A Short Synthesis of Dihydroxyspirohydantoins from 1,5-Dialdehydes

Abstract

α-Amino nitriles 3 a,b obtained by cyclization of pentanedial (1a) or 2,2'-oxydiacetaldehyde (1b) with cyanoacetamide and Hofmann rearrangement were converted into the corresponding 6,10-dihydroxy- t,3-diazaspiro[4,5]decane-2,4-diones 4 c,d by sequential treatment with chlorosulfonyl isocyanate, hydrolysis, acetylation and deacetylation