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Three Schiff bases were synthesised by the condensation reaction between 2-napthaldehyde and aromatic amines to afford (E)-N-mesityl-1-(naphthalen-2-yl)methanimine (L1), (E)-N-(2,6-dimethylphenyl)-1-(naphthalen-2-yl)methanimine (L2) and (E)-N-(2,6-diisopropylphenyl)-1-(naphthalen-2-yl)methanimine (L3). The synthesised compounds were characterised using UV–visible, NMR (13C & 1H), and Fourier transform infrared spectroscopic methods while their purity was ascertained by elemental analysis. Structural analysis revealed that the naphthalene ring is almost coplanar with the imine functional group as evident by C1–C10–C11–N1 torsion angles of 176.4(2)° and 179.4(1)° in L2 and L3, respectively. Of all the various intermolecular contacts, H⋯H interactions contributed mostly towards the Hirshfeld surfaces of both L2 (58.7 %) and L3 (69.7 %). Quantum chemical descriptors of L1 - L3 were determined using Density Functional Theory (DFT) and the results obtained showed that the energy band gap (ΔE) for L1, L2 and L3 are 3.872, 4.023 and 4.004 eV respectively. The antidiabetic potential of the three compounds were studied using α-amylase and α-glucosidase assay. Compound L1 showed very promising antidiabetic activities with IC50 values of 58.85 μg/mL and 57.60 μg/mL while the reference drug (Acarbose) had 405.84 μg/mL and 35.69 μg/mL for α-amylase and α-glucosidase respectively. In-silico studies showed that L1 docking score as well as binding energies are higher than that of acarbose, which are recognized inhibitors of α-amylase together with α-glucosidase. Further insight from the RMSF, RMSD and RoG analysis predicted that, throughout the simulation L1 showcased evident influence on the structural stability of α-amylase. The antioxidant potential of the compounds was carried out using nitric oxide (NO), ferric reducing ability power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. The compounds exhibited good to fairly antioxidant properties with L1 as well as L3 having IC50 values of 70.91 and 91.21 μg/mL respectively for NO scavenging activities assay, which comparatively outshined acarbose (reference drug) with IC50 value of 109.95 μg/mL. Pharmacology and pharmacokinetics approximations of L1 – L3 showed minimal violation of Lipinski's Ro5 and this projects them to be less toxic and orally bioavailable as potential templates for the design of therapeutics with antioxidant and antidiabetic activities.

The utilization of fibrous prunus dulcis seed shell powder (UPDSSP) and the phosphate-modified derivative (P-MPDSS) for the abstraction of Pb2+ was tested. The Fourier transform infrared (FTIR), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), energy-dispersive X-ray (EDX), and the physicochemical characterizations revealed desirable characteristics of the adsorbents for efficient Pb(II) uptake. The FTIR of UPDSSP and P-MPDSS showed several functionality groups on the adsorbents. SEM morphology revealed high porosity surface structure of both adsorbents, while BET measurements showed an increase in surface area from 5.84 m2/g to 11.32 m2/g after phosphate modification. The modified adsorbent showed higher Pb(II) uptake than UPDSSP at variations of temperature, time, pH, metal concentration, and material dosage. pH 5.0 was optimum for Pb(II) adsorption and equilibrium was reached at 90 min on UPDSSP and P-MPDSS. The Freundlich isotherm presented the best fit (R2 > 0.991) than the Langmuir and Dubinin-Raduskkevich models. The pseudo-second-order gave the best fit (R2 > 0.971) than the pseudo-first-order and intraparticle diffusion kinetic equations. Thermodynamics showed endothermic, spontaneous, and physical adsorption of Pb(II) ions onto the adsorbents. The adsorbents showed good potentials for regeneration and reuse. The results revealed UPDSSP and P-MPDSS as viable materials for the decontamination of Pb polluted water.

Herein, nickel oxide (NiO) nanosheets coated with carbon were successfully synthesized on three dimensional all-carbon-frameworks through hydrothermal and annealing process. The as-prepared GPG/NiO/C achieved a high areal capacity of 24.55 mAh cm−2 @ 2.0 mA cm−2 as anode material for lithium-ion batteries (LIBs). In situ Raman analysis was employed to study the lithium storage mechanism of the GPG/NiO/C electrode. This work opens more opportunity for achieving high areal capacity electrode for energy storage devices.

Melon seed shells (MSS) are a hazard to the environment as they host disease vectors. To alleviate the effect, we explored melon seed shells (MSS) as a new source of nanocrystalline cellulose (NCC) with reducing- and stabilizing capacity for the synthesis of silver nanoparticles (AgNPs). The isolation of NCC from discarded MSS served the dual purpose of a reducing- and stabilizing agent in the synthesis of AgNPs. The isolated needle-like crystals (MSS-NCC) had a mean length 204 nm, width 7 nm and aspect ratio 30. The NCC had crystallinity index of 94% with surface rich in –OH and –COOH functionality. The obtained AgNPs covered the surface of the MSS-NCC and catalysed the reduction of nitrobenzene to aniline using NaBH4. The process of the reduction monitored via UV-vis spectroscopy was completed within 12 min. with a rate constant 0.04 min−1 as revealed by the kinetic study.

We report on the design, synthesis, and characterization of the first silver hydride clusters solely protected and stabilized by dithiophosphonate ligands and their application for the in situ generation of silver nanoparticles towards the catalytic reduction of 4-nitrophenol in an aqueous system. The synthesis of the silver monohydride cluster involves the incorporation of an interstitial hydride using sodium borohydride. Poly-nuclear magnetic resonance and mass spectrometry were used to establish the structural properties. The structural properties were then confirmed with a single-crystal X-ray diffraction analysis, which showed a distorted tetracapped tetrahedron core with one hydride ion encapsulated within the core of the silver framework. Additionally, the synthesized heptanuclear silver hydride was utilized as a precursor for the in situ generation of silver nanoparticles, which simultaneously catalyzed the reduction of 4-nitrophenol. The mechanism of the catalytic activity was investigated by first synthesizing AgNPs, which was subsequently used as a catalyst. The kinetic study showed that the pseudo-first constant obtained using the cluster (2.43 × 10−2 s−1) was higher than that obtained using the synthesized AgNPs (2.43 × 10−2 s−1). This indicated that the silver monohydride cluster was more active owing to the release of the encapsulated hydride ion and greater reaction surface prior to aggregation.

Developing new, more effective antibiotics against resistant Mycobacterium tuberculosis that inhibit its essential proteins is an appealing strategy for combating the global tuberculosis (TB) epidemic. Finding a compound that can target a particular cavity in a protein and interrupt its enzymatic activity is the crucial objective of drug design and discovery. Such a compound is then subjected to different tests, including clinical trials, to study its effectiveness against the pathogen in the host. In recent times, new techniques, which involve computational and analytical methods, enhanced the chances of drug development, as opposed to traditional drug design methods, which are laborious and time-consuming. The computational techniques in drug design have been improved with a new generation of software used to develop and optimize active compounds that can be used in future chemotherapeutic development to combat global tuberculosis resistance. This review provides an overview of the evolution of tuberculosis resistance, existing drug management, and the design of new anti-tuberculosis drugs developed based on the contributions of computational techniques. Also, we show an appraisal of available software and databases on computational drug design with an insight into the application of this software and databases in the development of anti-tubercular drugs. The review features a perspective involving machine learning, artificial intelligence, quantum computing, and CRISPR combination with available computational techniques as a prospective pathway to design new anti-tubercular drugs to combat resistant tuberculosis.