Synthesis, X-ray, NMR, FT-IR, UV/vis, DFT and TD-DFT studies of N-(4-chlorobutanoyl)-N'-(2-, 3- and 4-methylphenyl)thiourea derivatives.

A new isomers of thiourea derivatives, namely N-(4-chlorobutanoyl)-N'-(2-methylphenyl)-thiourea (1a), N-(4-chlorobutanoyl)-N'-(3-methylphenyl)thiourea (1b) and N-(4-chlorobutanoyl)-N'-(4-methylphenyl)thiourea (1c) have been synthesized by refluxing mixture of equimolar amounts of 4-chlorobutanoylisothiocyanate with 2, 3 or 4-toluidine, respectively. The three isomers were characterized by spectroscopic (UV/vis, FT-IR and NMR) and X-ray crystallography techniques. To investigate the isomerization effect on spectroscopic data, DFT and TD-DFT calculations have been carried out using five hybrid functionals (B3LYP, B3P86, CAM-B3LYP, M06-2X and PBE0) to predict UV/vis absorption bands (n→π∗ and π→π∗), (1)H and (13)C NMR chemical shifts, FT-IR vibration modes and X-ray parameters (bonds, bond angles and torsion angles) for 1a, 1b and 1c isomers. The results showed that the isomerization effect is significant on λ(MAX) absorption bands, while for IR and NMR the effect is negligible. In accordance with previous studies, B3LYP, B3P86 and PBE0 gave the most reliable to predict the excitation energies of thiourea derivatives.

1-(4-Chloro-butano-yl)-3-(3-chloro-phen-yl)thio-urea.

The two independent mol-ecules in the asymmetric unit of the title compound, C11H12Cl2N2OS, exhibit different conformations, with the benzene ring and the N2CS thio-urea group forming dihedral angles of 87.40 (18) and 69.42 (15)°. An intra-molecular N-H⋯O hydrogen bond is present in each mol-ecule. Two further N-H⋯O hydrogen bonds link the independent mol-ecules into a dimer. In the crystal, the dimers are linked by N-H⋯S and C-H⋯S hydrogen bonds, forming chains parallel to the c axis.

1-(4-Bromo-phen-yl)-3-(3-chloro-propan-oyl)thio-urea.

The title compound, C10H10BrClN2OS, adopts a trans-cis conformation with respect to the position of the 3-chloro-propanoyl and 4-bromo-phenyl groups, respectively, against the thiono C=S bond across their C-N bonds. The benzene ring makes a dihedral angle of 9.55 (16)° with the N2CS thio-urea moiety. Intra-molecular N-H⋯O and C-H⋯S hydrogen bonds occur. In the crystal, mol-ecules are linked into chains along the c-axis direction by N-H⋯S, C-H⋯S and C-H⋯O hydrogen bonds.

Synthesis, characterization, X-ray structure and biological activities of C-5-bromo-2-hydroxyphenylcalix[4]-2-methyl resorcinarene.

C-5-bromo-2-hydroxyphenylcalix[4]-2-methylresorcinarene (I) was synthesized by cyclocondensation of 5-bromo-2-hydroxybenzaldehyde and 2-methylresorcinol in the presence of concentrated HCl. Compound I was characterized by infrared and nuclear magnetic resonance spectroscopic data. X-ray analysis showed that this compound crystallized in a triclinic system with space group of Pi, a = 15.9592(16)Å, b = 16.9417(17)Å, c = 17.0974(17)Å, α = 68.656(3)°, ß = 85.689(3)°, γ = 81.631(3)°, Z = 2 and V = 4258.6(7)Å3. The molecule adopts a chair (C2h) conformation. The thermal properties and antioxidant activity were also investigated. It was strongly antiviral against HSV-1 and weakly antibacterial against Gram-positive bacteria. Cytotoxicity testing on Vero cells showed that it is non-toxic, with a CC50 of more than 0.4 mg/mL.