35593-57-8Relevant academic research and scientific papers
A practical method for the combinatorial synthesis of peptide aldehydes
Hall, Beverley J.,Sutherland, John D.
, p. 6593 - 6596 (1998)
A practical strategy for solid phase synthesis of peptide aldehydes is described. An olefin linker is constructed using Wittig chemistry, after peptide synthesis ozonolytic treatment of the linker and subsequent workup with dimethyl sulphide results in fa
Probing α-Amino Aldehydes as Weakly Acidic Pronucleophiles: Direct Access to Quaternary α-Amino Aldehydes by an Enantioselective Michael Addition Catalyzed by Br?nsted Bases
García-Urricelqui, Ane,de Cózar, Abel,Mielgo, Antonia,Palomo, Claudio
supporting information, p. 2483 - 2492 (2020/12/25)
The high tendency of α-amino aldehydes to undergo 1,2-additions and their relatively low stability under basic conditions have largely prevented their use as pronucleophiles in the realm of asymmetric catalysis, particularly for the production of quaternary α-amino aldehydes. Herein, it is demonstrated that the chemistry of α-amino aldehydes may be expanded beyond these limits by documenting the first direct α-alkylation of α-branched α-amino aldehydes with nitroolefins. The reaction produces densely functionalized products bearing up to two, quaternary and tertiary, vicinal stereocenters with high diastereo- and enantioselectivity. DFT modeling leads to the proposal that intramolecular hydrogen bonding between the NH group and the carbonyl oxygen atom in the starting α-amino aldehyde is key for reaction stereocontrol.
Asperphenamate biosynthesis reveals a novel two-module NRPS system to synthesize amino acid esters in fungi
Li, Wei,Fan, Aili,Wang, Long,Zhang, Peng,Liu, Zhiguo,An, Zhiqiang,Yin, Wen-Bing
, p. 2589 - 2594 (2018/03/08)
Amino acid esters are a group of structurally diverse natural products with distinct activities. Some are synthesized through an inter-molecular esterification step catalysed by nonribosomal peptide synthetase (NRPS). In bacteria, the formation of the intra-molecular ester bond is usually catalysed by a thioesterase domain of NRPS. However, the mechanism by which fungal NRPSs perform this process remains unclear. Herein, by targeted gene disruption in Penicillium brevicompactum and heterologous expression in Aspergillus nidulans, we show that two NRPSs, ApmA and ApmB, are sufficient for the synthesis of an amino acid ester, asperphenamate. Using the heterologous expression system, we identified that ApmA, with a reductase domain, rarely generates dipeptidyl alcohol. In contrast, ApmB was determined to not only catalyse inter-molecular ester bond formation but also accept the linear dipeptidyl precursor into the NRPS chain. The mechanism described here provides an approach for the synthesis of new small molecules with NRPS as the catalyst. Our study reveals for the first time a two-module NRPS system for the formation of amino acid esters in nature.
Asymmetric hydroformylation of Z -Enamides and enol esters with rhodium-bisdiazaphos catalysts
Abrams, M. Leigh,Foarta, Floriana,Landis, Clark R.
supporting information, p. 14583 - 14588 (2015/01/08)
Asymmetric hydroformylation (AHF) of Z-enamides and Z-enol esters provides chiral, alpha-functionalized aldehydes with high selectivity and atom economy. Rh-bisdiazaphospholane catalysts enable hydroformylation of these challenging disubstituted substrates under mild reaction conditions and low catalyst loadings. The synthesis of a protected analog of l-DOPA demonstrates the utility of AHF for enantioselective, atom-efficient synthesis of peptide precursors.
Organocatalytic asymmetric biomimetic transamination of α-keto acetals to chiral α-amino acetals
Pan, Hongjie,Xie, Ying,Liu, Mao,Shi, Yian
, p. 2389 - 2392 (2014/01/06)
This paper describes a chiral base-catalyzed asymmetric biomimetic transamination of α-keto acetals. A wide variety of α-amino acetals containing various functional groups can be synthesized in 50-85% yield and 82-86% ee.
Stereoselective intramolecular cyclization of isopentenyl benzamide via π-allylpalladium complex catalyzed by Pd(0)
Joo, Jae-Eun,Mu, Yu,Lee, Yiu-Suk,Tian, Yong-Shou,Lee, Gyu-Jin,Ham, Won-Hun
experimental part, p. 293 - 304 (2010/08/20)
An efficient procedure was developed to synthesize oxazoline as key intermediate in the total synthesis of (+)-lactacystin using palladium(0)-catalyzed intramolecular cyclization of isopentenyl benzamide via a π-allylpalladium complex. A convenient and ef
Tandem palladium-catalyzed allene arylation and oxazoline formation
Cook, Gregory R.,Xu, Wei
, p. 215 - 232 (2007/10/03)
The tandem palladium-catalyzed addition of aryl iodides to allenes followed by cyclization to afford oxazolines was investigated. A variety of chiral 5-vinyloxazolines were obtained in high yield with excellent stereoselectivity via equilibration of the i
Discovery of phenyl alanine derived ketoamides carrying benzoyl residues as novel calpain inhibitors
Lubisch, Wilfried,Moeller
, p. 1335 - 1338 (2007/10/03)
Novel calpain inhibitors derived from phenyl alanine aldehydes or ketoamides carrying a benzoyl residue were prepared and evaluated for their biological potency. A brief structure-activity relationship elucidated the importance of ortho-substitutents in t
Facile and efficient total synthesis of (+)-preussin.
Lee,Kim,Oh,Ham
, p. 4041 - 4042 (2007/10/03)
[structure] The enantioselective total synthesis of (+)-preussin, a potent antifungal agent, has been achieved. The key steps are a Pd(0)-catalyzed oxazoline-forming reaction from L-phenylalanine, hydrogenolysis, and subsequent diastereoselective reductive cyclization of the intermediate aminoketone to pyrrolidine using Pearlman's catalyst.
Stereoselective intramolecular cyclization of allyl and homoallyl benzamide via π-allylpalladium complex catalyzed by Pd(0)
Lee, Kee-Young,Kim, Yong-Hyun,Park, Min-Sung,Oh, Chang-Young,Ham, Won-Hun
, p. 9450 - 9458 (2007/10/03)
The transformation of acyclic allylic benzamides 4 and homoallylic benzamides 12 to vinyl oxazolines 3 is achieved in the presence of base by the catalysis and Pd(0) in high yield and with high diastereoselectivity. Especially, in the case of homoallylic benzamides 12, trans-oxazolines 3 are formed exclusively or predominantly over cis-oxazolines 8, irrespective of the composition of their stereoisomers. The reaction is believed to proceed via the same π-allylpalladium complex that arises from either primary or secondary allylic acetates. We applied this method to the syntheses of β- amino-α-hydroxy acids 1 and γ-amino-β-hydroxy acids 2, conveniently protected as oxazoline.
