تحضير مايكروي ودراسة الفعالية البيولوجية لبعض مشتقاث الايميدازوليدين الجديدة للبنزوثيازول

Microwave Synthesis and Study of the Biological Activity for some New Imidazolidine Derivatives of Benzothiazole

   2-Aminobenzothiazole 1 was converted to the corresponding diazonium salt which was introduced in coupling reaction with alkaline solution of 2-hydroxybenzaldehyde as coupling reagent to give azo-benzothiazole derivative 2 bearing aldehyde group. The resulting aldehyde 2 was introduced in condensation reactions with the primary aromatic amines including (4-nitroaniline, 3-nitroaniline, 4-hydroxyaniline, 4-methoxyaniline, 2-methoxyaniline, 4-bromoaniline, 4-chloroaniline and 2,4-dichloroaniline) using microwave irradiation technique in absolute ethanol to produce eight imine derivatives of benzothiazole 3a-h, respectively. The resulting imines 3a-h were treated with both glycine and L-alanine using microwave irradiation in tetrahydrofuran afforded sixteen new imidazolidines 4a-h and 5a-h substituted with benzothiazole moiety, respectively, Scheme (I).
The chemical structures of the target compounds synthesized were deduced from (CHNS) elemental analysis and FT-IR, ¹H NMR spectral measurements. Preliminary in vitro antibacterial activity of the target compounds were investigated using two types of bacteria, Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). The results indicated that the newly synthesized imidazolidines (compounds 4a, 4b, 4c, 4d, 4e, 4g, 4h, 5c, 5d, 5f, 5g, and 5h) exhibited greater activities than gentamycin against Gram-positive bacteria. On the other hand, compounds 4d, 4h, 5c, and 5f also showed better activities against Gram-negative bacteria when compared with that of the control drug (Gentamycin), Figures (3-43)-(3-47).