New benzimidazole-oxadiazole derivatives as potent VEGFR-2 inhibitors: Synthesis, anticancer evaluation, and docking study.

We report herein, the design and synthesis of benzimidazole-oxadiazole derivatives as new inhibitors for vascular endothelial growth factor receptor-2 (VEGFR-2). The designed members were assessed for their in vitro anticancer activity against three cancer cell lines and two normal cell lines; A549, MCF-7, PANC-1, hTERT-HPNE and CCD-19Lu. Compounds 4c and 4d were found to be the most effective compounds against three cancer cell lines. Compounds 4c and 4d were then tested for their in vitro VEGFR-2 inhibitory activity, safety profiles, and selectivity indices using the normal hTERT-HPNE and CCD-19Lu cell lines. It was determined that compound 4c was the most effective and safe member of the produced chemical family. Vascular endothelial growth factor A (VEGFA) immunolocalizations of compounds 4c and 4d were evaluated relative to control by VEGFA immunofluorescence staining. Compounds 4c and 4d inhibited VEGFR-2 enzyme with half-maximal inhibitory concentration values of 0.475 ± 0.021 and 0.618 ± 0.028 µM, respectively. Molecular docking of the target compounds was carried out in the active site of VEGFR-2 (Protein Data Bank: 4ASD).

Synthesis, DFT Calculations, In Silico Studies, and Antimicrobial Evaluation of Benzimidazole-Thiadiazole Derivatives.

In this study, a series of new benzimidazole-thiadiazole hybrids were synthesized, and the synthesized compounds were screened for their antimicrobial activities against eight species of pathogenic bacteria and three fungal species. Azithromycin, voriconazole, and fluconazole were used as reference drugs in the mtt assay. Among them, compounds 5f and 5h showed potent antifungal activity against C. albicans with a MIC of 3.90 µg/mL. Further, the results of the antimicrobial assay for compounds 5a, 5b, 5f, and 5h proved to be potent against E. faecalis (ATCC 2942) on the basis of an acceptable MIC value of 3.90 µg/mL. The cytotoxic effects of compounds that are effective as a result of their antimicrobial activity on healthy mouse fibroblast cells (L929) were evaluated. According to HOMO-LUMO analysis, compound 5h (with the lower ΔE = 3.417 eV) is chemically more reactive than the other molecules, which is compatible with the highest antibacterial and antifungal activity results. A molecular docking study was performed to understand their binding modes within the sterol 14-α demethylase active site and to interpret their promising fungal inhibitory activities. Molecular dynamics (MD) simulations of the most potent compounds 5f and 5h were found to be quite stable in the active site of the 14-α demethylase (5TZ1) protein.

Design, synthesis, and molecular docking studies of benzimidazole-1,3,4-triazole hybrids as carbonic anhydrase I and II inhibitors.

In this study, with an aim to develop novel heterocyclic hybrids as potent enzyme inhibitors, we synthesized a series of 10 novel 2-(4-(4-ethyl-5-(2-(substitutedphenyl)-2-oxo-ethylthio)-4H-1,2,4-triazol-3-yl)-phenyl)-5,6-dimethyl-1H-benzimidazole (5a-5j) derivatives and characterized by 1 H-NMR, 13 C-NMR, and HRMS. These compounds were evaluated for their inhibitory activity against hCA I and hCA II. All the compounds exhibited good hCA I and hCA II inhibitory activities with IC50 values in range of 1.288 µM-3.122 µM. Among all these compounds, compound 5e, with an IC50 value of 1.288 µM is the most active against carbonic hCA I. Compound 5h with an IC50 value of 1.532 µM is the most active against carbonic hCA-II. Compounds 5a-5j were also evaluated for their cytotoxic effects on the L929 mouse fibroblast (normal) cell line. The compounds were also analyzed for their antioxidant capacity by TAS, FRAP, and DPPH activity. Enzyme inhibition kinetics showed all compounds 5a-5j to inhibit the enzyme by non-competitive. The most active compound 5e for hCA I and compound 5h for hCA-II were subjected to molecular docking, which revealed their binding interactions with the enzyme's active site, confirming the experimental findings.

Synthesis of Benzimidazole-1,2,4-triazole Derivatives as Potential Antifungal Agents Targeting 14α-Demethylase.

Invasive fungal infections (IFIs) are increasing as major infectious diseases around the world, and the limited efficacy of existing medications has resulted in substantial morbidity and death in patients due to the lack of effective antifungal agents and serious drug resistance. In this study, a series of benzimidazole-1,2,4-triazole derivatives (6a-6l) were synthesized and characterized by 1H NMR, 13C NMR, and HR-MS spectral analysis. All the target compounds were screened for their in vitro antifungal activity against four fungal strains, namely, C. albicans, C. glabrata, C. krusei, and C. parapsilopsis. The synthesized compounds exhibited significant antifungal potential, especially against C. glabrata. Three compounds (6b, 6i, and 6j) showed higher antifungal activity with their MIC values (0.97 µg/mL) compared with voriconazole and fluconazole. Molecular docking provided a possible binding mode of compounds 6b, 6i, and 6j in the 14α-demethylase active site. Our studies suggested that the benzimidazole-1,2,4-triazole derivatives can be used as a new fungicidal lead targeting 14α-demethylase for further structural optimization. In addition, their effects on the L929 cell line were also investigated to evaluate the cytotoxic effects of the compounds. SEM analyses were performed to examine the effects of compounds 6a, 6i, and 6j on C. glabrata cells under in vivo experimental conditions.

Synthesis, Biological Evaluation, and Molecular Modeling Studies of New 1,3,4-Thiadiazole Derivatives as Potent Antimicrobial Agents.

In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1 H-NMR, 13 C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 µg/mL of the compounds 3f and 3g, respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds' theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f.

New benzimidazole-oxadiazole derivatives: Synthesis, α-glucosidase, α-amylase activity, and molecular modeling studies as potential antidiabetic agents.

Benzimidazole-1,3,4-oxadiazole derivatives (5a-z) were synthesized and characterized with different spectroscopic techniques such as 1 H NMR, 13 C NMR, and HRMS. The synthesized analogs were examined against α-glucosidase and α-amylase enzymes to determine their antidiabetic potential. Compounds 5g and 5q showed the most activity with 35.04 ± 1.28 and 47.60 ± 2.16 µg/mL when compared with the reference drug acarbose (IC50 = 54.63 ± 1.95 µg/mL). Compounds 5g, 5o, 5s, and 5x were screened against the α-amylase enzyme and were found to show excellent potential, with IC50 values ranging from 22.39 ± 1.40 to 32.07 ± 1.55 µg/mL, when compared with the standard acarbose (IC50 = 46.21 ± 1.49 µg/mL). The antioxidant activities of the effective compounds (5o, 5g, 5s, 5x, and 5q) were evaluated by TAS methods. A molecular docking research study was conducted to identify the active site and explain the functions of the active chemicals. To investigate the most likely binding mode of the substances 5g, 5o, 5q, 5s, and 5x, a molecular dynamics simulation was also carried out.

Design, synthesis, molecular modeling, DFT, ADME and biological evaluation studies of some new 1,3,4-oxadiazole linked benzimidazoles as anticancer agents and aromatase inhibitors.

Breast cancer is the most frequent female cancer and second cause of cancer-related deaths among women around the world. Two thirds of breast cancer patients have hormone-dependent tumors, which is very likely be treated with hormonal therapy. Aromatase is involved in the biosynthesis of estrogen thus a critical target for breast cancer. In this study, in order to identify new aromatase enzyme inhibitors, a series of benzimidazole-1,3,4-oxadiazole derivatives were synthesized and characterized by 1H NMR, 13C NMR, and MS spectra analyses. In the in vitro anticancer assay, all the compounds tested anticancer activities using MTT-based assay against five cancer cell lines (MCF-7, A549, HeLa, C6, and HepG2). Among them, compound 5a exhibited the most potent activity with IC50 values of 5.165 ± 0.211 µM and 5.995 ± 0.264 µM against MCF-7 and HepG2 cell lines. Compound 5a was included in the BrdU test to determine the DNA synthesis inhibition effects for both cell types. Furthermore, compound 5c was also found to be more effective than doxorubicin on the HeLa cell line. The selectivity of anticancer activity was evaluated in NIH3T3 cell line. In vitro, enzymatic inhibition assays of aromatase enzyme were performed for compound 5a acting on the MCF-7 cell line. For compound 5a, in silico molecular docking and dynamics simulations against aromatase enzyme was performed to determine possible protein-ligand interactions and stability. DFT study was performed to evaluate the quantum mechanical and electronic properties of compound 5a. Finally, the theoretical ADME properties of the potential aromatase inhibitor compound 5a were analyzed by calculations.Communicated by Ramaswamy H. Sarma.

Design, synthesis, biological evaluation, and docking studies of some novel chalcones as selective COX-2 inhibitors.

A new series of chalcones (1-9) possessing an SO2 CH3 COX-2 pharmacophore at the para position of the C-1 phenyl ring was synthesized via the Claisen-Schmidt condensation reaction and examined for their inhibition potential against cyclooxygenase (COX) enzymes. Their structures were elucidated by infrared, 1 H NMR (nuclear magnetic resonance), 13 C NMR, and high-resolution mass spectroscopic methods. Enzyme inhibition studies revealed that most of the compounds showed a moderate-to-strong inhibitory activity (IC50 = 0.18-0.34 µM) against the COX-2 enzyme as compared with celecoxib (IC50 = 0.12 µM), ibuprofen (IC50 = 5.33 µM), and nimesulide (IC50 = 1.68 µM). Among these compounds, 1-[4-(methylsulfonyl)phenyl]-3-(2,3-dichlorophenyl)prop-2-en-1-one (5), 1-[4-(methylsulfonyl)phenyl]-3-(2,4-dichlorophenyl)prop-2-en-1-one (6), and 1-[4-(methylsulfonyl)phenyl]-3-(2-chloro-6-fluorophenyl)prop-2-en-1-one (8) became prominent with IC50 values of 0.21, 0.19, and 0.18 µM, respectively. According to molecular docking studies of the most effective compounds, it was found that the compounds interact with amino acids that are important in COX-2 selectivity, such as Arg499 and Phe504.

Synthesis of some new benzoxazole derivatives and investigation of their anticancer activities.

Phortress is an anticancer prodrug, which has active metabolite (5F-203) being potent agonist of the aryl hydrocarbon receptor (AhR). The 5F-203 switches on cytochrome P450 CYP1A1 gene expression and thus exhibits anticancer activity. In this study, it is aimed to obtain new phortress analogues by bioisosteric replacement of benzothiazole core in the structure to benzoxazole ring system. Synthesis of compounds (3a-3p) were performed according to literature methods. Their structures were elucidated by IR, 1H NMR, 13C NMR, 2D-NMR and HRMS spectroscopic methods. Cytotoxicity (MTT), inhibition of DNA synthesis and flow cytometric analysis assays were applied to determine anticancer activity of the compounds on colon (HT-29), breast (MCF7), lung (A549), liver (HepG2) and brain (C6) carcinoma cell types. When compared reference agent doxorubicin, compounds 3m and 3n displayed very attractive anticancer effect against carcinogenic cell lines. Due to structural similarity to phortress, biotransformation studies for 3m and 3n were examined by LCMS-IT-TOF system and probable metabolites of these compounds were determined. Induction potential of these compounds on CYP1A1/2 enzymes was also investigated to clarify possible mechanism of action. Interaction modes between CYP1A1 enzyme and compound 3n or its some metabolites were investigated by docking studies. In conclusion, findings of these study indicate that compounds 3m and 3n possess significant anticancer activity, probably with the same mechanism of action to Phortress.

Design, Synthesis, In Vitro and In Silico Studies of New Thiazolylhydrazine-Piperazine Derivatives as Selective MAO-A Inhibitors.

Monoamine oxidase (MAO) isoenzymes are very important drug targets among neurological disorders. Herein, novel series of thiazolylhydrazine-piperazine derivatives were designed, synthesized and evaluated for their MAO-A and -B inhibitory activity. The structures of the synthesized compounds were assigned using different spectroscopic techniques such as 1H-NMR, 13C-NMR and HRMS. Moreover, the prediction of ADME (Absorption, Distribution, Metabolism, Elimination) parameters for all of the compounds were performed using in silico method. According to the enzyme inhibition results, the synthesized compounds showed the selectivity against MAO-A enzyme inhibition. Compounds 3c, 3d and 3e displayed significant MAO-A inhibition potencies. Among them, compound 3e was found to be the most effective derivative with an IC50 value of 0.057 ± 0.002 µM. Moreover, it was seen that this compound has a more potent inhibition profile than the reference inhibitors moclobemide (IC50 = 6.061 ± 0.262 µM) and clorgiline (IC50 = 0.062 ± 0.002 µM). In addition, the enzyme kinetics were performed for compound 3e and it was determined that this compound had a competitive and reversible inhibition type. Molecular modeling studies aided in the understanding of the interaction modes between this compound and MAO-A. It was found that compound 3e had significant and important binding property.

Design, Synthesis, and Structure-Activity Relationships of Thiazole Analogs as Anticholinesterase Agents for Alzheimer's Disease.

Dementia is a neurological condition commonly correlated with Alzheimer's disease (AD), and it is seen with many other central nervous system (CNS) disorders. The restricted number of medications is not appropriate to offer enough relief to enhance the quality of life of patients suffering from this symptom; thus, all therapeutic choices should be carefully assessed. In this study, new thiazolylhydrazone derivatives (2a-2l) were designed and synthesized based on the cholinergic hypothesis. Their chemical structures were confirmed by 1H NMR, 13C NMR, and HRMS spectrometric techniques. The ADME (absorption, distribution, metabolism, elimination) parameters of the synthesized compounds were predicted by using QikProp 4.8 software. It was concluded that all compounds presented satisfactory drug-like characteristics. Furthermore, their inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in vitro were also tested by modified the Ellman spectrophotometric method. According to the results, all compounds showed a weak inhibitory effect on BChE. On the other hand, most of the compounds (2a, 2b, 2d, 2e, 2g, 2i, and 2j) had a certain AChE inhibitory activity, and the IC50 values of them were calculated as 0.063 ± 0.003, 0.056 ± 0.002, 0.147 ± 0.006, 0.040 ± 0.001, 0.031 ± 0.001, 0.028 ± 0.001, and 0.138 ± 0.005 µM, respectively. Among these derivatives, compound 2i was found to be the most active agent in the series with an IC50 value of 0.028 ± 0.001 µM, which indicated an inhibition profile at a similar rate as the reference drug, donepezil. The potential binding modes of compounds 2a, 2b, 2e, 2g, and 2i with AChE were investigated and compared with each other by the molecular docking studies. The results showed that these compounds were strongly bound up with the AChE enzyme active site with the optimal conformations.

Synthesis, anticancer evaluation and molecular docking studies of new benzimidazole- 1,3,4-oxadiazole derivatives as human topoisomerase types I poison.

In this study, some benzimidazole-oxadiazole derivatives were synthesised and tested for their in vitro anticancer activities on five cancer cell lines, including HeLa, MCF7, A549, HepG2 and C6. Their structures were elucidated by IR, 1H-NMR, 13C-NMR, 2 D-NMR and HRMS spectroscopic methods. Among all screened compounds; 5a, 5b, 5d, 5e, 5k, 5l, 5n and 5o exhibited potent selective cytotoxic activities against various tested cancer cell lines. Especially, compounds 5l and 5n exhibited the most antiproliferative activity than Hoechst 33342 and doxorubicin against HeLa cell line, with IC50 of 0.224 ± 0.011 µM and 0.205 ± 0.010 µM, respectively. Furthermore, these potent lead cytotoxic agents were evaluated in terms of their inhibition potency against Topoisomerase I and it was determined that selected compounds inhibited the Topoisomerase I. Docking studies were performed and probable interactions in the DNA-Topo I enzyme complex was determined.

Synthesis, in vitro enzyme activity and molecular docking studies of new benzylamine-sulfonamide derivatives as selective MAO-B inhibitors.

Many studies have been conducted on the selective inhibition of human monoamine oxidase B (hMAO-B) enzyme using benzylamine-sulphonamide derivatives. Using various chemical modifications on BB-4h, which was reported previously by our team and showed a significant level of MAO-B inhibition, novel benzylamine-sulphonamide derivatives were designed, synthesised, and their MAO inhibition potentials were evaluated. Among the tested derivatives, compounds 4i and 4t achieved IC50 values of 0.041 ± 0.001 µM and 0.065 ± 0.002 µM, respectively. The mechanism of hMAO-B inhibition by compounds 4i and 4t was studied using Lineweaver-Burk plot. The nature of inhibition was also determined to be non-competitive. Cytotoxicity tests were conducted and compounds 4i and 4t were found to be non-toxic. Molecular docking studies were also carried out for compound 4i, which was found as the most potent agent, within hMAO-B catalytic site.

Synthesis, Docking Studies and Biological Activity of New Benzimidazole- Triazolothiadiazine Derivatives as Aromatase Inhibitor.

In the last step of estrogen biosynthesis, aromatase enzyme catalyzes the conversion of androgens to estrogens. Aromatase inhibition is an important way to control estrogen-related diseases and estrogen levels. In this study, sixteen of benzimidazole-triazolothiadiazine derivatives have been synthesized and studied as potent aromatase inhibitors. First, these compounds were tested for their anti-cancer properties against human breast cancer cell line (MCF-7). The most active compounds 5c, 5e, 5k, and 5m on MCF-7 cell line were subject to further in vitro aromatase enzyme inhibition assays to determine the possible mechanisms of action underlying their activity. Compound 5e showed slight less potent aromatase inhibitory activity than that of letrozole with IC50 = 0.032 ± 0.042 µM, compared to IC50 = 0.024 ± 0.001 µM for letrozole. Furthermore, compound 5e and reference drug letrozole were docked into human placental aromatase enzyme to predict their possible binding modes with the enzyme. Finally, ADME parameters (absorption, distribution, metabolism, and excretion) of synthesized compounds (5a-5p) were calculated by QikProp 4.8 software.

Synthesis and docking study of benzimidazole-triazolothiadiazine hybrids as aromatase inhibitors.

Aromatase is involved in the biosynthesis of estrogen and thus is a critical target for breast cancer. In this study, to identify new aromatase enzyme inhibitors, seven 3-[4-(5-methyl-1H-benzo[d]imidazol-2-yl)phenyl]-6-(substituted phenyl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine derivatives were synthesized. First, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to determine the inhibitory activity of the synthesized compounds on the MCF-7 cell line. The aromatase inhibitory activity was determined for the active compounds 5b, 5c, 5e, and 5g on the MCF-7 cell line. Compound 5g showed significant aromatase inhibitory activity (IC50 = 0.037 ± 0.001 µM). Interestingly, this compound, which bears a difluoro substituent at positions 2 and 4 of the phenyl ring, displayed the most potent aromatase inhibitory activity without significant cytotoxicity to a normal healthy cell line (NIH3T3). Furthermore, the interactions between the best active compounds and the active site of the enzyme were analyzed through a docking study. The results of this study determined that benzimidazole-triazolothiadiazine derivatives are promising compounds that should be further developed as a novel class of aromatase inhibitors.

Novel 1,3,4-thiadiazole compounds as potential MAO-A inhibitors - design, synthesis, biological evaluation and molecular modelling.

Monoamine oxidases (MAOs) are important drug targets for the management of neurological disorders. Herein, a series of new 1,3,4-thiadiazole derivatives bearing various alkyl/arylamine moieties as MAO inhibitors were designed and synthesized. All of the compounds were more selective against hMAO-A than hMAO-B. The half maximal inhibitory concentration (IC50) values of most of the compounds were lower than that of the common drug moclobemide (IC50 = 4.664 µM) and compound 6b was proven to be the most active compound (IC50 = 0.060 µM). Moreover, it was seen that compound 6b showed a similar inhibition profile to that of clorgyline (IC50 = 0.048 µM). The inhibition profile was found to be reversible and competitive for compound 6b with MAO-A selectivity. Molecular modelling studies aided in the understanding of the interaction modes between compound 6b and MAO-A. Furthermore, this compound was predicted to have a good pharmacokinetic profile and high BBB penetration. Therefore, such compounds are of interest towards developing new MAO inhibitors.

Synthesis and AChE Inhibitory Activity of Novel Thiazolylhydrazone Derivatives.

Alzheimer's disease (AD) is the most common of the degenerative brain diseases and is described together with the impairment of cognitive function. Patients with AD lose the capability to code new memories, and life conditions are extremely difficult. The development of new drugs in this area continues at a great pace. A novel series of thiazole-piperazine hybrids, aimed against Alzheimer's disease (AD), have been synthesized. The structure identification of synthesized compounds was elucidated by 1HNMR, 13C-NMR, and LCMSMS spectroscopic methods. The inhibitory potential of the synthesized compounds on cholinesterase enzymes was investigated. The compounds 3a, 3c and 3i showed significant inhibitory activity on the acetylcholinesterase (AChE) enzyme. On the other hand, none of the compounds showed significant inhibitory activity on the butyrylcholinesterase (BChE) enzyme. In addition to enzyme inhibition studies, enzyme kinetic studies were performed to observe the effects of the most active inhibitor compounds on the substrate-enzyme relationship. In addition to in vitro tests, docking studies also indicated that compound 3c potentially acts as a dual binding site AChE inhibitor.

Synthesis and AChE-Inhibitory Activity of New Benzimidazole Derivatives.

Alzheimer's disease (AD), one of the main causes of aged dementia, is a progressive and degenerative neurological disorder characterized by loss of cognition and memory. Although the symptomatic treatment of AD, particularly acetylcholinesterase inhibitors (AChEIs) based on the 'cholinergic hypothesis', has been successful in clinic, at present there is no cure for this disease. In this study, we designed compounds carrying benzimidazole and triazole rings on the same chemical skeleton so as to investigate their potential acetylcholinesterase and butyrylcholinesterase activity. Furthermore, molecular modeling study was performed to determine the binding mode of the best inhibitor to the AChE. Among them, compounds 3d and 3h, which featured 3,4-dihydroxy substitution at the phenyl ring and 5(6)-chloro substitution at the benzimidazole ring were found to be potent inhibitors of AChE. The inhibition kinetics of the two most active derivatives 3d and 3h were further studied. The kinetic displayed increasing slope and increasing intercept, which is consistent with a mixed inhibition. The IC50 and Ki values of 3d are 31.9 ± 0.1 nM and 26.2 nM, respectively. Compound 3h exhibited IC50 of 29.5 ± 1.2 nM and Ki of 24.8 nM. The above data compared favorably with data for donepezil (21.8 ± 0.9 nM) the reference compound in our study.

Synthesis and Antifungal Potential of Some Novel Benzimidazole-1,3,4-Oxadiazole Compounds.

Discovery of novel anticandidal agents with clarified mechanisms of action, could be a rationalist approach against diverse pathogenic fungal strains due to the rise of resistance to existing drugs. In support to this hypothesis, in this paper, a series of benzimidazole-oxadiazole compounds were synthesized and subjected to antifungal activity evaluation. In vitro activity assays indicated that some of the compounds exhibited moderate to potent antifungal activities against tested Candida species when compared positive control amphotericin B and ketoconazole. The most active compounds 4h and 4p were evaluated in terms of inhibitory activity upon ergosterol biosynthesis by an LC-MS-MS method and it was determined that they inhibited ergosterol synthesis concentration dependently. Docking studies examining interactions between most active compounds and lanosterol 14-α-demethylase also supported the in vitro results.

In vitro and in silico evaluation of new thiazole compounds as monoamine oxidase inhibitors.

New twenty compounds bearing thiazole ring (3a-3t) were designed and synthesized as monoamine oxidase (MAO) inhibitors. The fluorometric enzyme inhibition assay was used to determine the biological effects of synthesized compounds. Most of them showed remarkable inhibitory activity against both MAO-A and MAO-B. By comparing their IC50 values, it can be seen that active derivatives displayed generally selectivity on MAO-B enzyme. Compounds 3j and 3t, which bear dihydroxy moiety at the 3rd and 4th position of phenyl ring, were the most active derivatives in the series against both isoenzymes. Compounds 3j and 3t showed significant inhibition profile on MAO-A with the IC50 values of 0.134 ±â€¯0.004 µM and 0.123 ±â€¯0.005 µM, respectively, while they performed selectivity against MAO-B with the IC50 values of 0.027 ±â€¯0.001 µM and 0.025 ±â€¯0.001 µM, respectively. Also, docking studies about these compounds were carried out to evaluate their binding modes on the active regions of MAO-A and MAO-B.