Assessment of the Inhibitory Efficacy of a Thiazole Derivative as an Efficient Corrosion Inhibitor for Augmenting the Resistance of MS in Acidic Environments

Numerous thiazole compounds have been developed as cutting-edge inhibitors because of a rising fascination with using corrosion inhibitors (CIs) and preventative measures to prevent mild steel (MS) from deteriorating. In this study, the ability of a novel thiazole derivative, 2-hydrazono-3-methyl-2,3-dihydrobenzo[d]thiazole hydrochloride (HMDBT), to prevent corrosion of MS (MS) in HCl has been reconnoitered using various approaches, Viz. gravimetric analysis, electrochemical (EC) analysis, and different surface characterizations. With an inhibition efficiency (IE %) of 95.35%, the outcomes elucidate that HMDBT functions as a potent MS CI that is environmentally friendly and sustainable. The computed activation and thermodynamic factors were also employed to better explain the process underpinning the inhibiting tendency of HMDBT. According to the computed values, the HMDBT molecules physically and chemically adhered to the MS surface following the Langmuir model, generating a dense protective layer that may be associated with the presence of a benzene ring and heteroatoms (S & N) in the HMDBT architecture. Based on the findings of the EIS studies, an intensification in the CI's concentration from (50 →800) ppm is ushered by increases in polarization resistance (Rp) from (80.72, 354.31) Ω cm2, and attenuation in double-layer capacitance (Cdl) from (198.78 → 44.13) μF cm-2, respectively, confirming the inhibitory proficiency of HMDBT. The IE of the inhibitor was reported around 95.35% by weight loss measurement and 89.94% through EC measurement. Theoretical analysis including density functional theory (DFT) and molecular dynamics (MD) simulations were carried out to investigate the additional effects of HMDBT on the anticorrosion effectiveness and mechanism of inhibition. The theoretical parameters that were calculated provided important assistance in comprehending the inhibitory mechanism that the CI's moieties disclosed and are in strong concord with experimental methods. To create a "green" inhibitor system, the work presented here provided a potent technique to reduce corrosion by adding a potent new inhibitor.

Sulfonyl thioureas with a benzo[d]thiazole ring as dual acetylcholinesterase/butyrylcholinesterase and human monoamine oxidase A and B inhibitors: An in vitro and in silico study

A series of sulfonyl thioureas 6a-q containing a benzo[d]thiazole ring with an ester functional group was synthesized from corresponding substituted 2-aminobenzo[d]thiazoles 3a-q and p-toluenesulfonyl isothiocyanate. They had remarkable inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase (MAO)-A, and MAO-B. Among thioureas, several compounds had notable activity in the order of 6k > 6 h > 6c (AChE), 6j > 6g > 6k (BChE), 6k > 6g > 6f (MAO-A), and 6i > 6k > 6h (MAO-B). Compound 6k was an inhibitor of interest due to its potent or good activity against all studied enzymes, with IC50 values of 0.027 ± 0.008 μM (AChE), 0.043 ± 0.004 μM (BChE), 0.353 ± 0.01 μM (MAO-A), and 0.716 ± 0.02 μM (MAO-B). This inhibitory capacity was comparable to that of the reference drugs for each enzyme. Kinetic studies of two compounds with potential activity, 6k (against AChE) and 6j (against BChE), had shown that both 6k and 6j followed competitive-type enzyme inhibition, with Ki constants of 24.49 and 12.16 nM, respectively. Induced fit docking studies for enzymes 4EY7, 7BO4, 2BXR, and 2BYB showed active interactions between sulfonyl thioureas of benzo[d]thiazoles and the residues in the active pocket with ligands 6k, 6i, and 6j, respectively. The stability of the ligand-protein complexes while each ligand entered the active site of each enzyme (4EY7, 7BO4, 2BXR, or 2BYB) was confirmed by molecular dynamics simulations.

Recent advances in the synthesis of new benzothiazole based anti-tubercular compounds

This review highlights the recent synthetic developments of benzothiazole based anti-tubercular compounds and their in vitro and in vivo activity. The inhibitory concentrations of the newly synthesized molecules were compared with the standard reference drugs. The better inhibition potency was found in new benzothiazole derivatives against M. tuberculosis. Synthesis of benzothiazole derivatives was achieved through various synthetic pathways including diazo-coupling, Knoevenagel condensation, Biginelli reaction, molecular hybridization techniques, microwave irradiation, one-pot multicomponent reactions etc. Other than recent synthetic developments, mechanism of resistance of anti-TB drugs is also incorporated in this review. Structure activity relationships of the new benzothiazole derivatives along with the molecular docking studies of selected compounds have been discussed against the target DprE1 in search of a potent inhibitor with enhanced anti-tubercular activity.

A Novel PIFA/KOH Promoted Approach to Synthesize C2-arylacylated Benzothiazoles as Potential Drug Scaffolds

To discover an efficient and convenient method to synthesize C2-arylacylated benzothiazoles as potential drug scaffolds, a novel [bis(trifluoroacetoxy)iodo]benzene(PIFA)/KOH synergistically promoted direct ring-opening C2-arylacylation reaction of 2H-benzothiazoles with aryl methyl ketones has been developed. Various substrates were tolerated under optimized conditions affording the C2-arylacylation products in 70-95% yields for 38 examples. A plausible mechanism was also proposed based on a series of controlled experiments.

Aminothiazole-Linked Metal Chelates: Synthesis, Density Functional Theory, and Antimicrobial Studies with Antioxidant Correlations

During the current study, the new aminothiazole Schiff base ligands (S1 ) and (S2 ) were designed by reacting 1,3-thiazol-2-amine and 6-ethoxy-1,3-benzothiazole-2-amine separately with 3-methoxy-2-hydroxybenzaldehyde in good yields (68-73%). The ligands were characterized through various analytical, physical, and spectroscopic (FT-IR, UV-Vis, 1H and 13C NMR, and MS) methods. The ligands were exploited in lieu of chelation with bivalent metal (cobalt, nickel, copper, and zinc) chlorides in a 1:2 (M:L) ratio. The spectral (UV-Vis, FT-IR, and MS), as well as magnetic, results suggested their octahedral geometry. The theoretically optimized geometrical structures were examined using the M06/6-311G+(d,p) function of density function theory. Their bioactive nature was designated by global reactivity parameters containing a high hardness (η) value of 1.34 eV and a lower softness (σ) value of 0.37 eV. Different microbial species were verified for their potency (in vitro), revealing a strong action. The Gram-positive Micrococcus luteus and Gram-negative Escherichia coli gave the highest activities of 20 and 21 mm for compounds (8) and (7), respectively. The antifungal activity against the Aspergillus niger and Aspergillus terreus species gave the highest activities of 20 and 18 mm for compounds (7) and (6), respectively. The antioxidant activity, evaluated as DPPH and ferric reducing power, gave the highest inhibition (%) as 72.0 ± 0.11% (IC50 = 144 ± 0.11 μL) and 66.3% (IC50 = 132 ± 0.11 μL) for compounds (3) and (8), respectively. All metal complexes were found to be more biocompatible than free ligands due to their chelation phenomenon. The energies of LUMOs had a link with their activities.

Recent developments in mitogen activated protein kinase inhibitors as potential anticancer agents

The mitogen activated protein kinase (MAPK) belongs to group of kinase that links the extracellular stimuli to intracellular response. The MAPK signalling pathway (RAS-RAF-MEK-ERK) involved in different pathological conditions like cancer, caused due to genetic or any other factor such as physical or environmental. Many studies have been conducted on the pathological view of MAPK cascade and its associated element like RAS, RAF, MEK, ERK or its isoforms, and still the research is going on particularly with respect to its activation, regulation and inhibition. The MAPK signalling pathway has become the area of research to identify new target for the management of cancer. A number of heterocyclics are key to fight with the cancer associated with these enzymes thus give some hope in the management of cancer by inhibiting MAPK cascade. In the present article, we have focussed on MAPK signalling pathway and role of different heterocyclic scaffolds bearing nitrogen, sulphur and oxygen and about their potential to block MAPK signalling pathway. The heterocyclics are gaining importance due to high potency and selectivity with less off-target effects against different targets involved in the MAPK signalling pathway. We have tried to cover recent advancements in the MAPK signalling pathway inhibitors with an aim to get better understanding of the mechanism of action of the compounds. Several compounds in the preclinical and clinical studies have been thoroughly dealt with. In addition to the synthetic compounds, a significant number of natural products containing heterocyclic moieties as MAPK signalling pathway inhibitors have been put together. The structure activity relationship along with docking studies have been discussed to apprehend the mechanistic studies of various compounds that will ultimately help to design and develop more MAPK signalling pathway inhibitors.