Synthesis and structure of some imines containing furoxan ring derived from isosafrole

A series of 14 imines containing furoxan and benzene rings has been prepared starting from isosafrole. The structure of reported compounds have been confirmed by elemental analysis, El MS, UV, IR, and NMR spectroscopy. It is shown that, on treatment with Na2S2O4, the nitro group on the benzene ring was reduced to amino group, but the N-->O group of the furoxan ring was not. The H-1- and C-13 NMR signals are assigned based on their spin-spin splitting patterns, in some cases, NOESY and HMBC spectra are used. The NOESY spectra indicate that for reported imines, the benzene and the furoxan rings could not be co-planar; the imine group has E-configuration.