Synthesis of New Tetraheterocyclic Systems by the Mixed Condensation Reactions on [1,2,4]Triazolo[4,3‐a][1,5]benzodiazepines

(E)-3-[(Di-methyl-amino)-methyl-idene]-4-phenyl-1-(prop-2-yn-yl)-1H-1,5-benzodiazepin-2(3H)-one

The title compound, C₂₁H₁₉N₃O, exhibits an E configuration with respect to the C=C bond between the benzodiazepine and tri­methyl­amine groups. The seven-membered diazepine ring displays a boat conformation. In the crystal, mol­ecules are linked by a C—H⋯O hydrogen bond, forming a chain along [110].

Diethyl 1,4-bis-(4-nitro-phen-yl)-1,4-dihydro-1,2,4,5-tetra-zine-3,6-dicarboxyl-ate

The complete mol-ecule of the title compound, C(20)H(18)N(6)O(8), is generated by a crystallographic twofold axis. The dihedral angle between the nitrobenzene rings is 43.5 (2)°. The central six-membered ring exhibits a boat conformation. In the crystal structure, weak inter-molecular C-H⋯O inter-actions are observed.