Two new synthetic products of antibiotic interest have been prepared by condensing 1,3- or 1,4-cyclohegane-dione respectively with aminoguanidine nitrate in the presence of acetic acid. The 1,3-derivative has been isolated as free base (Ⅱ) in the form of brilliant yellow needles, m. p. 2600 (decomp.), exhibiting distinct Sakaguchi's reaction; the 1,4-derivative forms a nitrate (Ⅲ°2HNO₃), lemon-yellow crystals, m.p.2300 (decomp.).