A rational design strategy of the novel topoisomerase II inhibitors for the synthesis of the 4-O-(2-pyrazinecarboxylic)-4′-demethylepipodophyllotoxin with antitumor activity by diminishing the relaxation reaction of topoisomerase II-DNA decatenation

A rational design strategy of the novel podophyllum topoisomerase II (Topo II) inhibitors for the synthesis of the esterification and amidation substituted 4′-demethylepipodophyllotoxin (DMEP) derivates was developed in order to discover the potential antitumor prodrug. Firstly, according to the structure–activity relationship, drug combination principle and bioisosterism, the –COO– and the –NH– bond substituents at the 4 position of cycloparaffin would be a great modification direction to improve antitumor activity of 4′-demethylepipodophyllotoxin (DMEP). Secondly, from the prodrug principle view, the esterification and amidation at the C-4 position of DMEP would be two useful structure modifications for improve solubility. Thirdly, from the activity pocket in Topo II-DNA cleavage complex point of view, a series of heterocyclic with pharmacological activity were chosen as module for improving antitumor activity by binding with Topo II. Finally, nine novel esterification and amidation DMEP derivates were designed and synthesized for the potential Topo II inhibitors with the superior biological activity. All the novel compounds exhibited promising in vitro antitumor activity, especially 4-O-(2-pyrazinecarboxylic)-4′-demethylepipodophyllotoxin (compound 1). The antitumor activity of compound 1 against tumor cell line HeLa (i.e., the IC₅₀ value of 0.60 ± 0.20 μM), A549 (i.e., the IC₅₀ value of 3.83 ± 0.08 μM), HepG2 (i.e., the IC₅₀ value of 1.21 ± 0.05 μM), and BGC-823 (i.e., the IC₅₀ value of 4.15 ± 1.13 μM) was significantly improved by 66, 16, 12, and 6 times than that of the clinically important podophyllum anticancer drug etoposide (i.e., the IC₅₀ values of 15.32 ± 0.10, 59.38 ± 0.77, 67.25 ± 7.05, and 30.74 ± 5.13 μM), respectively. Compound 1 could arrest HeLa cell cycle G₂/M and induce apoptosis by strongly diminishing the relaxation reaction of Topo II-DNA decatenation. The correctness of rational drug design was strictly demonstrated by the bioactivity test.     

LuxR-dependent quorum sensing: Computer aided discovery of new inhibitors structurally unrelated to N-acylhomoserine lactones

A virtual screening, involving flexible docking sequences within the LuxR, TraR and LasR binding sites, was used as a structural binding sites similarity filter to specifically target conserved residues in the proteins of the LuxR family (namely Tyr62, Trp66, Tyr70, Asp79, Trp94 for LuxR). This docking-based screening, employing a genetic algorithm, was performed on a 2344 chemical compounds library, together with empirical binding free energy (ΔG_bind) calculations. Docking results were analysed, and the compounds detected with reproducible low ΔG_bind values or identified as being in the top 120 for most of the docking sequences, were selected as hits candidates which interact with conserved residues. Biological evaluation with LuxR-dependent quorum sensing led to the discovery of some new inhibitors, namely tamoxifen, sertraline, pimethixene, terfenadine, fendiline and calmidazolium. Notably, calmidazolium was identified as one of the most potent AHL-structurally unrelated inhibitors of LuxR-dependent quorum sensing, with an IC₅₀ value of 7.0 ± 0.2 μM.     

Structure activity relationship modelling of milk protein-derived peptides with dipeptidyl peptidase IV (DPP-IV) inhibitory activity

Quantitative structure activity type models were developed in an attempt to predict the key features of peptide sequences having dipeptidyl peptidase IV (DPP-IV) inhibitory activity. The models were then employed to help predict the potential of peptides, which are currently reported in the literature to be present in the intestinal tract of humans following milk/dairy product ingestion, to act as inhibitors of DPP-IV. Two models (z- and v-scale) for short (2–5 amino acid residues) bovine milk peptides, behaving as competitive inhibitors of DPP-IV, were developed. The z- and the v-scale models (p < 0.05, R² of 0.829 and 0.815, respectively) were then applied to 56 milk protein-derived peptides previously reported in the literature to be found in the intestinal tract of humans which possessed a structural feature of DPP-IV inhibitory peptides (P at the N₂ position). Ten of these peptides were synthetized and tested for their in vitro DPP-IV inhibitory properties. There was no agreement between the predicted and experimentally determined DPP-IV half maximal inhibitory concentrations (IC₅₀) for the competitive peptide inhibitors. However, the ranking for DPP-IV inhibitory potency of the competitive peptide inhibitors was conserved. Furthermore, potent in vitro DPP-IV inhibitory activity was observed with two peptides, LPVPQ (IC₅₀ = 43.8 ± 8.8 μM) and IPM (IC₅₀ = 69.5 ± 8.7 μM). Peptides present within the gastrointestinal tract of human may have promise for the development of natural DPP-IV inhibitors for the management of serum glucose.     

Synthesis of triazole Schiff bases: Novel inhibitors of nucleotide pyrophosphatase/phosphodiesterase-1

A series of Schiff base triazoles 1–25 was synthesized and evaluated for their nucleotide pyrophosphatase/phosphodiesterase-1 inhibitory activities. Among twenty-five compounds, three compounds 10 (IC₅₀ = 132.20 ± 2.89 μM), 13 (IC₅₀ = 152.83 ± 2.39 μM), and 22 (IC₅₀ = 251.0 ± 6.64 μM) were identified as potent inhibitors with superior activities than the standard EDTA (IC₅₀ = 277.69 ± 2.52 μM). The newly identified inhibitors may open a new avenue for the development of treatment of phosphodiesterase-I related disorders. These compounds were also evaluated for carbonic anhydrase, acetylcholinesterase and butyrylcholinesterase inhibitory potential and were found to be inactive. The compounds showed non-toxic effect towards PC3 cell lines.     

Identification of new potent inhibitor of aldose reductase from Ocimum basilicum

Recent efforts to develop cure for chronic diabetic complications have led to the discovery of potent inhibitors against aldose reductase (AKR1B1, EC 1.1.1.21) whose role in diabetes is well-evident. In the present work, two new natural products were isolated from the ariel part of Ocimum basilicum; 7-(3-hydroxypropyl)-3-methyl-8-β-O-d-glucoside-2H-chromen-2-one (1) and E-4-(6′-hydroxyhex-3′-en-1-yl)phenyl propionate (2) and confirmed their structures with different spectroscopic techniques including NMR spectroscopy etc. The isolated compounds (1, 2) were evaluated for in vitro inhibitory activity against aldose reductase (AKR1B1) and aldehyde reductase (AKR1A1). The natural product (1) showed better inhibitory activity for AKR1B1 with IC₅₀ value of 2.095 ± 0.77 µM compare to standard sorbinil (IC₅₀ = 3.14 ± 0.02 µM). Moreover, the compound (1) also showed multifolds higher activity (IC₅₀ = 0.783 ± 0.07 µM) against AKR1A1 as compared to standard valproic acid (IC₅₀ = 57.4 ± 0.89 µM). However, the natural product (2) showed slightly lower activity for AKR1B1 (IC₅₀ = 4.324 ± 1.25 µM). Moreover, the molecular docking studies of the potent inhibitors were also performed to identify the putative binding modes within the active site of aldose/aldehyde reductases.     

In silico binding analysis and SAR elucidations of newly designed benzopyrazine analogs as potent inhibitors of thymidine phosphorylase

Thymidine phosphorylase (TP) is up regulated in wide variety of solid tumors and therefore presents a remarkable target for drug discovery in cancer. A novel class of extremely potent TPase inhibitors based on benzopyrazine (1–28) has been developed and evaluated against thymidine phosphorylase enzyme. Out of these twenty-eight analogs eleven (11) compounds 1, 4, 14, 15, 16, 17, 18, 19, 20, 24 and 28 showed potent thymidine phosphorylase inhibitory potentials with IC₅₀ values ranged between 3.20 ± 0.30 and 37.60 ± 1.15 μM when compared with the standard 7-Deazaxanthine (IC₅₀ = 38.68 ± 4.42 μM). Structure-activity relationship was established and molecular docking studies were performed to determine the binding interactions of these newly synthesized compounds. Current studies have revealed that these compounds established stronger hydrogen bonding networks with active site residues as compare to the standard compound 7DX.     

Carbonic anhydrase inhibitory properties of novel benzylsulfamides using molecular modeling and experimental studies

In this study, a series of sulfamoyl carbamates and sulfamide derivatives were synthesized. Six commercially available benzyl amines and BnOH were reacted with chlorosulfonyl isocyanate (CSI) to give sulfamoyl carbamates. Pd–C catalyzed hydrogenolysis reactions of carbamates afforded sulfamides. The inhibition effects of novel benzylsulfamides on the carbonic anhydrase I, and II isoenzymes (CA I, and CA II) purified from fresh human blood red cells were determined by Sepharose-4B-L-Tyrosine-sulfanilamide affinity chromatography. In vitro studies were shown that all of novel synthesized benzylsulfamide analogs inhibited, concentration dependently, both hCA isoenzyme activities. The novel benzylsulfamide compounds investigated here exhibited nanomolar inhibition constants against the two isoenzymes. K_i values were in the range of 28.48 ± 0.01–837.09 ± 0.19 nM and 112.01 ± 0.01–268.01 ± 0.22 nM for hCAI and hCA II isoenzymes, respectively. Molecular modeling approaches were also applied for studied compounds.     

The effects of mitochondrial complex I blockade on ATP and permeability in rat pulmonary microvascular endothelial cells in culture (PMVEC) are overcome by coenzyme Q1 (CoQ1)

In isolated rat lung perfused with a physiological saline solution (5.5 mM glucose), complex I inhibitors decrease lung tissue ATP and increase endothelial permeability (K_f), effects that are overcome using an amphipathic quinone (CoQ₁) [Free Radic. Biol. Med. 65:1455–1463; 2013]. To address the microvascular endothelial contribution to these intact lung responses, rat pulmonary microvascular endothelial cells in culture (PMVEC) were treated with the complex I inhibitor rotenone and ATP levels and cell monolayer permeability (PS) were measured. There were no detectable effects on ATP or permeability in experimental medium that, like the lung perfusate, contained 5.5 mM glucose. To unmask a potential mitochondrial contribution, the glucose concentration was lowered to 0.2 mM. Under these conditions, rotenone decreased ATP from 18.4±1.6 (mean±SEM) to 4.6±0.8 nmol/mg protein, depolarized the mitochondrial membrane potential (Δψ_m) from −129.0±3.7 (mean±SEM) to −92.8±5.5 mV, and decreased O₂ consumption from 2.0±0.1 (mean±SEM) to 0.3±0.1 nmol/min/mg protein. Rotenone also increased PMVEC monolayer permeability (reported as PS in nl/min) to FITC–dextran (~40 kDa) continually over a 6 h time course. When CoQ₁ was present with rotenone, normal ATP (17.4±1.4 nmol/mg protein), O₂ consumption (1.5±0.1 nmol/min/mg protein), Δψ_m (−125.2±3.3 mV), and permeability (PS) were maintained. Protective effects of CoQ₁ on rotenone-induced changes in ATP, O₂ consumption rate, Δψ_m, and permeability were blocked by dicumarol or antimycin A, inhibitors of the quinone-mediated cytosol–mitochondria electron shuttle [Free Radic. Biol. Med. 65:1455–1463; 2013]. Key rotenone effects without and with CoQ₁ were qualitatively reproduced using the alternative complex I inhibitor, piericidin A. We conclude that, as in the intact lung, PMVEC ATP supply is linked to the permeability response to complex I inhibitors. In contrast to the intact lung, the association in PMVEC was revealed only after decreasing the glucose concentration in the experimental medium from 5.5 to 0.2 mM.     

Synthesis,in vitro evaluation and molecular docking studies of thiazole derivatives as new inhibitors of α-glucosidase

A series of thiazole derivatives 1–21 were prepared, characterized by EI-MS and ¹H NMR and evaluated for α-glucosidase inhibitory potential. All twenty one derivatives showed good α-glucosidase inhibitory activity with IC₅₀ value ranging between 18.23 ± 0.03 and 424.41 ± 0.94 μM when compared with the standard acarbose (IC₅₀, 38.25 ± 0.12 μM). Compound (8) (IC₅₀, 18.23 ± 0.03 μM) and compound (7) (IC₅₀ = 36.75 ± 0.05 μM) exhibited outstanding inhibitory potential much better than the standard acarbose (IC₅₀, 38.25 ± 0.12 μM). All other analogs also showed good to moderate enzyme inhibition. Molecular docking studies were carried out in order to find the binding affinity of thiazole derivatives with enzyme. Studies showed these thiazole analogs as a new class of α-glucosidase inhibitors.     

2,2′-Dihydroxybenzophenones and their carbonyl N-analogues as inhibitor scaffolds for MDR-involved human glutathione transferase isoenzyme A1-1

The MDR-involved human GSTA1-1, an important isoenzyme overexpressed in several tumors leading to chemotherapeutic-resistant tumour cells, has been targeted by 2,2′-dihydroxybenzophenones and some of their carbonyl N-analogues, as its potential inhibitors. A structure-based library of the latter was built-up by a nucleophilic cleavage of suitably substituted xanthones to 2,2′-dihydroxy-benzophenones (5–9) and subsequent formation of their N-derivatives (oximes 11–13 and N-acyl hydrazones 14–16). Screening against hGSTA1-1 led to benzophenones 6 and 8, and hydrazones 14 and 16, having the highest inhibition potency (IC₅₀ values in the range 0.18 ± 0.02 to 1.77 ± 0.10 μM). Enzyme inhibition kinetics, molecular modeling and docking studies showed that they interact primarily at the CDNB-binding catalytic site of the enzyme. In addition, the results from cytotoxicity studies with human colon adenocarcinoma cells showed low LC₅₀ values for benzophenone 6 and its N-acyl hydrazone analogue 14 (31.4 ± 0.4 μM and 87 ± 1.9 μM, respectively), in addition to the strong enzyme inhibition profile (IC₅₀₍₆₎ = 1,77 ± 0.10 μM; IC₅₀₍₁₄₎ = 0.33 ± 0.05 μM). These structures may serve as leads for the design of new potent mono- and bi-functional inhibitors and pro-drugs against human GTSs.     

Rational design and synthesis of dihydropyrimidine based dual binding site acetylcholinesterase inhibitors

Based on the pharmacological importance of dihydropyrimidine (DHPM) scaffold, substituted DHPMs linked with acetamide linker to substituted aromatic anilines were synthesized and evaluated for their potency as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. The good AChE inhibitory activity of 4-dihydropyrimidine-2-thione (4a–h) and 2-amino-1,4-dihyropyrimidines (5a–h) series was observed with compound 4a and 4d identified as the most potent compounds with IC₅₀ values of 0.17 ± 0.01 and 0.39 ± 0.04 μM respectively. The inhibition of BChE was found in a broader range of concentrations (2.37–56.32 μM). To explore the binding insights into the enzyme, molecular docking study was carried out using GOLD software. The binding mode analysis indicated that all of these inhibitors are well accommodated in the active site and interact with the key amino acid residues of Catalytic anionic site (CAS) and peripheral anionic site (PAS). Furthermore, in silico ADMET predictions suggest that these compounds are non-AMES toxic with good blood brain barrier (BBB) penetration, human intestinal absorption.     

Design,synthesis, biological evaluation of substituted benzofurans as DNA gyraseB inhibitors of Mycobacterium tuberculosis

DNA gyrase of Mycobacterium tuberculosis (MTB) is a type II topoisomerase and is a well-established and validated target for the development of novel therapeutics. By adapting the medium throughput screening approach, we present the discovery and optimization of ethyl 5-(piperazin-1-yl) benzofuran-2-carboxylate series of mycobacterial DNA gyraseB inhibitors, selected from Birla Institute of Technology and Science (BITS) database chemical library of about 3000 molecules. These compounds were tested for their biological activity; the compound 22 emerged as the most active potent lead with an IC₅₀ of 3.2 ± 0.15 μM against Mycobacterium smegmatis DNA gyraseB enzyme and 0.81 ± 0.24 μM in MTB supercoiling activity. Subsequently, the binding of the most active compound to the DNA gyraseB enzyme and its thermal stability was further characterized using differential scanning fluorimetry method.     

Design,synthesis and preliminary activity assay of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid derivatives as novel Histone deacetylases (HDACs) inhibitors

Histone deacetylases (HDACs) are enzymes involved in tumor genesis and development. Herein, we report a novel series of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid derivatives as HDACs inhibitors. The preliminary biological screening showed that most of our compounds exhibited potent inhibitory activity against HDACs. Within this series, five compounds, 13a (IC₅₀ = 0.58 ± 0.10 μM), 7d (IC₅₀ = 1.00 ± 0.16 μM), 8l (IC₅₀ = 1.06 ± 0.14 μM), 7i (IC₅₀ = 1.17 ± 0.19 μM) and 7a (IC₅₀ = 1.29 ± 0.15 μM) possessed better HDACs inhibitory activity than Vorinostat (IC₅₀ = 1.48 ± 0.20 μM). So these five compounds could be used as novel lead compounds for further design of HDACs inhibitors. The anti-proliferative activities of a few compounds and the structure–activity relationships are also briefly discussed.     

Design,synthesis and biological evaluation of novel tripeptidyl epoxyketone derivatives constructed from β-amino acid as proteasome inhibitors

A series of novel tripeptidyl epoxyketone derivatives constructed from β-amino acid were designed, synthesized and evaluated as proteasome inhibitors. All target compounds were tested for their proteasome inhibitory activities and selected compounds were tested for their anti-proliferation activities against two multiple myeloma (MM) cell lines RPMI 8226 and NCI-H929. Among them, eleven compounds exhibited proteasome inhibitory rates of more than 50% at the concentration of 1 μg/mL and nine compounds showed anti-proliferation activities with IC₅₀ values at low micromolar level. Compound 20h displayed the most potent proteasome inhibitory activities (IC₅₀: 0.11 ± 0.01 μM) and anti-proliferation activities with IC₅₀ values at 0.23 ± 0.01 and 0.17 ± 0.02 μM against two tested cell lines. Additionally, the poly-ubiquitin accumulation in the western blot analysis supported that proteasome inhibition in a cellular system was induced by compound 20h. All these experimental results confirmed that β-amino acid can be introduced as a building block for the development of proteasome inhibitors.     

Angiotensin II-induced activation of c-Ret signaling is critical in ureteric bud branching morphogenesis

The renin-angiotensin system (RAS) plays a critical role in ureteric bud (UB) and kidney morphogenesis. Mutations in the genes encoding components of the RAS cause a spectrum of congenital abnormalities of the kidney and urinary tract (CAKUT). However, the mechanisms by which aberrations in the RAS result in CAKUT are poorly understood. Given that c-Ret receptor tyrosine kinase (RTK) is a major inducer of UB branching, the present study tested the hypothesis that angiotensin (Ang) II-induced activation of c-Ret plays a critical role in UB branching morphogenesis. E12.5 mice metanephroi were grown for 24 h in the presence or absence of Ang II, Ang II AT₁ receptor (AT₁R) antagonist candesartan, phosphatidylinositol 3-kinase (PI3 K) inhibitor LY294002 or ERK1/2 inhibitor PD98059. Ang II increased the number of UB tips (61 ± 2.4 vs. 45 ± 4.3, p < 0.05) compared with control. Quantitative RT-PCR analysis demonstrated that Ang II increased c-Ret mRNA levels in the kidney (1.35 ± 0.05 vs. 1.0 ± 0, p < 0.01) and in the UB cells (1.28 ± 0.04 vs. 1.0 ± 0, p < 0.01) compared to control. This was accompanied by increased Tyr¹⁰⁶²Ret phosphorylation by Ang II (5.5 ± 0.9 vs. 1.8 ± 0.4 relative units, p < 0.05). In addition, treatment of UB cells with Ang II (10^?5 M) increased phosphorylation of Akt compared to control (213 ± 16 vs. 100 ± 20%, p < 0.05). In contrast, treatment of metanephroi or UB cells with candesartan decreased c-Ret mRNA levels (0.72 ± 0.06 vs. 1.0 ± 0, p < 0.01; 0.68 ± 0.07 vs. 1.0 ± 0, p < 0.05, respectively) compared with control. Ang II-induced UB branching was abrogated by LY294002 (24 ± 2.6 vs. 37 ± 3.0, p < 0.05) or PD98059 (33 ± 2.0 vs. 48 ± 2.2, p < 0.01). These data demonstrate that Ang II-induced UB branching depends on activation of Akt and ERK1/2. We conclude that cross-talk between the RAS and c-Ret signaling plays an important role in the development of the renal collecting system.     

Electromyographic,but not mechanomyographic amplitude–force relationships,distinguished differences in voluntary activation capabilities between individuals

The purpose of the present study was to examine the influence of activation capabilities on the electromyography (EMG_RMS) and mechanomyography amplitude (MMG_RMS)–force relationships of the vastus lateralis (VL) and rectus femoris (RF). Thirteen men (mean ± SD; age = 22 ± 3 year) performed nine submaximal contractions (10–90% maximal voluntary contraction [MVC]) with the interpolated twitch technique performed during a separate contraction at 90% MVC to calculate percent voluntary activation (%VA). Nine participants with >90% VA were categorized into the high-activated group with the remaining categorized into the moderate-activated group. Slopes (b terms) were calculated from the log-transformed EMG_RMS and MMG_RMS–force relationships. The b terms (collapsed across the VL and RF) for the EMG_RMS–force relationships were greater for the high- (1.29 ± 0.31) than the moderate-activated (1.10 ± 0.20) group. In contrast, there were no differences in the b terms for the MMG_RMS–force relationships between the high- and moderate-activated groups. For the EMG_RMS and MMG_RMS–force relationships, the b terms were greater for the RF (1.38 ± 0.30, 0.81 ± 0.20) than the VL (1.08 ± 0.19, 0.60 ± 0.13) collapsed across groups. The b terms from the EMG_RMS–force relationships, but not the MMG_RMS–force relationships, reflected differences in %VA.     

Novel antioxidant bromophenols with acetylcholinesterase,butyrylcholinesterase and carbonic anhydrase inhibitory actions

In this study, a series of novel bromophenols were synthesized from benzoic acids and methoxylated bromophenols. The synthesized compounds were evaluated by using different bioanalytical antioxidant assays including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS⁺) radical scavenging assays. Also, reducing power of novel bromophenols were evaluated by Cu²⁺-Cu⁺ reducing, Fe³⁺-Fe²⁺ reducing and [Fe³⁺-(TPTZ)₂]³⁺-[Fe²⁺-(TPTZ)₂]₂+ reducing and ferrous ions (Fe²⁺) chelating abilities. The compounds demonstrate powerful antioxidant activities when compared to standard antioxidant molecules of α-tocopherol, trolox, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT). Also in the last part of this studies novel bromophenols were tested against some metabolic enzymes including acetylcholinesterase (AChE), butyrylcholinesterase (BChE) enzymes and carbonic anhydrase I, and II (hCA I and hCA II) isoenzymes. The newly synthesized bromophenols showed Ki values in a range of 6.78 ± 0.68 to 126.07 ± 35.6 nM against hCA I, 4.32 ± 0.23 to 72.25 ± 12.94 nM against hCA II, 4.60 ± 1.15 to 38.13 ± 5.91 nM against AChE and 7.36 ± 1.31 to 29.38 ± 3.68 nM against BChE.     

Coumarin-thiazole and -oxadiazole derivatives: Synthesis,bioactivity and docking studies for aldose/aldehyde reductase inhibitors

In continuation of our previous efforts directed towards the development of potent and selective inhibitors of aldose reductase (ALR2), and to control the diabetes mellitus (DM), a chronic metabolic disease, we synthesized novel coumarin-thiazole 6(a–o) and coumarin-oxadiazole 11(a–h) hybrids and screened for their inhibitory activity against aldose reductase (ALR2), for the selectivity against aldehyde reductase (ALR1). Compounds were also screened against ALR1. Among the newly designed compounds, 6c, 11d, and 11g were selective inhibitors of ALR2. Whereas, (E)-3-(2-(2-(2-bromobenzylidene)hydrazinyl)thiazol-4-yl)-2H-chromen-2-one 6c yielded the lowest IC₅₀ value of 0.16 ± 0.06 μM for ALR2. Moreover, compounds (E)-3-(2-(2-benzylidenehydrazinyl)thiazol-4-yl)-2H-chromen-2-one (6a; IC₅₀ = 2.94 ± 1.23 μM for ARL1 and 0.12 ± 0.05 μM for ARL2) and (E)-3-(2-(2-(1-(4-bromophenyl)ethylidene)hydrazinyl)thiazol-4-yl)-2H-chromen-2-one (6e; IC₅₀ = 1.71 ± 0.01 μM for ARL1 and 0.11 ± 0.001 μM for ARL2) were confirmed as dual inhibitors. Furthermore, compounds 6i, 6k, 6m, and 11b were found to be selective inhibitors for ALR1, among which (E)-3-(2-(2-((2-amino-4-chlorophenyl)(phenyl)methylene)hydrazinyl)thiazol-4-yl)-2H-chromen-2-one (6m) was most potent (IC₅₀ = 0.459 ± 0.001 μM). Docking studies performed using X-ray structures of ALR1 and ALR2 with the given synthesized inhibitors showed that coumarinyl thiazole series lacks the carboxylate function that could interact with the anionic binding site being a common ALR1/ALR2 inhibitors trait. Molecular docking study with dual inhibitor 6e also suggested plausible binding modes for the ALR1 and ALR2 enzymes. Hence, the results of this study revealed that coumarinyl thiazole and oxadiazole derivatives could act as potential ALR1/ALR2 inhibitors.