| 摘要 |
<p>The invention described herein pertains to processes for preparing tubulysin derivatives, conjugates of tubulysins, and intermediates therefore. In one illustrative embodiment of the invention, processes for derivatives or analogs of natural tubulysins including compounds of formula (T). In another embodiment, vitamin receptor binding conjugates of tubulysins are described. The processes include one or more steps described herein. In another embodiment, a process is described for preparing a compound of formula B, wherein R5 and R6 are as described in the various embodiments herein, such as each being independently selected from optionally substituted alkyl or optionally substituted cycloalkyl; and R8 is C1-C6 n-alkyl; wherein the process comprises the step of treating a compound of formula A with a silylating agent, such as triethylsilyl chloride, and a base, such as imidazole in an aprotic solvent.</p> |
