Ouverture par le N-bromosuccinimide des acétals benzylidéniques de méthyl-hexosides de configuration manno et synthèse de la N-acétyl-l-mycosamine
作者:Jean-Claude Florent、Claude Monneret
DOI:10.1016/s0008-6215(00)84674-1
日期:1980.10
6-di-O-benzylidene-α- d -mannofuranoside and methyl 2,3-O-benzylidene-α- l -rharmnofuranoside were prepared according to a newprocedure by simultaneous glycosidation and acetalation of d -mannose and l -rhamnose. Treatment of these compounds and of 1,6-anhydro-2,3-O-benzylidene- d -mannose with N-bromosuccinimide gave exclusively the 3-bromo compounds by regiospecific opening of the acetal ring. Thus, starting from
HPLC Analysis of the Product Distribution in the Iodine-Catalyzed Methyl Glycosidation of Pentoses and 6-Deoxyhexoses
作者:Gyöngyi Gyémánt、András Lipták
DOI:10.1080/07328309808002897
日期:1998.4
The product distribution of the iodine-catalyzed methyl glycosidation of four pentoses (D-ribose, D-arabinose, D-xylose, and D-lyxose) and two 6-deoxyhexoses (L-rhamnose, and D-fucose) was studied by HPLC using an APS column (dihydrogen sulphate form) with different acetonitrile-water mobile phases. In agreement with earlier results, a temperature dependent on-column isomerization was observed for all the investigated aldoses, except for ribose. The first-eluted furanosides were followed by pyranosides, and the free sugars were eluted last with the highest retention volumes.