| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new compound useful as an intermediate for producing a specific carcinostatic antibiotic. SOLUTION: A compound of formula I (R2, R3 are each H or a lower alkyl; R4 is a lower alkyl), for example, 3-formyloxymethyl-6-methoxy-8-hydroxy-1H-2- benzopyran-1-one. The compound of formula I is obtained, for example, by treating a compound of formula II (R1 is H or a lower alkyl; L is an eliminable group) (for example, 3-benzyloxymethyl-6,8-dimethoxy-1H-2-benzopyran-1-one) with a Lewis acid such as BBr3 and subsequently reacting the obtained compound with a compound of the formula: R3-COOX (X is H, an alkali metal or the like) (for example, sodium formate) in a solvent such as dimethylformamide preferably at -5 to 50 deg.C for 1-24 hr. The compound formula I is subjected to a hydrolysis treatment to give a carcinostatic biotic MI43-37F11. |
