Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Synthesis of 4a‐Carba‐d‐lyxofuranose Derivatives and Their Evaluation as Inhibitors of GH38 α‐Mannosidases

“…[31][32][33][34] In analogy, the preparation of 4a-carba--D-lyxofuranose 14 was commenced from D-lyxose which was initially protected as lyxofuranose 7 according to recognized procedures (Scheme 1). [31][32][33][34] In analogy, the preparation of 4a-carba--D-lyxofuranose 14 was commenced from D-lyxose which was initially protected as lyxofuranose 7 according to recognized procedures (Scheme 1).…”

“…The synthetic approach leading to the key 4a-carba-D-lyxofuranose 14 was based on the combination of literature procedures that employ carbohydrates as the starting materials. [31][32][33][34] In analogy, the preparation of 4a-carba--D-lyxofuranose 14 was commenced from D-lyxose which was initially protected as lyxofuranose 7 according to recognized procedures (Scheme 1). [35,36] Next, nucleophilic addition of vinylmagnesium bromide to an aldehyde group of an open-chain form of 7 afforded diastereomeric diols 8 in 3:1 ratio in almost quantitative yield (Scheme 1).…”

New synthesis of syn-stereodiad building block for polyketides. Formal synthesis of arenamides A and C

“…The reduction of the exocyclic double bond in 3 with hydrogen (1 atm) over a catalytic amount of Pd/C, Pd(OH) 2 /C, or platinum black in methanol or ethyl acetate led to the formation of complex mixtures of difficultly identifiable products. It is known that catalysts based on Group 10 metals (especially palladium catalysts) show a high efficiency in the hydrogenolysis of R-O bonds** in allyl, propargyl, and benzyl substrates and that rhodium-and ruthenium-based catalysts [47,48] and palladium deactivated with triethylamine [49][50][51][52][53][54] are almost inefficient in this respect. The best result in the reduction of 3 was obtained using accessible NiCl 2 -NaBH 4 -MeOH system [55][56][57][58][59] at 0°C.…”