Previously published / Prédémment paruAsymmetric total synthesis of (+)-exo-brevicomin based on enantioconvergent biocatalytic hydrolysis of an alkene-functionalized 2,3-disubstituted epoxide

2002 ◽  
Vol 80 (6) ◽  
Author(s):  
Sandra F Mayer ◽  
Harald Mang ◽  
Andreas Steinreiber ◽  
Robert Saf ◽  
Kurt Faber

A short total asymmetric synthesis of (+)-exo- and (–)-endo-brevicomin ((+)-exo-3 and (–)-endo-3), which are components of the attracting pheromone system of several bark-beetle species belonging to the genera Dendroctonus and Dryocoetes, was accomplished via a chemoenzymatic protocol. The key step consisted of biocatalytic hydrolysis by bacterial epoxide hydrolases of cis-configured 2,3-disubstituted oxiranes bearing olefinic side chains. This reaction proceeded in an enantioconvergent fashion, by affording a single enantiomeric vic-diol from the rac-epoxide in up to 92% ee and 83% isolated yield.Key words: bacterial epoxide hydrolase, 2,3-disubstituted oxirane, enantioconvergent hydrolysis, (+)-exo-brevicomin, (–)-endo-brevicomin.

2002 ◽  
Vol 80 (4) ◽  
pp. 362-369 ◽  
Author(s):  
Sandra F Mayer ◽  
Harald Mang ◽  
Andreas Steinreiber ◽  
Robert Saf ◽  
Kurt Faber

A short total asymmetric synthesis of (+)-exo- and (–)-endo-brevicomin ((+)-exo-3 and (–)-endo-3), which are components of the attracting pheromone system of several bark-beetle species belonging to the genera Dendroctonus and Dryocoetes, was accomplished via a chemoenzymatic protocol. The key step consisted of biocatalytic hydrolysis by bacterial epoxide hydrolases of cis-configured 2,3-disubstituted oxiranes bearing olefinic side chains. This reaction proceeded in an enantioconvergent fashion, by affording a single enantiomeric vic-diol from the rac-epoxide in up to 92% ee and 83% isolated yield.Key words: bacterial epoxide hydrolase, 2,3-disubstituted oxirane, enantioconvergent hydrolysis, (+)-exo-brevicomin, (–)-endo-brevicomin.


2006 ◽  
Vol 8 (8) ◽  
pp. 1737-1740 ◽  
Author(s):  
Wei Xu ◽  
Jian-He Xu ◽  
Jiang Pan ◽  
Qing Gu ◽  
Xin-Yan Wu

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Xun-Cheng Zong ◽  
Chuang Li ◽  
Yao-Hui Xu ◽  
Die Hu ◽  
Bo-Chun Hu ◽  
...  

Abstract Background Epoxide hydrolase can regioselectively catalyze the oxirane ring-opening hydrolysis of rac-epoxides producing the corresponding chiral diols. In our laboratory, a gene named pveh1 encoding an EH from Phaseolus vulgaris was cloned. Although the directed modification of PvEH1 was carried out, the mutant PvEH1Y3 showed a limited degree of enantioconvergence towards racemic (rac-) m-chlorostyrene oxide (mCSO). Results PvEH1 and PvEH1Y3 were combinatively subjected to laboratory evolution to further enhance the enantioconvergence of PvEH1Y3 towards rac-mCSO. Firstly, the substrate-binding pocket of PvEH1 was identified using a CAVER 3.0 software, and divided into three zones. After all residues in zones 1 and 3 were subjected to leucine scanning, two E. coli transformants, E. coli/pveh1Y149L and /pveh1P184L, were selected, by which rac-mCSO was transformed into (R)-m-chlorophenyl-1,2-ethanediol (mCPED) having 55.1% and 27.2% eep. Secondly, two saturation mutagenesis libraries, E. coli/pveh1Y149X and /pveh1P184X (X: any one of 20 residues) were created at sites Y149 and P184 of PvEH1. Among all transformants, both E. coli/pveh1Y149L (65.8% αS and 55.1% eep) and /pveh1P184W (66.6% αS and 59.8% eep) possessed the highest enantioconvergences. Finally, the combinatorial mutagenesis was conducted by replacements of both Y149L and P184W in PvEH1Y3, constructing E. coli/pveh1Y3Z2, whose αS reached 97.5%, higher than that (75.3%) of E. coli/pveh1Y3. In addition, the enantioconvergent hydrolysis of 20 mM rac-mCSO was performed by E. coli/pveh1Y3Z2, giving (R)-mCPED with 95.2% eep and 97.2% yield. Conclusions In summary, the enantioconvergence of PvEH1Y3Z2 was successfully improved by laboratory evolution, which was based on the study of substrate-binding pocket by leucine scanning. Our present work introduced an effective strategy for the directed modification of enantioconvergence of PvEH1.


2021 ◽  
Vol 22 (9) ◽  
pp. 4993
Author(s):  
Christophe Morisseau ◽  
Sean D. Kodani ◽  
Shizuo G. Kamita ◽  
Jun Yang ◽  
Kin Sing Stephen Lee ◽  
...  

Epoxy-fatty acids (EpFAs) are endogenous lipid mediators that have a large breadth of biological activities, including the regulation of blood pressure, inflammation, angiogenesis, and pain perception. For the past 20 years, soluble epoxide hydrolase (sEH) has been recognized as the primary enzyme for degrading EpFAs in vivo. The sEH converts EpFAs to the generally less biologically active 1,2-diols, which are quickly eliminated from the body. Thus, inhibitors of sEH are being developed as potential drug therapeutics for various diseases including neuropathic pain. Recent findings suggest that other epoxide hydrolases (EHs) such as microsomal epoxide hydrolase (mEH) and epoxide hydrolase-3 (EH3) can contribute significantly to the in vivo metabolism of EpFAs. In this study, we used two complementary approaches to probe the relative importance of sEH, mEH, and EH3 in 15 human tissue extracts: hydrolysis of 14,15-EET and 13,14-EDP using selective inhibitors and protein quantification. The sEH hydrolyzed the majority of EpFAs in all of the tissues investigated, mEH hydrolyzed a significant portion of EpFAs in several tissues, whereas no significant role in EpFAs metabolism was observed for EH3. Our findings indicate that residual mEH activity could limit the therapeutic efficacy of sEH inhibition in certain organs.


2016 ◽  
Vol 14 (24) ◽  
pp. 5639-5651 ◽  
Author(s):  
P. Bauer ◽  
Å. Janfalk Carlsson ◽  
B. A. Amrein ◽  
D. Dobritzsch ◽  
M. Widersten ◽  
...  

Computational studies highlight the importance of conformational diversity in the enantioconvergent hydrolysis of styrene oxide by potato epoxide hydrolase 1.


2018 ◽  
Author(s):  
Marc Montesinos-Magraner ◽  
Matteo Costantini ◽  
Rodrigo Ramirez-Contreras ◽  
Michael E. Muratore ◽  
Magnus J. Johansson ◽  
...  

Asymmetric cyclopropane synthesis currently requires bespoke strategies, methods, substrates and reagents, even when targeting similar compounds. This limits the speed and chemical space available for discovery campaigns. Here we introduce a practical and versatile diazocompound, and we demonstrate its performance in the first unified asymmetric synthesis of functionalized cyclopropanes. We found that the redox-active leaving group in this reagent enhances the reactivity and selectivity of geminal carbene transfer. This effect enabled the asymmetric cyclopropanation of a wide range of olefins including unactivated aliphatic alkenes, enabling the 3-step total synthesis of (–)-dictyopterene A. This unified synthetic approach delivers high enantioselectivities that are independent of the stereoelectronic properties of the functional groups transferred. Our results demonstrate that orthogonally-differentiated diazocompounds are viable and advantageous equivalents of single-carbon chirons<i>.</i>


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