72150-35-7Relevant academic research and scientific papers
Identification of 1,5,7-Triazabicyclododecene and Polystyrene-Supported Superbases as Efficient Hydroxylaminolysis Agents of Sterically Hindered and Epimerizable Esters
Pierre, Romain,Gaigne, Frédéric,El-Bazbouz, Ghizlane,Mouis, Grégoire,Ouvry, Gilles,Tomas, Loic,Harris, Craig S.
supporting information, p. 1102 - 1106 (2018/04/24)
In modern pharmaceutical research, the need for reliable protocols for the preparation of chemical libraries in a controlled manner is quintessential to driving the Design-Make-Test cycle in drug discovery programs. In this letter, we communicate the iden
Novel diphenylmethyl-derived amide protecting group for efficient liquid-phase peptide synthesis: AJIPHASE
Takahashi, Daisuke,Yano, Tatsuya,Fukui, Tatsuya
supporting information, p. 4514 - 4517 (2012/10/29)
An efficient method for the synthesis of peptides bearing an amide at the C-terminal is described. This method involves the attachment of a C-terminal protecting group bearing long aliphatic chains, followed by the repetition of simple reaction and precipitation steps with the combined advantages of liquid-phase peptide synthesis (LPPS) and solid-phase peptide synthesis (SPPS). Using this method, a hydrophobic peptide was successfully synthesized in good yield and high purity, which cannot be obtained satisfactorily by SPPS.
Protein backbone modification by novel C(α)-C side-chain scission
Ranganathan,Vaish,Shah
, p. 6545 - 6557 (2007/10/02)
α-Ketoamide (-NH-CO-CO-) units in intact peptides are generated from Ser/Thr residues via Ru(VIII)-catalyzed C(α)-C side-chain scission. Facets associated with this novel α-carbon modification have been probed with 75 peptides chosen to represent every possible peptide environment. The reactions were carried out at room temperature with in situ generated Ru(VIII) in biphasic (CH3CN/CCl4/pH 3 phosphate buffer, 1:1:2 v/v) medium. Whereas Ser/Thr residues placed at the C-terminal end in peptides undergo N-C bond scission leading to des-Ser/Thr peptide amides - thus acting as Gly equivalents in simulating the α-amidating action of pituitary enzymes - those located at the N-terminal or nonterminal or even at the C-terminal position (protected as amide) were found to undergo oxidative C-C bond scission (involving C(α) and C side-chain bond), resulting in the generation of α-ketoamide (-NH-CO-CO-) units in the intact peptide backbone. The difference in the products arising from C(α)-C side-chain scission of Ser/Thr esters and amides is rationalized on the basis of a common mechanism involving either oxaloesters [PeP-NH-CO-COX; X = OMe] or oxalamides [X = NH2 or NH-Pep] arising from the oxidation of initially formed carbinolamide intermediates [Pep-NH-CH(OH)-COX], wherein, while the former are shown to undergo hydrolysis to terminal amides [Pep-NH2], the oxalamides are found to be stable to hydrolysis. Ancillary noteworthy findings are those of peptide bond scission when contiguous Ser-Ser/Thr-Thr residues are present and the oxidative cleavage at C-terminal Tyr/Trp sites generating des amides. The oxidative methodology presented here is mild, simple, and practical and proceeds with chiral retention. The insensitivity of a large number of amino acid residues, such as Gly, Ala, Leu, Asn, Gln, Asp, Glu, Pro, Arg, Phe, Lys, Val, and Aib, and N-protecting groups, such as Boc, Z, and Bz, toward Ru(VIII) under the experimental conditions should make this methodology practical and useful. Sulfur-containing amino acids Cys and Met get oxidized to sulfones in the products.
Asymmetric Hydrogenation with Chiral Aminophosphine-Rhodium Complexes and Chiral Recognition by Bisphosphine-Rhodium Complexes in the Asymmetric Hydrogenation of Olefins through the Chiral Helical Conformation of Phenyl Groups on the Phosphorus Atom
Onuma, Ken-ichi,Ito, Tomiyasu,Nakamura, Asao
, p. 2016 - 2019 (2007/10/02)
The asymmetric hydrogenation of α-acylaminocinnamic acids with the rhodium complex of (1R,2R)-1,2-bis(N-diphenylphosphino-N-methylamino)cyclohexane has been reported to give preferentially (S)-amino acids.On the contrary, it has been found that the enanti
