Is No-Tillage Enough? A Field-Scale Watershed Assessment of Conservation Effects

A method of producing a compound represented by the formula: wherein R1 stands for hydrogen or an optionally substituted alkyl or acyl group, which comprises reacting a compound represented by the formula: wherein R1 is of the same meaning as defined above, and R2 stands for an optionally halolgenated alkyl group or an optionally substituted phenyl group with a compound represented by the formula: in a lower alcohol in the presence of an alkali metal or alkaline earth metal carbonate; the compound (III) being useful as starting compounds for producing thiazolidinedione derivatives having hypoglycemic and hypolipidemic activities.