title: 1,2,4-Triazolo-quinazoline-thiones: Non-conventional synthetic approach, study of solvatochromism and antioxidant assessment.
abstract: A non-conventional methodology has been utilized for the synthesis of a series of 1,2,4-triazolo-quinazoline-thiones (2a-l). Here the reaction was carried out between 1,2,4-triazolo-quinazolinones (1a-l), in the presence of 1,4-dioxane. The mixture was irradiated under microwave (100W) for 7min to obtain targeted molecules (2a-l). All the synthesized molecules were confirmed by (1)H, (13)C NMR and HRMS. The solvatochromic property (absorption spectra) of compounds (2a-l) in solvents of different polarities was studied. The compounds (2a-l) were further subjected for their in vitro free radical screening using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and also screened for their in vitro anti-fungal property against Aspergillus flavus (A. flavus) and Aspergillus niger (A. niger). The results from free radical scavenging assay showed promising activity for compounds 2a, e-i, whereas compound 2d showed significant antioxidant activity when compared to ascorbic acid. In vitro anti-fungal study showed that the 1,2,4-triazolo-quinazoline-thiones (2a-l) had significant activity against A. flavus and A. niger compared with widely used antifungal agent Fluconazole.
authors.affiliation: Chemistry of Heterocycles & Natural Product Research Laboratory, Department of Chemistry, School of Advanced Sciences, VIT University, Vellore 632 014, Tamil Nadu, India.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Sompalle
authors.affiliation: Chemistry of Heterocycles & Natural Product Research Laboratory, Department of Chemistry, School of Advanced Sciences, VIT University, Vellore 632 014, Tamil Nadu, India. Electronic address: mohanaroopan.s@vit.ac.in.
authors.forename: Selvaraj Mohana
authors.initials: SM
authors.lastname: Roopan
authors.affiliation: Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Naif Abdullah
authors.initials: NA
authors.lastname: Al-Dhabi
authors.affiliation: Marine Biotechnology and Bioproducts Lab, School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu 632014, India.
authors.forename: K
authors.initials: K
authors.lastname: Suthindhiran
authors.affiliation: Marine Biotechnology and Bioproducts Lab, School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu 632014, India.
authors.forename: Gargi
authors.initials: G
authors.lastname: Sarkar
authors.affiliation: Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Mariadhas Valan
authors.initials: MV
authors.lastname: Arasu
mesh_terms: D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D001231:Aspergillus flavus / Q000187:drug effects; D001234:Aspergillus niger / Q000187:drug effects; D001713:Biphenyl Compounds / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D008826:Microbial Sensitivity Tests; D008872:Microwaves; D010851:Picrates / Q000737:chemistry; D011799:Quinazolines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D012997:Solvents / Q000737:chemistry; D013871:Thiones / Q000737:chemistry*
chemical_list: D000935:Antifungal Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D010851:Picrates; D011799:Quinazolines; D012997:Solvents; D013871:Thiones; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: 1,2,4-Triazolo-quinazoline-thiones; Free radical scavenging activity; Lawesson reagent; Organosulfur; UV–visible spectroscopy