagent system, since the deprotection of the Z(OMe) group
在固相肽合成中,将间甲酚添加到二氯甲烷中的稀释甲磺酸(MSA)中可加快酸不稳定的α-氨基保护基对甲氧基苄氧基羰基(Z(OMe))的脱保护速度。此外,发现0.1 M MSA,20%间甲酚/ CH2Cl2是一种实用的Nα-脱保护试剂体系,因为Z(OMe)基团的脱保护在室温下30分钟内有选择地发生,而另一个保持完整侧链保护基,例如苄氧基羰基,苄基酯,Sp-甲氧基苄基和NG-均三甲苯基-2-磺酰基。该试剂体系应用于人胰泌素29和magainin 1的基于Z(OMe)的固相合成。