title: Silicon-containing bis-azomethines: synthesis, structural characterization, evaluation of the photophysical properties and biological activity.
abstract: A new diamine, (dimethylsilanediyl)bis(methylene)bis(4-aminobenzoate) (1), containing dimethylsilane spacer, was prepared by the condensation of p-aminobenzoic acid with bis(chloromethyl)dimethylsilane. This was subsequently reacted with salicylaldehyde, 3-hydroxy-salicylaldehyde, and 3-methoxy-salicyladehyde, when corresponding Schiff bases (E)-(dimethylsilanediyl)bis(methylene)bis(4-((E)-(2-hydroxybenzilidene)amino)benzoate (2), (E)-(dimethylsilanediyl)bis(methylene)bis(4-((E)-(2-hydroxybenzilidene)amino)benzoate (3), and (E)-(dimethylsilanediyl)bis(methylene) bis(4-((E)-(2-hydroxy-3-methoxybenzilidene)amino)benzoate (4), respectively were formed. All the obtained compounds were structurally characterized by spectral (FT-IR, (1)HNMR, (13)CNMR) analyses and single crystal X-ray diffraction. Photophysical studies revealed that the new prepared Schiff bases are good UV light absorbing and fluorescent materials. Thus, they exhibit strong UV/Vis-absorption at 250-400nm and violet or orange emission, in sensitive dependence on the polarity of the solvents and the nature of the substituent (H, OH and OCH3) at the aromatic ring. The antimicrobial activity of these compounds was first studied in vitro by the disk diffusion assay against two species of bacteria and three fungi. The minimum inhibitory concentration was then determined with the reference of standard compounds. The results displayed that Schiff bases 3 and 4 having hydroxy- and methoxy-substituents on the aromatic ring were better inhibitors of both types of species (bacteria and fungi) than standard compounds, Caspofungin and Kanamycin.
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Gr. Ghica Voda 41A, 700487 Iaşi, Romania.
authors.forename: Mirela-Fernanada
authors.initials: MF
authors.lastname: Zaltariov
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Gr. Ghica Voda 41A, 700487 Iaşi, Romania.
authors.forename: Angelica
authors.initials: A
authors.lastname: Vlad
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Gr. Ghica Voda 41A, 700487 Iaşi, Romania. Electronic address: mcazacu@icmpp.ro.
authors.forename: Maria
authors.initials: M
authors.lastname: Cazacu
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Gr. Ghica Voda 41A, 700487 Iaşi, Romania.
authors.forename: Mihaela
authors.initials: M
authors.lastname: Avadanei
authors.affiliation: Metropolitan Center of Research TABOR, The Metropolitanate of Moldavia and Bukovina, Closca 9, 700066 Iaşi, Romania.
authors.forename: Nicoleta
authors.initials: N
authors.lastname: Vornicu
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Gr. Ghica Voda 41A, 700487 Iaşi, Romania.
authors.forename: Mihaela
authors.initials: M
authors.lastname: Balan
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Gr. Ghica Voda 41A, 700487 Iaşi, Romania.
authors.forename: Sergiu
authors.initials: S
authors.lastname: Shova
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D001391:Azo Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001424:Bacterial Infections / Q000188:drug therapy; D018360:Crystallography, X-Ray; D003959:Diamines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D005658:Fungi / Q000187:drug effects; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009181:Mycoses / Q000188:drug therapy; D017646:Organosilicon Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D012821:Silanes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D017550:Spectroscopy, Fourier Transform Infrared; D013882:Thiosemicarbazones / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*
chemical_list: D000447:Aldehydes; D000890:Anti-Infective Agents; D001391:Azo Compounds; D003959:Diamines; D017646:Organosilicon Compounds; D012821:Silanes; D013882:Thiosemicarbazones; C512188:azomethine; C013243:salicylaldehyde
keywords: Amine; Azomethine; Biological activity; Photophysical properties; Structural characterization