127911-70-0Relevant articles and documents
Deracemization of 1,2-diol monotosylate derivatives by a combination of enzymatic hydrolysis with the Mitsunobu inversion using polymer-bound triphenylphosphine
Shimada, Yasutaka,Usuda, Kazumasa,Okabe, Hirokazu,Suzuki, Tsuguru,Matsumoto, Kazutsugu
experimental part, p. 2802 - 2808 (2010/03/30)
The deracemization of 1,2-diol monotosylate derivatives is achieved by the sequential combination of enzymatic hydrolysis and Mitsunobu inversion using a polymer-bound triphenylphosphine. After the lipase-catalysed hydrolysis of the racemic 2-acetoxyhexyl tosylate, the subsequent Mitsunobu reaction without separation causes an inversion of the resulting (R)-alcohol to give the (S)-enantiomer of the acetate as a single product. In particular, the reaction using the polymer-bound triphenylphosphine also proceeds smoothly, and the product is easily separated by filtration from the polymer-bound reagent and its by-products. This deracemization process is applicable to the preparation of several optically active 1,2-diol monotosylates.
Preparation of optically active 1,2-diol monotosylates by enzymatic hydrolysis
Shimada, Yasutaka,Sato, Hiroshi,Minowa, Shinji,Matsumoto, Kazutsugu
, p. 367 - 370 (2008/04/01)
An easy preparation of optically active 1,2-diol monotosylate derivatives by enzymatic hydrolysis is disclosed. Lipase PS (Burkholderia cepacia) catalyzes the hydrolysis of racemic 2-acetoxyhexyl tosylate with excellent enantioselectivity to afford the corresponding optically active compounds. In this reaction, a unique temperature effect is observed. After optimizing the reaction conditions, this procedure is widely applicable to the practical preparation of both enantiomers of various optically active compounds with high ee. Georg Thieme Verlag Stuttgart.
New Alkaloids from Ants: Identification and Synthesis of (3R,5S,9R)-3-Butyl-5-(1-oxopropyl)indolizidine and (3R,5R,9R)-3-Butyl-5-(1-oxopropyl)indolizidine Constituents of the Poison Gland Secretion in Myrmicaria eumenoides (Hymenoptera Formicidae)
Francke, Wittko,Schroeder, Frank,Walter, Felix,Sinnwell, Volker,Baumann, Horst,Kaib, Manfred
, p. 965 - 978 (2007/10/02)
The (3R,5S,9R) and (3R,5R,9R) stereoisomers of 3-butyl-5-(1-oxopropyl)indolizidine (9) were identified as major constituents of the poison gland secretion of the African ant, Myrmicaria eumenoides.Racemates of the four diastereomers of 9 were synthesized via the corresponding ethyl 5-(5-butylpyrrolidin-2-yl)pentanoates (6).Enantiomerically pure samples of the (3R)-stereoisomers of 9 were obtained by starting from (2R)-2,3-O-isopropylideneglyceric aldehyde (21) and 6-methylpyridine-2-carboxaldehyde (20).In addition, the enantiomeric separation by chiral gas chromatography and unambiguous structure assignment of the target compounds are described. - Key Words: Ants/ Alkaloids/ Myrmicaria eumenoides/ 3-Butyl-5-(1-oxopropyl)indolizidine, (3R,5S,9R)-, (3R,5R,9R)-
A CHEMOENZYMATIC ACCESS TO OPTICALLY ACTIVE 1,2-EPOXIDES
Chen, Ching-Shih,Liu, Yeuk-Chuen
, p. 7165 - 7168 (2007/10/02)
Lipase-catalyzed transacylation in organic media was employed to produce optically active α-hydroxy tosylate which could be readily converted to the corresponding 1,2-epoxides with high optical purity.
