Interference No. 103,675
derivative." The compound depicted by formula I is a 7-fluoro taxol
derivative. According to Chen et al.'s disclosure, different isomeric
ratios of the 7-fluoro derivative may be obtained depending on
reaction conditions. For example, the choice of solvent was found to
influence the ratio of "- and ß-isomers produced, ethereal solvents
favoring "-isomers compared to halogenated solvents (see page 5, lines
17 through 32). Chen et al. disclose various reaction schemes for the
synthesis of the 7-fluoro taxol derivatives (see page 5, line 17
through the end of page 14), and there are 9 (nine) examples of
compounds prepared according to Chen et al.'s disclosure (see page 18
through page 32, line 32).
In Example 2, a 1:1 mixture of 7-"- and 7-ß-isomers of a 7-
fluoro taxol derivative according to formula I were prepared from the
compound of Example 1. In Example 3, the compound prepared in Example
2 was used to prepare a mixture of "- and ß-isomers of a 7-fluoro
taxol derivative with the 2'-hydroxy protecting group removed. In
Example 4, the compound prepared in Example 1 was used to prepare an
hydroxy protected 7-"-fluorotaxol derivative which was subsequently
deprotected as in Example 3. In Example 5, a mixture of 7-fluoro taxol
isomers was used to prepare a 7-fluoro baccatin derivative (see
compound IV on page 11 of the specification). The intermediate was
used to prepare a protected 7-fluoro taxol derivative of the formula V
15
Page: Previous 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Next
Last modified: November 3, 2007