Lee Y C, Stowell C P, Krantz M J
Biochemistry. 1976 Sep 7;15(18):3956-63. doi: 10.1021/bi00663a008.
Cyanomethyl 1-thioglycosides ofD-galactose, D-glucose, 2-acetamido-2-deoxy-D-glucose, and D-mannose were prepared from the respective pseudothiourea derivatives and chloroacetonitrile. The nitrile group in these cyanomethyl thioglycosides can be converted to a methyl imidate group by treatment with sodium methoxide or HC1 in dry methanol to yield 2-imino-2-methoxyethyl 1-thioglycosides (IME-thioglycosides). The factors influencing the yield of IME-thioglycosides were investigated. The most convenient method of preparing IME-thioglycosides was treating 0.1 M cyanomethyl thioglycoside peracetate in dry methanol with 0.01 M sodium methoxide at room temperature for 24-48 h (50-60% yield). These IME-thioglycosides reacted readily with simple amines, amino acids, and proteins in mildly alkaline buffer solutions. Alpha-amylase and lysozyme modified with these reagents under appropriate conditions retained full activities. Thus the IME-thioglycosides constitute a new group of reagents for attaching sugars to proteins.
由相应的假硫脲衍生物和氯乙腈制备了D-半乳糖、D-葡萄糖、2-乙酰氨基-2-脱氧-D-葡萄糖和D-甘露糖的氰甲基1-硫代糖苷。这些氰甲基硫代糖苷中的腈基可通过在无水甲醇中用甲醇钠或HCl处理转化为甲基亚胺酸酯基，生成2-亚氨基-2-甲氧基乙基1-硫代糖苷（IME-硫代糖苷）。研究了影响IME-硫代糖苷产率的因素。制备IME-硫代糖苷最简便的方法是在室温下用0.01 M甲醇钠处理0.1 M全乙酰化的氰甲基硫代糖苷在无水甲醇中24 - 48小时（产率50 - 60%）。这些IME-硫代糖苷在弱碱性缓冲溶液中能与简单胺、氨基酸和蛋白质迅速反应。在适当条件下用这些试剂修饰的α-淀粉酶和溶菌酶保留了全部活性。因此IME-硫代糖苷构成了一类将糖连接到蛋白质上的新型试剂。
