140422-46-4Relevant academic research and scientific papers
An improved procedure for the synthesis of dehydroamino acids and dehydropeptides from the carbonate derivatives of serine and threonine using tetrabutylammonium fluoride
Ramapanicker, Ramesh,Mishra, Roli,Chandrasekaran, Srinivasan
, p. 123 - 125 (2010)
Dehydroamino acids are important precursors for the synthesis of a number of unnatural amino acids and are structural components in many biologically active peptide derivatives. However, efficient synthetic procedures for their production in large amounts
Silver-Promoted Direct Phosphorylation of Bulky C(sp2)-H Bond to Build Fully Substituted β-Phosphonodehydroamino Acids
Cao, Hao-Qiang,Liu, Hao-Nan,Liu, Zhe-Yuan,Qiao, Baokun,Zhang, Fa-Guang,Ma, Jun-An
, p. 6414 - 6419 (2020/09/02)
A general and practical cross-dehydrogenative coupling protocol between readily available trisubstituted α,β-dehydro α-amino carboxylic esters and H-phosphites is described. This C(sp2)-H phosphorylation reaction proceeds with absolute Z-selectivity promoted by silver salt in a radical relay manner. The bulky tetrasubstituted β-phosphonodehydroamino acids were obtained in grams and added new modules to the toolkit for peptide modifications.
An efficient synthesis of dehydroamino acids and dehydropeptides from O-Cbz and O-Eoc derivatives of serine and threonine
Ramesh, Ramapanicker,De, Kavita,Chandrasekaran, Srinivasan
, p. 10534 - 10542 (2008/02/13)
A simple and efficient method for the synthesis of dehydroamino acids from serine and threonine is reported. Various O-Cbz and O-Eoc derivatives of serine and threonine are prepared using CbzCl and EocCl, respectively, and are subjected to an anti-selective elimination on treatment with K2CO3 in DMF at 65 °C to afford dehydroalanine and dehydroamino butyric acid derivatives, respectively, in excellent yields. The high stability of these carbonate derivatives of serine and threonine allows their use in normal peptide synthesis as protected serine and threonine residues. Peptides synthesized by incorporating O-Cbz or O-Eoc derivatives undergo ready elimination under the reported conditions, to give the corresponding dehydropeptides in excellent yields. The reaction conditions are mild enough not to cause the racemization of other stereogenic centers present in the peptide.
A detailed investigation of the preparation of 2,7-diaminosuberic acid and 2,5-diaminoadipic acid derivatives using Kolbe electrolysis
Hiebl, Johann,Blanka, Michael,Guttman, Andras,Kollmann, Hermann,Leitner, Kornelia,Mayrhofer, Guenter,Rovenszky, Franz,Winkler, Karin
, p. 2059 - 2074 (2007/10/03)
The yield of protected 2,7-diaminosuberic acid (DAS) prepared by Kolbe reaction of N-protected α-glutamic acid esters is dependent on solvent, temperature, concentration of carboxylate onion, and protecting groups. The highest yield of protected L,L-2,7-diaminosuberic acid is obtained with Boc-Glu-OMe as starting material using MeOH/pyridine/NaOMe as electrolyte.
Aspects of the Palladium-Catalyzed Coupling between Aryl Halides and 2-Amidoacrylates
Carlstroem, Anne-Sofie,Frejd, Torbjoern
, p. 163 - 171 (2007/10/02)
The effect of using different salts, bases, catalysts and solvents as well as protecting froups in 2-amidoacrylate derivatives (olefin component) in the Heck coupling with iodobenzene has been studied.Salt effects, resulting in increased yields, were observed in combination with either NaHCO3 or triethylamine as the base.Pd(OAc)2, PdCl2, Pd/C and hydrogen-activated Pd black could all be used as catalyst with similar results.The best solvents were DMF or acetonitrile.Olefins 1a and 1c, both carrying orthogonal protecting groups, show the most potential for further app lications in peptide synthesis. 1,2-Diodobenzene and 1,8-diiodonaphthalene did not given any coupling products and 1-bromo-2-iodobenzene gave only mono-coupling in modest yield.In fact, small amounts of either 1,2-diiodobenzene or 1,8-diiodinaphthalene inhibited the coupling in other, normally reactive, cases.In experiments stoichiometric in Pd(OAc)2 it was found that an indolecarboxylic acid derivative was formed from iodobenzene, 2-bromoiodobenzene and 1,2-diiodobenzene, suggesting that ortho-palladation of a phenyl didehydroalanine derivative is involved.
