In silico Design, Synthesis and Biological Evaluation of Novel Thieno[3,2-d]pyrimidine Derivatives for Cancer Therapy - A Preliminary Study on the Inhibitory Potential towards ATR Kinase Domain and PIKK Family.

Continuing our studies in the field of new heterocyclic compounds with biological interest, herein we report the synthesis and anticancer activity of new N- and S-substituted derivatives of tetracyclic pyrido[3',2' : 4,5]thieno[3,2-d]pyrimidines. In this regard, starting from the thieno[2,3-b]pyridine-2-carboxylates, the corresponding 8(9)-aminopyrido[3',2' : 4,5]thieno[3,2-d]pyrimidin-7(8)-ones, as well as chloro derivatives were obtained. Based on the latter, amino, hydrazino and S-alkyl derivatives of pyrido[3',2' : 4,5]thieno[3,2-d]pyrimidines were synthesized subsequently. The current study focuses on identifying the potential of thieno[3,2-d]pyrimidine derivatives primarily towards ATR kinase inhibition, through computational predictions, followed by synthesis and cancer cell viability studies, along with an aim to develop the core as PIKK inhibitors for cancer therapy.

Substituted furan sulfonamides as carbonic anhydrase inhibitors: Synthesis, biological and in silico studies.

Carbonic Anhydrases (CAs) are a large family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide involved in several of biological processes, such as respiration, calcification, acid-base balance, bone resorption, and the formation of aqueous humor, cerebrospinal fluid, saliva, and gastric acid. They show wide diversity in tissue distribution and in their subcellular localization. Fifteen novel furyl sulfonamides were designed, synthesized and evaluated against four human isoforms: hCA I, hCA II, hCA IV and hCA IX. Compounds appeared to be very active mostly against hCAI (8) and hCA IV (11) isoforms being more potent than reference drug acetazolamide (AAZ). It should be mentioned that four compounds were more active than AAZ against hCA IX isoform, with compound 13d to be selective against hCA I (SI 70), hCA II (SI 13.5) and hCA IV (SI 20). Furthermore, docking was performed for some of these compounds on all isoforms I order to understand the possible interactions with the active site. The most active compounds showed good bioavailability and drug likeness scores.

Synthesis, Biological and In Silico Studies of Griseofulvin and Usnic Acid Sulfonamide Derivatives as Fungal, Bacterial and Human Carbonic Anhydrase Inhibitors.

Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the essential reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho-/physiological conditions. A series of griseofulvin and usnic acid sulfonamides were synthesized and tested as possible CA inhibitors. Since ß- and γ- classes are expressed in microorganisms in addition to the α- class, showing substantial structural differences to the human isoforms they are also interesting as new antiinfective targets with a different mechanism of action for fighting the emerging problem of extensive drug resistance afflicting most countries worldwide. Griseofulvin and usnic acid sulfonamides were synthesized using methods of organic chemistry. Their inhibitory activity, assessed against the cytosolic human isoforms hCA I and hCA II, the transmembrane hCA IX as well as ß- and γ-CAs from different bacterial and fungal strains, was evaluated by a stopped-flow CO2 hydrase assay. Several of the investigated derivatives showed interesting inhibition activity towards the cytosolic associate isoforms hCA I and hCA II, as well as the three γ-CAs and Malassezia globosa (MgCA) enzyme. Six compounds (1b-1d, 1h, 1i and 1j) were more potent than AAZ against hCA I while five (1d, 1h, 1i, 1j and 4a) showed better activity than AAZ against the hCA II isoform. Moreover, all compounds appeared to be very potent against MgCA with a Ki lower than that of the reference drug. Furthermore, computational procedures were used to investigate the binding mode of this class of compounds within the active site of human CAs.

Discovery of Novel EGFR Inhibitor Targeting Wild-Type and Mutant Forms of EGFR: In Silico and In Vitro Study.

Targeting L858R/T790M and L858R/T790M/C797S mutant EGFR is a critical challenge in developing EGFR tyrosine kinase inhibitors to overcome drug resistance in non-small cell lung cancer (NSCLC). The discovery of next-generation EGFR tyrosine kinase inhibitors (TKIs) is therefore necessary. To this end, a series of furopyridine derivatives were evaluated for their EGFR-based inhibition and antiproliferative activities using computational and biological approaches. We found that several compounds derived from virtual screening based on a molecular docking and solvated interaction energy (SIE) method showed the potential to suppress wild-type and mutant EGFR. The most promising PD13 displayed strong inhibitory activity against wild-type (IC50 of 11.64 ± 1.30 nM), L858R/T790M (IC50 of 10.51 ± 0.71 nM), which are more significant than known drugs. In addition, PD13 revealed a potent cytotoxic effect on A549 and H1975 cell lines with IC50 values of 18.09 ± 1.57 and 33.87 ± 0.86 µM, respectively. The 500-ns MD simulations indicated that PD13 formed a hydrogen bond with Met793 at the hinge region, thus creating excellent EGFR inhibitory activity. Moreover, the binding of PD13 in the hinge region of EGFR was the major determining factor in stabilizing the interactions via hydrogen bonds and van der Waals (vdW). Altogether, PD13 is a promising novel EGFR inhibitor that could be further clinically developed as fourth-generation EGFR-TKIs.

New Bicyclic Pyridine-Based Hybrids Linked to the 1,2,3-Triazole Unit: Synthesis via Click Reaction and Evaluation of Neurotropic Activity and Molecular Docking.

The synthesis of new original bicyclic pyridine-based hybrids linked to the 1,2,3-triazole unit was described via a click reaction. The anticonvulsant activity and some psychotropic properties of the new compounds were evaluated. The biological assays demonstrated that some of the studied compounds showed high anticonvulsant and psychotropic properties. The five most active compounds (7a, d, g, j, and m) contain a pyrano [3,4-c]pyridine cycle with a methyl group in the pyridine ring in their structures. Furthermore, molecular docking studies were performed, and their results are in agreement with experimental data.

Synthesis of 1-Amino-3-oxo-2,7-naphthyridines via Smiles Rearrangement: A New Approach in the Field of Chemistry of Heterocyclic Compounds.

In this paper we describe an efficient method for the synthesis of new heterocyclic systems: furo[2,3-c]-2,7-naphthyridines 6, as well as a new method for the preparation of 1,3-diamino-2,7-naphthyridines 11. For the first time, a Smiles rearrangement was carried out in the 2,7-naphthyridine series, thus gaining the opportunity to synthesize 1-amino-3-oxo-2,7-naphthyridines 4, which are the starting compounds for obtaining furo[2,3-c]-2,7-naphthyridines. The cyclization of alkoxyacetamides 9 proceeds via two different processes: the expected formation of furo[2,3-c]-2,7-naphthyridines 10 and the 'unexpected' formation of 1,3-diamino-2,7-naphthyridines 11 (via a Smiles type rearrangement).

Benzothiazole and Chromone Derivatives as Potential ATR Kinase Inhibitors and Anticancer Agents.

Despite extensive studies and the great variety of existing anticancer agents, cancer treatment remains an aggravating and challenging problem. Therefore, the development of novel anticancer drugs with a better therapeutic profile and fewer side effects to combat this persistent disease is still necessary. In this study, we report a novel series of benzothiazole and chromone derivatives that were synthesized and evaluated for their anticancer activity as an inhibitor of ATR kinase, a master regulator of the DDR pathway. The cell viability of a set of 25 compounds was performed using MTT assay in HCT116 and HeLa cell lines, involving 72 h incubation of the compounds at a final concentration of 10 µM. Cells incubated with compounds 2c, 7h and 7l were found to show viability ≤50%, and were taken forward for dose-response studies. Among the tested compounds, three of them (2c, 7h and 7l) showed higher potency, with compound 7l exhibiting the best IC50 values in both the cell lines. Compounds 2c and 7l were found to be equally cytotoxic towards both the cell lines, namely, HCT116 and HeLa, while compound 7h showed better cytotoxicity towards HeLa cell line. For these three compounds, an immunoblot assay was carried out in order to analyze the inhibition of phosphorylation of Chk1 at Ser 317 in HeLa and HCT116 cells. Compound 7h showed inhibition of pChk1 at Ser 317 in HeLa cells at a concentration of 3.995 µM. Further analysis for Chk1 and pChk1 expression was carried out in Hela cells by treatment against all the three compounds at a range of concentrations of 2, 5 and 10 µM, wherein compound 7h showed Chk1 inhibition at 2 and 5 µM, while pChk1 expression was observed for compound 7l at a concentration of 5 µM. To support the results, the binding interactions of the compounds with the ATR kinase domain was studied through molecular docking, wherein compounds 2c, 7h and 7l showed binding interactions similar to those of Torin2, a known mTOR/ATR inhibitor. Further studies on this set of molecules is in progress for their specificity towards the ATR pathway.

Synthesis, Biological Evaluation and Molecular Docking Studies of 5-Indolylmethylen-4-oxo-2-thioxothiazolidine Derivatives.

BACKGROUND: Infectious diseases represent a significant global strain on public health security and impact on socio-economic stability all over the world. The increasing resistance to the current antimicrobial treatment has resulted in the crucial need for the discovery and development of novel entities for the infectious treatment with different modes of action that could target both sensitive and resistant strains. METHODS: Compounds were synthesized using the classical organic chemistry methods. Prediction of biological activity spectra was carried out using PASS and PASS-based web applications. Pharmacophore modeling in LigandScout software was used for quantitative modeling of the antibacterial activity. Antimicrobial activity was evaluated using the microdilution method. AutoDock 4.2® software was used to elucidate probable bacterial and fungal molecular targets of the studied compounds. RESULTS: All compounds exhibited better antibacterial potency than ampicillin against all bacteria tested. Three compounds were tested against resistant strains MRSA, P. aeruginosa and E. coli and were found to be more potent than MRSA than reference drugs. All compounds demonstrated a higher degree of antifungal activity than the reference drugs bifonazole (6-17-fold) and ketoconazole (13-52-fold). Three of the most active compounds could be considered for further development of the new, more potent antimicrobial agents. CONCLUSION: Compounds 5b (Z)-3-(3-hydroxyphenyl)-5-((1-methyl-1H-indol-3-yl)methylene)-2-thioxothiazolidin-4-one and 5g (Z)-3-[5-(1H-Indol-3-ylmethylene)-4-oxo-2-thioxo-thiazolidin-3-yl]-benzoic acid as well as 5h (Z)-3-(5-((5-methoxy-1H-indol-3-yl)methylene)-4-oxo-2-thioxothiazolidin-3-yl)benzoic acid can be considered as lead compounds for further development of more potent and safe antibacterial and antifungal agents.

Antibacterial activity of noscapine analogs.

The antibacterial properties of close noscapine analogs have not been previously reported. We used our pDualrep2 double-reporter High Throughput Screening (HTS) platform to identify a series of noscapine derivatives with promising antibacterial activity. The platform is based on RPF (SOS-response/DNA damage) and Katushka2S (inhibition of translation) proteins and simultaneously provides information on antibacterial activity and the mechanism of action of small-molecule compounds against E. coli. The most potent compound exhibited an MIC of 13.5 µM(6.25 µg/ml) and a relatively low cytotoxicity against HEK293 cells (CC50 = 71 µM, selectivity index: ~5.5). Some compounds from this series induced average Katushka2S reporter signals, indicating inhibition of translation machinery in the bacteria; however, these compounds did not attenuate translation in vitro in a luciferase-based translation assay. The most effective compounds did not significantly arrest the mitotic cycle in HEK293 cells, in contrast to the parent compound in a flow cytometry assay. Several molecules showed activity against clinically relevant gram-negative and gram-positive bacterial strains. Compounds from the discovered series can be reasonably regarded as good templates for further development and evaluation.

Synthesis and antimicrobial activity of new 2-piperazin-1-yl-N-1,3-thiazol-2-ylacetamides of cyclopenta[c]pyridines and pyrano[3,4-c]pyridines.

In this study, we report the synthesis and antimicrobial activity of some new disubstituted piperazines. Thus, 3-chlorocyclopenta[c]pyridines and 6-chloropyrano[3,4-c]pyridine 1 under mild reaction conditions with piperazine gave the 3(6)-piperazine-substituted cyclopenta[c]pyridines and pyrano[3,4-c]pyridine 2. Furthermore, the latter, by alkylation with 2-chloro-N-1,3-thiazol-2-ylacetamide, led to the formation of the target compounds. The evaluation of the antibacterial activity revealed that 3k was the most potent compound. The most sensitive bacterium was found to be Listeria monocytogenes, whereas Staphylococcus aureus was the most resistant one. Three compounds, 3d, 3g, and 3k, were tested also against the following resistant strains: methicillin-resistant S. aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa. All three compounds appeared to be more potent than ampicillin against MRSA. Moreover, compound 3d showed a better activity than the reference drug ampicillin against P. aeruginosa, whereas 3g was more efficient against E. coli. The best antifungal activity was observed again for compound 3k. The most resistant fungi appeared to be Aspergillus fumigatus, whereas Trichoderma viride seemed the most sensitive one toward the compounds tested. Molecular docking studies on E. coli MurB, as well as on Candida albicans CYP51 and dihydrofolate reductase, were used for the prediction of the mechanisms of the antibacterial and antifungal activities, confirming the experimental results.

Chromene-Containing Aromatic Sulfonamides with Carbonic Anhydrase Inhibitory Properties.

Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the essential reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho/physiological conditions. A series of chromene-based sulfonamides were synthesized and tested as possible CA inhibitors. Their inhibitory activity was assessed against the cytosolic human isoforms hCA I, hCA II and the transmembrane hCA IX and XII. Several of the investigated derivatives showed interesting inhibition activity towards the tumor associate isoforms hCA IX and hCA XII. Furthermore, computational procedures were used to investigate the binding mode of this class of compounds, within the active site of hCA IX.

Disruption of the Complex between GAPDH and Hsp70 Sensitizes C6 Glioblastoma Cells to Hypoxic Stress.

Hypoxia, which commonly accompanies tumor growth, depending on its strength may cause the enhancement of tumorigenicity of cancer cells or their death. One of the proteins targeted by hypoxia is glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and we demonstrated here that hypoxia mimicked by treating C6 rat glioblastoma cells with cobalt chloride caused an up-regulation of the enzyme expression, while further elevation of hypoxic stress caused the enzyme aggregation concomitantly with cell death. Reduction or elevation of GAPDH performed with the aid of specific shRNAs resulted in the augmentation of the tumorigenicity of C6 cells or their sensitization to hypoxic stress. Another hypoxia-regulated protein, Hsp70 chaperone, was shown to prevent the aggregation of oxidized GAPDH and to reduce hypoxia-mediated cell death. In order to release the enzyme molecules from the chaperone, we employed its inhibitor, derivative of colchicine. The compound was found to substantially increase aggregation of GAPDH and to sensitize C6 cells to hypoxia both in vitro and in animals bearing tumors with distinct levels of the enzyme expression. In conclusion, blocking the chaperonic activity of Hsp70 and its interaction with GAPDH may become a promising strategy to overcome tumor resistance to multiple environmental stresses and enhance existing therapeutic tools.

Carbonic Anhydrase Inhibition with Sulfonamides Incorporating Pyrazole- and Pyridazinecarboxamide Moieties Provides Examples of Isoform-Selective Inhibitors.

A series of benzenesulfonamides incorporating pyrazole- and pyridazinecarboxamides decorated with several bulky moieties has been obtained by original procedures. The new derivatives were investigated for the inhibition of four physiologically crucial human carbonic anhydrase (hCA, EC 4.2.2.1.1) isoforms, hCA I and II (cytosolic enzymes) as well as hCA IX and XII (transmembrane, tumor-associated isoforms). Examples of isoform-selective inhibitors were obtained for all four enzymes investigated here, and a computational approach was employed for explaining the observed selectivity, which may be useful in drug design approaches for obtaining inhibitors with pharmacological applications useful as antiglaucoma, diuretic, antitumor or anti-cerebral ischemia drugs.

Synthesis and Neurotropic Activity of New Heterocyclic Systems: Pyridofuro[3,2-d]pyrrolo[1,2-a]pyrimidines, Pyridofuro[3,2-d]pyrido[1,2-a]pyrimidines and Pyridofuro[3',2':4,5]pyrimido[1,2-a]azepines.

BACKGROUND: Neurotic disturbances, anxiety, neurosis-like disorders, and stress situations are widespread. Benzodiazepine tranquillizers have been found to be among the most effective antianxiety drugs. The pharmacological action of benzodiazepines is due to their interaction with the supra-molecular membrane GABA-a-benzodiazepine receptor complex, linked to the Cl-ionophore. Benzodiazepines enhance GABA-ergic transmission and this has led to a study of the role of GABA in anxiety. The search for anxiolytics and anticonvulsive agents has involved glutamate-ergic, 5HT-ergic substances and neuropeptides. However, each of these well-known anxiolytics, anticonvulsants and cognition enhancers (nootropics) has repeatedly been reported to have many adverse side effects, therefore there is an urgent need to search for new drugs able to restore damaged cognitive functions without causing significant adverse reactions. OBJECTIVE: Considering the relevance of epilepsy diffusion in the world, we have addressed our attention to the discovery of new drugs in this field Thus our aim is the synthesis and study of new compounds with antiepileptic (anticonvulsant) and not only, activity. METHODS: For the synthesis of compounds classical organic methods were used and developed. For the evaluation of biological activity some anticonvulsant and psychotropic methods were used. RESULTS: As a result of multistep reactions 26 new, five-membered heterocyclic systems were obtained. PASS prediction of anticonvulsant activity was performed for the whole set of the designed molecules and probability to be active Pa values were ranging from 0.275 to 0.43. The studied compounds exhibit protection against pentylenetetrazole (PTZ) seizures, anti-thiosemicarbazides effect as well as some psychotropic effect. The biological assays evidenced that some of the studied compounds showed a high anticonvulsant activity by antagonism with pentylenetetrazole. The toxicity of compounds is low and they do not induce muscle relaxation in the studied doses. According to the study of psychotropic activity it was found that the selected compounds have an activating behavior and anxiolytic effects on the models of "open field" and "elevated plus maze" (EPM). The data obtained indicate the anxiolytic (anti-anxiety) activity of the derivatives of pyrimidines, especially pronounced in compounds 6n, 6b, and 7c. The studied compounds increase the latent time of first immobilization on the model of "forced swimming" (FST) and exhibit some antidepressant effect similarly to diazepam. Docking studies revealed that compound 6k bound tightly in the active site of GABAA receptor with a value of the scoring function that estimates free energy of binding (ΔG) at -7.95 kcal/mol, while compound 6n showed the best docking score and seems to be dual inhibitor of SERT transporter as well as 5-HT1A receptor. CONCLUSIONS: Тhe selected compounds have an anticonvulsant, activating behavior and anxiolytic effects, at the same time exhibit some antidepressant effect.

Identification of pyrrolo-pyridine derivatives as novel class of antibacterials.

A series of 5-oxo-4H-pyrrolo[3,2-b]pyridine derivatives was identified as novel class of highly potent antibacterial agents during an extensive large-scale high-throughput screening (HTS) program utilizing a unique double-reporter system-pDualrep2. The construction of the reporter system allows us to perform visual inspection of the underlying mechanism of action due to two genes-Katushka2S and RFP-which encode the proteins with different imaging signatures. Antibacterial activity of the compounds was evaluated during the initial HTS round and subsequent rescreen procedure. The most active molecule demonstrated a MIC value of 3.35 µg/mL against E. coli with some signs of translation blockage (low Katushka2S signal) and no SOS response. The compound did not demonstrate cytotoxicity in standard cell viability assay. Subsequent structural morphing and follow-up synthesis may result in novel compounds with a meaningful antibacterial potency which can be reasonably regarded as an attractive starting point for further in vivo investigation and optimization.

5-(1H-Indol-3-ylmethylene)-4-oxo-2-thioxothiazolidin-3-yl)alkancarboxylic Acids as Antimicrobial Agents: Synthesis, Biological Evaluation, and Molecular Docking Studies.

BACKGROUND: Infectious diseases symbolize a global consequential strain on public health security and impact on the socio-economic stability all over the world. The increasing resistance to the current antimicrobial treatment has resulted in crucial need for the discovery and development of novel entity for the infectious treatment with different modes of action that could target both sensitive and resistant strains. METHODS: Compounds were synthesized using classical methods of organic synthesis. RESULTS: All 20 synthesized compounds showed antibacterial activity against eight Gram-positive and Gram-negative bacterial species. It should be mentioned that all compounds exhibited better antibacterial potency than ampicillin against all bacteria tested. Furthermore, 18 compounds appeared to be more potent than streptomycin against Staphylococcus aureus, Enterobacter cloacae, Pseudomonas aeruginosa, Listeria monocytogenes, and Escherichia coli. Three the most active compounds 4h, 5b, and 5g appeared to be more potent against MRSA than ampicillin, while streptomycin did not show any bactericidal activity. All three compounds displayed better activity also against resistant strains P. aeruginosa and E. coli than ampicillin. Furthermore, all compounds were able to inhibit biofilm formation 2- to 4-times more than both reference drugs. Compounds were evaluated also for their antifungal activity against eight species. The evaluation revealed that all compounds exhibited antifungal activity better than the reference drugs bifonazole and ketoconazole. Molecular docking studies on antibacterial and antifungal targets were performed in order to elucidate the mechanism of antibacterial activity of synthesized compounds. CONCLUSION: All tested compounds showed good antibacterial and antifungal activity better than that of reference drugs and three the most active compounds could consider as lead compounds for the development of new more potent agents.

Structure of Dirithromycin Bound to the Bacterial Ribosome Suggests New Ways for Rational Improvement of Macrolides.

Although macrolides are known as excellent antibacterials, their medical use has been significantly limited due to the spread of bacterial drug resistance. Therefore, it is necessary to develop new potent macrolides to combat the emergence of drug-resistant pathogens. One of the key steps in rational drug design is the identification of chemical groups that mediate binding of the drug to its target and their subsequent derivatization to strengthen drug-target interactions. In the case of macrolides, a few groups are known to be important for drug binding to the ribosome, such as desosamine. Search for new chemical moieties that improve the interactions of a macrolide with the 70S ribosome might be of crucial importance for the invention of new macrolides. For this purpose, here we studied a classic macrolide, dirithromycin, which has an extended (2-methoxyethoxy)-methyl side chain attached to the C-9/C-11 atoms of the macrolactone ring that can account for strong binding of dirithromycin to the 70S ribosome. By solving the crystal structure of the 70S ribosome in complex with dirithromycin, we found that its side chain interacts with the wall of the nascent peptide exit tunnel in an idiosyncratic fashion: its side chain forms a lone pair-π stacking interaction with the aromatic imidazole ring of the His69 residue in ribosomal protein uL4. To our knowledge, the ability of this side chain to form a contact in the macrolide binding pocket has not been reported previously and potentially can open new avenues for further exploration by medicinal chemists developing next-generation macrolide antibiotics active against resistant pathogens.

Madumycin II inhibits peptide bond formation by forcing the peptidyl transferase center into an inactive state.

The emergence of multi-drug resistant bacteria is limiting the effectiveness of commonly used antibiotics, which spurs a renewed interest in revisiting older and poorly studied drugs. Streptogramins A is a class of protein synthesis inhibitors that target the peptidyl transferase center (PTC) on the large subunit of the ribosome. In this work, we have revealed the mode of action of the PTC inhibitor madumycin II, an alanine-containing streptogramin A antibiotic, in the context of a functional 70S ribosome containing tRNA substrates. Madumycin II inhibits the ribosome prior to the first cycle of peptide bond formation. It allows binding of the tRNAs to the ribosomal A and P sites, but prevents correct positioning of their CCA-ends into the PTC thus making peptide bond formation impossible. We also revealed a previously unseen drug-induced rearrangement of nucleotides U2506 and U2585 of the 23S rRNA resulting in the formation of the U2506•G2583 wobble pair that was attributed to a catalytically inactive state of the PTC. The structural and biochemical data reported here expand our knowledge on the fundamental mechanisms by which peptidyl transferase inhibitors modulate the catalytic activity of the ribosome.

Extending the Inhibition Profiles of Coumarin-Based Compounds Against Human Carbonic Anhydrases: Synthesis, Biological, and In Silico Evaluation.

Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the fundamental reaction of CO2 hydration in all living organisms and are actively involved in the regulation of a plethora of pathological and physiological conditions. A set of new coumarin/ dihydrocoumarin derivatives was here synthesized, characterized, and tested as human CA inhibitors. Their inhibitory activity was evaluated against the cytosolic human isoforms hCA I and II and the transmembrane hCA IX and hCA XII. Two compounds showed potent inhibitory activity against hCA IX, being more active or equipotent with the reference drug acetazolamide. Computational procedures were used to investigate the binding mode of this class of compounds within the active site of hCA IX and XII that are validated as anti-tumor targets.

Application of Docking Analysis in the Prediction and Biological Evaluation of the Lipoxygenase Inhibitory Action of Thiazolyl Derivatives of Mycophenolic Acid.

5-LOX inhibition is among the desired characteristics of anti-inflammatory drugs, while 15-LOX has also been considered as a drug target. Similarity in inhibition behavior between soybean LOX-1 and human 5-LOX has been observed and soybean LOX (sLOX) type 1b has been used for the evaluation of LOX inhibition in drug screening for years. After prediction of LOX inhibition by PASS and docking as well as toxicity by PROTOX and ToxPredict sixteen (E)-N-(thiazol-2-yl)-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydroisobenzofuran-5-yl)-4-methylhex-4-enamide derivatives with lengths varying from about 15⁻20 Å were evaluated in vitro for LOX inhibitory action using the soybean lipoxygenase sLOX 1b. Docking analysis was performed using soybean LOX L-1 (1YGE), soybean LOX-3 (1JNQ), human 5-LOX (3O8Y and 3V99) and mammalian 15-LOX (1LOX) structures. Different dimensions of target center and docking boxes and a cavity prediction algorithm were used. The compounds exhibited inhibitory action between 2.5 µΜ and 165 µΜ. Substituents with an electronegative atom at two-bond proximity to position 4 of the thiazole led to enhanced activity. Docking results indicated that the LOX structures 1JNQ, 3V99 and 1LOX can effectively be used for estimation of LOX inhibition and amino acid interactions of these compounds.