Crystal structures and antibacterial activity of hydrazone derivatives from 1H-indol-3-acetohydrazide

A series of three new hydrazone derivatives C₂₂H₁₉N₃O₂ (1), C₁₇H₁₃ClN₄O₃ (2), and C₂₁H₂₄N₄O₂·CH₄O (3) obtained by the condensation of ¹H-indol-3-acetohydrazide with 2-methoxynaphthaldehyde, 2-chloro-5-nitrobenzaldehyde, and 4-diethylaminosalicylaldehyde, respectively, in methanol, ia prepared. The compounds are characterized by elemental analysis, IR spectra, ¹H NMR spectra, and single crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group P2₁/n with unit cell dimensions a = 17.740(2) Å, b = 5.621(1) Å, c = 18.573(3) Å, β = 92.659(2)°, V = 1850.0(6) ų, Z = 4, R ₁ = 0.0610 and wR ₂ = 0.1155. Compound 2 crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 29.178(2) Å, b = 8.195(1) Å, c = 14.372(1) Å, β = 109.446(2)°, V = 3240.5(5) ų, Z = 8, R ₁ = 0.0452 and wR ₂ = 0.1028. Compound 3 crystallizes in the monoclinic space group Pc with unit cell dimensions a = 6.579(1) Å, b = 15.112(2) Å, c = 10.676(2) Å, β = 90.030(2)°, V = 1061.4(3) ų, Z = 2, R ₁ = 0.0535 and wR ₂ = 0.1123. The single crystal X-ray structural determination reveals that the molecules of the compounds are much twisted due to the lack of efficient conjugation. Preliminary biological tests indicate that the compounds are effective antibacterial material.