- Regioselective Fluorination of α-Hydroxy-β-aminophosphonates by Using PyFluor
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We report a simple protocol for the synthesis of α-fluoro-β-aminophosphonates by the regioselective fluorination of α-hydroxy-β-aminophosphonates under mild conditions. The fluorination reactions were mediated by the PyFluor reagent and occurred with the retention of configuration. The main products of this reaction were a series of α-fluoro-β-aminophosphonates, which can be used as precursors in the preparation of medicinally important compounds (e.g., dipeptide analogues).
- Ka?mierczak, Marcin,Kubicki, Maciej,Koroniak, Henryk
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p. 3844 - 3852
(2018/07/31)
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- Preparation method of carfilzomib intermediate and intermediate chemical compounds of carfilzomib
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The invention discloses a novel preparation method of a carfilzomib key intermediate. L-leucine is taken as an original raw material, two reactive hydrogen on an amino group are protected, a chemical compound V is prepared and subjected to Weinreb amidation, a chemical compound IV is prepared, IV and 2-allyl magnesium bromide have a reaction, a chemical compound III is prepared and has an epoxidation reaction, a chemical compound II is prepared and subjected to deamination protection, and a chemical compound I is prepared. The invention further discloses intermediate chemical compounds II, III, IV and V of carfilzomib. The preparation method is simple to operate, the total yield is high, the cost is low, the selectivity is high, and the preparation method is suitable for industrial production.
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Paragraph 0076; 0077; 0078; 0079
(2016/10/07)
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- Chiral Pool-Based Synthesis of Naphtho-Fused Isocoumarins
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A variety of chiral derivatives of benzo[d]naphtho[1,2-b]pyran-6-one were prepared in a single step by Et3N-mediated condensation of homophthalic anhydride with different derivatives of (S)-amino acid chlorides at -5 °C by employing a chiral pool methodology. Chirality 27:951-957, 2015.
- Raza, Abdul Rauf,Saddiqa, Aisha,?akmak, Osman
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p. 951 - 957
(2015/11/16)
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- Chiron based synthesis of isocoumarins: Reactivity of α-substituted carboxylic acids
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The asymmetric synthesis of a novel (S)-isocoumarin has been attempted in a single step by the coupling of homophthalic acid with (S)-N-protected amino acids and α-chloroacids at high temperature by exploiting a chiral pool methodology. The coupling of homophthalic acid with N-protected (S)-amino acids gave exclusion of the carboxyl/alkyl group. However, coupling of homophthalic acid with α-chloroacids afforded asymmetric isocoumarins in high yield.
- Saddiqa, Aisha,Raza, Abdul R.,Black, David Stc.,Kumar, Naresh
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p. 736 - 743
(2014/06/09)
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- Stereoselective Synthesis of (3R,4S)-Statine Utilising the Iron Acetyl Complex 5-C5H5)Fe(CO)(PPh3)COOMe> as a Chiral Acetate Enolate Equivalent
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Diethylaluminium enolates derived from the iron acetyl complex 5-C5H5)Fe(CO)(PPh3)COMe> undergo highly diastereoselective aldol reactions with the homochiral aldehydes: N,N-dibenzyl valinal and N,N-dibenzyl leucinal.The diastereoselectivity is explained in terms of Masamune's model of double asymmetric induction using the concept of matched and mismatched pairs.The matched pair aldol product arising from the reaction with N,N-dibenzyl leucinal is converted into the known γ-amino-β-hydroxy acid, (3R,4S)-statine.
- Cooke, Jason W. B.,Davies, Stephen G.,Naylor, Alan
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p. 7955 - 7966
(2007/10/02)
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