R. Wild, R. Schmidt
May 1, 1995
Citations
0
Influential Citations
29
Citations
Journal
Liebigs Annalen
Abstract
3,4,6-Tri-O-benzyl-D-galactal (3) was directly converted into 3,4,6-tri-O-benzyl-2-deoxy-D-galactose (5). Wittig reaction of 5 with alkyltriphenylphosphonium salts in the presence of n-butyllithium as the base afforded olefins 6a, b which could be readily transformed into phytosphingosines 1a, b via different routes: (i) at first azido group introduction and then double bond and protective group removal, and azido group generation via hydrogenation; (ii) 2-O-mesylation, then double bond and benzyl group removal via hydrogenation, and finally nitrogen introduction; (iii) selective double bond hydrogenation, then nitrogen introduction, and finally benzyl group removal and amino group generation via hydrogenation. Wittig reaction of 5 with alkyltriphenylphosphonium salt in the presence of potassium tert-butoxide as the base afforded diene 7a which proved to be a convenient precursor for sphinganine syntheses; thus, 2-O-mesylation, then double bond and benzyl group removal via hydrogenation and 1,3-O-acetylation, and finally nitrogen introduction and de-O-acetylation afforded 23a. Based on the convenient transformation of D-arabitol into the 1,3-O-benzylidene derivative 25 a further phytosphingosine synthesis is outlined.