摘要 |
The present invention relates to a process for the preparation of a compound of formula (I), hydrates or solvates thereof; (I) said process comprising the steps of a) reacting a compound of formula (II), with an acylating or a silylating agent to produce a compound of formula (III), (II) (III) wherein P1 is a protecting group selected from R1CO-, or R2Si(R3)(R4)-, P2 is a protecting group selected from (R6R5R7)C-CO-, or (R2)Si(R3)(R4)-, wherein R1 is a group selected from C1-6alkyl or C3-6cycloalkyl, each group being optionally substituted by one or more substituents independently selected from fluoro or C1-4alkyl; R2, R3 and R4 are each independently a group selected from C1-6alkyl or phenyl, each group being optionally substituted by one or more substituents independently selected from fluoro or C1-4alkyl; R5 is a group selected from C1-6alkyl or phenyl, each group being optionally substituted by one or more substituents independently selected from fluoro or C1-4alkyl; R6 and R7 are each independently hydrogen or a group selected from C1-6alkyl or phenyl, each group being optionally substituted by one or more substituents independently selected from fluoro or C1-4alkyl; b) reacting the compound of formula (III) in the presence of at least one oxidizing agent selected from permanganate salt, osmium oxide, hydrogen peroxide, or iodine and silver acetate to produce compound of formula (IV); and (IV)5 c) deprotecting the compound of formula (IV) to produce compound of formula (I). |