Anticancer activity of Mannich bases: a review of recent literature

This report summarizes the latest published data on the antiproliferative action and cytotoxic activity of Mannich bases, a structurally heterogeneous category of chemical entities that includes compounds which are synthesized via the grafting of an aminomethyl function onto diverse substrates by means of the Mannich reaction. The present overview of the topic is an update to the information assembled in a previously published review that covered the literature up to 2014.

Synthesis, characterisation, biological evaluation and in silico studies of sulphonamide Schiff bases

Sulphonamides are biologically important compounds with low toxicity, many bioactivities and cost-effectiveness. Eight sulphonamide derivatives were synthesised and characterised by FT-IR, ¹³C NMR, ¹H NMR, LC-MS and elemental analysis. Their inhibitory effect on AChE, and carbonic anhydrase I and II enzyme activities was investigated. Their antioxidant activity was determined using different bioanalytical assays such as radical scavenging tests with ABTS^•+, and DPPH^•+ as well as metal-reducing abilities with CUPRAC, and FRAP assays. All compounds showed satisfactory enzyme inhibitory potency in nanomolar concentrations against AChE and CA isoforms with K_I values ranging from 10.14 ± 0.03 to 100.58 ± 1.90 nM. Amine group containing derivatives showed high metal reduction activity and about 70% ABTS radical scavenging activity. Due to their antioxidant activity and AChE inhibition, these novel compounds may be considered as leads for investigations in neurodegenerative diseases.

Design, synthesis and biological evaluation of novel pyxinol derivatives with anti-heart failure activity

Heart failure (HF) is an important and leading cause of substantial morbidity and mortality globally. The angiotensin-converting enzymatic (ACE) is the causative source for congestive heart failure. Natural products and its derivatives play a vital role in drug discovery and development owing to their efficacy and low toxicity. Pyxinol is a potent natural agent for cardiovascular disease. Thus we investigated the effect on ACE and HF of pyxinol derivatives. We designed and synthesized 32 novel fatty acid ester derivatives of pyxinol via esterification. Among them, compounds 2e (IC₅₀=105 nM) and 3b (IC₅₀=114 nM) displayed excellent ACE inhibitory activity in vitro, and exhibited non-toxic to H9c2 cells. The interactions between ACE and compounds were predicted by molecular docking respectively. In verapamil-induced zebrafish HF model, the activity assay showed that these two derivatives could improve cardiovascular physiological indexes including heart beats, venous congestion, heart dilation, cardiac output, ejection fraction and fractional shortening in a dose-dependent manner. A UPLC-QTOF-MS-based serum metabolomics approach was applied to explore the latent mechanism. A total of 25 differentiated metabolites and 8 perturbed metabolic pathways were identified. These results indicated that pyxinol fatty acid ester derivatives 2e and 3b might be considered as potent drug candidates against heart failure and deserved further research and development.

Novel quinazolin-sulfonamid derivatives: synthesis, characterization, biological evaluation, and molecular docking studies

In the design of novel drugs, the formation of hybrid molecules via the combination of several pharmacophores can give rise to compounds with interesting biochemical profiles. A series of novel quinazolin-sulfonamid derivatives (9a-m) were synthesized, characterized and evaluated for their in vitro antidiabetic, anticholinergics, and antiepileptic activity. These synthesized novel quinazolin-sulfonamid derivatives (9a-m) were found to be effective inhibitor molecules for the α-glycosidase, human carbonic anhydrase I and II (hCA I and hCA II), butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) enzyme, with Ki values in the range of 100.62 ± 13.68-327.94 ± 58.21 nM for α-glycosidase, 1.03 ± 0.11-14.87 ± 2.63 nM for hCA I, 1.83 ± 0.24-15.86 ± 2.57 nM for hCA II, 30.12 ± 3.81-102.16 ± 13.87 nM for BChE, and 26.16 ± 3.63-88.52 ± 20.11 nM for AChE, respectively. In the last step, molecular docking calculations were made to compare biological activities of molecules against enzymes which are achethylcholinesterase, butyrylcholinesterase and α-glycosidase.Communicated by Ramaswamy H. Sarma.

Evaluation of parent and nano-encapsulated terbium(III) complex toward its photoluminescence properties, FS-DNA, BSA binding affinity, and biological applications

BACKGROUND

There is a crucial need for finding and developing new compounds as the anticancer and antimicrobial agents with better activity, specific target, and less toxic side effects.

OBJECTIVES

Base on the potential anticancer properties of lanthanide complexes, in the paper, the biological applications of terbium (Tb) complex, containing 2,9-dimethyl- 1,10-phenanthroline (Me2Phen) such as anticancer, antimicrobial, DNA cleavage ability, the interaction with FS-DNA (Fish-Salmon DNA) and BSA (Bovine Serum Albumin) was examined.

METHODS

The interaction of Tb-complex with BSA and DNA was studied by emission spectroscopy, absorption titration, viscosity measurement, CD spectroscopy, competitive experiments, and docking calculation. Also, the ability of this complex to cleave DNA was reported by gel electrophoresis. Tb-complex was concurrently screened for its antibacterial activities by different methods. Besides, the nanocarriers of Tb-complex (lipid nanoencapsulation (LNEP) and the starch nanoencapsulation (SNEP)), as active anticancer candidates, were prepared. MTT technique was applied to measure the antitumor properties of these compounds on human cancer cell lines.

RESULTS

The experimental and docking results suggest significant binding between DNA as well as BSA with terbium-complex. Besides, groove binding plays the main role in the binding of this compound with DNA and BSA. The competitive experiment with hemin demonstrated that the terbium complex was bound at site III of BSA, which was confirmed by the docking study. Also, Tb-complex was concurrently screened for its DNA cleavage, antimicrobial, and anticancer activities. The anticancer properties of LNEP and SNEP are more than the terbium compound.

CONCLUSIONS

Tb-complex can bond to DNA/BSA with high binding affinity. Base on biological applications of Tb-complex, it can be concluded that this complex and its nanocarriers can suggest as novel anticancer, antimicrobial candidates.

Inhibition profiles of Voriconazole against acetylcholinesterase, α-glycosidase, and human carbonic anhydrase I and II isoenzymes

In this work, the inhibitory activity of Voriconazole was measured against some metabolic enzymes, including human carbonic anhydrase (hCA) I and II isoenzymes, acetylcholinesterase (AChE), and α-glycosidase; the results were compared with standard compounds including acetazolamide, tacrine, and acarbose. Half maximal inhibition concentration (IC₅₀ ) values were obtained from the enzyme activity (%)-[Voriconazole] graphs, whereas K_i values were calculated from the Lineweaver-Burk graphs. According to the results, the IC₅₀ value of Voriconazole was 40.77 nM for α-glycosidase, while the mean inhibition constant (K_i ) value was 17.47 ± 1.51 nM for α-glycosidase. The results make an important contribution to drug design and have pharmacological applications. In addition, the Voriconazole compound demonstrated excellent inhibitory effects against AChE and hCA isoforms I and II. Voriconazole had K_i values of 29.13 ± 3.57 nM against hCA I, 15.92 ± 1.90 nM against hCA II, and 10.50 ± 2.46 nM against AChE.

The effects of zingerone against vancomycin-induced lung, liver, kidney and testis toxicity in rats: The behavior of some metabolic enzymes

In this study, it was demonstrated the ameliorative effect of zingerone (ZO) (25 and 50 mg/kg body weight) against vancomycin (VCM) (200 mg/kg body weight) administered to rats on some metabolic enzymes' activities in the lung, liver, kidney, and testis tissues of rats. Forty-two rats were divided into six groups as follows: control, ZO-25, ZO-50, VCM, VCM + ZO-25, and VCM + ZO-50. α-Glycosidase, butyrylcholinesterase, aldose reductase, acetylcholinesterase, paraoxonase-1, and carbonic anhydrase enzyme activities were significantly (P < .05) decreased in VCM group when compared with the control group. ZO, supplied with VCM, significantly activated some of these enzyme in all tissues. The results of this study showed that ZO regulates abnormal increases and decreases in VCM-induced metabolic enzyme activities in all tissues.

Synthesis and biological evaluation of bromophenol derivatives with cyclopropyl moiety: Ring opening of cyclopropane with monoester

Trans-(1R*,2R*,3R*)-Ethyl 2-(3,4-dimethoxyphenyl)-3-methylcyclopropane-1-carboxylate (6) and its cis isomer 7 were obtained from the reaction of the methyl isoeugenol (5) with ethyl diazoacetate. The reduction and bromination reactions of the ester 6 and 7 together with the hydrolysis of all esters were carried out. Opening ring of cyclopropane was observed in the reaction of 7 with bromine. The opening of cyclopropane ring with COOR and synthesis of esters, alcohols and acids (6-26) are new. These obtained bromophenol derivatives (6-26) were effective inhibitors of the cytosolic carbonic anhydrase I and II isoforms (hCA I and II) and acetylcholinesterase (AChE) enzymes with Ki values in the range of 7.8 ± 0.9-58.3 ± 10.3 nM for hCA I, 43.1 ± 16.7-150.2 ± 24.1 nM for hCA II, and 159.6 ± 21.9-924.2 ± 104.8 nM for AChE, respectively. Acetylcholinesterase inhibitors are the most popular drugs applied in the treatment of diseases such as Alzheimer's disease, Parkinson's disease, senile dementia, and ataxia, among others.

Synthesis, characterization, molecular docking and biological activities of novel pyrazoline derivatives

In this study, synthesis of ethyl 2-((4-bromophenyl)diazenyl)-3-oxo-phenylpropanoate 1 was carried out and a series of new 3H-pyrazol-3-ones (P1-7) were synthesized from 1 as well as various hydrazines. The obtained yields of the synthesized compounds were moderate (40-70%) and these compounds were confirmed by spectral data. These novel pyrazoline derivatives were effective inhibitor compounds of the human carbonic anhydrase I and II isozymes (hCAs I and II) and of the acetylcholinesterase (AChE) enzyme, with K_i values in the range of 17.4-40.7 nM for hCA I, 16.1-55.2 nM for hCA II, and 48.2-84.1 nM for AChE. In silico studies were performed on the compounds inhibiting hCA I, hCA II, and AChE receptors. On the basis of the findings, the inhibition profile of the new pyrazoline compounds at the receptors was determined.

In vitro cytotoxic and in vivo antitumoral activities of some aminomethyl derivatives of 2,4-dihydro-3H-1,2,4-triazole-3-thiones-Evaluation of their acetylcholinesterase and carbonic anhydrase enzymes inhibition profiles

The 1,2,4-triazole and its derivatives were reported to exhibit various pharmacological activities such as antimicrobial, analgesic, anti-inflammatory, antitumoural, cytotoxic, and antioxidant properties. In this study, a series of triazole compounds (M1-M10) were evaluated for some biological activities. In vitro qualifications of these compounds on acetylcholinesterase (AChE) and human carbonic anhydrase enzyme activities were performed. Also, their antitumoral activities in human colon cancer (HT29) cell line cultures were examined. In addition, colon cancer experimentation was induced in rats by an in vivo method, and the in vivo anticancer effects of triazole derivatives were investigated. Also, the effects of these derivatives in levels of antioxidant vitamin A, vitamin E, and MDA were studied in rat liver and blood samples. Most of the compounds were found to exhibit significant antioxidant and antitumoral activities. All the compounds had cytotoxic activities on HT29 cell lines with their IC50 values lower than 10 µM concentrations. The low IC 50 values of the compounds are M1 (3.88 µM), M2 (2.18 µM), M3 (4.2 µM), M4 (2.58 µM), M5 (2.88 µM), M6 (2.37 µM), M7 (3.49 µM), M8 (4.01 µM), M9 (8.90 µM), and M10 (3.12 µM).

Synthesis, characterization, crystal structure of the coordination polymer Zn(II) with thiosemicarbazone of glyoxalic acid and their inhibitory properties against some metabolic enzymes

A new coordination polymer Zn(II) with thiosemicarbazone glyoxalic acid H₂GAT was obtained in this study. According to the X-ray diffraction data, the coordination of the Zn(II) ion is carried out by one sulfur atom, in the thiol form, one nitrogen atom of the azomethine group and two oxygen atoms of the carboxylate groups, one of which belongs to neighbouring complex molecule. The oxygen atom of the water molecule completes Zn(II) ion environment to a distorted square-pyramidal structure. The binding of the monomer complex into polimer occurs through the bridge oxygen atom of carboxylate group. This complex is effective inhibitor of the α-glycosidase, butyrylcholinesterase (BChE), cytosolic carbonic anhydrase I and II isoforms (hCA I and II), and acetylcholinesterase enzymes (AChE) enzymes with Ki values of 1.45 ± 0.23 µM for hCA I, 2.04 ± 0.11 µM for hCA II, 3.47 ± 0.88 µM for α-glycosidase, 0.47 ± 0.10 µM for BChE, and 0.58 ± 0.13 µM for AChE, respectively.