1,3,4-Oxadiazole-2(3H)-thione, 3-(((4-nitrophenyl)amino)methyl)-5-(4-pyridinyl)- 3-(((4-Nitrophenyl)amino)methyl)-5-(4-pyridinyl)-1,3,4-oxadiazole-2(3H)-thione 84249-83-2