The novel (EE)-dioxime, 5,6:17,18-dibenzo-11,12-(4'-nitrobenzo)-2,3-bis(hydroxyimino)-7,16-dithia-10,13-dioxa-1,4-diazacyclooctadecane) (H2L), has been synthesized from reaction of (EE)-dichloroglyoxime (1) with 2,3:14,15-dibenzo 8,9-(4'-nitrobenzo)-4,13-dithia-7,10-dioxa-1,16-diazahegzadecane (2). The mononuclear Co(III) complex (4) of this dioxime was prepared by oxidation of the cobalt (11) complex. The BF2+-capped Co(III) complex (5) was synthesized by using a precursor Co(III) complex and boron trifluoride dietherate. The heterotrinuclear complexes (6) and (7) were prepared by reaction of (5) with NiCl2 . 6H(2)O and CdCl2 . H2O, respectively. In addition, the homotrinuclear Cu(II) complex (8), has also been prepared by the reaction of this dioxime with CuCl2 . H2O. The structures of the dioxime and its complexes were identified by using elemental analysis, H-1- and C-13-NMR, IR, and mass spectral data.