In situ N-phosphorylation of oligopeptides for fast atom bombardment mass spectrometry
摘要:
AbstractPositive ion fast atom bombardment mass spectrometry (FABMS) of in situ N‐phosphorylated oligopeptides showed intense quasi‐molecular ions together with the successive alkene loss fragment ions, which afford multiple checks of the unequivocal reality of the relative molecular mass of the tested samples. More interesting, in a novel cleavage pattern only the N‐phosphoryl fragment ions gave intense peaks, the C‐terminal series ions being suppressed. For each of the N‐terminal ions, losses of alkenes also occur to provide multiple checks for the existence of these ions. The FABMS of the in situ N‐ phosphorylated oligopeptides might provide an easily accessible routine method for peptide sequencing.
amide-involved chelate(s) under acidic conditions. Reaction of H(L2) with [Co(tren)]3+ (tren = tris(2-aminoethyl)amine) revealed the exclusive coordination of (L2)−via its (O,O) chelate to the metal core while treatment of the Co-complex with Pd(II) resulted in the formation of a Co/Pd heterobimetallic complex in solution with (NH2, Namide) chelated Pd(II). Reaction of 3 with 9-methylguanine indicated the N7
hydroxamic acids, Ala-Ala-NHOH, Ala-Ala-N(Me)OH, Ala-Gly-Gly-NHOH and Ala-Gly-Gly-N(Me)OH were synthesized and their interaction with Pd(II) (as a Pt(II) model but with faster ligand exchange reactions) was studied in aqueous solution in the presence of the Cl− competitor ion by pH-potentiometric and 1H NMR methods. To the best of our knowledge, this is the first detailed solution study on Pd(II)–peptide
合成了伯,仲二肽和三肽异羟肟酸Ala-Ala-NHOH,Ala-Ala-N(Me)OH,Ala-Gly-Gly-NHOH和Ala-Gly-Gly-N(Me)OH用Pd(II)(作为铂(II)的模式,但以更快的配体交换反应)中的溶液中在CL的存在水溶液研究-通过pH-电位和竞争者离子1种1 H NMR方法。据我们所知,这是对Pd(II)-肽异羟肟酸酯系统的第一个详细溶液研究,结果表明,除Ala-Gly-Gly-NHOH外,其他三个配体不仅充当配位化合物,而且还充当配位体的水解并形成质子化的羟胺和Pd(II)在酸性条件下出现了相应肽的复合物。使用Ala-Gly-Gly-N(Me)OH的水解相当慢(超过一个星期),而使用Ala-Ala-NHOH的水解则快一点,因此也可以在含有以下一种的系统上成功进行形态研究后两个配体。但是,这对于Pd(II)–Ala-Ala-N(Me)OH体系是不利的,在该体系
Kalikhevich, V. N.; Churkina, S. I.; Martynov, V. F., Journal of general chemistry of the USSR, 1981, vol. 51, p. 1690 - 1695
作者:Kalikhevich, V. N.、Churkina, S. I.、Martynov, V. F.
DOI:——
日期:——
(Cyanomethylene)phosphoranes as Novel Carbonyl 1,1-Dipole Synthons: An Efficient Synthesis of .alpha.-Keto Acids, Esters, and Amides
作者:Harry H. Wasserman、Wen-Bin Ho
DOI:10.1021/jo00095a005
日期:1994.8
Carboxylic acids react with (cyanomethylene)triphenylphosphorane in the presence of EDCI to form cyano keto phosphoranes. The resulting ylides may then be oxidatively cleaved with ozone to form alpha,beta-diketonitriles. These highly electrophilic products may then be converted in situ to alpha-keto acids, esters, and amides.
3-hydroxypropionitrile: A new reagent for carboxyl protection in peptide synthesis