783300-35-6Relevant articles and documents
The kinetic resolution of oxazinones by alcoholysis: access to orthogonally protected β-amino acids
Cronin, Sarah A.,Connon, Stephen J.
supporting information, p. 7348 - 7352 (2021/09/07)
The catalytic, alcoholytic kinetic resolution of oxazinones is reported. A novel, stereochemically dense cinchona alkaloid-based catalyst can facilitate the highly enantiodiscriminatory (Sup to 101) ring-opening of oxazinones equipped with electrophilic aryl units to generate orthogonally protected β-amino acids for the first time.
Iridium-catalysed C-H borylation of β-aryl-aminopropionic acids
MacDonald, Simon J. F.,Nortcliffe, Andrew,Robinson, Henry,Simelis, Klemensas,Stillibrand, Joe
supporting information, p. 6696 - 6701 (2020/09/21)
Iridium-catalysed catalytic, regioselective C-H borylation of β-aryl-aminopropionic acid derivatives gives access to 3,5-functionalised protected β-aryl-aminopropionic acid boronates. The synthetic versatility of these new boronates is demonstrated through sequential one-pot functionalisation reactions to give diverse building blocks for medicinal chemistry. The C-H borylation is also effective for dipeptide substrates. We have exemplified this methodology in the synthesis of a pan αv integrin antagonist.
Characterization of a new nitrilase from Hoeflea phototrophica DFL-43 for a two-step one-pot synthesis of (S)-β-amino acids
Zhang, Zhi-Jun,Cai, Rui-Feng,Xu, Jian-He
, p. 6047 - 6056 (2018/05/15)
A nitrilase from Hoeflea phototrophica DFL-43 (HpN) demonstrating excellent catalytic activity towards benzoylacetonitrile was identified from a nitrilase tool-box, which was developed previously in our laboratory for (R)-o-chloromandelic acid synthesis from o-chloromandelonitrile. The HpN was overexpressed in Escherichia coli BL21 (DE3), purified to homogeneity by nickel column affinity chromatography, and its biochemical properties were studied. The HpN was very stable at 30–40?°C, and highly active over a wide range of pH values (pH 6.0–10.0). In addition, the HpN could tolerate against several hydrophilic organic solvents. Steady-state kinetics indicated that HpN was highly active towards benzoylacetonitrile, giving a KM of 4.2?mM and a kcat of 170?s?1, the latter of which is ca. fivefold higher than the highest record reported so far. A cascade reaction for the synthesis of optically pure (S)-β-phenylalanine from benzoylacetonitrile was developed by coupling HpN with an ω-transaminase from Polaromonas sp. JS666 in toluene-water biphasic reaction system using β-alanine as an amino donor. Various (S)-β-amino acids could be produced from benzoylacetonitrile derivatives with moderate to high conversions (73–99%) and excellent enantioselectivity (> 99% ee). These results are significantly advantageous over previous studies, indicating a great potential of this cascade reaction for the practical synthesis of (S)-β-phenylalanine in the future.
The bacterial ammonia lyase EncP: A tunable biocatalyst for the synthesis of unnatural amino acids
Weise, Nicholas J.,Parmeggiani, Fabio,Ahmed, Syed T.,Turner, Nicholas J.
supporting information, p. 12977 - 12983 (2015/10/28)
Enzymes of the class I lyase-like family catalyze the asymmetric addition of ammonia to arylacrylates, yielding high value amino acids as products. Recent examples include the use of phenylalanine ammonia lyases (PALs), either alone or as a gateway to deracemization cascades (giving (S)- or (R)-α-phenylalanine derivatives, respectively), and also eukaryotic phenylalanine aminomutases (PAMs) for the synthesis of the (R)-β-products. Herein, we present the investigation of another family member, EncP from Streptomyces maritimus, thereby expanding the biocatalytic toolbox and enabling the production of the missing (S)-β-isomer. EncP was found to convert a range of arylacrylates to a mixture of (S)-α- and (S)-β-arylalanines, with regioselectivity correlating to the strength of electron-withdrawing/-donating groups on the ring of each substrate. The low regioselectivity of the wild-type enzyme was addressed via structure-based rational design to generate three variants with altered preference for either α- or β-products. By examining various biocatalyst/substrate combinations, it was demonstrated that the amination pattern of the reaction could be tuned to achieve selectivities between 99:1 and 1:99 for β:α-product ratios as desired.
Carica papaya lipase catalysed resolution of β-amino esters for the highly enantioselective synthesis of (S)-dapoxetine
You, Pengyong,Qiu, Jian,Su, Erzheng,Wei, Dongzhi
, p. 557 - 565 (2013/03/13)
An efficient synthesis of the (S)-3-amino-3-phenylpropanoic acid enantiomer has been achieved by Carica papaya lipase (CPL) catalysed enantioselective alcoholysis of the corresponding racemic N-protected 2,2,2-trifluoroethyl esters in an organic solvent. A high enantioselectivity (E > 200) was achieved by two strategies that involved engineering of the substrates and optimization of the reaction conditions. Based on the resolution of a series of amino acids, it was found that the structure of the substrate has a profound effect on the CPL-catalysed resolution. The enantioselectivity and reaction rate were significantly enhanced by switching the conventional methyl ester to an activated trifluoroethyl ester. When considering steric effects, the substituted phenyl and amino groups should not both be large for the CPL-catalysed resolution. The mechanism of the CPL-catalysed enantioselective alcoholoysis of the amino acids is discussed to delineate the substrate requirements for CPL-catalysed resolution. Finally, the reaction was scaled up, and the products were separated and obtained in good yields (≥ 80 %). The (S)-3-amino-3- phenylpropanoic acid obtained was used as a key chiral intermediate in the synthesis of (S)-dapoxetine with very high enantiomeric excess (> 99 %). A carica papaya lipase catalysed resolution of N-protected β-phenylalanine esters has been developed. High enantioselectivity was achieved by two strategies that involved engineering of the substrates and optimization of the reaction conditions. After 50 % conversion, the products were separated and used as key chiral intermediates for the synthesis of (S)-dapoxetine with > 99 % ee. Copyright
Parallel synthesis of homochiral β-amino acids
Davies, Stephen G.,Mulvaney, Andrew W.,Russell, Angela J.,Smith, Andrew D.
, p. 1554 - 1566 (2008/02/09)
The parallel asymmetric synthesis of an array of 30 β-amino acids of high enantiomeric purity using the conjugate addition of homochiral lithium N-benzyl-N-(α-methylbenzyl)amide as the key step is accomplished. The experimental simplicity and highly practical nature of the protocol is demonstrated by the efficient parallel conversion of 15 α,β-unsaturated esters to both enantiomeric series of the corresponding β-amino acids in high overall yields and selectivities with minimal purification involved in each step of the reaction protocol.
β-phenylalanine derivatives as integrin antagonists
-
, (2008/06/13)
The present invention relates to compounds of the general formula (1) wherein R4 is —SO2R4, —COOR4′, —COR4′, —CONR4′2 or —CSNR4′2; R4′is hydrogen, a substituted or unsubstituted alkyl or cycloalkyl residue, a substituted or unsubstituted aryl residue or a saturated or unsaturated, optionally substituted heterocyclic residue; R4″is a substituted or unsubstituted alkyl or cycloalkyl residue, a substituted or unsubstituted aryl residue or a saturated or unsaturated, optionally substituted heterocyclic residue; L is a sulphonamide, amide, ether, ester, keto, urea, thioether, sulphoxide or sulphone unit optionally extended by one or two methylene groups; and X is N, O or S; and their physiologically acceptable salts and stereoisomers. The present invention furthermore relates to a process for the preparation of the compounds of the formula (1), a pharmaceutical composition containing at least one of these compounds, and the use of compounds of the formula (1) for the production of a pharmaceutical composition having integrin-antagonistic action and in particular for the therapy and prophylaxis of cancer, osteolytic diseases such as osteoporosis, arteriosclerosis, restenosis and ophthalmic disorders.
One-Pot Cyclization of Alkoxy-3-Aminoindan-1-ones.
Dallemagne, Patrick,Rault, Sylvain,Pilo, Juan Carlos,Foloppe, Marie Paule,Robba, Max
, p. 6327 - 6328 (2007/10/02)
3-Amino-3-alkoxyphenylpropionic acids, prepared from alkoxybenzaldehydes, are cyclized in one step into 3-aminoindan-1-ones using trifluoroacetic acid and trifluoroacetic anhydride. Key Words: One-pot cyclization; Aminoindanones; Electrodonating substitue
