59859-77-7Relevant academic research and scientific papers
Gold-Catalyzed Amide/Carbamate-Linked N, O-Acetal Formation with Bulky Amides and Alcohols
Ohsawa, Kosuke,Ochiai, Shota,Kubota, Junya,Doi, Takayuki
, p. 1281 - 1291 (2021/01/14)
A gold-catalyzed N,O-acetal formation was established to construct an amide/carbamate-linked N,O-acetal substructure with bulky alcohols. The acyliminium cation species generated from o-alkynylbenzoic acid ester in the presence of a gold catalyst is highly reactive and underwent nucleophilic attack of various bulky alcohols and phenols at room temperature under neutral conditions, leading to the corresponding N,O-acetals in yields of 34-89% with good functional group tolerance.
Total Synthesis and Antimycobacterial Activity of Ohmyungsamycin A, Deoxyecumicin, and Ecumicin
Hawkins, Paige M. E.,Tran, Wendy,Nagalingam, Gayathri,Cheung, Chen-Yi,Giltrap, Andrew M.,Cook, Gregory M.,Britton, Warwick J.,Payne, Richard J.
supporting information, p. 15200 - 15205 (2020/10/23)
The ohmyungsamycin and ecumicin natural product families are structurally related cyclic depsipeptides that display potent antimycobacterial activity. Herein the total syntheses of ohmyungsamycin A, deoxyecumicin, and ecumicin are reported, together with the direct biological comparison of members of these natural product families against Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB). The synthesis of each of the natural products employed a solid-phase strategy to assemble the linear peptide precursor, involving a key on-resin esterification and an optional on-resin dimethylation step, before a final solution-phase macrolactamization between the non-proteinogenic N-methyl-4-methoxy-l-tryptophan amino acid and a bulky N-methyl-l-valine residue. The synthetic natural products possessed potent antimycobacterial activity against Mtb with MIC90’s ranging from 110–360 nm and retained activity against Mtb in Mtb-infected macrophages. Deoxyecumicin also exhibited rapid bactericidal killing against Mtb, sterilizing cultures after 21 days.
Total Synthesis of Ecumicin
Hawkins, Paige M. E.,Giltrap, Andrew M.,Nagalingam, Gayathri,Britton, Warwick J.,Payne, Richard J.
supporting information, p. 1019 - 1022 (2018/02/23)
The first total synthesis of the potent anti-mycobacterial cyclic depsipeptide natural product ecumicin is described. Synthesis was achieved via a solid-phase strategy, incorporating the synthetic non-proteinogenic amino acids N-methyl-4-methoxy-l-tryptophan and threo-β-hydroxy-l-phenylalanine into the growing linear peptide chain. The synthesis employed key on-resin esterification and dimethylation steps as well as a final macrolactamization between the unusual N-methyl-4-methoxy-l-tryptophan unit and a bulky N-methyl-l-valine residue. The synthetic natural product possessed potent antimycobacterial activity against the virulent H37Rv strain of Mycobacterium tuberculosis (MIC90 = 312 nM).
ANTHELMINTIC DEPSIPEPTIDE COMPOUNDS
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Page/Page column 233, (2018/06/06)
The present invention provides cyclic depsipeptide compounds of formula (I) wherein the stereochemical configuration of at least one carbon atom bearing the groups Cy1, Cy2, R1, R2, R3, R4, Ra and Rb is inverted compared with the naturally occurring cyclic depsipeptide PF1022A. The invention also provides compositions comprising the compounds that are effective against parasites that harm animals. The compounds and compositions may be used for combating parasites in or on mammals and birds. The invention also provides for an improved method for eradicating, controlling and preventing parasite infestation in birds and mammals.
Optimized syntheses of Fmoc azido amino acids for the preparation of azidopeptides
Pícha, Jan,Budě?ínsky, Milo?,Machá?ková, Kate?ina,Collinsová, Michaela,Jirá?ek, Ji?í
, p. 202 - 214 (2017/04/06)
The rise of CuI-catalyzed click chemistry has initiated an increased demand for azido and alkyne derivatives of amino acid as precursors for the synthesis of clicked peptides. However, the use of azido and alkyne amino acids in peptide chemistry is complicated by their high cost. For this reason, we investigated the possibility of the in-house preparation of a set of five Fmoc azido amino acids: β-azido l-alanine and d-alanine, γ-azido l-homoalanine, δ-azido l-ornithine and ω-azido l-lysine. We investigated several reaction pathways described in the literature, suggested several improvements and proposed several alternative routes for the synthesis of these compounds in high purity. Here, we demonstrate that multigram quantities of these Fmoc azido amino acids can be prepared within a week or two and at user-friendly costs. We also incorporated these azido amino acids into several model tripeptides, and we observed the formation of a new elimination product of the azido moiety upon conditions of prolonged couplings with 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate/DIPEA. We hope that our detailed synthetic protocols will inspire some peptide chemists to prepare these Fmoc azido acids in their laboratories and will assist them in avoiding the too extensive costs of azidopeptide syntheses. Experimental procedures and/or analytical data for compounds 3–5, 20, 25, 26, 30 and 43–47 are provided in the supporting information.
ANTHELMINTIC DEPSIPEPTIDE COMPOUNDS
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Page/Page column 214; 215, (2016/12/07)
The present invention provides cyclic depsipeptide compounds of formula (I) and compositions comprising the compounds that are effective against parasites that harm animals. The compounds and compositions may be used for combating parasites in or on mammals and birds. The invention also provides for an improved method for eradicating, controlling and preventing parasite infestation in birds and mammals.
Versatile selective α-carboxylic acid esterification of N-protected amino acids and peptides by alcalase
Nuijens, Timo,Cusan, Claudia,Kruijtzer, John A. W.,Rijkers, Dirk T. S.,Liskamp, Rob M. J.,Quaedflieg, Peter J. L. M.
experimental part, p. 809 - 814 (2009/07/11)
Under continuous removal of water, the industrial protease Alcalase allows selective synthesis of α-carboxylic acid methyl, ethyl, benzyl, allyl, 2-(trimethylsilyl)ethyl, and tert-butyl esters of amino acids and peptides under mild conditions in very high
Chemical investigations in the synthesis of O-serinyl aminoribosides
Ginisty, Maryon,Gravier-Pelletier, Christine,Le Merrer, Yves
, p. 142 - 150 (2007/10/03)
Glycosylation involving d-ribose derivatives and various N-protected tert-butyl l-serinates can be achieved efficiently by careful choice of the activation method at the anomeric position and of the Lewis acid promoter. The conditions described allow the major formation of the β-anomer required for further elaboration to liposidomycin and caprazamycin analogues.
A short and efficient synthesis of L-5,5,5,5',5',5'-hexafluoroleucine from N-Cbz-L-serine.
Anderson, James T,Toogood, Peter L,Marsh, E Neil G
, p. 4281 - 4283 (2007/10/03)
[reaction: see text] 5,5,5,5',5',5'-Hexafluoroleucine (6), a fluorous analogue of leucine, is of considerable interest as a building block in the design of fluorous proteins and peptides. We report a short and efficient synthesis of 6, which is obtained f
