2,2-Dimethyl-propionic acid (1R,2S,6R,7R,8S,9R)-7-benzyloxy-4-(tert-butyl-dimethyl-silanyloxy)-2-methoxy-9-methyl-12-oxo-10-oxa-tricyclo[7.2.1.01,6]dodec-4-en-8-yl ester                                                                                                                                                              在
                                                                                                                                                                                 
硫酸                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
1,4-二氧六环   、                                                                                         
水                                                                                  为溶剂,
                                                                                                                                                                                        以70%的产率得到2,2-Dimethyl-propionic acid (1R,6R,7R,8S,9R)-7-benzyloxy-9-methyl-4,12-dioxo-10-oxa-tricyclo[7.2.1.0
1,6]dodec-2-en-8-yl ester