37577-07-4Relevant articles and documents
High Regio- and Stereoselective Multi-enzymatic Synthesis of All Phenylpropanolamine Stereoisomers from β-Methylstyrene
Corrado, Maria L.,Knaus, Tanja,Mutti, Francesco G.
, p. 2345 - 2350 (2021)
We present a one-pot cascade for the synthesis of phenylpropanolamines (PPAs) in high optical purities (er and dr up to >99.5 %) and analytical yields (up to 95 %) by using 1-phenylpropane-1,2-diols as key intermediates. This bioamination entails the combination of an alcohol dehydrogenase (ADH), an ω-transaminase (ωTA) and an alanine dehydrogenase to create a redox-neutral network, which harnesses the exquisite and complementary regio- and stereo-selectivities of the selected ADHs and ωTAs. The requisite 1-phenylpropane-1,2-diol intermediates were obtained from trans- or cis-β-methylstyrene by combining a styrene monooxygenase with epoxide hydrolases. Furthermore, in selected cases, the envisioned cascade enabled to obtain the structural isomer (1S,2R)-1-amino-1-phenylpropan-2-ol in high optical purity (er and dr >99.5 %). This is the first report on an enzymatic method that enables to obtain all of the four possible PPA stereoisomers in great enantio- and diastereo-selectivity.
Regio- and stereoselective multi-enzymatic aminohydroxylation of β-methylstyrene using dioxygen, ammonia and formate
Corrado, Maria L.,Knaus, Tanja,Mutti, Francesco G.
, p. 6246 - 6251 (2019/12/03)
We report an enzymatic route for the formal regio- and stereoselective aminohydroxylation of β-methylstyrene that consumes only dioxygen, ammonia and formate; carbonate is the by-product. The biocascade entails highly selective epoxidation, hydrolysis and hydrogen-borrowing alcohol amination. Thus, β-methylstyrene was converted into 1R,2R and 1S,2R-phenylpropanolamine in 59-63% isolated yields, and up to >99.5 : 0.5 dr and er.
Efficient 2-step biocatalytic strategies for the synthesis of all nor(pseudo)ephedrine isomers
Sehl, Torsten,Hailes, Helen C.,Ward, John M.,Menyes, Ulf,Pohl, Martina,Rother, Doerte
supporting information, p. 3341 - 3348 (2014/06/10)
Chiral 1,2-amino alcohols are important building blocks for chemistry and pharmacy. Here, we developed two different biocatalytic 2-step cascades for the synthesis of all four nor(pseudo)ephedrine (N(P)E) stereoisomers. In the first one, the combination of an (R)-selective thiamine diphosphate (ThDP)-dependent carboligase with an (S)- or (R)-selective ω-transaminase resulted in the formation of (1R,2S)-NE or (1R,2R)-NPE in excellent optical purities (ee >99% and de >98%). For the synthesis of (1R,2R)-NPE, space-time yields up to ~26 g L-1 d-1 have been achieved. Since a highly (S)-selective carboligase is currently not available for this reaction, another strategy was followed to complement the nor(pseudo)ephedrine platform. Here, the combination of an (S)-selective transaminase with an (S)-selective alcohol dehydrogenase yielded (1S,2S)-NPE with an ee >98% and a de >99%. Although lyophilized whole cells are cheap to prepare and were shown to be appropriate for use as biocatalysts, higher optical purities were observed with purified enzymes. These synthetic enzyme cascade reactions render the N(P)E-products accessible from inexpensive, achiral starting materials in only two reaction steps and without the isolation of the reaction intermediates. This journal is the Partner Organisations 2014.