Investigations in the fie ld of substituted furanurona ldehydes steric directivity of the nitromethane condensation
Summary1. The condensation of the anomeric methyl 2,3-di-O-benzyl-D-xylofuranosiduronaldehydes with nitromethane has been studied.2. It has been shown that the position of the substituent at the glycosidic center has an influence on the steric directivity of this reaction.3. The structure of the 6-nitro-6-deoxyhexofuranosides synthesized has been confirmed by their conversion into known derivatives of methyl D-glucofuranosides.
Conversion of d-glucofuranose to l-arabino-hexofuranoside.
Solvolysis of 2, 3-di-O-benzyl-5-O-mesyl-6-O-trityl-D-glucofuranose (IV) was carried out under an oxide ring migration, affording methyl 2, 3-di-O-benzyl-α-L-altrofuranoside (XVIIIa) and its β-anomer (XVIIIb) in a ratio of 1 : 2.2.
Über γ‐Pyrone und γ‐Pyridone, I. Mitteil.: Zur Konstitution der Oxy‐γ‐pyrone und Oxy‐γ‐pyridone
Kojisaure-monomethylather last sich durch Oxydation mit Salpetersaure oder Luftsauerstoff i. Ggw. eines Platin-Katalysators in Komensaure-methylather uberfuhren. Auf einem neuen Wege wird die 5-Stellung der Oxy-Gruppe in den aus Mekonsaure und Kojisaure erhaltenen Pyron- und Pyridonderivaten bestatigt und damit eine neuerdings vertretene abweichende Auffassung widerlegt.