5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-exo-(Z-isocyanomethylene)avermectin B1b 、 5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-exo-(E-isocyanomethylene)avermectin B1b 、 5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-exo-(Z-isocyanomethylene)avermectin B1a 、 5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-exo-(E-isocyanomethylene)avermectin B1a 在
lead(IV) tetraacetate 作用下,
以
苯 为溶剂,
反应 2.0h,
生成
5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(R)-formylavermectin B1b 、
5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(S)-formylavermectin B1b 、 5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(R)-formylavermectin B1a 、 5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(S)-formylavermectin B1a