4- Thio-0 -maltoside

Ethyl l-thio-/3-maltoside heptaaeetate (59) has proved to be a useful intermediate in the synthesis of the a-glycoside of maltose (see Section III).30 Treatment of /3-maltose octaacetate with ethanethiol and fused zinc chloride gave compound 59 in 83% yield. Synthesis of mal-... 

Ethyl 1-thio /J-maltoside 6 -0-trityl-hexa-O-acetyl- 101-103 + 71 C 44... 

The foregoing relationship was utilized in conformational analysis of methyl 4-thio-a-maltoside in solution.153 The VC H values of 2.95 and 5.15 Hz measured151 for H-4 —C-4 —S—C-l—H-l differ from those predicted from Eq. 45 37c 4. h-i = 3.1 Hz and 37C-i,h-4 = 3.8 Hz for the conformation in the crystal154 as defined by H = 25.6° and PH = 3.6°. The observed VC H values were not reproduced by the calculated values for any of the stable conformations of methyl 4-thio-a-maltoside, but are in good agreement with the ensemble average (37c.h) values 2.67 and 5.24 Hz calculated for the compound in water solution, using PCILO-calculated potential surfaces. 

Andrews, J S, Weimar, T, Frandsen, T P, Svensson, B, Pinto, B M, Novel disaccharides containing sulfur in the ring and nitrogen in the interglycosidic hnkage. Conformation of methyl 5 -thio-4-iV-a-maltoside bound to glucoamylase and its activity as a competitive inhibitor, J. Am. Chem. Soc., 117, 10799-10804, 1995. 

Conformational equilibria of thio-oligosaccharides revealed that the most important thiodisac-charide (4-thio-a-maltoside) has a conformation similar to that of the parent maltosyl residue and that the thioglycoside linkage presents a high degree of flexibility. Interestingly, the C-S... 

Preparation of phenyl-2,3,6,2, 3, 4 -hexa-0-benzyl-l-thio-P-D-maltoside. 

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