Abstract:
Background: Synthesis and biological
investigations of 3-benzylideneindolin-2-ones has stirred interest in
pharmaceutical field due to its privileged
scaffold oxindole. These oxindole
derivatives have a broad spectrum of
biological activities including anti-cancer,
anti-viral, anti-bacterial, anti-oxidant and
anti-inflammatory. Microwave-assisted
organic reactions in solvent-free
conditions has many advantages over
conventional methods such as higher
atom- economy, E-factor and product
purity.
Objectives: Microwave-assisted solventfree synthesis of 3-benzylidineindolin-2-one and investigation of anti-fungal and
anti-oxidant activities.
Methods: Oxindole and benzaldehyde is
thoroughly mixed with (3-Aminopropyl)
triethoxysilane (APTES) functionalized
silica catalyst and irradiatedinside the
modified microwave oven for 12 minutes.
After completion of the reaction the
resulting products wereextracted to a
mixture of ethanol, acetone and ethyl
acetate (1: 1: 1: v/v) and subsequently
purified by column chromatography.
Resulted product was characterized by
Nuclear Magnetic Resonance
spectroscopy (1H NMR and13C NMR),
Fourier-Transform Infrared spectroscopy
(FTIR) and melting point analysis. The
compound was tested for in-vitro antifungal activity against Candida albicans(ATCC 10231) and Candida krusei (ATCC
6258) using welldiffusion assay and broth
micro dilution assay. Anti-oxidant activity
of the compound was investigated using
2,2-azino-bis(3-ethylbenzothiazoline-6-
sulfonic acid (ABTS) assay
Results: Melting point of the synthesized
1H NMR, 13C NMR
and FTIR data confirms theformation of
targeted 3-Benzylideneindolin-2-ones and
has an agreement with the reported data
in the literature. Themean zones of
inhibition (ZOI) of the compound and the
positive control miconazole against
Candida albicansandCandidakrusei were
20.0 mm, 18.33 mm and 14.6 mm and
22.6 mm respectively. Both minimum
inhibitoryconcentration and minimum
fungicidal concentration of the compound
against Candida albicans and Candida
krusei
respectively. The concentration at 50%
inhibition (IC-50) of the compound was
0.2mg/mL