کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1386146 982476 2009 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Preparation of sulfated-chitins under homogeneous conditions
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Preparation of sulfated-chitins under homogeneous conditions
چکیده انگلیسی

Sulfated-chitins of varying degrees of sulfation were prepared by the reaction of chitin with sulfur trioxide–pyridine complex under homogeneous conditions in 5% LiCl/DMAc solvent system. Sulfation at 8 °C or room temperature was regio-selective for the C6–OH position with the degree of sulfation (D.S.) ranging from 0.53 to 1.00 depending on the reaction time. When the reaction temperature was elevated, sulfation at the C3–OH position also occurred. The extent of sulfation at the C3 position was a function of the concentration of sulfating reagent, reaction time and temperature. The structure of sulfated-chitins was established by 1H, 13C NMR and 2D HMQC. The degree of sulfation at the C6 position was estimated by 1H NMR while that of the C3 position was by elemental analyses. The anticoagulant activity of the prepared sulfated-chitins correlated closely with D.S. The higher the D.S. yielded, the better the anticoagulant activity. In particular, a continuous sequence of 36S units was critical for obtaining high anticoagulation activity.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Polymers - Volume 77, Issue 3, 11 July 2009, Pages 516–525
نویسندگان
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