- Preparation method of 3-aminopropanol or 3-aminopropionic acid derivative
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The invention provides a preparation method of an optically active 3-aminopropanol or 3-aminopropionic acid derivative, and belongs to the technical field of organic synthesis. A compound having a structure as shown in a formula II and a formula III is used as a raw material, and the optically active 3-aminopropanol or 3-aminopropionic acid derivative is obtained through four basic steps, namely dehydration condensation, hydrogenation reduction, reduction and hydrolysis. The raw materials adopted in the preparation method are easy to obtain and low in cost; as a chiral phosphine-transitional metal catalyst is used in the hydrogenation reduction reaction, the optically active 3-aminopropanol or 3-aminopropionic acid derivative is efficient, high in selectivity, low in cost and suitable forlarge-scale production. Compared with existing chemical resolution and chiral introduction, the asymmetric hydrogenation synthesis method provided by the invention only produces one chiral product, ishigh in yield, and has relatively high advantages in economy and raw material utilization rate.
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Paragraph 0229; 0241; 0242; 0245
(2018/10/11)
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- Improved enzymatic syntheses of valuable β-arylalkyl-β-amino acid enantiomers
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The enantioselective (E～ 200) Burkholderia cepacia-catalysed hydrolyses of β-amino esters with H2O (0.5 equiv.) in t-BuOMe or in i-Pr2O at 45 °C are described. The enantiomers of biologically relevant β-arylalkyl-substituted β-amino acids, and especially (R)-3-amino-3-(2,4,5-trifluorophenyl)butanoic acid, the intermediate of the new antidiabetic drug sitagliptine, were prepared with high enantiomeric excesses (ee≥96%) and in good yields (≥42%). The Royal Society of Chemistry 2010.
- Tasnadi, Gabor,Forro, Enik,Fueloep, Ferenc
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experimental part
p. 793 - 799
(2010/06/20)
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- Candida antarctica lipase B-catalyzed ring opening of 4-arylalkyl-substituted β-lactams
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The Lipolase-catalyzed ring opening of racemic 4-benzyl- 3 and 4-phenylethyl-2-azetidinone 4 was performed with 0.5 equiv of H2O in diisopropyl ether at 45 °C. The resulting (S)-β-amino acid 5 or 6 (ee ≥ 87%) and (R)-β-lactam 7 or 8 (ee >99%) enantiomers could easily be separated. The ring opening of enantiomeric β-lactams with 18% aqueous HCl afforded the corresponding enantiopure β-amino acid hydrochlorides 9 and 10 (ee >99%).
- Tasnadi, Gabor,Forro, Eniko,Fueloep, Ferenc
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p. 2841 - 2844
(2008/03/28)
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- A simple synthesis of β-alkyl-substituted β-amino acids
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By the condensation of branched-chain aliphatic or alicyclic aldehydes with malonic acid in the presence of ammonium acetate, β-alkyl-substituted β-amino acids were prepared.
- Lazar, Laszlo,Martinek, Tamas,Bernath, Gabor,Fueloep, Ferenc
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p. 219 - 224
(2007/10/03)
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- 104. The enantioselective synthesis of β-amino acids, their α-hydroxy derivatives, and the N-terminal components of bestatin and microginin
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L-Aspartic acid by tosylation, anhydride formation, and reduction with NaBH4 was converted into (3S)-3-(tosylamino)butan-4-olide (8; Scheme 1). Treatment of 8 with ethanolic trimethylsilyl iodide gave the N-protected deoxy-iodo-β-homoserine ethyl ester 9. The latter, on successive nucleophilic displacement with lithium dialkylcuprates (→ 10a-e), alkaline hydrolysis (→ 11a-e), and reductive removal of the tosyl group, produced the corresponding 4-substituted (3R)-3-aminobutanoic acids 12a-e (ee >99%). Electrophilic hydroxylation of 8 (→ 19; Scheme 3), subsequent iodo-esterification (→ 21; Scheme 4), and nucleophilic alkylation and phenylation afforded, after saponification and deprotection, a series of 4-substituted (2S,3A)-3-amino-2-hydroxybutanoic acids 24 including the N-terminal acids 24e (= 3) and 24f (= 4) of bestatin and microginin (de >95%), respectively.
- Jefford, Charles W.,McNulty, James,Lu, Zhi-Hui,Wang, Jian Bo
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p. 1203 - 1216
(2007/10/03)
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- An enantiospecific synthesis of β-amino acids
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L-Aspartic acid by regioselective modification of the α-carboxylic acid group, namely N-tosylation, anhydride formation, reduction, iodo-esterification, alkylation, and deprotection afforded a series of γ-alkyl β-aminobutyric acids of the R configuration (ee > 99%).
- Jefford,Wang
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p. 1111 - 1114
(2007/10/02)
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- SYNTHESIS OF 6-ARYL-4-HYDROXYPIPERIDIN-2-ONES AND A POSSIBLE APPLICATION TO THE SYNTHESIS OF A NOVEL HMG-CoA REDUCTASE INHIBITOR
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A series of 6-aryl-4-hydroxypiperidin-2-ones (11a-11g) were synthesised with the key step being a Dieckmann cyclisation of the appropriate methyl 3-(ethoxycarbonylacetylamino)-3-(substituted) propionate (8a-8g) and this new synthetic route was successfully applied to the synthesis of 4-hydroxy-6-(2-phenylethyl)piperidin-2-one (11h).The application of this strategy to the synthesis of the putative HMG-CoA reductase inhibitor 6--4-hydroxypiperidin-2-one (11i) was attempted, but failed during the Dieckmann cyclisation of methyl 3-(ethoxycarbonylacetylamino)- 3-propionate (8i).An alternative synthesis of a 1:1 diastereomeric mixture of (11i) was achieved by the reductive cleavage of the isoxazoline (24) with Raney nickel.The mixture of diastereoisomers (11i) was inactive in-vitro and in-vivo (rat) against HMG-CoA reductase
- Ashton, Michael J.,Hills, Susan J.,Newton, Christopher G.,Taylor, John B.,Tondu, Sylvie C. D.
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p. 1015 - 1035
(2007/10/02)
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