A-Manno-type analogue

In contrast, in the case of the s)uithesis of the a-manno-type analogue, hydrogenolysis of isoxazoline 14a which is desired to obtain compound 8 was conducted using Raney nickel and B(0H)3 to furnish the desired keto-alcohol 16 in a quantitative yield (O Scheme 2). 

These keto-alcohols 15 and 16 were converted into 1,6-epi-cyclophelitol (7) and the 1,2,6-epi-cyclophelitol a-manno-type analogue (8), respectively, according to the synthetic route shown in O Scheme 3. 

---