| 摘要 |
<p>PURPOSE:After a lower alkoxy group is introduced into the 7alpha-position of a specific cephalosporin derivative, the product is converted into another derivative which can be used as a medicine, thus producing the titled compound used as an antibiotic for gram-positive or -negative bacteria with industrial advantage. CONSTITUTION:A lower alkoxy group is introduced into the 7alpha-position of a cepalosporin derivative of formula I [R11 is H, carboxyl-protecting group; R2 is lower alkyl; R31 represents 2 or 3 protected hydroxyls adjacent to one another; R41 is H, pyridinium, -S-R5(R5 is five or six-membered heterocyclic ring containing 1-4 nitrogen and sulfur or oxygen atoms)] and, when R11 is a carboxyl-protecting group, it is eliminated or R11 is converted into salt or ester or the protecting group on the R31 is removed or R41 is converted into -S-R5. At least one reaction cited above is effected to give a compound of formula II (R12 is R11 or others; R32 is R31 or others; R42 is R41; R6 is lower alkoxy).</p> |
