| 摘要 |
PROBLEM TO BE SOLVED: To provide a chitosan oxide compound useful for a medical treatment material, of which oxidation rate and an acetylation rate are each in a specific range, and of which weight-average molecular weight and a solubility in water are greater than specific values. SOLUTION: The chitosan oxide compound comprises construction unit of formulas I and II, and the compound is derived from chitosan being the formula I/(the formula I + the formula II), (molar ratio) > 70%, an oxidation rate of a CH2OH group in the formulas I and II to a COOX group (wherein X is H, Na or K) being 1-100 mole %, an acetylation rate of a NH2 group to a NHCOCH3 being 40-95 mole %, a weight-average molecular weight being at least 5,000, pH 7, and solubility in water at 25 deg.C being at least 0.1 g/100 g. For example, a chitosan perchlorate is obtained by making an acetate of chitosan, suspending it with conc. acetic acid, adding perchloric acid thereto. A chitosan oxide compound is prepared by adding an oxidation agent to oxidize the chitosan perchlorate, filtering and separating it, dissolving the solids in an alkali solution, adding methanol thereto, then adding acetic anhydride thereto, acetylating and desalting the resulting product.
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