| Abstract
| - The spontaneous 1,2-addition of formaldehyde N,N-dialkylhydrazones to carbohydrate-derivedα-alkoxyaldehydes takes place under neutral conditions and in the absence of catalysts or promotersto afford the corresponding α-hydroxyhydrazones in good to excellent yields and with highly antidiastereoselectivities. Subsequent transformations of the hydrazono group into aldehydes andnitriles following known procedures provide a new entry into the homologation of carbohydratesand the synthesis of cyanohydrins, respectively. Additionally, reaction of methyleneaminopyrrolidinewith N-Boc-protected α-aminoaldehydes from natural amino acids efficiently affords the corresponding adducts under the same conditions. From these adducts, a variety of biologically interestingα-hydroxy-β-aminocarbonyl compounds can be accessed upon manipulation of the hydrazone moiety.
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