54664-61-8Relevant articles and documents
Preparative bioorganic chemistry; 8. Efficient enzymatic preparation of (1R,4S)-(+)-4-hydroxy-2-cyclopentenyl acetate
Sugai,Mori
, p. 19 - 22 (1988)
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Synthesis of (1S,4R)-(-)-40Hydroxy-2-cyclopentenyl Acetate by a Highly Enantioselective Enzyme-Catalyzed Transesterification in Organic Solvents
Theil, Fritz,Ballschuh, Sibylle,Schick, Hans,Haupt, Monika,Haefner, Barbara,Schwarz, Sigfrid
, p. 540 - 541 (1988)
(1S,4R)-(-)-4-Hydroxy-2-cyclopentenyl acetate (2), a versatile intermediate in prostaglandin syntheses, was readily prepared by an efficient enzyme-catalyzed enantioselective monoacetylation of cis-2-cyclopenten-1,4-diol (1) with 2,2,2-trichloroethyl acetate in the organic solvent system triethylamine/tetrahydrofuran.The chemical yield reached nearly 50percent.The enantiomeric excess of the crude product was 95percent.It could be raised to more than 99percent by a single recrystalization.Commercially available pancreatin, a crude enzyme preparation from porcine pancreas, was used as biocatalyst.
Acylative desymmetrization of cyclic meso-1,3-diols by chiral DMAP derivatives
Mandai, Hiroki,Hironaka, Tsubasa,Mitsudo, Koichi,Suga, Seiji
supporting information, p. 471 - 474 (2021/03/15)
An efficient enantioselective acylative desymmetrization of cyclic meso-1,3-diols was developed by using a chiral DMAP derivative 1e having a 1,1¤-binaphthyl unit. The reactions required only 0.5mol% of the catalyst and showed good to excellent enantioselectivity. With this transformation, 5a, a key building block for the synthesis of natural products, was easily obtained in almost enantiomerically pure form after a single recrystallization. Control experiments revealed that tert-alcohol units on the catalyst were responsible for both the catalytic activity and enantioselectivity.
Pd-Catalyzed Asymmetric Allylic Substitution Annulation Using Enolizable Ketimines as Nucleophiles: An Alternative Approach to Chiral Tetrahydroindoles
Xu, Kai,Ye, Jianxun,Liu, Hao,Shen, Jiefeng,Liu, Delong,Zhang, Wanbin
supporting information, p. 2059 - 2069 (2020/04/29)
A synthesis of chiral tetrahydroindoles has been developed via a Pd-catalyzed asymmetric allylic substitution annulation using unstable enolizable ketimines as nucleophiles and our previously developed tBu-RuPHOX as a chiral ligand. The reaction proceeds via an asymmetric desymmetrization of the meso-diacetatecycloalkenes, providing the desired chiral tetrahydroindoles in moderate to good yields and with up to 96% ee. The annulation reaction could be performed on a gram-scale in high yields and the resulting products can be transformed to several types of N-hetereobicyclic derivatives. In addition, a chiral cis-perhydroindolic acid derivative was also readily synthesized starting from a prepared chiral tetrahydroindole. (Figure presented.).
Synthesis of Guanine α-Carboxy Nucleoside Phosphonate (G-α-CNP), a Direct Inhibitor of Multiple Viral DNA Polymerases
Maguire, Nuala M.,Ford, Alan,Balzarini, Jan,Maguire, Anita R.
, p. 10510 - 10517 (2018/09/06)
The synthesis of guanine α-carboxy nucleoside phosphonate (G-α-CNP) is described. Two routes provide access to racemic G-α-CNP 9, one via base construction and the other utilizing Tsuji-Trost allylic substitution. The latter methodology was also applied to the enantiopure synthesis of both antipodes of G-α-CNP, each of which showing interesting antiviral DNA polymerase activity. Additionally, we report an improved multigram scale preparation of the cyclopentene building block 10, starting material for the preferred Tsuji-Trost route to 9.