3- Amino-oxaphosphinanes

The direct synthesis of amino-oxaphosphinanes 160 and 161 was performed starting from alkylamino-arabinofuranose 159, directly obtained by the treatment of... 

Scheme 34 Synthesis of amino oxaphosphinanes 160a and 161a...

By contrast, better diastereoselectivity was observed in the synthesis of 3-amino-oxaphosphinanes 42a and 42b (Scheme 9). Then mixing alkylamino-arabinofuranoses 41, directly prepared from the reaction of 2,3,5-tri-O-benzyl-D-arabinofuranose 38 with an excess of a primary amine (i.e., benzylamine or aUylamine), gave mainly one diastereomer with a glucosamine-like stereochemistry (42a or 42b). 

Aminophosphonylation of a y-hydroxyketone leads to phosphonic analogues of a-methyl-homoserine, which can be cyclized to the 2-alkoxy-3-amino-l, 2-oxaphosphinane oxides (284) (Equation (18)) <93PS(81)17>. 

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