Synthesis of Casein-Related Peptides and Phosphopeptides. I. Solution-Phase Synthesis and 13C N.M.R.-Spectroscopy of the N-α-Acetyl Octapeptide N-Methylamide Corresponding to Region 14-21 of Bovine β-Casein A2

1987 ◽  
Vol 40 (2) ◽  
pp. 257 ◽  
Author(s):  
JW Perich ◽  
PF Alewood ◽  
RB Johns

The octapeptide, Ac-Glu-Ser-Leu-Ser-Ser-Ser-Glu-Glu-NHMe (I), was synthesized by the solution-phase method by using the mixed anhydride coupling procedure for the fragment condensation of the Nα-acetyl tripeptide, Ac-Glu(OBut)-Ser(But)-Leu-OH, with the pentapeptide N-methylamide hydrochloride, Cl.H2-Ser(But)-Ser(But)-Ser(But)-Glu(OBzl)-Glu(OBzl)-NHMe, followed by palladium-catalysed hydrogenolysis of Ac-Glu(OBut)-Ser(But)-Leu-Ser(But)-Ser(But)- Ser(But) Glu(OBzl)Glu(OBzl NHMe in trifluoroacetic acid. The synthesis of the two peptide fragments was accomplished in high yields and purity by using the repetitive excess mixed anhydride procedure and the isobutoxycarbonyl mixed anhydride of acetic acid for the rapid and high yielding N-acetylation of the tripeptide fragment. 13C n.m.r. spectroscopy was routinely used to monitor the efficiency of the coupling steps and to confirm the structure of octapeptide (1), signal assignments being possible for both the protected tri- and penta-peptides.

2016 ◽  
Vol 52 (17) ◽  
pp. 3497-3499 ◽  
Author(s):  
Miles A. White ◽  
Michelle J. Thompson ◽  
Gordon J. Miller ◽  
Javier Vela

Nanocrystalline LiZnP was synthesized using a flexible low temperature solution phase method that is generally applicable to other Nowotny–Juza phases.


2014 ◽  
Vol 10 ◽  
pp. 2279-2285 ◽  
Author(s):  
Alejandro Gimenez Molina ◽  
Amit M Jabgunde ◽  
Pasi Virta ◽  
Harri Lönnberg

An effective method for the synthesis of short oligoribonucleotides in solution has been elaborated. Novel 2'-O-(2-cyanoethyl)-5'-O-(1-methoxy-1-methylethyl) protected ribonucleoside 3'-phosphoramidites have been prepared and their usefulness as building blocks in RNA synthesis on a soluble support has been demonstrated. As a proof of concept, a pentameric oligoribonucleotide, 3'-UUGCA-5', has been prepared on a precipitative tetrapodal tetrakis(4-azidomethylphenyl)pentaerythritol support. The 3'-terminal nucleoside was coupled to the support as a 3'-O-(4-pentynoyl) derivative by Cu(I) promoted 1,3-dipolar cycloaddition. Couplings were carried out with 1.5 equiv of the building block. In each coupling cycle, the small molecular reagents and byproducts were removed by two quantitative precipitations from MeOH, one after oxidation and the second after the 5'-deprotection. After completion of the chain assembly, treatment with triethylamine, ammonia and TBAF released the pentamer in high yields.


2016 ◽  
Vol 14 (6) ◽  
pp. 2090-2111 ◽  
Author(s):  
Kozo Hattori ◽  
Kota Koike ◽  
Kensuke Okuda ◽  
Tasuku Hirayama ◽  
Masahiro Ebihara ◽  
...  

We have accomplished preparative solution-phase total syntheses of triostin A (17.5% in 13 steps) and its analogues with high yields to demonstrate their significant inhibitory activities on HIF-1 activation and cell proliferation.


1994 ◽  
Vol 351 ◽  
Author(s):  
Shreyas S. Kher ◽  
Richard L. Wells

ABSTRACTNanocrystalline materials have been intensely investigated in the recent past due to the novel properties associated with size-quantized particles. We have developed a new method for high yield, solution phase synthesis of nanocrystalline III-V semiconductors which eliminates the use of substituted or unsubstituted Group V hydrides and Group III alkyls. Our approach consists of in situ syntheses of (Na/K)3E (E = P, As, Sb) in aromatic solvents and subsequent reactions of these pnictides with Group III halide solutions in coordinating solvents. The nanocrystalline III-V semiconductors GaP, GaAs, GaSb, InP, InAs and InSb are readily prepared in a wide range of particle sizes (4–36 nm) and in high yields. The resultant Ill-V materials have been characterized by XRD, EDXA, TEM and elemental analyses.


1992 ◽  
Vol 45 (5) ◽  
pp. 919
Author(s):  
JW Perich ◽  
RM Valerio ◽  
RB Johns

This paper describes the synthesis of the 2-amino-4-(phosphono)butanoyl-containing peptide H-Glu-Abu(P)-Leu-OH.CF3CO2H by the use of Z-Abu(PO3Et2)-OH for the solution phase synthesis of Boc-Glu(Obut)-Abu(PO3Et2)-Leu-Obut (mixed-anhydride method) followed by acidolytic cleavage of the t-butyl groups, and final removal of the ethyl groups from Glu- Abu(PO3Et2)-Leu by treatment with 10% bromotrimethylsilane in acetonitrile. Although silylitic cleavage of the peptide was facile, the slow dissolution of the peptide in the reaction solvent suggests that deprotection of the Abu(PO3.Et2) residue has not yet been optimized.


Author(s):  
François Morvan ◽  
Aude-Emmanuelle Navarro ◽  
Cécile Dueymes ◽  
Ilaria Adamo ◽  
Andreas Schoenberger ◽  
...  

ChemInform ◽  
2010 ◽  
Vol 33 (35) ◽  
pp. 123-123
Author(s):  
Young K. Yun ◽  
John A. Porco Jr. ◽  
Jeff Labadie

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