title: Synthesis and antibacterial activities of novel 2,5-diphenylindolo[2,3-e] pyrazolo[1',5':3",4"]pyrimido[2",1"-c] [1,2,4]triazines.
abstract: The formation of (E)-3-{2-(2,5-diphenylpyrazolo[1,5-c]pyrimidin-7-yl)hydrazono}indolin-2-ones 3 has been achieved by condensation of equimolar amounts of 7-hydrazino-2,5-diphenylpyrazolo[1,5-c]pyrimidine (1) and isatin (or isatin derivatives) 2 at room temperature. The (E)-products could be isomerized into corresponding the (Z)-3 isomers. Reactions of the latter fused heterocyclic hydrazones towards different electro-philic reagents yielded the corresponding 3-substituted derivatives 4-7. Dehydrative cyclisation of the hydrazones 3 using phosphorus oxychloride afforded the 2,5-diphenyl- indolo[2,3-e]pyrazolo[1',5':3",4"]pyrimido[2",1"-c][1,2,4] triazines 13. The polyfused heterocyclic ring system 13 underwent electrophilic substitution reactions at position 4 rather than at position 3. The 3-bromo isomer of 17 was prepared by a sequence of reactions starting from 2,5-diphenylpyrazolo[1,5-c]pyrimidine-7(6H)-thione (11). The orientation of the electrophilic attack was supported by spectroscopic and chemical evidence. Some of the synthesized compounds were found to possess slight to moderate activity against the microorganisms Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa.
authors.affiliation: Department of Chemistry, Faculty of Science, Alexandria University, Ibrahimia P.O. Box 426, Alexandria 21321, Egypt. prof.kf_atta@yahoo.com
authors.forename: Kamal F M
authors.initials: KF
authors.lastname: Atta
authors.forename: Omaima O M
authors.initials: OO
authors.lastname: Farahat
authors.forename: Somaya M
authors.initials: SM
authors.lastname: Ghobashy
authors.forename: Mohamed G
authors.initials: MG
authors.lastname: Marei
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D007536:Isomerism; D008826:Microbial Sensitivity Tests; D011720:Pyrazoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011743:Pyrimidines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D014227:Triazines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D007211:Indoles; D011720:Pyrazoles; D011743:Pyrimidines; D014227:Triazines