کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1347248 | 980302 | 2009 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Preparation of isoxazolidinyl nucleoside enantiomers by lipase-catalysed kinetic resolution
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی معدنی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
An efficient biocatalytic procedure to obtain chiral N,O-nucleoside derivatives consisting of a lipase-catalysed resolution of the corresponding racemates in organic solvent has been developed. Enantioselective esterification of thymine and cytosine derivatives, (±)-9a and (±)-9b, has been investigated by comparing the efficiency of different lipases and acyl donors. Since esterification of (±)-9a and (±)-9b, occurred with low enantioselectivity (E ⩽ 14) in the presence of the lipases considered, for preparative purposes we resorted, with success, to a double sequential kinetic resolution, using Lipozyme IM as the best catalyst. This approach enables us to obtain all the enantiomers with ee ⩾ 95%. The absolute configuration of the new chiral N-acetyl cytosine derivative 9b was established by circular dichroism spectroscopy.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Tetrahedron: Asymmetry - Volume 20, Issue 4, 11 March 2009, Pages 425-429
Journal: Tetrahedron: Asymmetry - Volume 20, Issue 4, 11 March 2009, Pages 425-429
نویسندگان
Caterina Carnovale, Daniela Iannazzo, Giovanni Nicolosi, Anna Piperno, Claudia Sanfilippo,