No abstract

In this work, graphene oxide (GO) is synthesized via chemical method (improved method) and reduced grapheneoxide(rGO) using thermal treatment. The GO and rGO thin films were coated on a glass substrate by using drop casting method. The GO and rGO thin film were characterized by scanningelectronmicroscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) to make sure the morphological and optical characteristics of the thin film. In addition, the electrical studies were performed by current-voltage (I-V) characteristic. The rGO thin film displays higher conductivity in comparison with GO which is 4.12 x 10-5S/cm, and also affected the morphological (SEM) and optical properties (FTIR). Morphological and optical data confirms that rGO losses the oxygen groups compare to GO.

Titanium dioxide (TiO 2) thin films were deposited on fluorine tin oxide (FTO) coated glass substrate using spin-coating techniques and as-deposited films were sensitized with various dyes. A series of azo derivatives (2, 5a-b) having different structures were successfully prepared through the process of the azo coupling reaction. KAZO 6 was successfully synthesized by esterification of kojic acid obtained from sago waste with azo 5a. These azo dye were examined using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) to obtain the vertical excitation, electron distribution, energy levels, band gap, and light-harvesting efficiency in the ground and excited state. The obtained values exhibited a good correlation with the experimental values. Efficiency enhancement was reported by the incorporation of KAZO 6 with curcumin extracted from turmeric. Spectroscopy and optical properties of synthesized dyes were characterized using CHNS elemental analysis, FTIR, 1 H NMR, 13 C NMR, and UV-Vis spectroscopies. KAZO 6 displayed an efficiency of 1.59% compared to azo derivatives 0.13-1.12%. The efficiency of KAZO 6 enhanced from 1.59 to 1.74% with the incorporation of turmeric dye.

Bacterial diseases cause hazardous infections due to the occurrence of bacterial resistance. Drugs production to cure bacterial resistance from natural sources has become ineffective to execute the resisted bacteria due to the unsuitable binding interaction of active sites with the receptors. Drug link to natural products moieties such as chalcones and pyrazolines, which originated from plants extracts, has become attractive among researchers due to its significant pharmaceutical moiety. In this study a series of chalcone derivatives (1 a–d) has been synthesized via Claisen‐Schmidt condensation, followed by cyclization to form pyrazolines (2 a–d, 3 a–d). Fischer esterification of pyrazolines formed 4 a–d in moderate to good yield (42.91‐88.23 %). Antimicrobial activities of all the synthesized compounds were evaluated against Escherichia coli and Staphylococcus aureus via disc diffusion. Among all compounds, pyrazolines 3 c and 3 d showed the highest zone of inhibition (17 mm) compared to 1 a‐d (5‐11 mm) and standard ampicillin (11 mm). The exchange of α, β‐unsaturated carbonyl showed phenomenal increment in the biological activities. Structure activity relationship of 1 a, 1 d, 3 a and 3 d was analyzed via molecular docking of N‐terminal domain having deoxyribonucleic acid (DNA) binding protein (4pql) with excellent binding energy of −6.2, −6.6, −7.1 and −7.2 kcal/mol, respectively. This work is significant in designing new drugs with keto‐exchange relationship for medicinal industry.

In this work, a new organic compound (K-Azo) was introduced to enhance the electrical and optical performance of graphene oxide (GO) and reduced GO (rGO) nanostructured films. The improved and modified chemical vapour method was employed for the synthesis of GO and rGO. The photophysical characterization of thin films was performed by applying analytical techniques including X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, ultraviolet-visible, and Raman spectroscopy. The electrical properties (I-V characteristic) of GO and rGO thin films displayed higher conductivity which was 4.07 × 10 −7 and 1.10 × 10 −3 S/cm, respectively in the presence of organic sensitizer. However, GO and rGO thin films showed 9.91 × 10 −7 and 6.17 × 10 −4 S/cm, respectively in the absence of K-Azo sensitizer.Optical and electrical investigations indicated that the characteristics of GO and rGO were improved due to the presence of organic sensitizer. The longrange π-electron delocalization in organic sensitizer contributed to higher conductivity for potential photovoltaic solar cell applications.

Epoxy chalcone is a heterocyclic molecule and an important precursor for the synthesis of biologically active compounds. This mini-review is elucidating the synthetic strategies of chalcone epoxide via one pot and two pot routes including nature of reactants, nature of catalyst and variety of catalyst to improve yield of desired product, biological applications and advantages and drawbacks of these synthetic strategies. One pot route has wide variety of reactants and efficient one is the condensation of aldehyde and ketone. However, two pot route is consisted of chalcone synthesis preceding to epoxy chalcone. The synthetic routes for the preparation of epoxy chalcone and the usage as a precursor for the synthesis of various organic molecules with biological application is comprehensively discussed. This review is outstanding in organic chemistry and pharmaceutical industries to produce new molecules with various applications. Graphic AbstractO O

No abstract

The evolution of drug resistant bacteria has now becoming a major concern in the search for new antibacterial agent. Ongoing interest has also developing to find a new class of compounds with antioxidant properties. Herein, a series of hydroxylated chalcones 1a-g and aspirin-chalcone derivatives 2a-g were successfully synthesised for antibacterial and antioxidant properties. Chalcones 1a-g were prepared by Claisen-Schmidt condensation of 4-hydroxyacetophenone and benzaldehyde derivatives, while 2a-g were synthesised via esterification of aspirin with 1a-g. All the synthesised compounds were elucidated using CHNS elemental analysis, FTIR, 1H and 13C NMR spectroscopy, and X-ray crystallography. All compounds were evaluated for antibacterial assay via disc diffusion method and antioxidant assay using stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). Only 1a showed moderate activity against Escherichia coli, while 1b-g and 2a-g showed no inhibition against E. coli and Staphylococcus aureus in comparison ampicillin as standard antibiotic. Compounds 1b-g and 2a-g having various substituents contributed to bulky molecular structures and caused difficult penetration into the cell membrane thus, unable to inhibit the bacterial growth. Compounds 1a-g and 2a-g also displayed poor antioxidant properties on DPPH in comparison to ascorbic acid due to low phenolic pharmacophore. The formation of bulky structures for 2a-g have hindered the antioxidant properties compared to 1a-g.