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                                                                                                                                                              在
                                                                                                                                                                                 sodium tetrahydroborate                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
甲醇   、                                                                                         
水                                                                                  为溶剂,
                                                                                                                                                    反应 0.5h,
                                                                                                                生成                                                 
5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(R)-(hydroxymethyl)avermectin B1b   、                                                                                             
5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(S)-(hydroxymethyl)avermectin B1b   、                                                                                             5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(R)-(hydroxymethyl)avermectin B1a   、                                                                                             5-O-tert-butyldimethylsilyl-7-O-trimethylsilyl-4''-deoxy-4''-(S)-(hydroxymethyl)avermectin B1a