The Kim retrosynthetic analysis of - -reiswigin

Despite the obvious possibilities for disengaging the allylic methyl group of 7 by retro-S reaction, Kim preferred to disjoin this molecule by a (Z)-selective Wittig reaction to obtain aldehyde 9 and ylide 8. Since further analysis of 9 also indicated that it could potentially be reached from the readily available 5-deoxy-D-xylose derivative 10, this was the strategy eventually settled upon. 

With this as background, we now give an account of Kim s synthetic route to (—)-reiswigin A.2 

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