Ester 1 is one of the most important functional groups in organic synthesis. Furthermore, the imidate 2, an imino analogue of esters, has recently received much attention due to their interesting reactivities. [1] In contrast, little is known about the chemistry of hydroximate 3, N-alkoxyimidate which is expected to be a reactive synthon based on a combination of two types of heteroatoms and existence of two geometrical E- and Z-isomers in the hydroximates. [2] We now report the first example of radical cyclization of the dienes [3] connected with the hydroximates which are indispensable to cyclization and lactone synthesis. The corresponding dienes connected with ester did not undergo the radical cyclization. The newly found radical cyclization of the hydroximates provides an alternative method for the construction of butyrolactones [4] which were effectively derived by hydrolysis of the cyclic hydroximates.