|
|
ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
|
Synthesis and reactions of uronic acid derivatives. XVII. Synthesis of methyl 2-O-(methyl 4-O-methyl-α- and β-D-glucopyranosyluronate)-β-D-xylopyranoside
P. Kováč and R. Palovcik
Inst. Chem., Slovak Acad. Sci., Bratislava
Abstract: Acetolysis of Me (benzyl 2,3-di-O-benzyl-4-O-methyl-β-D-glucopyranosid)uronate gave the anomeric acetates I [R = H, R1 = AcO, R2 = PhCH2 (II); R = AcO, R1 = H, R21 = PhCH2 (III)], which were prepd. in a better overall yield from the corresponding glucopyranosiduronic acid by acid hydrolysis, esterification with CH2N2, and acetylation. Halogenating II and III with HBr or I (R = H, R1 = OH, R2 = PhCH2) with SOCl2 gave I [R = H, R1 = Br, R2 = PhCH2 (IV);RR1 = H,Cl, R2 = PhCH2 (V)], resp. Coupling IV with Me 3,4-di-O-acetyl-β-D-xylopyranoside (VI) in C6H6-CH3NO2 contg. Hg(CN)2 gave disaccharides I [R = H, R1 = R3 (R4 = Ac), R2 = PhCH2] (VII) and I [R = R3(R4 = Ac),R1 = H, R2 = PhCH2] (VIII) in a ratio of 1.4:1; treating V with VI in dry ether contg. AgClO4 gave VII and VIII in α:β-18:1 ratio. Hydrogenolysis of VII and VIII followed by deacetylation gave the aldobiouronic acids I [R = R2 = H, R1 = R3 (R4 = H); R = R3(R4 = H)R1 = R2 = H], which were acetylated to give I [R = H, R1 = R3(R4 = Ac),R2 = Ac; R = R3(R4 = Ac), R1 = H, R2 = Ac].
Full paper in Portable Document Format: 324a501.pdf
Chemical Papers 32 (4) 501–513 (1978)
|