Synthesis of novel dipodal-benzimidazole, benzoxazole and benzothiazole from cyanuric chloride: Structural, photophysical and antimicrobial studies

AbstractIn the present study, new benzimidazole, benzoxazole and benzothiazole derivatives were prepared and screened for antimicrobial activity. The structure of 4,4′-((6-(4-(diethylamino)phenyl)-1,3,5-triazine-2,4-diyl)bis(oxy))dibenzaldehyde (DIPOD) 5 was established from p-hydroxy benzaldehyde 4 and 4-(4,6-dichloro-1,3,5-triazin-2-yl)-N,N-diethylaniline 3. The reaction of DIPOD 5 with different o-phenylenediamine or o-amino phenol or o-amino thiophenol in ethanol gave benzimidazole, benzoxazole and benzothiazole 7. Novel heterocycles showed excellent broad-spectrum antimicrobial activity against bacterial strain (Escherichia coli, Staphylococcus aureus) and fungal strain (Candida albicans, Aspergillus niger) cultures. Activity data was compared with standard Streptomycin and Fluconazole drug. Photophysical and thermal properties of synthesized compounds were also studied

Near Infrared absorbing iron-complexed colorants for photovoltaic applications

Near Infrared absorbing colorants have several applications in the high technology area like heat ray blocking, energy conversion, and optical data storage. All these applications require that the colorants need to have broadband absorption extending up to the NIR region as well improved thermal stability. With the above objective in mind several analogues of pigment Green B (C.I. Acid Green 1) are prepared with improved thermal stability. These novel colorants are obtained by the incorporation of carboxamide group which imparts higher thermal stability. The spectral and TGA studies have shown that they are superior colorants, for application into photovoltaic cells.4 page(s

Synthesis and antimicrobial activity of novel 2-substituted benzimidazole, benzoxazole and benzothiazole derivatives

In an endeavor to find a new class of antimicrobial agents, a series of 2-(1H-benzimidazol-2-yl)-5-(diethylamino)phenol, 2-(1,3-benzoxazol-2-yl)-5-(diethylamino)phenol, 2-(1,3-benzothiazol-2-yl)-5-(diethylamino)phenol and their derivatives were synthesized starting from p-N,N-diethyl amino salicylaldehyde with different substituted o-phenylenediamine or o-aminophenol or o-aminothiophenol. The newly synthesized compounds were characterized by FT-IR, 1H NMR and LC–MS analysis. All compounds were evaluated for in vitro antibacterial activities against Escherichia coli and Staphylococcus aureus strains and in vitro antifungal activity against Candida albicans and Aspergillus niger strains by using serial dilution method. The antibacterial activities were expressed as the minimum inhibitory concentration (MIC) in μg/mL

Synthesis, photophysical properties of novel fluorescent metal complexes from 3-(1,3-benzoxazol-2-yl)naphthalen-2-ol, and their antimicrobial activities

A series of novel metal complexes containing metal atoms such as Zn, Co, Cu, Cd, Ni, Mg and Sn have been synthesized from 3-(1,3-benzoxazol-2-yl)naphthalen-2-ol. The synthesized ligand was well characterized by IR, 1H-NMR and mass spectrometry. The electrochemical properties were studied by cyclic voltammetric analysis. The synthesized complexes are fluorescent and absorb in the range of 317 to 323 nm while emit in the range of 371 to 416 nm with good quantum yield. All metal complexes show significant in vitro antibacterial activity against E. coli and S. aureus strains and in vitro antifungal activity against C. albicans and A. niger strains by using serial dilution method. The antibacterial activities were expressed as the minimum inhibitory concentration (MIC) in μg/mL

Synthesis of New ESIPT-Fluorescein: Photophysics of pH Sensitivity and Fluorescence

ESIPT-inspired benzimidazolyl substituted fluorescein dyes were synthesized. PH-sensitivity was determined by the photophysical property measured at a physiological possible pH range. Fluorescence quantum efficiency values were calculated independently at two different emissions. A rational relationship is defined between fluorescence quantum efficiency and calculated HOMO energy