1-(4,5-Dihydro-1H-imidazol-2-yl)-2-imidazolidinethione 2-Imidazolidinethione, 1-(4,5-dihydro-1H-imidazol-2-yl)- 3-(2-Imidazoline-2-yl)-2-imidazolidinethione 484-92-4