| 摘要 |
<p>PURPOSE:To obtain a new compound useful as an intermediate capable of simply synthesizing a new maltose derivative which is readily subjected to introduction of amino group to the 2'-position, sulfation at the 6'-position and glycosylation at the 4'-position and suitable for synthesizing a repeated disaccharide constituting heparin. CONSTITUTION:A compound of formula I (R<1> is protecting group; R<2> to R<4> are H, acyl, etc.; R<5> to R<8> are H, alkyl, etc.) such as phenyl-2',3:4',6'-di-0- benzylidene-a-maltoside. The compound is obtained by reacting a maltose derivative of formula II (R<9> is protecting group) with an acetal compound or a ketal compound of formula III (R<10> and R<11> are H, phenyl, etc.; R<12> and R<13> are H or cycloalkyl) (e.g. benzaldehyde dimethyl acetal or 2,2-dimethoxypropane) preferably in the presence of an acid catalyst such as p-toluenesulfonic acid. The reaction is preferably carried out in an aprotic organic solvent such as OMF at pH<=4 at 0-100 deg.C for 1-10 hours.</p> |
