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CYP5122A1, an enzyme involved in sterol biosynthesis in Leishmania, was recently characterized as a sterol C4-methyl oxidase. Screening of a library of compounds against CYP5122A1 and CYP51 from Leishmania resulted in the identification of two structurally related classes of inhibitors of these enzymes. Analogs of screening hit N-(3,5-dimethylphenyl)-4-(pyridin-4-ylmethyl)piperazine-1-carboxamide (4a) were generally strong inhibitors of CYP51 but were less potent against CYP5122A1 and typically displayed weak inhibition of L. donovani promastigote growth. Analogs of screening hit N-(4-(benzyloxy)phenyl)-4-(2-(pyridin-4-yl)ethyl)piperazine-1-carboxamide (18a) were stronger inhibitors of both CYP5122A1 and L. donovani promastigote proliferation but also remained selective for inhibition of CYP51. Two compounds in this series, N-(4-((3,5-bis(trifluoromethyl)benzyl)oxy)phenyl)-4-(2-(pyridin-4-yl)ethyl)piperazine-1-carboxamide (18e) and N-(4-((3,5-di-tert-butylbenzyl)oxy)phenyl)-4-(2-(pyridin-4-yl)ethyl)piperazine-1-carboxamide (18i) showed modest selectivity for inhibiting L. donovani promastigote proliferation compared to J774 macrophages and were effective against intracellular L. donovani with EC 50 values in the low micromolar range. Replacement of the 4-pyridyl ring present in 18e with imidazole resulted in a compound (4-(2-(1H-imidazol-1-yl)ethyl)-N-(4-((3,5-bis(trifluoromethyl)benzyl)oxy)phenyl)piperazine-1-carboxamide, 18p) with approximately fourfold selectivity for CYP5122A1 over CYP51 that inhibited both enzymes with IC 50 values ≤ 1 µM, although selective potency against L. donovani promastigotes was lost. Compound 18p also inhibited the proliferation of L. major promastigotes and caused the accumulation of 4-methylated sterols in L. major membranes, indicating that this compound blocks sterol demethylation at the 4-position in Leishmania parasites. The molecules described here may therefore be useful for the future identification of dual inhibitors of CYP51 and CYP5122A1 as potential antileishmanial drug candidates and as probes to shed further light on sterol biosynthesis in Leishmania and related parasites., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Karl Werbovetz has patent #WO2024059333A1 pending to Ohio State Innovation Foundation, University of Kansas. Pankaj Sharma has patent #WO2024059333A1 pending to Ohio State Innovation Foundation, University of Kansas. Chris La Rosa has patent #WO2024059333A1 pending to Ohio State Innovation Foundation, University of Kansas. Michael Zhuo Wang has patent #WO2024059333A1 pending to Ohio State Innovation Foundation, University of Kansas. Yiru Jin has patent #WO2024059333A1 pending to Ohio State Innovation Foundation, University of Kansas. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Fungal infections present a significant health risk, particularly in immunocompromised individuals. Berberine, a natural isoquinoline alkaloid, has demonstrated broad-spectrum antimicrobial activity, though its antifungal potential and underlying mechanisms against both yeast-like and filamentous fungi are not fully understood. This study investigates the antifungal efficacy of berberine against Candida albicans , Cryptococcus neoformans , Trichophyton rubrum , and Trichophyton mentagrophytes in vitro, as well as its therapeutic potential in a murine model of cryptococcal infection. Berberine showed strong antifungal activity, with MIC values ranging from 64 to 128 µg/mL. SEM and TEM analyses revealed that berberine induced notable disruptions to the cell wall and membrane in C. neoformans . No signs of cell necrosis or apoptosis were observed in fungal cells treated with 2 × MIC berberine, and it did not increase intracellular ROS levels or affect mitochondrial membrane potential. Molecular docking and binding affinity assays demonstrated a strong interaction between berberine and the fungal enzyme CYP51, with a dissociation constant (KD) of less than 1 × 10 -12 M, suggesting potent inhibition of ergosterol biosynthesis. In vivo studies further showed that berberine promoted healing in guinea pigs infected with T. mentagrophytes , and in a murine cryptococcal infection model, it prolonged survival and reduced lung inflammation, showing comparable efficacy to fluconazole. These findings indicate that berberine exerts broad-spectrum antifungal effects through membrane disruption and CYP51 inhibition, highlighting its potential as a promising therapeutic option for fungal infections.

In the present work, a new class of thiazole-isatin-1,2,3-triazole hybrids (5 a-5 p) and precursor alkyne hybrids (6 a-6 d) has been reported with their in-silico studies. After structural identifications using different spectroscopic technique such as FTIR, 1 H and 13 C NMR and HRMS, the synthesized hybrids were explored for their biological potential using molecular docking and molecular dynamics calculations. Molecular docking results revealed that compound 5 j showed maximum binding energy i. e. -10.3 and -12.6 kcal/mol against antibacterial and antifungal enzymes; 1KZN (E. coli) and 5TZ1 (C. albicans), respectively. Molecular dynamics simulations for the best molecule (100 ns) followed by PBSA calculations suggested a stable complex of 5 j with 5TZ1 with binding energy of -118.760 kJ/mol as compared to 1KZN (-94.593 kJ/mol). The mean RMSD values for the 1KZN with 5 j complex remained approximately 0.175 nm throughout all the time span of 100 ns in the production stages and is in the acceptable range. Whereas, 5TZ1 with 5 j complex, RMSD values exhibited variability within the range of 0.15-0.25 nm., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

The present study aimed to investigate the antifungal activity of citronellal (CIT) against clinical isolates of T. rubrum and to show the possible mechanism of action involved. The antifungal potential of CIT was evaluated from the Minimum Inhibitory Concentration (MIC), Minimum Fungicide Concentration (MFC) and assays with ergosterol and sorbitol, to elucidate the possible mechanisms of action, and molecular docking. MIC and MFC values ranged from 4 to 512 µg/mL. Regarding the mechanism of action, the monoterpene demonstrated interaction with fungal ergosterol. In addition, it is possible to observe that CIT acts on crucial enzymes for the biosynthesis and maintenance of the fungal cell membrane, due to the ability of the monoterpene to bind to CYP51. The results obtained in this research demonstrate that CIT has the potential to become, in the future, a product for the treatment of dermatophytosis.

In our previous study, coumarin-containing CYP51 inhibitor A32 demonstrated potent antiresistance activity. However, compound A32 demonstrated unsatisfied metabolic stability, necessitating modifications to overcome these limitations. In this study, α,β-unsaturated amides were used to replace the unstable coumarin ring, which increased metabolic stability by four times while maintaining antifungal activity, including activity against resistant strains. Subsequently, the sterol composition analysis and morphological observation experiments indicated that the target of these novel compounds is lanosterol 14α-demethylase (CYP51). Meanwhile, biofilm growth was inhibited and resistance genes ( ERG11 , CDR1 , CDR2 , and MDR1 ) expression was downregulated to find out how the antiresistance works. Importantly, compound C07 demonstrated the capacity to stimulate reactive oxygen species, thus displaying potent fungicidal activity. Moreover, C07 exhibited encouraging effectiveness in vivo following intraperitoneal administration. Additionally, the most potent compound C07 showed satisfactory pharmacokinetic properties and low toxicity. These α,β-unsaturated amide derivatives, particularly C07 , are potential candidates for treating azole-resistant candidiasis.

Fungal infections maintain a close relation with the body's immune function. In this study, three series of benzazole compounds were designed as dual-target (PD-L1/CYP51) inhibitors using the skeleton splicing approach; their molecular structures were synthesized and evaluated accordingly. Among them, the compounds 9a-2 , 12a-2 , and 12b-1 exhibited potent antifungal activity and dual-target inhibition ability. Especially, the compound 12a-2 simultaneously exerted excellent bifunctional effects of fungal inhibition and immune activation. Moreover, a layered double hydroxide (LDH) carrier was also successfully constructed based on an infection microenvironment to improve the bioavailability and the targeting of compound 12a-2 . This significantly accelerated the recovery process of deep and shallow fungal infections. In conclusion, this study expanded the development horizon of antifungal drugs and provided a novel drug delivery route for treating fungal infections.

The drugs fighting against aggressive fungal infections are in limited number, therefore, extensive research is obligatory to develop new therapeutic strategies. Fluconazole (FLZ) is a clinically approved drug, but resistant drug against most fungal pathogens, thus it is vital to identify more compounds that can better check the fungal growth. Analogue-based drug designing is a quick and economical way since it has inherent drug-like properties of marketed drugs. This study aims to generate and evaluate analogues of FLZ with better potency against fungal-borne infections. A total of 3307 analogues of FLZ were developed from six scaffold structures. Only 390 compounds passed Lipinski's rule, of which 247 analogues exhibited lower docking scores than FLZ with 5FSA. These inhibitors were further subjected to pharmacokinetics property evaluation and cytotoxicity test and it was found that only 46 analogues were suitable for further evaluation. Based on the molecular docking score of the best two analogues, 6f (-12.7 kcal/mol) and 8f (-12.8 kcal/mol) were selected for molecular dynamics and in-vitro studies. Antifungal activities of both compounds against 4 strains of Candida albicans were evaluated by disc diffusion assay and micro broth dilution assay and Minimum inhibitory concentrations (MICs) for 6f and 8f were observed as 256 µg/ml against 4719, 4918 and 5480 strains but the MIC was extended to 512 µg/ml for strain 3719. Both analogues exhibited low antifungal activities as compared to FLZ (8-16 µg/ml). The interaction of 6f with Mycostatin was also performed using a chequerboard assay that was found additive.Communicated by Ramaswamy H. Sarma.

Thirty-four new pyrido[4,3- d ]pyrimidine analogs were designed, synthesized, and characterized. The crystal structures for compounds 2c and 4f were measured by means of X-ray diffraction of single crystals. The bioassay results showed that most target compounds exhibited good fungicidal activities against Pyricularia oryzae , Rhizoctonia cerealis , Sclerotinia sclerotiorum , Botrytis cinerea, and Penicillium italicum at 16 μg/mL. Compounds 2l , 2m , 4f , and 4g possessed better fungicidal activities than the commercial fungicide epoxiconazole against B. cinerea . Their half maximal effective concentration (EC 50 ) values were 0.191, 0.487, 0.369, 0.586, and 0.670 μg/mL, respectively. Furthermore, the inhibitory activities of the bioactive compounds were determined against sterol 14α-demethylase (CYP51). The results displayed that they had prominent activities. Compounds 2l , 2m , 4f , and 4g also showed better inhibitory activities than epoxiconazole against CYP51. Their half maximal inhibitory concentration (IC 50 ) values were 0.219, 0.602, 0.422, 0.726, and 0.802 μg/mL, respectively. The results of molecular dynamics (MD) simulations exhibited that compounds 2l and 4f possessed a stronger affinity to CYP51 than epoxiconazole.

Faced with increasingly serious fungal infections and drug resistance issues, three different series of novel dual-target (programmed death ligand 1/14 α-demethylase) compounds were constructed through the fragment combination pathway in the study. Their chemical structures were synthesized, characterized, and evaluated. Among them, preferred compounds 10c-1 , 17b-1 , and 18b-2 could efficiently exert their antifungal and antidrug-resistant fungal ability through blocking ergosterol biosynthesis, inducing the upregulation of reactive oxygen species level, and triggering apoptosis. Especially, compound 18b-2 exhibited the synergistic function of fungal inhibition and immune activation. Moreover, the covalent organic framework carrier was also generated based on the acidic microenvironment of fungal infection to improve the bioavailability and targeting of preferred compounds; this finally accelerated the body's recovery rate.

To discover potential sterol 14α-demethylase (CYP51) inhibitors, thirty-four unreported 4 H -pyrano[3,2- c ]pyridine derivatives were designed and synthesized. The assay results indicated that most compounds displayed significant fungicidal activity against Sclerotinia sclerotiorum , Colletotrichum lagenarium , Botrytis cinerea , Penicillium digitatum , and Fusarium oxysporum at 16 μg/mL. The half maximal effective concentration (EC 50 ) values of compounds 7a , 7b , and 7f against B. cinerea were 0.326, 0.530, and 0.610, respectively. Namely, they had better antifungal activity than epoxiconazole (EC 50 = 0.670 μg/mL). Meanwhile, their half maximal inhibitory concentration (IC 50 ) values against CYP51 were 0.377, 0.611, and 0.748 μg/mL, respectively, representing that they also possessed better inhibitory activities than epoxiconazole (IC 50 = 0.802 μg/mL). The fluorescent quenching tests of proteins showed that 7a and 7b had similar quenching patterns to epoxiconazole. The molecular dynamics simulations indicated that the binding free energy of 7a and epoxiconazole to CYP51 was -35.4 and -27.6 kcal/mol, respectively.

Acanthamoeba are free-living pathogenic protozoa that cause blinding keratitis, disseminated infection, and granulomatous amebic encephalitis, which is generally fatal. The development of efficient and safe drugs is a critical unmet need. Acanthamoeba sterol 14α-demethylase (CYP51) is an essential enzyme of the sterol biosynthetic pathway. Repurposing antifungal azoles for amoebic infections has been reported, but their inhibitory effects on Acanthamoeba CYP51 enzymatic activity have not been studied. Here, we report catalytic properties, inhibition, and structural characterization of CYP51 from Acanthamoeba castellanii . The enzyme displays a 100-fold substrate preference for obtusifoliol over lanosterol, supporting the plant-like cycloartenol-based pathway in the pathogen. The strongest inhibition was observed with voriconazole (1 h IC 50 0.45 μM), VT1598 (0.25 μM), and VT1161 (0.20 μM). The crystal structures of A. castellanii CYP51 with bound VT1161 (2.24 Å) and without an inhibitor (1.95 Å), presented here, can be used in the development of azole-based scaffolds to achieve optimal amoebicidal effectiveness.

The search for new anti-infectives based on metal complexes is gaining momentum. Among the different options taken by researchers, the one involving the use of organometallic complexes is probably the most successful one with a compound, namely, ferroquine, already in clinical trials against malaria. In this study, we describe the preparation and in-depth characterization of 10 new (organometallic) derivatives of the approved antifungal drug fluconazole. Our rationale is that the sterol 14α-demethylase is an enzyme part of the ergosterol biosynthesis route in Trypanosoma and is similar to the one in pathogenic fungi. To demonstrate our postulate, docking experiments to assess the binding of our compounds with the enzyme were also performed. Our compounds were then tested on a range of fungal strains and parasitic organisms, including the protozoan parasite Trypanosoma cruzi ( T. cruzi ) responsible for Chagas disease, an endemic disease in Latin America that ranks among some of the most prevalent parasitic diseases worldwide. Of high interest, the two most potent compounds of the study on T. cruzi that contain a ferrocene or cobaltocenium were found to be harmless for an invertebrate animal model, namely, Caenorhabditis elegans ( C. elegans ), without affecting motility, viability, or development.

The design of novel dual-target (COX-2/CYP51) inhibitors was proposed in the study, and three series of compounds were constructed though the pathway of skeleton screening and combination; their molecular structures were synthesized and evaluated. Most of the compounds exhibited significant antifungal ability. Among them, potential compounds ( 10a-2 , 16b-3 ) with excellent antifungal and anti-drug-resistant fungal ability (MIC 50 , 0.125-2.0 μg/mL) were selected for the subsequent mechanistic study. On the one hand, these compounds could block the ergosterol biosynthesis pathway by inhibiting CYP51 and influence the internal physiological function of fungal cells, which included the increase of the ROS level, the anomaly of ΔΨ m , and the emergence of an apoptotic state. On the other hand, these compounds also effectively showed COX-2 inhibition ability, eliminated the inflammatory reaction of the infected region, and activated the body's immune function. In summary, this study not only provided a novel antifungal drug design pathway but also discovered excellent target compounds.

Currently, chemical agents hold great promise in preventing and combating Botrytis cinerea . However, the antifungal mechanism of some agents for B. cinerea remains rather vague, imposing restrictions on the research and development of novel antifungal inhibitors. In this work, we discovered that mulberrin (MBN), a natural compound from the root bark of Ramulus Mori , with an IC 50 of 1.38 μM together, demonstrated marked anti-14α-demethylase (CYP51) activity through high throughput virtual screening and in vitro bioactivity assay. The computational biology results demonstrated that MBN and its derivatives were bound to the catalytic activity region of CYP51, but only MBN could form a strong π-cation interaction with the Fe ion of heme in CYP51 via the 2-methylpent-2-ene moiety at atom C9. MBN had a stronger binding free energy than the other three compounds with CYP51, implying that the 2-methylpent-2-ene moiety at atom C9 is a critical pharmacophore for CYP51 inhibitors. Subsequently, through an antifungal test, MBN demonstrated excellent anti- B. cinerea activity by inhibiting CYP51 activity. The EC 50 values of MBN toward hyphal growth and spore germination in B. cinerea were 17.27 and 9.56 μg mL -1 , respectively. The bioactivity loss of CYP51 by direct interaction with MBN induced the increase of cell membrane permeability, membrane destruction, and cell death. Meanwhile, in the B. cinerea infection model, MBN significantly prolonged the preservation of strawberries by preventing B. cinerea from infecting strawberries and could be used as a potential natural preserving agent for storing fruits.

Ergosterol exert the important function in maintaining the fluidity and osmotic pressure of fungal cells, and its key biosynthesis enzymes (Squalene epoxidase, SE; 14 α-demethylase, CYP51) displayed the obvious synergistic effects. Therefore, we expected to discover the novel antifungal compounds with dual-target (SE/CYP51) inhibitory activity. In the progress, we screened the different kinds of potent fragments based on the dual-target (CYP51, SE) features, and the method of fragment-based drug discovery (FBDD) was used to guide the construction of three different series of benzodioxane compounds. Subsequently, their chemical structures were synthesized and evaluated. These compounds displayed the obvious biological activity against the pathogenic fungal strains. Notably, target compounds 10a-2 and 22a-2 possessed the excellent broad-spectrum anti-fungal activity (MIC 50 , 0.125-2.0 μg/mL) and the activity against drug-resistant strains (MIC 50 , 0.5-2.0 μg/mL). Preliminary mechanism studies have confirmed that these compounds effectively inhibited the dual-target (SE/CYP51) activity, they could cause fungal rupture and death by blocking the bio-synthetic pathway of ergosterol. Further experiments discovered that compounds 10a-2 and 22a-2 also maintained a certain of anti-fungal effect in vivo. In summary, this study not only provided the new dual-target drug design strategy and method, but also discover the potential antifungal compounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Background: Glucosinolates (β-thioglucoside-N-hydroxysulfates) are a water-soluble organic anion with sulfur- and nitrogen-containing glycosides which are found in abundance in Cruciferous plants. Ergosterol (ERG13) lanosterol-14α-demethylase protein has been targeted for inhibition studies as a key regulator enzyme of fungal membrane biosynthesis., Objectives: To understand the molecular mechanism of inhibition of Ergosterol (ERG13) lanosterol- 14α-demethylase by various phytochemicals from brassicales, i.e., glucosinolates and their potential role as putative drug molecules., Methods: In this study, in silico analyses were performed to predict the molecular basis of various glucosinolates as a potential inhibitor of lanosterol-14α-demethylase protein, which is a key regulator of fungal membrane biosynthesis and its pharmacodynamics and toxicity profile. 3d structures of various glucosinolates were retrieved from PubChem, and the target protein, lanosterol-14α-demethylase (Pdb ID- 4lxj), was retrieved from the RCSB protein data bank. Molecular docking and interactions were carried out using the PyRx software using the AutoDOCK toolbar with default parameters. Dru- LiTo, ORISIS web servers were used to predict various drug likeliness predictions and Lipinski's Rule of 5, whereas admetSAR was used for prediction of toxicity, and PASS Program was used to study the antifungal and antimicrobial properties of these compounds., Results: This study shows that among the different compounds screened, gluconasturtiin, Glucotropaeolin, and Indolylmethyl-Glucosinolate showed the highest binding energies of -8.7 kcal/mol, -8.5 kcal/mol, and -8.3 kcal/mol with the lanosterol-14α-demethylase, respectively. Further all the compounds follow the Lipinski's rule as well as they are found to be non-carcinogenic and non-cytotoxic in nature. These compounds also show antifungal properties., Conclusion: This study thus reveals that various glucosinolates interact with the ERG13 enzyme at various amino acid positions, which behaves as a catalytic site, thus indicates the probable mechanism of inactivation, and subsequently, these can be used as potential drug molecules. In vitro studies can be taken to further examine the utility of these compounds as antifungal agents., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Chagas disease kills over 10,000 people per year, and approximately 8 million people are infected by Trypanosoma cruzi. The reference drug for treatment of the disease, benznidazole, is the same since the 70s. In recent years, many CYP51 inhibitors were tested against this parasite's target. One of them, posaconazole, was even tested in clinical trials that unfortunately were not successful. Nevertheless, there are still many evidences that CYP51 is a great potential target to treat T. cruzi infection. The research for new effective molecules that can cure the chronic phase of the disease is essential. 2D and 3D-quantitative structure activity relationship (QSAR) studies were conducted in this work to create three QSAR models using the chemical structures of 197 published compounds that already went through either in vivo or in vitro tests. After the analysis of the models, new analogues not yet synthesized were suggested here and had their biological activity and synthetic availability assessed., (© 2020. Springer Nature Switzerland AG.)

Invasive fungal infections remain a challenge due to lack of effective antifungal agents and serious drug resistance. Discovery of antifungal agents with novel antifungal mechanism is important and urgent. Previously, we designed the first CYP51/HDAC dual inhibitors with potent activity against resistant Candida albicans infections. To better understand the antifungal spectrum and synergistic mechanism, herein new CYP51/HDAC dual inhibitors were designed which showed potent in vitro and in vivo antifungal activity against C. neoformans and C. tropicalis infections. Antifungal mechanism studies revealed that the CYP51/HDAC dual inhibitors acted by inhibiting various virulence factors of C. tropicalis and C. neoformans and down-regulating resistance-associated genes. This study highlights the potential of CYP51/HDAC dual inhibitors as a promising strategy for the discovery of novel broad-spectrum antifungal agents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

A series of selenium-containing miconazole derivatives were identified as potent antifungal drugs in our previous study. Representative compound A03 (MIC = 0.01 μg/mL against C.alb. 5314) proved efficacious in inhibiting the growth of fungal pathogens. However, further study showed lead compound A03 exhibited potential hemolysis, significant cytotoxic effect and unfavorable metabolic stability and was therefore modified to overcome these drawbacks. In this article, the further optimization of selenium-containing miconazole derivatives resulted in the discovery of similarly potent compound B17 (MIC = 0.02 μg/mL against C.alb. 5314), exhibiting a superior pharmacological profile with decreased rate of metabolism, cytotoxic effect and hemolysis. Furthermore, compound B17 showed fungicidal activity against Candida albicans and significant effects on the treatment of resistant Candida albicans infections. Meanwhile, compound B17 not only could reduce the ergosterol biosynthesis pathway by inhibiting CYP51, but also inhibited biofilm formation. More importantly, compound B17 also shows promising in vivo efficacy after intraperitoneal injection and the PK study of compound B17 was evaluated. In addition, molecular docking studies provide a model for the interaction between the compound B17 and the CYP51 protein. Overall, we believe that these selenium-containing miconazole compounds can be further developed for the potential treatment of fungal infections., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Lead optimization generates selenium-containing miconazole CYP51 inhibitors with improved pharmacological profile for the treatment of fungal infections” for possible publication in “European Journal of Medicinal Chemistry”., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

In order to assess safety and efficacy of small molecule drugs as well as agrochemicals, it is key to understanding the nature of protein-ligand interaction on an atomistic level. Prothioconazole (PTZ), although commonly considered to be an azole-like inhibitor of sterol 14-α demethylase (CYP51), differs from classical azoles with respect to how it binds its target. The available evidence is only indirect, as crystallographic elucidation of CYP51 complexed with PTZ have not yet been successful. We derive a binding mode hypothesis for PTZ binding its target, compare to DPZ, a triazole-type metabolite of PTZ, and set our findings into context of its biochemistry and spectroscopy. Quantum Theory of Atoms in Molecules (QTAIM) analysis of computed DFT electron densities is used to qualitatively understand the topology of binding, revealing significant differences of how R- and S-enantiomers are binding and, in particular, how the thiozolinthione head of PTZ binds to heme compared to DPZ's triazole head. The difference of binding enthalpy is calculated at coupled cluster (DLPNO-CCSD(T)) level of theory, and we find that DPZ binds stronger to CYP51 than PTZ by more than ΔH ~ 11 kcal/mol.

The in vitro antimicrobial properties of some chalcones (1A-1C: ) and chalcone tethred 1,4-disubstituted 1,2,3-triazoles (2A-2U: ) towards different microbial strains viz. Staphylococcus aureus , Bacillus subtilis , Escherichia coli , Pseudomonas aeruginosa , Aspergillus niger and Candida albicans are reported. Compounds 2G: and 2U: exhibited better potency than the standard Fluconazole with MIC values of 0.0063 µmol/mL and 0.0068 µmol/mL, respectively. Furthermore, molecular docking was performed to investigate the binding modes of two potent compounds 2Q: and 2G: with E. coli topoisomerase II DNA gyrase B and C. albicans lanosterol 14α-demethylase, respectively. Based on these results, a statistically significant quantitative structure activity relationship (QSAR) model was successfully summarized for antibacterial activity against B. subtilis ., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

1,2,3-Triazole, a five-membered heterocyclic nucleus, is widely recognized as a key chromophore of great value in medicinal chemistry for delivering compounds possessing innumerable biological activities, including antimicrobial, antitubercular, antidiabetic, antiviral, antitumor, antioxidants, and anti-inflammatory activities. Mainly, in the past years, diverse conjugates carrying this biologically valuable core have been reported due to their attractive fungicidal potential and potent effects on various infective targets. Hence, hybridization of 1,2,3-triazole with other antimicrobial pharmacophores appears to be a judicious strategy to develop new effective anti-fungal candidates to combat the emergence of drug-sensitive and drug-resistant infectious diseases. Thus, the current review highlights the recent advances of this promising category of 1,2,3-triazole-containing hybrids incorporating diverse varieties of bioactive heterocycles such as conozole, coumarin, imidazole, benzimidazole, pyrazole, indole, oxindole, chromene, pyrane, quinazoline, chalcone, isoflavone, carbohydrates, and amides. It underlies their inhibition behavior against a wide array of infectious fungal species during 2015-2020., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Trypanosomatidae family belongs to the Kinetoplastida order, which consists of obligatory parasites that affect plants and all classes of vertebrates, especially humans and insects. Among the heteroxenic parasites, Leishmania spp., Trypanosoma cruzi, and T. brucei are protozoa of most significant interest for medicinal chemistry, being etiological agents of Leishmaniasis, Chagas, and Sleep Sickness diseases, respectively. Currently, inefficient pharmacotherapy, especially in chronic phases and low selectivity towards parasite/host cells, justifies the need to discover new drugs to treat them effectively. Among other targets, the sterol 14α-demethylase (CYP51), an enzyme responsible for ergosterol's biosynthesis in Trypanosomatidae parasites, has received more attention in the development of new bioactive compounds. In this context, antifungal ravuconazole proved to be the most promising drug among this class against T. cruzi, being used in combined therapy with Bnz in clinic trials. Non-antifungal inhibitors, such as VFV and VNF, have shown promising results against T. cruzi and T.brucei, respectively, being tested in Bnz-combined therapies. Among the experimental studies involving azoles, compound (15) was found to be the most promising derivative, displaying an IC50 value of 0.002 μM against amastigotes from T. cruzi, in addition to being non-toxic and highly selective towards TcCYP51 (< 25 nM). Interestingly, imidazole analog (16) was active against infectious forms of these three parasites, demonstrating Ki values of 0.17, 0.02, and 0.36 nM for CYP51 from T. cruzi, T. brucei, and L. infantum. Finally, this review will address promising inhibitors targeting sterol 14α-demethylase (CYP51) from Trypanosomatidae parasites, highlighting SAR studies, interactions with this target, and recent contributions and advances in the field, as well., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

7H-Benzo[7,8]chromeno[2,3-d]pyrimidin-9(8H)-amine (6a,b) have been synthesized via hydrazinolysis of the imidates (5a,b). Polysubstituted chromenotriazolopyrimidine (7a-j), (12a,b) and Schiff base (8a,b) derivatives have also been prepared. The new heterocyclic derivatives were affirmed by spectral data. The target compounds have been screened for antibacterial and antifungal activity. Compounds 6a,b and 7a-c, g,h displayed the most favorable antimicrobial activities in resemblance to the reference antimicrobial agents by IZ range over 24 mm. In addition, MIC, MBC and MFC were also tested and screen for most active compound 6a by 6.25 µg/mL showing bactericidal effect. SAR study revealed that the antimicrobial vitality of the target compounds was safely influenced by the lipophilicity substituents and the calculated log P value. The potent compounds were subjected into in vitro enzyme screening (14α-Demethylase and DNA Gyrase) against both interesting targets and showed good inhibitory profile. Molecular modeling analyses were introduced and discussed focusing on the docking of active compounds into two essential targets, and their ADMET properties were studied., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Ergosterol as the core component of fungal cell membrane plays a key role in maintaining cell morphology and permeability. The squalenee epoxidase (SE) and 14-demethylase (CYP51) are the important rate-limiting enzymes for ergosterol synthesis. In the study, these active fragments, which is derived from the structural groups of the common antifungal agents, were docked into the active sites of dual targets (SE, CYP51), respectively. Some of active fragments with the matching MCSS&#95;Score values were selected and connected to construct three different series of novel arylalkene-amide derivatives as dual-target (SE, CYP51) antifungal inhibitors. Subsequently, these compounds were further synthesized, and their bioactivity was evaluated. Most of compounds showed a certain degree of antifungal activity in vitro. It was worth noting that the target compounds 17a and 25a with excellent antifungal activity (0.125-4 μg/mL) can inhibit the fluconazole-resistant Candida Strain 17#, CaR, 632, and 901 in the range of MIC values (4-8 μg/mL). Furthermore, their molecular mechanism, structural stability and low toxicity were further confirmed. The molecular docking and ADMET properties were predicted to guide the subsequent optimization of target compounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Masson SAS.)

Candida species cause an opportunistic yeast infection called Candidiasis, which is responsible for more than 50,000 deaths every year around the world. Effective treatments against candidiasis caused by non-albicans Candida species such as C. glabrata, C. parapsilosis, C. aureus, and C. krusei are limited due to severe resistance to conventional antifungal drugs. Natural drimane sesquiterpenoids have shown promising antifungal properties against Candida yeast and have emerged as valuable candidates for developing new candidiasis therapies. In this work, we isolated isodrimeninol ( C1 ) from barks of Drimys winteri and used it as starting material for the hemi-synthesis of four sesquiterpenoids by oxidation with pyridinium chlorochromate (PCC). The structure of the products ( C2 , C3 , C4, and C5 ) was elucidated by 1D and 2D NMR spectroscopy resulting in C4 being a novel compound. Antifungal activity assays against C. albicans, C. glabrata, and C. krusei revealed that C4 exhibited an increased activity (IC 50 of 75 μg/mL) compared to C1 (IC 50 of 125 μg/mL) in all yeast strains. The antifungal activity of C1 and C4 was rationalized in terms of their capability to inhibit lanosterol 14-alpha demethylase using molecular docking, molecular dynamics simulations, and MM/GBSA binding free energy calculations. In silico analysis revealed that C1 and C4 bind to the outermost region of the catalytic site of 14-alpha demethylase and block the entrance of lanosterol ( LAN ) to the catalytic pocket. Binding free energy estimates suggested that C4 forms a more stable complex with the enzyme than C1 , in agreement with the experimental evidence. Based on this new approach it is possible to design new drimane-type sesquiterpenoids for the control of Candida species as inhibitors of 14-alpha demethylase.

Fungal infections are a global issue affecting over 150 million people worldwide annually, with 750 000 of these caused by invasive Candida infections. Azole drugs are the frontline treatment against fungal infections; however, resistance to current azole antifungals in C. albicans poses a threat to public health. Two series of novel azole derivatives, short and extended derivatives, have been designed, synthesised and investigated for CYP51 inhibitory activity, binding affinity and minimum inhibitory concentration (MIC) against C. albicans strains. The short derivatives were more potent against the C. albicans strains (e. g., MIC 2-(4-chlorophenyl)-N-(2,4-dichlorobenzyl)-3-(1H-imidazol-1-yl)propanamide (5 f) <0.03 μg/mL, N-(4-((4-chlorophenyl)sulfonamido)benzyl)-2-phenyl-3-(1H-1,2,4-triazol-1-yl)propanamide (12 c), 1 μg/mL, fluconazole 0.125 μg/mL) but both displayed comparable enzyme binding and inhibition (5 f K d 62±17 nM, IC 50 0.46 μM; 12 c K d 43±18 nM, IC 50 0.33 μM, fluconazole K d 41±13 nM, IC 50 0.31 μM, posaconazole K d 43±11 nM, IC 50 0.2 μM). The short series had poor selectivity for CaCYP51 over the human homologue, whereas the selectivity of the extended series, for example, compound 12 c, was higher (21.5-fold) than posaconazole (4.7-fold) based on K d values, although posaconazole was more selective (615-fold) than 12 c (461-fold) based on IC 50 values. Based on inhibitory activity and selectivity profile, the extended series are the better of the two series for further development., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Invasive fungal infections (particularly candidiasis) are emerging as severe infectious diseases worldwide. Because of serious antifungal drug resistance, therapeutic efficacy of the current treatment for candidiasis is limited and associated with high mortality. However, it is highly challenging to develop novel strategies and effective therapeutic agents to combat drug resistance. Herein, the first generation of lanosterol 14α-demethylase (CYP51)-histone deacetylase (HDAC) dual inhibitors was designed, which exhibited potent antifungal activity against azole-resistant clinical isolates. In particular, compounds 12h and 15j were highly active both in vitro and in vivo to treat azole-resistant candidiasis. Antifungal mechanism studies revealed that they acted by blocking ergosterol biosynthesis and HDAC catalytic activity in fungus, suppressing the function of efflux pump, yeast-to-hypha morphological transition, and biofilm formation. Therefore, CYP51-HDAC dual inhibitors represent a promising strategy to develop novel antifungal agents against azole-resistant candidiasis.

The fungal diseases represent an increasing global health burden and have transformed from a rare curiosity to the leading cause of human mortality. The present manuscript reports the antifungal potential of two novel compounds possessing a carbohydrate and an imidazole moiety. Antifungal susceptibility test determined the growth inhibition potential of the synthesized compounds against Aspergillus niger 9689 and it was observed that compounds D and E gave an antifungal inhibitory index of 66.66 and 56.67% respectively. Further, ultra-structure analysis of the treated fungal mycelia through scanning electron microscope (SEM) and confocal microscopy indicated significant membrane permeability and disintegration of fungal cell membrane, thus highlighting the probable role of the synthesized compounds as inhibitors of fungal lanosterol 14α-demethylase. In silico studies corroborated with the in-vitro results, as the synthesized compounds interacted with the critical amino acids present at the active site of the fungal enzyme (lanosterol 14α-demethylase)., (Copyright © 2019. Published by Elsevier Masson SAS.)

The cytochrome P450 enzyme lanosterol 14α-demethylase (LDM) is the target of the azole antifungals used widely in medicine and agriculture as prophylaxis or treatments of infections or diseases caused by fungal pathogens. These drugs and agrochemicals contain an imidazole, triazole or tetrazole substituent, with one of the nitrogens in the azole ring coordinating as the sixth axial ligand to the LDM heme iron. Structural studies show that this membrane bound enzyme contains a relatively rigid ligand binding pocket comprised of a deeply buried heme-containing active site together with a substrate entry channel and putative product exit channel that reach to the membrane. Within the ligand binding pocket the azole antifungals have additional affinity determining interactions with hydrophobic side-chains, the polypeptide backbone and via water-mediated hydrogen bond networks. This review will describe the tools that can be used to identify and characterise the next generation of antifungals targeting LDM, with the goal of obtaining highly potent broad-spectrum fungicides that will be able to avoid target and drug efflux mediated antifungal resistance., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Imidazole containing compounds have been a very much explored field since ancient times. Subsequently, it constitutes a significant moiety for the new drug development. A variety of compounds having imidazole moiety have been synthesized, evaluated and marketed for the treatment of various diseases such as antifungal, antiepileptic, ACE inhibitors and so on, as shown in the figure. The search for imidazole containing compounds with more selective biological potency with low side effects continues to be an active area of research in medicinal chemistry. This review is in an effort to highlight the marketed drugs with imidazole ring. The article also demonstrates the future prospective of marketed imidazoles as antifungal with potential activity targeting 14α-demethylase enzyme., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Imidazole is one of the most explored and marketed azole utilized for the treatment of fungal infections. Lanosterol 14α-demethylase (Cytochrome P450DM) is the active target site for azole antifungals., Aim and Objective: This study emphasized on evaluation of a series of halogenated imidazole analogues using molecular docking studies for anti-Candidal activity. Furthermore, the model was refined by molecular dynamic simulation., Methods: Halogenated imidazole analogues (PS1-PS30) were obtained from literature for the study. The imidazole analogues were prepared using Chem sketch and molecular docking was performed using Molergo Virtual Docker program and ADMET study was carried out by using Accelry's Accord for Excel programme., Results: The docking study indicated that all the imidazole analogues (PS1-PS30) and standard drugs i.e., Ketoconazole, Miconazole and Clotrimazole possessed interaction with protein residue, heme cofactor and water molecule positioned above Heme cofactor of 14α-demethylase. Further, the ADMET study indicated that most of the halogenated imidazoles possessed good absorption, human intestinal absorption, aqueous solubility and blood brain penetration., Conclusion: Halogenated imidazole analogues may be used as potential lead molecules as 14α- demethylase inhibitors., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Sterol 14α-demethylases (CYP51) are the cytochrome P450 enzymes required for biosynthesis of sterols in eukaryotes, the major targets for antifungal agents and prospective targets for treatment of protozoan infections. Human CYP51 could be and, for a while, was considered as a potential target for cholesterol-lowering drugs (the role that is now played by statins, which are also in clinical trials for cancer) but revealed high intrinsic resistance to inhibition. While microbial CYP51 enzymes are often inhibited stoichiometrically and functionally irreversibly, no strong inhibitors have been identified for human CYP51. In this study, we used comparative structure/functional analysis of CYP51 orthologs from different biological kingdoms and employed site-directed mutagenesis to elucidate the molecular basis for the resistance of the human enzyme to inhibition and also designed, synthesized, and characterized new compounds. Two of them inhibit human CYP51 functionally irreversibly with their potency approaching the potencies of azole drugs currently used to inhibit microbial CYP51.

Aim: The global burden of fungal infections has transitioned from a case-specific observation to a major cause of high human mortality. Therefore, novel compounds with innovative methodologies need to be synthesized and evaluated for their antifungal potential to keep pace with the current clinical demands. Results: An efficient synthetic pathway was developed for the synthesis of 21 synthetic novel nucleosides. Two compounds had significant antifungal effect on Aspergillus fumigatus 3007, which was comparable to fluconazole. The experimental data (confocal microscopy, ultrahigh-performance liquid chromatography and flow cytometry) demonstrated the inhibition of fungal lanosterol 14α-demethylase. Conclusion: Owing to the therapeutic relevance of the synthesized nucleosides and simplicity of the procedure, the method may find its potential application for synthesis of antifungal agents.

Small molecules that promote oligodendrocyte formation have been identified in "drug repurposing" screens to nominate candidate therapeutics for diseases in which myelin is lost, including multiple sclerosis. We recently reported that many such molecules enhance oligodendrocyte formation not by their canonical targets but by inhibiting a narrow range of enzymes in cholesterol biosynthesis. Here we identify enhancers of oligodendrocyte formation obtained by screening a structurally diverse library of 10,000 small molecules. Identification of the cellular targets of these validated hits revealed a majority inhibited the cholesterol biosynthesis enzymes CYP51, TM7SF2, or EBP. In addition, evaluation of analogs led to identification of CW3388, a potent EBP-inhibiting enhancer of oligodendrocyte formation poised for further optimization., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Up to now, no vaccines are available for Chagas disease, and the current therapy is largely unsatisfactory. Novel imidazole-based scaffolds of protozoan sterol 14α-demethylase (CYP51) inhibitors have demonstrated potent antiparasitic activity with no acute toxicity. Presently our aim was to investigate the effectiveness of the experimental 14α-demethylase inhibitor VFV in the mouse models of Trypanosoma cruzi infection using a naturally drug-resistant Colombiana strain, under monotherapy and in association with the reference drug, benznidazole (Bz). The treatment with VFV resulted in complete parasitemia suppression and 100% animal survival when administered orally (given in 10% DMSO plus 5% Arabic gum) at 25 mg/kg (bid) for 60 days. However, as parasite relapse was found using VFV alone under this treatment scheme, the coadministration of VFV with Bz was assayed giving simultaneously (for 60 days, bid) by oral route, under two different drug vehicles (10% DMSO plus 5% Gum Arabic with or without 3% Tween 80). All tested mice groups resulted in >99.9% of parasitemia decrease and 100% animal survival. qPCR analysis performed on cyclophosphamide immunosuppressed mice revealed that, although presenting lack of cure, VFV given as monotherapy was 14-fold more active than Bz, and the coadministration of Bz plus VFV (given simultaneously, using 10% DMSO plus 5% Gum Arabic as vehicle) resulted in 106-fold lower blood parasitism as compared to the monotherapy of Bz. Another interesting finding was the parasitological cure in 70% of the animals treated with Bz and VFV when the coadministration was given using the VFV suspension in 10% DMSO + Arabic gum + Tween 80 (a formulation that we have found to provide a better pharmacokinetics), even after immunosuppression using cyclophosphamide cycles, supporting the promising aspect of the drug coadministration in improving the efficacy of therapeutic arsenal against T. cruzi.

Background: Imidazoles are considered as potent antimicrobial agents. In view of this 2-mercaptoimidazoles were synthesized and evaluated for antimicrobial study., Methods: Some new 2-mercaptoimidazoles 4a-r were synthesized using substituted aniline and substituted phenacyl bromides in the presence of anhydrous sodium carbonate or potassium carbonate and potassium thiocyanate under solvent-free conditions catalyzed by eco-friendly ptoluene sulfonic acid., Results: The structure of compounds was evaluated on the basis of Infrared spectroscopy (IR), 1HNMR (proton nuclear magnetic resonance) and mass spectral studies. These novel compounds were screened for in-vitro antibacterial and antifungal potency against Staphyllococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger. Further, the study was rationalized by molecular modeling studies. All the compounds were subjected to molecular modeling studies for inhibition of enzyme 14α-demethylase., Conclusions: The compounds were found to be effective in inhibiting the growth of pathogens. The in-silico results depicted that, all the synthesized compounds have minimum binding energy and good affinity towards the active site and thus can be considered as good inhibitors of 14α- demethylase enzyme., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Sterol 14α-demethylases (CYP51) are cytochrome P450 enzymes essential for sterol biosynthesis in eukaryotes and therapeutic targets for antifungal azoles. Multiple attempts to repurpose antifungals for treatment of human infections with protozoa (Trypanosomatidae) have been undertaken, yet so far none of them have revealed sufficient efficacy. VNI and its derivative VFV are two potent experimental inhibitors of Trypanosomatidae CYP51, effective in vivo against Chagas disease, visceral leishmaniasis, and sleeping sickness and currently under consideration as antiprotozoal drug candidates. However, VNI is less potent against Leishmania and drug-resistant strains of Trypanosoma cruzi and VFV, while displaying a broader spectrum of antiprotozoal activity, and is metabolically less stable. In this work we have designed, synthesized, and characterized a set of close analogues and identified two new compounds (7 and 9) that exceed VNI/VFV in their spectra of antiprotozoal activity, microsomal stability, and pharmacokinetics (tissue distribution in particular) and, like VNI/VFV, reveal no acute toxicity.

A molecular design approach was used in our laboratory to guide the development of imidazole-based fungicides. Based on homology modeling and molecular docking studies targeting the cytochrome P450-dependent sterol 14α-demethylase, 3,4-dichloroisothiazole-based imidazoles showed great potential. Several such compounds were then rationally designed, synthesized, characterized, and their antifungal activities were evaluated. Bioassay results showed that compounds such as ( R)-11, ( R)-12, and ( S)-11 have commendable, broad-spectrum antifungal activities that are comparable to those of commercial products. Based on Q-PCR testing and microscopy observations, the imidazole derivatives affect fungal cell wall formation through the inhibition of the BcCYP51 expression system. These findings strongly suggest that the mode of action of these imidazole compounds is similar to that of tioconazole and imazalil. This report indicates that this molecular design strategy is not only practical but productive.

Sterol 14α-demethylase (SDM) is essential for sterol biosynthesis and is the primary molecular target for clinical and agricultural antifungals. SDM has been demonstrated to be a valid drug target for antiprotozoal therapies, and much research has been focused on using SDM inhibitors to treat neglected tropical diseases such as human African trypanosomiasis (HAT), Chagas disease, and leishmaniasis. Sterol C24-methyltransferase (24-SMT) introduces the C24-methyl group of ergosterol and is an enzyme found in pathogenic fungi and protozoa but is absent from animals. This difference in sterol metabolism has the potential to be exploited in the development of selective drugs that specifically target 24-SMT of invasive fungi or protozoa without adversely affecting the human or animal host. The synthesis and biological activity of SDM and 24-SMT inhibitors are reviewed herein.

Because of the increase in the number of immunocompromised patients, the incidence of invasive fungal infections is growing, but the treatment efficiency remains unacceptably low. The most potent clinical systemic antifungals (azoles) are the derivatives of two scaffolds: ketoconazole and fluconazole. Being the safest antifungal drugs, they still have shortcomings, mainly because of pharmacokinetics and resistance. Here, we report the successful use of the target fungal enzyme, sterol 14α-demethylase (CYP51), for structure-based design of novel antifungal drug candidates by minor modifications of VNI [( R)- N-(1-(2,4-dichlorophenyl)-2-(1 H-imidazol-1-yl)ethyl)-4-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamide)], an inhibitor of protozoan CYP51 that cures Chagas disease. The synthesis of fungi-oriented VNI derivatives, analysis of their potencies to inhibit CYP51s from two major fungal pathogens ( Aspergillus fumigatus and Candida albicans), microsomal stability, effects in fungal cells, and structural characterization of A. fumigatus CYP51 in complexes with the most potent compound are described, offering a new antifungal drug scaffold and outlining directions for its further optimization.

Novel imidazole-based ketene dithioacetals show impressive in planta activity against the economically important plant pathogens Alternaria solani, Botryotinia fuckeliana, Erysiphe necator and Zymoseptoria tritici. Especially derivatives of the topical antifungal lanoconazole, which bear an alkynyloxy or a heteroaryl group in the para-position of the phenyl ring, exhibit excellent control of the mentioned phytopathogens. These compounds inhibit 14α -demethylase in the sterol biosynthesis pathway of the fungi. Synthesis routes starting from either benzaldehydes or acetophenones as well as structure-activity relationships are discussed in detail., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

American trypanosomiasis or Chagas disease (CD) is a vector borne pathology caused by the parasite Trypanosoma cruzi (T. cruzi), which remains a serious global health problem. The current available treatment for CD is limited to two nitroderivatives with limited efficacy and several side effects. The rational design of ergosterol synthetic route inhibitors (e.g. CYP51 inhibitors) represents a promising strategy for fungi and trypanosomatids, exhibiting excellent anti-T.cruzi activity in pre-clinical assays. In the present work, we evaluate through different approaches (molecular docking, structure activity relationships, CYP51 inhibitory assay, and phenotypic screenings in vitro and in vivo) the potency and selectivity of a novel CYP51 inhibitor (compound 1) and its analogues against T.cruzi infection. Regarding anti-parasitic effect, compound 1 was active in vitro with EC 50 3.86 and 4.00 μM upon intracellular (Tulahuen strain) and bloodstream forms (Y strain), respectively. In vivo assays showed that compound 1 reduced in 43% the parasitemia peak but, unfortunately failed to promote animal survival. In order to promote an enhancement at the potency and pharmacological properties, 17 new analogues were purchased and screened in vitro. Our findings demonstrated that five compounds were active against intracellular forms, highlighting compounds 1e and 1f, with EC 50 2.20 and 2.70 μM, respectively, and selectivity indices (SI) = 50 and 36, respectively. Against bloodstream trypomastigotes, compound 1f reached an EC 50 value of 20.62 μM, in a similar range to Benznidazole, but with low SI (3). Although improved the solubility of compound 1, the analogue 1f did not enhance the potency in vitro neither promote better in vivo efficacy against mouse model of acute T.cruzi infection arguing for the synthesis of novel pyrazolo[3,4-e][1,4]thiazepin derivatives aiming to contribute for alternative therapies for CD., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

The extensive use of fluconazole (FLC) and other azole drugs has caused the emergence and rise of azole-resistant fungi. The fungistatic nature of FLC in combination with toxicity concerns have resulted in an increased demand for new azole antifungal agents. Herein, we report the synthesis and antifungal activity of novel alkylated piperazines and alkylated piperazine-azole hybrids, their time-kill studies, their hemolytic activity against murine erythrocytes, as well as their cytotoxicity against mammalian cells. Many of these molecules exhibited broad-spectrum activity against all tested fungal strains, with excellent minimum inhibitory concentration (MIC) values against non-albicans Candida and Aspergillus strains. The most promising compounds were found to be less hemolytic than the FDA-approved antifungal agent voriconazole (VOR). Finally, we demonstrate that the synthetic alkylated piperazine-azole hybrids do not function by fungal membrane disruption, but instead by disruption of the ergosterol biosynthetic pathway via inhibition of the 14α-demethylase enzyme present in fungal cells.

With the abuse of clinical broad-spectrum antimicrobial agents, immunosuppressive agents, chemotherapy drugs, the emergence of pathogenic fungi resistance is more and more frequent. However, there is still no effective treatment for the fungal resistance. Squalenee epoxidase (SE) and 14 α-demethylase (CYP51) are important antifungal drug targets. In order to achieve a deeper insight into the structural characteristics and the action modes of SE and CYP51inhibitors, the homology model of SE (Candida albicans) was constructed using monooxygenase of Pseudomonas aeruginosa as template, and the reliability of model was confirmed by Ramachandran plots and Verify 3D. Subsequently, the molecular superimposition and molecular docking were performed, and the pharmacophore model based on the CYP51 receptor structure was constructed. The results indicate that SE and CYP51 inhibitors have common structural feature with two parts of essential fragments, which are mainly composed of aromatic groups. In addition, the fragment structures of inhibitors are combined in the similar hydrophobic pockets through the hydrophobic forces. The present study provides a deeper perspective to understand the characteristics and docking modes of SE and CYP51 inhibitors. It can be used to guide the optimization and design of SE and CYP51 inhibitors. In addition, it also provides the oretical support for the development of dual target antifungal inhibitors (SE and CYP51), which can help us solve the problem of fungi resistance., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The soil amoebae Acanthamoeba causes Acanthamoeba keratitis, a severe sight-threatening infection of the eye and the almost universally fatal granulomatous amoebic encephalitis. More effective treatments are required. Sterol biosynthesis has been effectively targeted in numerous fungi using azole compounds that inhibit the cytochrome P450 enzyme sterol 14α-demethylase. Herein, using Gas Chromatography Mass Spectrometry (GCMS), we demonstrate that the major sterol of Acanthamoeba castellanii is ergosterol and identify novel putative precursors and intermediate sterols in its production. Unlike previously reported, we find no evidence of 7-dehydrostigmasterol or any other phytosterol in Acanthamoeba. Of five azoles tested, we demonstrate that tioconazole and voriconazole have the greatest overall inhibition for all isolates of Acanthamoeba castellanii and Acanthamoeba polyphaga tested. While miconazole and sulconazole have intermediate activity econazole is least effective. Through GCMS, we demonstrate that voriconazole inhibits 14α-demethylase as treatment inhibits the production of ergosterol, but results in the accumulation of the lanosterol substrate. These data provide the most complete description of sterol metabolism in Acanthamoeba, provide a putative framework for their further study and validate 14α-demethylase as the target for azoles in Acanthamoeba.

While the orally-active azoles such as fluconazole and posaconazole are effective antifungal agents, they potently inhibit a broad range of off-target human cytochrome P450 enzymes (CYPs) leading to various safety issues (e.g., drug-drug interactions, liver, and reproductive toxicities). Recently we described the rationally-designed, antifungal agent VT-1161 that is more selective for fungal CYP51 than related human CYP enzymes such as CYP3A4. Herein, we describe the use of a homology model of Aspergillus fumigatus to design and optimize a novel series of highly selective, broad spectrum fungal CYP51 inhibitors. This series includes the oral antifungal VT-1598 that exhibits excellent potency against yeast, dermatophyte, and mold fungal pathogens., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The azole antifungal drugs are an important class of chemotherapeutic agents with broad-spectrum of activity against yeasts and filamentous fungi, act in the ergosterol biosynthetic pathway through inhibition of the cytochrome P450-dependent enzyme sterol 14α-demethylase. Azole antifungals have also been repurposed for treatment of tropical protozoan infections including human leishmaniasis. Recent advances in molecular biology and computational chemistry areas have increased our knowledge about sterol biochemical pathway in Leishmania parasites. Based on the importance of sterol biosynthetic pathway in Leishmania parasites, we reviewed all studies reported on azoles for potential antileishmanial therapy along their structural and biological aspects. This review may help medicinal chemists for design of new azole-derived antileishmanial drugs., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Candida albicans infections and their resistance to clinically approved azole drugs are major concerns for human. The azole antifungal drugs inhibit the ergosterol synthesis by targeting lanosterol 14α-demethylase of cytochrome P450 family. The lack of high-resolution structural information of fungal pathogens has been a barrier for the design of modified azole drugs. Thus, a preliminary theoretical molecular dynamic study is carried out to develop and validate a simple homologous model using crystallographic structure of the lanosterol 14α-demethylase of Mycobacterium tuberculosis (PDB ID-1EA1) in which the active site residues are substituted with that of C. albicans (taxid 5476). Further, novel designed pyrazole analogs (SGS1-16) docked on chimeric 1EA1 and revealed that SGS-16 show good binding affinity through non-bonding interaction with the heme, which is different from the leading azole antifungals. The ADME-T results showed these analogs can be further explored in design of more safe and effective antifungal agents.