56613-80-0Relevant articles and documents
Reactive extraction of enantiomers of 1,2-amino alcohols via stereoselective thermodynamic and kinetic processes
Tang, Lijun,Choi, Sujung,Nandhakumar, Raju,Park, Flyunjung,Chung, Hyein,Chin, Jik,Kwan, Mook Kim
, p. 5996 - 5999 (2008)
(Chemical Equation Presented) (R)-Amino alcohol with an enantiomeric excess of >95% was resolved by reactive extraction processes from 2 equiv of racemic alcohol using a chiral receptor 2 as an enantioselective extractant. One resolution cycle is composed of three extractions: a stereoselective reversible imine formation, a stereoselective irreversible imine hydrolysis, and the recovery of 2 and enantiomeric amino alcohols.
Bioproduction of Enantiopure (R)- and (S)-2-Phenylglycinols from Styrenes and Renewable Feedstocks
Sekar, Balaji Sundara,Mao, Jiwei,Lukito, Benedict Ryan,Wang, Zilong,Li, Zhi
, p. 1892 - 1903 (2020/12/22)
Enantiopure (R)- and (S)-2-phenylglycinols are important chiral building blocks for pharmaceutical manufacturing. Several chemical and enzymatic methods for their synthesis were reported, either involving multi-step synthesis or starting from a relatively complex chemical. Here, we developed one-pot simple syntheses of enantiopure (R)- and (S)-2-phenylglycinols from cheap starting materials and renewable feedstocks. Enzyme cascades consisting of epoxidation-hydrolysis-oxidation-transamination were developed to convert styrene 2 a to (R)- and (S)-2-phenylglycinol 1 a, with butanediol dehydrogenase for alcohol oxidation as well as BmTA and NfTA for (R)- and (S)-enantioselective transamination, respectively. The engineered E. coli strains expressing the cascades produced 1015 mg/L (R)-1 a in >99% ee and 315 mg/L (S)-1 a in 91% ee, respectively, from styrene 2 a. The same cascade also converted substituted styrenes 2 b–k and indene 2 l into substituted (R)-phenylglycinols 1 b–k and (1R, 2R)-1-amino-2-indanol 1 l in 95–>99% ee. To transform bio-based L-phenylalanine 6 to (R)-1 a and (S)-1 a, (R)- and (S)-enantioselective enzyme cascades for deamination-decarboxylation-epoxidation-hydrolysis-oxidation-transamination were developed. The engineered E. coli strains produced (R)-1 a and (S)-1 a in high ee at 576 mg/L and 356 mg/L, respectively, from L-phenylalanine 6, as the first synthesis of these compounds from a bio-based chemical. Finally, L-phenylalanine biosynthesis pathway was combined with (R)- or (S)-enantioselective cascade in one strain or coupled strains, to achieve the first synthesis of (R)-1 a and (S)-1 a from a renewable feedstock. The coupled strain approach enhanced the production, affording 274 and 384 mg/L (R)-1 a and 274 and 301 mg/L (S)-1 a, from glucose and glycerol, respectively. The developed methods could be potentially useful to produce these high-value chemicals from cheap starting materials and renewable feedstocks in a green and sustainable manner. (Figure presented.).
General Method for the Asymmetric Synthesis of N-H Sulfoximines via C-S Bond Formation
Argent, Stephen P.,Lewis, William,Mendon?a Matos, Priscilla,Moore, Jonathan c.,Stockman, Robert A.
supporting information, (2020/03/30)
A versatile method for the synthesis of enantioenriched N-H sulfoximines is reported. The approach stems from the organomagnesium-mediated ring opening of novel cyclic sulfonimidate templates. The reactions proceed in high yield and with excellent stereofidelity with alkyl, aryl, and heteroaryl Grignard reagents. The chiral auxiliary is readily removed from the resultant sulfoximines via an unusual oxidative debenzylation protocol that utilizes molecular oxygen as the terminal oxidant. This provides a general strategy for the synthesis of highly enantioenriched N-H sulfoximines.