AbstractA number of 1‐(tetrahydro‐2‐furyl)uracils, cytosines and related compounds were synthesized by a modified Hilbert‐Johnson method from 2‐chlorotetrahydrofuran and the corresponding 2,4‐dimethoxypyrimidines. The relative stability in acid of tetrahydrofuryl and tetrahydropyranyl moieties in compounds of this type was discussed. 2‐Oxo‐4‐methoxy‐1,2‐dihydropyrimidine, a compound which has been erroneously reported, has now been prepared and its structure confirmed by con