220871-52-3Relevant articles and documents
Convenient method for synthesis of N-protected α-amino epoxides: Key intermediates for HIV protease inhibitors
Blacker, A. John,Roy, Mita,Hariharan, Sivaramkrishanan,Headley, Catherine,Upare, Abhay,Jagtap, Ashutosh,Wankhede, Karuna,Mishra, Sushil Kumar,Dube, Dagadu,Bhise, Sanjay,Vishwasrao, Sandesh,Kadam, Nitin
, p. 331 - 338 (2011)
A convenient method for synthesis of 2R,3S and 2S,3S N-Boc phenylalanine epoxides using readily available allylamine is described. Previous methods employed multistep synthetic routes from l-phenyl alanine that include use of m-chloroperbenzoic acid (m-CPBA) and a chromatographic method for purification of the desired diastereomers. Column purification could be eliminated by bringing in much improvement in the existing process. The process was further enhanced by replacing m-CPBA with oxone, an ecofriendly reagent advantageous for commercial application. The overall green process discussed involves the recovery and recycling of enantiomers of chiral allyl amines and judicial separation of diastereomers of the epoxides using simple economical methods.
Ketone Reductase Biocatalysis in the Synthesis of Chiral Intermediates Toward Generic Active Pharmaceutical Ingredients
Forsyth, Sian M.,Moseley, Jonathan D.,Raynbird, Marina Y.,Sampson, Joanne B.,Smith, Dan A.,Wells, Andrew S.
supporting information, (2020/06/29)
A range of generic active pharmaceutical ingredients were examined for potential chiral alcohol motifs and derivatives within their structures that could be employed as key synthetic intermediates. For seven generic active pharmaceutical ingredients (APIs), eight precursor ketones were acquired and then subjected to reduction by >400 commercially available ketone reductases from different suppliers. Positive screening results were achieved for five ketones screened, with multiple ketone reductases available for each successful ketone. Selectivity was typically >99.5% ee in most cases, including for the opposite enantiomer. The three best examples were then optimized and quickly scaled up to 1 L scale in high conversion and isolated yield while retaining selectivity of >99.5% ee for the desired chiral alcohol enantiomer. This work illustrates that where a wide range of enzymes are available, productive enzymes to give either alcohol enantiomer can be readily identified for many ketones and rapidly scaled up to produce chiral alcohols. This approach is particularly applicable to generating chiral API intermediates.
Synthesis of chiral iodo-N,O-acetonide aminal scaffolds via an efficient cascade reaction of amino acid-derived epoxides
Paige Souder,Evans, Zachary M.,Driver, Joshua A.,Pozzo, Eric J.,Lampkins, Andrew J.
scheme or table, p. 6908 - 6910 (2012/02/15)
Novel amino acid-derived iodo-N,O-acetonide aminals were developed as chiral, non-epimerizable scaffolds to facilitate complex molecule synthesis. These scaffolds are readily prepared from commercially available amino acid derivatives in ≤6 steps, contain an orthogonally-protected β-hydroxy amine moiety, and feature a directly reactive alkyl-iodide group for facile substitution chemistry. Further, a novel ring opening/cyclization cascade reaction was developed to prepare these compounds efficiently (59-72%) from readily available epoxide derivatives.
Highly convergent stereoselective synthesis of chiral key intermediates in the synthesis of Palinavir from imines derived from L-glyceraldehyde
Badorrey, Ramón,Cativiela, Carlos,Díaz-De-Villegas, María D,Gálvez, José A
, p. 341 - 354 (2007/10/03)
Imines derived from O-protected (S)-glyceraldehyde are valuable intermediates in the synthesis of different kinds of amino acids. We have developed a highly convergent and stereoselective method to obtain (2S,3S)-N-tert-butoxycarbonyl-1-phenyl-3,4-epoxy-2-butylamine and (2S,4R)-N-tert-butoxycarbonyl-4-hydroxypipecolic acid tert-butylamide, which are key intermediates in the synthesis of Palinavir, that consist in the treatment of the appropriate imine with benzylmagnesium bromide and Danishefsky's diene, respectively, and subsequent transformation of the obtained adducts into the desired compounds. The reaction of N-benzylimine derived from (S)-2,3-di-O-benzylglyceraldehyde with benzylmagnesium bromide is completely diastereoselective at low temperature. Hetero Diels-Alder reaction of imine derived from (S)-2,3-di-O-benzylglyceraldehyde and (R)-N-α-methylbenzylamine is completely diastereoselective at low temperature in the presence of ZnI2.
Synthesis and antiviral activity of a series of HIV-1 protease inhibitors with functionality tethered to the P1 or P1'phenyl substituents: X-ray crystal structure assisted design
Thompson,Fitzgerald,Holloway,Emini,Darke,McKeever,Schleif,Quintero,Zugay,Tucker,Schwering,Homnick,Nunberg,Springer,Huff
, p. 1685 - 1701 (2007/10/02)
By tethering of a polar hydrophilic group to the P1 or P1' substituent of a Phe-based hydroxyethylene isostere, the antiviral potency of a series of HIV protease inhibitors was improved. The optimum enhancement of anti-HIV activity was observed with the 4-morpholinylethoxy substituent. The substituent effect is consistent with a model derived from inhibitor docked in the crystal structure of the native enzyme. An X-ray crystal structure of the inhibited enzyme determined to 2.25 A verifies the modeling predictions.
