کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1388536 982801 2010 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Selective formation of glycosidic linkages of N-unsubstituted 4-hydroxyquinolin-2-(1H)-ones
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Selective formation of glycosidic linkages of N-unsubstituted 4-hydroxyquinolin-2-(1H)-ones
چکیده انگلیسی

A comparative study for selective glucosylation of N-unsubstituted 4-hydroxyquinolin-2(1H)-ones into 4-(tetra-O-acetyl-β-d-glucopyranosyloxy)quinolin-2(1H)-ones is reported. Four glycosyl donors including tetra-O-acetyl-α-d-glucopyranosyl bromide, β-d-glucose pentaacetate, glucose tetraacetate and tetra-O-acetyl-α-d-glucopyranosyl trichloroacetimidate were tested, along with different promoters and reaction conditions. The best results were obtained with tetra-O-acetyl-α-d-glucopyranosyl bromide with Cs2CO3 in CH3CN. In some cases the 4-O-glucosylation of the quinolinone ring was accompanied by 2-O-glucosylation yielding the corresponding 2,4-bis(tetra-O-acetyl-β-d-glucopyranosyloxy)quinoline. Next, 4-(tetra-O-acetyl-β-d-glucopyranosyloxy)quinolin-2(1H)-ones were deacetylated into 4-(β-d-glucopyranosyloxy)quinolin-2(1H)-ones with Et3N in MeOH. In some instances the deacetylation was accompanied by the sugar–aglycone bond cleavage. Structure elucidation, complete assignment of proton and carbon resonances as well as assignment of anomeric configuration for all the products under investigation were performed by 1D and 2D NMR spectroscopy.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Research - Volume 345, Issue 6, 19 April 2010, Pages 768–779
نویسندگان
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