2-debenzoyl-2-[(R)-3-methylhept-6-enoyl]-7-triethylsilyl-13-[(2R,3S)-3-tertbutoxycarbonylamino-2-triethylsiloxyhept-6-enoyl]baccatin III

7-triethylsilyl-2-debenzoyl-2,13-[(2R,3S,E)-3-tertbutoxycarbonylamino-2-triethylsiloxy-9-oxa-10,11-benzo-1,12-diketododec-6-enylene]baccatin III

7-triethylsilyl-2-debenzoyl-2,13-[(2R,3S,E)-3-tert-butoxycarbonylamino-2-triethylsiloxy-1,10-diketodec-6-enylene]baccatin III

(3R,4S)-1-(tert-butoxycarbonyl)-3-triethylsiloxy-4-(3-butenyl)azetidin-2-one