2-Eth-oxy-4-[2-(3-nitro-phen-yl)-hydrazono-meth-yl]phenol.

The title Schiff base compound, C(15)H(15)N(3)O(4), was prepared from a condensation reaction of 3-eth-oxy-4-hydroxy-benz-aldehyde and 3-nitro-phenyl-hydrazine. The mol-ecule is nearly planar; the dihedral angle between the hydroxy-benzene ring and the nitro-benzene ring is 6.57 (7)°.

N'-(But-2-enyl-idene)-iso-nicotino-hydrazide.

In the title Schiff base compound, C(10)H(11)N(3)O, the pyridine ring is twisted with respect to the mean plane containing the hydrazine chain, making a dihedral angle of 31.40 (9)°. The NH group inter-acts with the N atom of the pyridine ring through N-H⋯N hydrogen bonds to build up a zigzag chain developing parallel to the (01) plane.