| 摘要 |
<p>PURPOSE:To simply obtain the title compound useful as anti-inflammatory agent, analgesic, etc., in the number of steps fewer than the usual number of steps and high yield by halogenating a specific raw material compound and subjecting the product to ring-closing reaction. CONSTITUTION:A compound expressed by formula I is halogenated normally using a halogenating agent such as thionyl chloride and then the resultant compound expressed by formula II (X is halogen) is subjected to ring closing reaction in the presence of a catalyst such as aluminum chloride in an organic solvent such as dichloromethane under reflux conditions to provide the aimed 2-(5H-[1]benzopyrano[2,3-b]pyridine-7-yl)propionic acid expressed by formula III. Furthermore, a raw material compound expressed by formula I is preferably obtained by reducing a compound expressed by formula IV [Z is CN or COOR (R is lower alkyl)] and then hydrolyzing the resultant product.</p> |
