Shaya Y. Al-Raqa

Halogenated, alkylated and new types of imidazolidine, pyrrolidine, imidazotriazine and thienoimidazole derivatives with biological and antitumor activities

New types of halogenated, alkylated and (bis)cyanothio-formamides were prepared and reacted with iso(thio)cyanates, aldehydes and dibenzylideneacetone to produce (bis)imidazolidine-imino(di)thiones and (oxazolidine and bispyrrolidine)iminothiones, respectively. Imidazolidineimi-nothiones were reacted with H2S/TEA to give thiohydantoin which reacted with p-chlorobenzaldehyde to achieve the corresponding thienoimidazole derivative. Most of the synthesized products exhibited antibacterial, antifungal and antitumor activities.

New Types of Mono and Bis Sulfonamides, Tosylamino Acids and Thiosulfonic Ester Derived from Xanthotoxin, Bergapten and Visnagin with Biological Interest

Xanthotoxin, bergapten, and visnagin sulfonyl chlorides have been reacted with diamines, hydrazine, amino acides, and imidazolidineiminothiones to produce the corresponding mono-, bis-sulfonamide, and tosylamino acid derivatives. Interaction of xanthotoxin-4-sulfonyl chloride with thiohydantoin furnished the respective thiosulfonic ester. The new products exhibited better antibacterial and antifungal activities.

The hexagonal to discotic phase transition in 1,4,8,11,15,18,22,25‐octahexylphthalocyanine studied by differential scanning calorimetry

The phase change in metal‐free 1,4,8,11,15,18,22,25‐octahexylphthalocyanine compound with eight non‐peripheral hexyl chains was investigated under non‐isothermal conditions by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Two endothermic changes were reported. The first one between 332 and 350 K relates to the transition from the hexagonal columnar mesophase to a less ordered crystalline phase, P1. The second endothermic transition from 408 to 417 K is due to the transition to the discotic columnar mesophase, P2. The isoconversional methods of Friedman, and Kissinger, Akahira and Sunose (KAS) were used to determine the variation of the activation energy for crystallisation with temperature, E α(T). Using the Friedman method the average values of E α(T) were 121.31 and 352.77 kJ mol−1 for the first and second peaks, respectively. The KAS method gave higher values of E α(T) with averages of 173.25 and 411.44 kJ mol−1, respectively. The specific heat was measured and found to vary with temperature.

Structural and optical properties of 1, 4, 8, 11, 15, 18, 22, 25-octahexylphthalocyanine: A comparison between thermally evaporated and spin-coated thin films

Abstract Thin films of 1, 4, 8, 11, 15, 18, 22, 25-octahexylphthalocyanine were deposited on glass substrates by the thermal evaporation and spin coating techniques. The structure of the both types of films was found to be in a form. The crystallite size assumed the values of 88.65 and 44.32 nm for thermal and spin coated films, respectively. The surface morphology of the thin films was investigated by atomic force microscopy and showed that the molecules of 1, 4, 8, 11, 15, 18, 22, 25-octahexylphthalocyanine grew in stacks of parallel rows. The optical properties of thermally evaporated and spin coated films are reported here. The spectrophotometric measurements of transmittance and reflectance were carried out at UV-Vis-NIR region for the films that showed two absorption bands, namely the Q- and Soret bands. The mechanism of the optical absorption follows the indirect transitions. Almost there was no remarkable difference was observed between the two types of films. Other optical parameters, such as absorption coefficients α, the absorption index, k, and refractive index, n, were also determined.