Process for producing tricyclic ketone
AssigneeKabushiki Kaisha Yakult Honsha
InventorsHiroyuki Nishiyama, Seigo Sawada
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Abstract
In order to efficiently supply CPT, which is a starting compound of irinotecan hydrochloride and a variety of camptothecin derivatives, by a practical total synthesis, the invention provides a means of efficiently preparing a tricyclic ketone that corresponds to a CDE ring moiety of a camptothecin (CPT) skeleton.
Claims22
A process for preparing a tricyclic ketone (k), represented by the formula below, for synthesizing camptothecin analogs
- (wherein Me denotes a methyl group, Pr denotes a propyl group, and t-Bu denotes a t-butyl group),
- the process comprising a step (1) of mixing the above compound (a), a compound represented by formula (I)
- (wherein R and R′ are independently alkyl having 1 or 2 carbons, and n is an integer of 1 to 3) and a lithiation reagent, and subsequently mixing with an iodination reagent to give compound (b).
A process for preparing a formylated methoxypyridine derivative by reacting a methoxypyridine derivative with a compound (alkoxyalkylformamide) represented by formula (I)
- (wherein R and R′ are independently alkyl having 1 or 2 carbons, and n is an integer of 1 to 3).
An alkoxyalkylformamide represented by formula (I)
- (wherein R and R′ are independently alkyl having 1 or 2 carbons and n is an integer of 1 to 3, but excluding one in which n is 1 and R and R′ are both methyl, one in which R is methyl and R′ is ethyl and one in which n is 2 and R and R′ are both ethyl).
Dependencies are inferred from the claim text.