(E)-Ethyl 2-anilino-5-[3-(dimethyl­amino)­acrylo­yl]-4-phenyl­thio­phene-3-carboxyl­ate

In the title compound, C₂₄H₂₄N₂O₃S, the phenyl rings form dihedral angles of 55.65 (11) and 79.60 (11)° with the plane of the thio­phene ring. The mol­ecular conformation is stabilized by an intra­molecular N—H...O hydrogen bond, generating an S(6) ring motif. In the crystal, centrosymmetrically related mol­ecules are linked into dimers by two pairs of C—H...O inter­actions.

Bis­(3,5-diamino-4H-1,2,4-triazol-1-ium) 3,4-dioxocyclo­butane-1,2-diolate

The asymmetric unit of the title compound, 2C₂H₆N₅⁺·C₄O₄²⁻, contains two 3,5-diamino-4H-1,2,4-triazolium cations and one squarate dianion. The squaric acid mol­ecule donated one H atom to each of the two 3,5-diamino-1,2,4-triazole mol­ecules at their N atoms. The squaric acid dianion has four C—O bonds which are shorter than a normal single C—O bond (1.426 Å) and are slightly longer than a normal C=O bond (1.23 Å), which indicates the degree of electron delocalization in the dianion. In the crystal, the cations and dianions are linked by N—H...N and N—H...O hydrogen bonds into a three-dimensional network.

5-Chloro-2-(4-meth­oxy­phen­yl)-1,3-benzo­thia­zole

In the title compound, C₁₄H₁₀ClNOS, the dihedral angle between the benzothia­zole ring system and the meth­oxy-substituted benzene ring is 8.76 (16)°. In the crystal, mol­ecules are stacked in columns along the c axis and no significant inter­molecular inter­actions are observed.

(E)-2,4-Dimethyl-N′-(2-methyl­benzyl­idene)benzohydrazide

In the title benzoyl­hydrazide derivative, C₁₇H₁₈N₂O, the dihedral angle between the benzene rings is 88.45 (8)° and the azomethine double bond adopts an E conformation. In the crystal, mol­ecules are linked by N—H...O and C—H...O hydrogen bonds, forming a chain along the b axis.