| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I (R is H or alkanoyl) or salt thereof. EXAMPLE:6,7-Dihydroxyisoquinoline.hydrobromide.monohydrate. USE:A medicine which is a starting raw material for cephalosporin derivatives, expressed by formula II (R<2> is acyl) and having improved antimicrobial action on Gram-negative bacteria, particularly glucose nonfrementative Gram-negative bacilli, e.g. Pseudomonas aeruginosa, Pseudomonas cepacia, Acinetobacter calcoaceticus, etc. PREPARATION:A compound expressed by formula III (R<1> is protecting group of OH except alkanoyl) is boiled in a solution of acetic acid and hydrobromic acid in N2 gas stream at 80-120 deg.C for 2-30hr, cooled and/or concentrated and then hydrolyzed with an acid or a compound expressed by formula II is dissolved in a mixed solution of water, methanol, etc., and catalytically reduced in the presence of Pd/C at 20-80 deg.C for 2-10hr, etc., to remove the protecting groups of the OH groups and, as necessary, acylated to afford the aimed compound expressed by formula I.</p> |
