الفهرس | Only 14 pages are availabe for public view |
Abstract The chemistry of diarylurea and diarylthiourea derivatives has gained increasing attention due to its diverse pharmacological properties such as antitumor, antiproliferative and antibacterial activity and also as herbicide. Reaction of phenyl isocyanate 1 with different aromatic amines 2 gave the monoadduct 3a-e and the diadduct 4a in case of p-phenylenediamine (Scheme 1). Scheme 1 Similarly reaction of phenyl isothiocyanate 5 with paminoacetophenone 2b gave the monoadduct 6a. However with 2,3-diaminopyridine 2c and o-phenylenediamine 2d gave the monoadducts 6b-c and the diadducts 7a-b. On the other hand, reaction of p-anisidine 2e with the same reagent gave the monoadduct 6e and with p-phenylenediamine 2f gave the diadduct 4b (Scheme 2).Scheme 3 Compound 4b was used as key intermediate for the preparation of compounds 9-11 through its reaction with diethyl malonate, ethyl chloroacetate and phenylhydrazine (Scheme 4).Some of the synthesized compounds were evaluated for their antimicrobial activities. The tested compounds were evaluated against Gram –ve bacteria, Gram +ve bacteria and yeast. The synthesis of urea, thiourea and amide derivatives through three component reaction to study the antitumor activity of some of the synthesized compounds has also been taken into consideration. Thus, reaction of anisaldehyde, resorcinol and acetamide in one pot reaction gave compound 21, in the presence of POCl3 the cyclized compound 22 was obtained. Replacement of acetamide by urea, thiosemicarbazide and thiourea compounds 24, 26 and 28 were obtained respectively (Scheme 9). |