Search

Ergosterol is essential for fungal cell membrane integrity and growth, and numerous antifungal drugs target ergosterol. Inactivation or modification of ergosterol biosynthetic genes can lead to changes in antifungal drug susceptibility, filamentation and stress response. Here, we found that the ergosterol biosynthesis gene ERG251 is a hotspot for point mutations during adaptation to antifungal drug stress within two distinct genetic backgrounds of Candida albicans. Heterozygous point mutations led to single allele dysfunction of ERG251 and resulted in azole tolerance in both genetic backgrounds. This is the first known example of point mutations causing azole tolerance in C. albicans. Importantly, single allele dysfunction of ERG251 in combination with recurrent chromosome aneuploidies resulted in bona fide azole resistance. Homozygous deletions of ERG251 caused increased fitness in low concentrations of fluconazole and decreased fitness in rich medium, especially at low initial cell density. Homozygous deletions of ERG251 resulted in accumulation of ergosterol intermediates consistent with the fitness defect in rich medium. Dysfunction of ERG251, together with FLC exposure, resulted in decreased accumulation of the toxic sterol (14-ɑ-methylergosta-8,24(28)-dien-3β,6α-diol) and increased accumulation of non-toxic alternative sterols. The altered sterol composition of the ERG251 mutants had pleiotropic effects on transcription, filamentation, and stress responses including cell membrane, osmotic and oxidative stress. Interestingly, while dysfunction of ERG251 resulted in azole tolerance, it also led to transcriptional upregulation of ZRT2, a membrane-bound Zinc transporter, in the presence of FLC, and overexpression of ZRT2 is sufficient to increase azole tolerance in wild-type C. albicans. Finally, in a murine model of systemic infection, homozygous deletion of ERG251 resulted in decreased virulence while the heterozygous deletion mutants maintain their pathogenicity. Overall, this study demonstrates that single allele dysfunction of ERG251 is a recurrent and effective mechanism of acquired azole tolerance. We propose that altered sterol composition resulting from ERG251 dysfunction mediates azole tolerance as well as pleiotropic effects on stress response, filamentation and virulence.

Acquired resistance in Candida albicans brings about a serious challenge to the clinical application of azoles, so it is urgent to elucidate the mechanisms of azole resistance to improve the therapeutic efficiency. In the aim of searching for the potential targets mediating fluconazole resistance, we screened a mutant library of 48 transcription factor deletion Candida albicans strains. The screening results showed that hap2Δ/Δ mutants were significantly more susceptible to azoles, especially to miconazole (MCZ). Under MCZ treatment, the intracellular reactive oxygen species (ROS) were significantly higher in hap2Δ/Δ mutants compared to the control strain SN250. The addition of antioxidants reversed the MCZ-sensitive phenotype caused by the deletion of HAP2. Consistently, the expression of antioxidases responsible for scavenging ROS was shown to decrease in hap2Δ/Δ mutants, suggesting that the transcription factor Hap2p is involved in the regulation of oxidative stress responses in C. albicans. In addition, HAP2 deficiency also resulted in impaired mitochondrial function and affected cellular energy supply, which may be related to the iron deficiency regulated by HAP complex. HAP2 disruption also decreased efflux-mediated resistance of C. albicans, as demonstrated by a significant decrease in Cdr1p expression and a slight decrease in Mdr1p expression in hap2Δ/Δ strains under the action of MCZ. The above results indicate that the transcription factor Hap2p was required for the resistance of C. albicans to azoles, which could provide a new strategy to solve the clinical azoles resistance. [ABSTRACT FROM AUTHOR]

Background Scedosporium/Lomentospora species are ranked as the second most frequently isolated filamentous fungi from cystic fibrosis (CF) patients. Previously, we demonstrated that the minimum inhibitory concentration (MIC) for voriconazole and posaconazole increased when performed on a mucin-containing synthetic CF sputum medium (SCFM) compared to the standard medium, RPMI-1640. In this study, we have expanded the MIC comparison to four additional azoles and investigated characteristics linked to azole resistance in Scedosporium apiospermum , Scedosporium minutisporum , Scedosporium aurantiacum and Lomentospora prolificans. Methods MIC was assayed by CLSI protocol, efflux pump activity was assessed by rhodamine 6G and sterols were analysed by gas chromatography-mass spectrometry (GC-MS). Results Overall, MICs for fluconazole, itraconazole, voriconazole, posaconazole, miconazole and ketoconazole increased by least 2-fold when susceptibility tests were performed using SCFM compared to RPMI. The activity of efflux pumps was similar in both media; however, in RPMI, but not in SCFM, the activity was induced by voriconazole and fluconazole. Additionally, MICs for those antifungals decreased more noticeably in SCFM than in RPMI in the presence of the efflux pump inhibitor PaβN. The SCFM-grown cells presented fewer sterols in their composition, and consequently higher membrane fluidity, than RPMI-grown cells. GC-MS analysis demonstrated a remodulation in the sterol profile in SCFM- compared to RPMI-grown cells. Accordingly, when the MIC assay was performed in the presence of the membrane stressor NaCl (3%), the susceptibility to voriconazole and fluconazole increased more in SCFM- than RPMI-grown cells. Conclusions Scedosporium / Lomentospora species undergo cellular adaptations in SCFM that favours their growth in face of the challenges imposed by azole antifungals. [ABSTRACT FROM AUTHOR]

The azidofunctionalization of alkenes under mild conditions using commercially available starting materials and easily accessible reagents is reported based on a radical‐polar crossover strategy. A broad range of alkenes, including vinyl arenes, enamides, enol ethers, vinyl sulfides, and dehydroamino esters, were regioselectively functionalized with an azide and nucleophiles such as azoles, carboxylic acids, alcohols, phosphoric acids, oximes, and phenols. The method led to a more efficient synthesis of 1,2‐azidofunctionalized pharmaceutical intermediates when compared to previous approaches, resulting in both reduction of step count and increase in overall yield. The scope and limitations of these transformations were further investigated through a standard unbiased selection of 15 substrate combinations out of 1,175,658 possible using a clustering technique. [ABSTRACT FROM AUTHOR]

The properties (geometry, bond-dissociation enthalpies and proton affinities) of three azoles, pyrrole, imidazole and pyrazole, with twenty-two N-substituents R covering a significant part of the periodic table [1 (lithium group, alkaline), 2 (beryllium group, alkaline earth), 13 (boron group, triel), 14 (carbon group, tetrel), 15 (nitrogen group, pnictogen), 16 (oxygen group, chalcogen) and 17 (fluorine group, halogen) of the periods 2, 3 and 4 plus the hydrogen] have been calculated with the G4 composite ab initio method. These three properties were discussed with regard to the azole and to the group R using as model compound the amines H2N–R. The large set of compounds and their consistency allowed finding many equations that related different calculated properties. General properties such as bond-dissociation enthalpies, BDH, N–R bond lengths and proton affinities were tested in search of simple equations that explain the calculated properties. [ABSTRACT FROM AUTHOR]

Although the mitochondrial genome is an attribute of all eukaryotes, some yeast species (called petite-positive) can replicate without mitochondrial DNA (mtDNA). Strains without mtDNA (known as rho− mutants or petite mutants) are respiration-deficient and require fermentable carbon sources (such as glucose) for their metabolism. However, they are compromised in many aspects of fitness and competitiveness. Nevertheless, a few research groups have reported that some petite mutants of Candida glabrata and Saccharomyces cerevisiae manifested higher levels of tolerance to the antifungal fluconazole than their wild-type (WT) counterparts. In this study, we show that elevated tolerance to two or three out of four tested antifungals is a generic feature of at least five petite-positive species of yeasts including C. glabrata (higher tolerance of petites to clotrimazole and miconazole), S. bayanus (tolerance to clotrimazole, fluconazole, and miconazole), S. cerevisiae (tolerance to clotrimazole and fluconazole), S. paradoxus (tolerance to clotrimazole, fluconazole, and miconazole), and S. pastorianus (tolerance to clotrimazole and fluconazole). Comparing the levels of tolerance to the antifungals in WT and petite mutants was based on measuring the diameters of the zones of inhibition (ZOIs) using disc diffusion assays. The mode of inhibition in the majority of WT strains by all antifungals was fungicidal; most of the rho− mutants manifested fungistatic inhibition. We observed partial (not complete) inhibition in WT, with four different types of ZOI patterns that were species- and antifungal-specific. The partial inhibition was characterised by the presence of antifungal-tolerant colonies within ZOI areas. The inability of these colonies selected from ZOIs to grow on glycerol, as a single source of carbon, proved that they were rho− mutants spontaneously generated in the WT populations. The results on the elevated tolerance of petite strains to antifungals are discussed in terms of the prospective positive selection of respiratory-deficient mutants and the various implications of such selection. [ABSTRACT FROM AUTHOR]

A series of 5-oxo-1-(3,4,5-trimethoxyphenyl)pyrrolidine-3-carboxylic acid derivatives–hydrazones, N-ethylhydrazones, pyrrole, pyrazole, oxadiazole, and triazole were synthesized and evaluated for their anticancer activity using human A549 pulmonary epithelial cells (ATCC CCl-185). The in vitro viability inhibitory effects of the compounds were assessed using the MTT assay. The characterization of the anticancer activity of the synthesized compounds showed that the incorporation of 1,3,4-oxadiazolethione and 4-aminotriazolethione rings into the molecular structures obviously enhances the anticancer activity against human A549 lung epithelial cells, reducing their viability to 28.0% and 29.6%, respectively. The anticancer activity of these azole derivatives was significantly higher than that of cytarabine. Further studies are needed to better optimize 5-oxo-1-(3,4,5-trimethoxyphenyl)pyrrolidine-3-carboxylic acid derivatives and enhance their in vitro anticancer activity. [ABSTRACT FROM AUTHOR]

An efficient heterogeneous Pd/Cu synergistic catalysis system without a ligand was utilized for C–H arylation of azoles. The reaction exhibits excellent catalytic activity with high functional group tolerance. The synergistic effect between the Cu2O core and PdCu shell was confirmed, whereas pure PdCu nanocages and Cu2O exhibited negligible catalytic activity. [ABSTRACT FROM AUTHOR]

Pyrazole and tetrazole are among the most important heterocyclic members of the azole family. Over the past decade, these N-heterocycles and their derivatives have demonstrated specific properties that give them potent applications in several fields such as pharmacology, technology, and agriculture. Combining these two azoles in single hybrid architecture has given rise to highly potent molecules in terms of efficacy and specificity, with enhanced and scalable properties. In this context, the present paper deals with the literature of the last 10 years describing the synthesis protocols for pyrazole-tetrazole-based molecules. Their biological activities as well as their energetic properties are also reported. [ABSTRACT FROM AUTHOR]

Herein, we present a method for the diastereoselective synthesis of N‐heterocycle‐substituted cyclobutanes from commercially available bromocyclobutanes. This method enables the efficient formation of various heterocyclic aminocyclobutane esters and amides using simple reagents. Notably, N‐nucleophiles such as imidazoles, azoles, and nucleobase derivatives were successfully incorporated, enhancing the chemical diversity of small ring building blocks for medicinal chemistry applications. [ABSTRACT FROM AUTHOR]

Monocyclic 5‐membered heterocycles including imidazoles, thiazoles, oxazoles, and their related compounds have gained significant attention in medicinal chemistry because of their potent anticancerous activity. These small heterocyclic molecules possess versatile properties, including biological activity, absorption, distribution, metabolism, excretion, and chemical diversity that give them immense potential as anticancer agents. It is also a fact that inherent characteristic of azoles to combine with many biological molecules through hydrogen bond, stacking, and hydrophobic interaction makes them effective against almost all cancer types. In the present paper the author discusses the way which is connected with chemical structure of monocyclic azoles and their anticancer activity namely the ability of these compounds to intercalate with DNA, to inhibit some enzymes and to interfere cellular signaling pathways. Interestingly, several azole derivatives have been seen to be effective in preclinical efficacy studies as well as in clinical trials and are considered to be potent in overcoming the problem of resistance and side effects of the common anticancer agents. As the synthetic chemistry progresses, the structural system of the azoles has diversified and development in the pharmacology has become more specific. This has helped in enhancing the formation of new molecules in the azole class with improved selectivity and efficacy. Furthermore, the comprehensive review explains how computational chemistry and structure‐activity relationship (SAR) approaches are applied to the design of future‐generation azole compounds. In light of these facts, this article is designed to give a broad overview of the current state of monocyclic azole‐based anticancer agents in an attempt to further assert its therapeutic promise and spur further attempts at infusing the said agents into the cancer therapeutics fray. The discoveries made in this study may allow the development the radical different therapeutic approaches, which could lead to improved and targeted treatment of cancer. [ABSTRACT FROM AUTHOR]

Background Outpatient parenteral antimicrobial therapy (OPAT) can deliver extended parenteral treatment of fungal infections in an ambulatory setting, whilst minimizing treatment burden and cost. The extended dosing interval of rezafungin may potentiate the benefits of OPAT. Methods This retrospective cohort study includes all adult patients who received echinocandin therapy in a large OPAT programme between 2012 and 2022. Patient characteristics, treatment and outcomes were studied. Data were analysed to determine the effects of replacing daily dosing with weekly dosing of echinocandin. Results Across the study period, 11% (44/386) of all patients in our Health Service treated with ≥7 days of echinocandin were managed via OPAT. All were Candida and related 'yeast-like' species infections. Nakaseomyces glabrata (20/41; 49%) was the most common pathogen, fungaemia the most common presentation (17/41; 41%) and azole resistance the most frequent indication for echinocandin use (21/41; 51%). In total, 633 days of echinocandin were administered as OPAT. Thirteen patients (13/41; 32%) received concurrent parenteral antibacterials. Treatment success was achieved in 30/41 (73%) patients. If daily echinocandin dosing was replaced with weekly dosing, a potential 52% (633 to 326) reduction in the total number of treatments (for any therapy) delivered by the OPAT team is possible. The ongoing need for daily antibacterial administration mitigated the benefit in some of this cohort. Conclusions Echinocandin therapy can be safely delivered via OPAT with outcomes equivalent to bed-based care. The extended dosing interval of rezafungin will allow for a substantial reduction in the number of treatments required across the patient cohort. [ABSTRACT FROM AUTHOR]

The efficacy and safety of venetoclax in newly diagnosed pediatric acute myeloid leukemia (AML) are not well-established as they are in adults. Children newly diagnosed with AML were recommended for induction therapy with venetoclax and chemotherapy or hypomethylating agents (HMAs) as per for the ChiCTR1900027146 trial. Venetoclax was administered at a consistent dose of 200 mg/m2/day for 28 days, with adjustments when used concurrently with azoles. The study measured both the remission rates and the safety assessments of venetoclax. We enrolled 45 newly diagnosed pediatric patients with AML. The complete remission rates were 94.7% in the low/middle-risk group and 80.8% in the high-risk group; MRD-negative rates were 52.6% and 38.5% in the low/middle-risk group and high-risk group, respectively. Venetoclax based combination therapy was well tolerated by the majority of patients. The median duration of venetoclax dosing was 18 days (range 9–28), with hematological toxicity and infection being the most common adverse events. Venetoclax-based induction regimens demonstrated a high response rate and safety profile in newly diagnosed pediatric AML cases. This underscores the significance of venetoclax as a viable treatment option for untreated AML, extending beyond its role as salvage therapy for refractory/relapsed AML. [ABSTRACT FROM AUTHOR]

Antimicrobial drug resistance poses a global health threat, requiring a deeper understanding of the evolutionary processes that lead to its emergence in pathogens. Complex evolutionary dynamics involve multiple mutations that can result in cooperative or competitive (clonal interference) effects. Candida albicans, a major fungal pathogen, displays high rates of copy number variation (CNV) and loss of heterozygosity (LOH). CNV and LOH events involve large numbers of genes and could synergize during evolutionary adaptation. Understanding the contributions of CNV and LOH to antifungal drug adaptation is challenging, especially in the context of whole-population genome sequencing. Here, we document the sequential evolution of fluconazole tolerance and then resistance in a C. albicans isolate involving an initial CNV on chromosome 4, followed by an LOH on chromosome R that involves KSR1. Similar LOH events involving KSR1, which encodes a reductase in the sphingolipid biosynthesis pathway, were also detected in independently evolved fluconazole resistant isolates. We dissect the specific KSR1 codons that affect fluconazole resistance and tolerance. The combination of the chromosome 4 CNV and KSR1 LOH results in a >500-fold decrease in azole susceptibility relative to the progenitor, illustrating a compelling example of rapid, yet step-wise, interplay between CNV and LOH in drug resistance evolution.

Objectives: This study evaluated the role of Upc2 in the development of azole resistance in Candida albicans isolates from Lebanese hospitalized patients and determined a correlation between resistance and virulence. Methods: The UPC2 gene which codes for an ergosterol biosynthesis regulator was sequenced and analysed in two azole-resistant and one azole-susceptible C. albicans isolates. An amino acid substitution screening was carried out on Upc2 with a focus on its ligand binding domain (LBD) known to interact with ergosterol. Then, Upc2 protein secondary structure prediction and homology modelling were conducted, followed by total plasma membrane ergosterol and cell wall chitin quantifications. For virulence, mouse models of systemic infection were generated and an agar adhesion and invasion test was performed. Results: Azole-resistant isolates harboured novel amino acid substitutions in the LBD of Upc2 and changes in protein secondary structures were observed. In addition, these isolates exhibited a significant increase in plasma membrane ergosterol content. Resistance and virulence were inversely correlated while increased cell wall chitin concentration does not seem to be linked to resistance since even though we observed an increase in chitin concentration, it was not statistically significant. Conclusions: The azole-resistant C. albicans isolates harboured novel amino acid substitutions in the LBD of Upc2 which are speculated to induce an increase in plasma membrane ergosterol content, preventing the binding of azoles to their target, resulting in resistance.

The reaction of cyanogen azide with strained‐ring containing primary and secondary amines led to the isolation of energetic molecules deriving their energy content from both strained rings as well as aminotetrazoles. Azo‐coupling of these materials afforded novel high‐nitrogen energetic materials of very high sensitivity. All compounds were chemically characterized by IR, NMR, single‐crystal X‐ray crystallography, and high‐resolution mass spectrometry. Their impact and friction sensitivities were experimentally determined, and their energetic performances were calculated. [ABSTRACT FROM AUTHOR]

Background New antifungal agents are required to mitigate against azole-resistant Aspergillus and drug-resistant non- Aspergillus moulds. The novel orotomide, olorofim (F2G, Manchester, UK), has potent fungicidal activity against Aspergillus including azole-resistant Aspergillus fumigatus, Lomentospora prolificans and Scedosporium spp. Development of olorofim-specific clinical breakpoints/epidemiological cut-off values requires reliable MIC data. Objectives Determine the in vitro activity of olorofim compared with standard antifungals against mould pathogens at an Australian hospital. Materials and methods Olorofim MICs were determined for 507 clinical mould isolates using the CLSI M38-A3 standard. MICs of amphotericin B, anidulafungin, posaconazole, voriconazole and isavuconazole were obtained using Sensititre™ YeastOne YO10 and AUSNMRCI panels (Thermo-Fisher Scientific). Results A. fumigatus sensu stricto was the commonest species (33.3%) followed by L. prolificans (18.3%), Scedosporium (11.4%) and Fusarium (6%) species. Olorofim modal MICs were ≤0.25 mg/L (MIC90 0.25 mg/L) for all Aspergillus except Aspergillus Section Usti (1 mg/L); MICs for nine azole-resistant/non-wild-type A. fumigatus ranged from 0.008 to 0.125 mg/L. The MIC90 of olorofim for L. prolificans was 0.5 mg/L, 0.25–0.5 mg/L for Scedosporium spp. and 8 mg/L for the F. solani complex but with modal MICs of 0.25 and 0.008 mg/L for F. oxysporum and F. proliferatum complexes, respectively. For Verruconis gallopava (n  = 10), the olorofim MIC90 was 0.06 mg/L (voriconazole MIC90 2 mg/L, isavuconazole MICs of 4–>8 mg/L). Olorofim had little activity against other dematiaceous moulds including Exophiala species. Conclusions Olorofim was highly active against Aspergillus spp. including azole-resistant A. fumigatus , L. prolificans , Scedosporium spp. and some Fusarium species with the new finding of potent activity against V. gallopava. [ABSTRACT FROM AUTHOR]

Background: Invasive fungal disease (IFD) is a sinister complication encountered in patients with haematological disorders. When occurring in the central nervous system (CNS), IFDs can have catastrophic outcomes. Objectives: To study the clinical presentation, predisposing etiological factors, and prognosis of a CNS‐IFD in a patient with a haematological disorder. Patients and Methods: This is a retrospective study focusing on the clinical profile, diagnosis, treatment strategy and outcomes of 43 patients with an underlying haematological disorder, who were diagnosed with CNS‐IFD between 2018 and 2022. Results: Of the 43 patients, 18 were chemotherapy recipients, while 23 were stem cell transplant (SCT) recipients and 2 presented with CNS‐IFD at diagnosis. AML/MDS (37.2%) and ALL (18.6%) were the predominant underlying diagnoses. A sudden deterioration in sensorium (53.5%) was the earliest clinical sign, while T2 hyperintensities (26.8%), vascular involvement (26.8%) and ring‐enhancing lesions (16.3%) were the commonest radiological findings, with all patients exhibiting diffusion restriction in diffusion‐weighted images. Microbiological evidence of infection was obtained in all patients; however, culture positivity was established in only 25 patients. Rhizopus spp (23.2%) and Aspergillus spp (20.9%) were implicated in most cases. Overall survival of the cohort was 27.9% at a median follow‐up of 6 months. In patients who succumbed, the median time to death was 4 days (0–46). Conclusion: CNS‐IFD is associated with very poor survival in patients undergoing chemotherapy or an SCT, urging the need for prompt diagnosis and initiation of suitable antifungal therapy. [ABSTRACT FROM AUTHOR]

Candidemia is emerging as a significant concern in children, particularly among those with underlying conditions like malignancies or prematurity. The interpretation of epidemiological data on candidemias and their antifungal resistance plays a vital role in aiding diagnosis and guiding clinicians in treatment decisions. From 2014 to 2021, a retrospective analysis was conducted in İstanbul, Turkey; comparing Candida albicans and non-albicans (NAC) spp in both surviving and deceased groups. Furthermore, an examination of Candida parapsilosis and other species was performed, assessing various clinical and laboratory parameters. Among 93 patients, with a median age of 17 months, C. parapsilosis emerged as the predominant isolated species (44%), followed by C. albicans (34.4%). Resistance to fluconazole, voricanozole, and echinocandins, along with a history of broad-spectrum antibiotic use were found to be significantly higher in the non-albicans Candida group compared to C. albicans group. In the C. parapsilosis group, statistically lower age was identified in comparison to the other groups (P  = .018). In addition, high fluconazole and voriconazole resistance was detected in Candida parapsilosis spp. Our study highlights a notable prevalence of C. parapsilosis, particularly in younger children, which is different from similar studies in childhood. This trend may be attributed to the common use of total parenteral nutrition and central venous catheter in gastrointestinal disorders and metabolic diseases. Furthermore, as anticipated, high azole resistance is noted in C. parapsilosis and other non-albicans Candida species. Interestingly, resistance to both amphotericin B and echinocandins within this group has been notably high. It is crucial to emphasize the considerable antifungal resistance seen in C. parapsilosis isolates. [ABSTRACT FROM AUTHOR]

Recently, PEPPSI‐type palladium‐complexes bearing N‐heterocyclic carbene (NHC) ligand have commonly been used as the effective catalysts in the direct arylation of heteroaromatic compounds. In most of previous studies catalyzed by such complexes, unsaturated ring carbene ligands such as benzo[d]imidazol‐2‐ylidene and imidazol‐2‐ylidene were used. However, the use of saturated ring carbene ligands such as 4,5‐dihydro‐imidazol‐2‐ylidene has been highly limited. Therefore, in this study, four novel 4,5‐dihydro‐1H‐imidazolium salts were synthesized as saturated ring carbene precursors. Then, well‐defined air‐ and moisture‐stable four novel PEPPSI‐type palladium‐complexes with 4,5‐dihydro‐imidazol‐2‐ylidene ligands were prepared. All synthesized carbene precursors and palladium‐complexes were structurally characterized by different spectroscopic and analytical techniques. Further structural characterization of two of the palladium‐complexes was performed by single‐crystal X‐ray diffraction. Next, the palladium‐complexes were tested in the direct arylation of azoles such as 4,5‐dimethylthiazole and 1‐methyl‐1H‐imidazole with (hetero)aryl halides in presence of 1 mol% catalyst loading at 120°C. The results showed that these novel palladium complexes are effective catalysts. [ABSTRACT FROM AUTHOR]

This research focused on the synthesis and analysis of two novel Ru(II)-based complexes, cis-[RuCl(Hind)(phen)2]PF6 (FOR022) and cis-[Ru(Hind)2(phen)2](PF6)2 (FOR0E2), where Hind represents indazole and phen stands for 1,10-phenanthroline. These compounds were thoroughly characterized using various methods such as elemental analysis, spectroscopy techniques, and electrochemistry assay, confirming their structures. The research highlights the effectiveness of the compound FOR0E2 in exhibiting strong cytotoxic properties against various tumor cell lines, including HCT116, HepG2, HL-60, LNcaP, and PC-3, with half-maximal inhibitory concentration (IC50) values ranging from 10.7 to 25.2 μmol L−1. Additionally, FOR0E2 showed substantial leishmanicidal capabilities against both the promastigote and amastigote forms of L. amazonensis, with IC50 values of 5.7 μmol L−1 and 1.6 μmol L−1, respectively. These outcomes suggest that the inclusion of indazole in FOR022 and FOR0E2 significantly enhances their biological effectiveness, positioning it as a promising candidate for pharmacological treatments. [ABSTRACT FROM AUTHOR]

A new approach to the alkylation of azoles with alkenes catalyzed by the nickel complexes with N-heterocyclic carbenes (Ni/NHC) was developed. The catalytically active Ni/NHC complexes are formed in situ from the air-stable precursors: the nickel chloride complex with pyridine (NiCl2Py2), imidazolium salt IMes•HCl (IMes is 1,3-bis(2,4,6-trimethylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene) as the carbene source, and sodium tert-butoxide (ButONa). The advantages of the developed approach are availability of the components of the catalytic system, no necessity to apply special agents for the reduction of NiII to Ni0, and simplification of the synthesis procedure. [ABSTRACT FROM AUTHOR]

Zwitterionic compounds are an emergent class of energetic materials and have gained synthetic interest of many in the recent years. Due to their better packing efficiencies and strong inter/intramolecular electrostatic interactions, they often ensue superior energetic properties than their salt analogues. A systematic review from the perspective of design, synthesis, and physicochemical properties evaluation of the zwitterionic energetic materials is presented. Depending on the parent ring(s) used for the synthesis and the type of moieties bearing positive and negative charges, different classes of energetic materials, such as primary explosives, secondary explosives, heat resistant explosives, oxidizers, etc., may result. The properties of some of the energetic zwitterionic compounds are also compared with analogous energetic salts. This review will encourage readers to explore the possibility of designing new zwitterionic energetic materials. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Faculty of Pharmacy of Ankara University / Ankara Üniversitesi Eczacilik Fakültesi Dergisi is the property of Ankara University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Invasive fungal infections are rapidly increasing, and the opportunistic pathogenic Candida species are the fourth most common cause of nosocomial systemic infections. The current antifungal classes, of which azoles are the most widely used, all have shortcomings. Azoles are generally considered fungistatic rather than fungicidal, they do not actively kill fungal cells and therefore resistance against azoles can be rapidly acquired. Combination therapies with azoles provide an interesting therapeutic outlook and agents limiting iron are excellent candidates. We summarize how iron is acquired by the host and transported towards both storage and iron‐utilizing organelles. We indicate whether these pathways alter azole susceptibility and/or tolerance, to finally link these transport mechanisms to mitochondrial iron availability. In this review, we highlight putative novel intracellular iron shuffling mechanisms and indicate that mitochondrial iron dynamics in relation to azole treatment and iron limitation is a significant knowledge gap. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusion Nakaseomyces glabratus (N. glabratus) formerly known as Candida glabrata (C. glabrata), is an endogenous opportunistic pathogen, which is generally located in the gastrointestinal tract but can spread in immunocompromised patients. N. glabratus is the second most common pathogen that causes candidemia in several countries. N. glabratus virulence factors may increase antifungal resistance and reduce the number of available treatment options. High resistance to azoles and increasing resistance to echinocandins have been previously reported in N. glabratus.To establish the distribution of N. glabratus isolates in Europe and its drug susceptibility/resistance in each country over the last 7 years.The search was performed across three databases: PubMed, Scopus and Scielo, using the MeSH terms: “Candida glabrata”, “Nakaseomyces glabratus”, “Europe”, “resistance” and “Epidemiology” exclusively in English. All available information from January 2002 to December 2022 was included, excluding reviews, meta‐analyses and book chapters.Fifty‐seven articles with information on antifungal susceptibility in Europe were retrieved and analysed with a total of 15,400 reported C. glabrata isolates. Remarkably, nations that presented the maximum number of cases during the study period included the United Kingdom (n = 7241, 47.02%), France (n = 3190, 20.71%), Spain (n = 900, 5.84%), Hungary (n = 745, 4.84%) and Italy (n = 486, 3.16%). C. glabrata isolates presented resistance to azoles [voriconazole (n = 2225, 14.45%), fluconazole (n = 1612, 10.47%), itraconazole (n = 337, 2.19%) and clotrimazole (n = 89, 0.58%)], increased resistance to echinocandins, especially to anidulafungin (n = 138, 0.89%), and high sensitivity to amphotericin B.The number of candidemia cases associated with triazole‐resistant N. glabratus isolates have been increasing in Europe. Therefore, echinocandins and amphotericin B can be considered optional empirical treatments; however, antifungal susceptibility testing is required to determine the best therapeutic options. [ABSTRACT FROM AUTHOR]

The reactivity of imidazole, pyrazole, 1,2,4‐triazole, 1,2,3‐triazole, and tetrazole with acetone (propan‐2‐one) has been studied by 1H and 13C NMR using acetone‐d6 as solvent at temperatures ranging from 173 to 300 K at 10 K intervals. Simultaneously, the reaction has been theoretically calculated at the B3LYP/6‐311++G(d,p) level, and experimental and theoretical results have been compared. The equilibrium constants between azoles and adducts α,α‐dimethyl‐azole‐methanol were analyzed, assuming that the straight part of the plots –R ln Ke vs. 1/T can be used to determine ΔH and ΔS. Calculated and experimental data are related, but the theoretical values are proportionally higher. The tautomerism of triazoles and tetrazole has been considered in order to discuss the reactions. [ABSTRACT FROM AUTHOR]

Plenodomus lingam (Leptosphaeria maculans) and P. biglobosus (L. biglobosa) are fungi causing Phoma leaf spot/stem canker, an international damaging disease of oilseed rape (Brassica napus) and other brassicas. In Europe, fungicides used for disease management are mainly sterol 14α‐demethylase (CYP51) inhibitors (DMIs/azoles); quinone‐outside inhibitors (QoIs) and succinate dehydrogenase inhibitors (SDHIs) are also used. Decreased DMI sensitivity has emerged in Australian and eastern European P. lingam populations and is mediated by CYP51 promoter inserts resulting in target site overexpression. In this study using in vitro sensitivity testing, we report decreased DMI (prothioconazole‐desthio, mefentrifluconazole) sensitivity in modern western European P. lingam isolates (collected 2022–2023) compared to older baseline (1992–2005) isolates. Around 85% of modern western European P. lingam isolates collected, for which the CYP51 promoter region was sequenced, carried a promoter insert, but target site alterations were not detected. Six different CYP51 promoter inserts were identified, most commonly a 237 bp fragment of the Sahana transposable element. Inserts were associated with an approximately 3‐ to 10‐fold decrease in sensitivity to the DMIs tested. In contrast to P. lingam, PCR screening revealed CYP51 promoter inserts were absent in modern western European P. biglobosus isolates (2021–2023). Combined data indicate P. lingam isolates lacking an insert were similarly (or slightly more) sensitive to the DMIs tested for P. biglobosus, whereas those carrying an insert were slightly less sensitive than P. biglobosus. No evidence for substantive sensitivity shifts to the QoI (pyraclostrobin) or SDHI (boscalid) fungicides tested was obtained for either Plenodomus species. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance poses a major threat to global health as the number of efficient antimicrobials decreases and the number of resistant pathogens rises. Our research group has been actively involved in the design of novel antimicrobial drugs. The blueprints of these compounds were azolic heterocycles, particularly thiazole. Starting with oxadiazolines, our research group explored, one by one, the other five-membered heterocycles, developing more or less potent compounds. An overview of this research activity conducted by our research group allowed us to observe an evolution in the methodology used (from inhibition zone diameters to minimal inhibitory concentrations and antibiofilm potential determination) correlated with the design of azole compounds based on results obtained from molecular modeling. The purpose of this review is to present the development of in-house azole compounds with antimicrobial activity, designed over the years by this research group from the departments of Pharmaceutical and Therapeutical Chemistry in Cluj-Napoca. [ABSTRACT FROM AUTHOR]

Fungal resistance is a public health concern due to the limited availability of antifungal resources and the complexities associated with treating persistent fungal infections. Azoles are thus far the primary line of defense against fungi. Specifically, azoles inhibit the conversion of lanosterol to ergosterol, producing defective sterols and impairing fluidity in fungal plasmatic membranes. Studies on azole resistance have emphasized specific point mutations in CYP51/ERG11 proteins linked to resistance. Although very insightful, the traditional approach to studying azole resistance is time-consuming and prone to errors during meticulous alignment evaluation. It relies on a reference-based method using a specific protein sequence obtained from a wild-type (WT) phenotype. Therefore, this study introduces a machine learning (ML)-based approach utilizing molecular descriptors representing the physiochemical attributes of CYP51/ERG11 protein isoforms. This approach aims to unravel hidden patterns associated with azole resistance. The results highlight that descriptors related to amino acid composition and their combination of hydrophobicity and hydrophilicity effectively explain the slight differences between the resistant non-wild-type (NWT) and WT (nonresistant) protein sequences. This study underscores the potential of ML to unravel nuanced patterns in CYP51/ERG11 sequences, providing valuable molecular signatures that could inform future endeavors in drug development and computational screening of resistant and nonresistant fungal lineages. [ABSTRACT FROM AUTHOR]

Candida parapsilosis is one of the most commen causes of life-threatening candidaemia, particularly in premature neonates, individuals with cancer of the haematopoietic system, and recipients of organ transplants. Historically, drug-susceptible strains have been linked to clonal outbreaks. However, worldwide studies started since 2018 have reported severe outbreaks among adults caused by fluconazole-resistant strains. Outbreaks caused by fluconazole-resistant strains are associated with high mortality rates and can persist despite strict infection control strategies. The emergence of resistance threatens the efficacy of azoles, which is the most widely used class of antifungals and the only available oral treatment option for candidaemia. The fact that most patients infected with fluconazole-resistant strains are azole-naive underscores the high potential adaptability of fluconazole-resistant strains to diverse hosts, environmental niches, and reservoirs. Another concern is the multidrug-resistant and echinocandin-tolerant C parapsilosis isolates, which emerged in 2020. Raising awareness, establishing effective clinical interventions, and understanding the biology and pathogenesis of fluconazole-resistant C parapsilosis are urgently needed to improve treatment strategies and outcomes.

From the standpoint of chemical structures, the organic backbones of energetic materials can be classified into aromatic rings, nonaromatic rings, and open chains. Although the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties, the nonaromatic heterocycles, assembling nitramino explosophores with simple alkyl bridges, still have prevailed in benchmark materials. The methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds, e.g., hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20). In this context, it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles, thereby expanding the structural diversity of energetic materials, e.g., bridged and fused nitrogen-rich poly-heterocycles. Furthermore, alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic materials. In this review, the development of alkyl bridges in linking nitrogen-rich heterocycles is presented, and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials.

Introduction. Vulvovaginal candidiasis is an extremely common pathology of the female genital organs, leading to a long-term recurrent course and multiple complications. Although currently it is widely known about developing antibiotic resistance of bacterial pathogens, it is necessary to remember about similar phenomenon observed in other groups of infectious agents. In this regard, fungal infection also requires development of new therapeutic techniques and medicinal antifungal drugs, such as ibrexafungerp. Aim: to analyze available publications revealing the mechanism of action, efficacy, antifungal spectrum and results of clinical trials for a new oral antifungal drug ibrexafungerp. Materials and Methods. A search for publications in the electronic databases PubMed, eLibrary and ClinicalTrials.gov, published over the last 25 years was conducted using the following keywords in Russian and English: “candidiasis”, “vulvovaginal candidiasis”, “antifungal drugs”, “ibrexafungerp”, “clinical trials”, “mechanism of action”. Articles were assessed according to PRISMA guidelines. The titles and abstracts of identified publications were independently reviewed to retrieve relevant full text studies. After the selection procedure, 46 articles were included in the review. Results. This review provides information on the creation of the drug ibrexafungerp, its mechanism of action, the activity against a relatively wide range of pathogens, as well as the results from 13 ongoing and completed clinical trials in patients with fungal infection. Conclusion. The analysis of ibrexafungerp-related clinical studies showed its good oral bioavailability, high antifungal efficacy, so that its one-day dosage may further eliminate a need for unnecessarily long hospitalization and complex dosing schedules, thereby increasing adherence to therapy and odds for treatment success.

Azole fungicides are used for spraying crops and also in seed treatments of corn, wheat and other important agricultural crops, in which seeds are dressed with a plastic-like coat containing an azole fungicide and other seed and seedling protection agents. In this study, the effect of tebuconazole in corn seed treatment on selecting for tebuconazole-resistant A. flavus isolates was investigated. Seed-borne A. flavus isolates growing during seed germination were tested for tebuconazole resistance. When seeds were treated with increasing dosages of tebuconazole, the relative abundance of resistant isolates increased. At the recommended dosage, up to 72.1 % of the seed borne A. flavus isolates that emerged from germinating seeds were resistant to tebuconazole. Resistance increased to 83.4 and 95.1 %, when dosages were doubled or quadrupled, respectively. Application of tebuconazole also increased the abundance of aflatoxin-producing isolates of A. flavus, from 32.2 % in untreated seeds to 67.4 % in seeds receiving the highest dosage. Results from this study suggest that seed treatment with tebuconazole should be included in the list of hotspots that induce resistance to azole antifungals and that measures and strategies, such as alternative fungicides with different metabolic targets, should be considered for reducing this risk.

Azole antifungals inhibit the sterol C14-demethylase (CYP51/Erg11) of the ergosterol biosynthesis pathway. Here we show that the azole-induced synthesis of fungicidal cell wall carbohydrate patches in the pathogenic mold Aspergillus fumigatus strictly correlates with the accumulation of the CYP51 substrate eburicol. A lack of other essential ergosterol biosynthesis enzymes, such as sterol C24-methyltransferase (Erg6A), squalene synthase (Erg9) or squalene epoxidase (Erg1) does not trigger comparable cell wall alterations. Partial repression of Erg6A, which converts lanosterol into eburicol, increases azole resistance. The sterol C5-desaturase (ERG3)-dependent conversion of eburicol into 14-methylergosta-8,24(28)-dien-3β,6α-diol, the "toxic diol" responsible for the fungistatic activity against yeasts, is not required for the fungicidal effects in A. fumigatus. While ERG3-lacking yeasts are azole resistant, ERG3-lacking A. fumigatus becomes more susceptible. Mutants lacking mitochondrial complex III functionality, which are much less effectively killed, but strongly inhibited in growth by azoles, convert eburicol more efficiently into the supposedly "toxic diol". We propose that the mode of action of azoles against A. fumigatus relies on accumulation of eburicol which exerts fungicidal effects by triggering cell wall carbohydrate patch formation. Azole antifungals inhibit the ergosterol biosynthesis enzyme CYP51, but their effects on fungal viability and growth vary greatly among fungal species. Here, the authors provide evidence that the mode of action of azoles against Aspergillus fumigatus relies on accumulation of the CYP51 substrate eburicol, which exerts fungicidal effects by triggering cell-wall carbohydrate patch formation. [ABSTRACT FROM AUTHOR]

N,N‐dialkylbenzofuran‐ and N,N‐dialkylbenzothiophene‐2‐carboxamides were readily prepared from bare benzofuran and benzothiophene by deprotocupration followed by trapping with N,N‐dialkylcarbamoyl chlorides. They were reacted with 2‐benzofuryl‐ and 2‐benzothienyllithiums to form symmetrical and unsymmetrical diarylketones, or underwent deprotolithiation‐electrophilic trapping sequences at their 3 position. From 3‐iodinated derivatives, copper‐catalysed N‐arylation of azoles was performed, followed by lithium amide‐promoted cyclisation, to give 'tripentone' analogues. The diarylketones were also iodinated at their 3,3' positions and then engaged in the copper‐promoted double N‐arylation of anilines, giving rise to a family of original pentacyclic derivatives. A preliminary assessment of their electrochemical and biological properties was carried out, showing promising results against the proliferation of melanoma cells. [ABSTRACT FROM AUTHOR]

Background: The resistance of Aspergillus flavus to the azole antifungal drugs is an emerging problem. Mutations in the molecular targets of the azole antifungals ‐ CYP 51 A, B and C ‐ are possible mechanisms of resistance, but data to confirm this hypothesis are scarce. In addition, the behaviour of resistant strains in vitro and in vivo is not yet understood. Objectives: This study had 3 objectives. The first was to compare the sequences of CYP51 A, B and C in resistant and susceptible strains of A. flavus. The second was to look for the existence of a fitness cost associated with resistance. The third was to evaluate the activity of voriconazole and posaconazole on resistant strains in the Galleria mellonella model. Methods: The CYP51 A, B and C sequences of seven resistant strains with those of four susceptible strains are compared. Fitness costs were assessed by growing the strains in RPMI medium and testing their virulence in G. mellonella larvae. In addition, G. mellonella larvae infected with strains of A. flavus were treated with voriconazole and posaconazole. Results: In the CYP51A sequences, we found the A91T, C708T and A1296T nucleotide substitutions only in the resistant strains. The resistant strains showed a fitness cost with reduced in vitro growth and reduced virulence in G. mellonella. In vivo resistance to posaconazole is confirmed in a strain with the highest MIC for this antifungal agent. Conclusions: These results allow to conclude that some substitutions in CYP51 genes, in particular CYP51A, contribute to resistance to azole drugs in A. flavus. The study of the relationship between drug dosage and treatment duration with resistance and the reduction of fitness costs in resistant strains is a major perspective of this study. This work could help to establish recommendations for the treatment of infections with resistant strains of A. flavus. [ABSTRACT FROM AUTHOR]

Background: Candida vulturna is an emerging pathogen belonging to the Metshnikowiaceae family together with Candida auris and Candida haemulonii species complex. Some strains of this species were reported to be resistant to several antifungal agents. Objectives: This study aims to address identification difficulties, evaluate antiungal susceptibilities and explore the molecular mechanisms of azole resistance of Candida vulturna. Methods: We studied five C. vulturna clinical strains isolated in three Colombian cities. Identification was performed by phenotypical, proteomic and molecular methods. Antifungal susceptibility testing was performed following CLSI protocol. Its ERG11 genes were sequenced and a substitution was encountered in azole resistant isolates. To confirm the role of this substitution in the resistance phenotype, Saccharomyces cerevisiae strains with a chimeric ERG11 gene were created. Results: Discrepancies in identification methods are highlighted. Sequencing confirmed the identification as C. vulturna. Antifungal susceptibility varied among strains, with four strains exhibiting reduced susceptibility to azoles and amphotericin B. ERG11 sequencing showed a point mutation (producing a P135S substitution) that was associated with the azole‐resistant phenotype. Conclusions: This study contributes to the understanding of C. vulturna's identification challenges, its susceptibility patterns, and sheds light on its molecular mechanisms of azole resistance. [ABSTRACT FROM AUTHOR]

The medicinal chemistry of ferrocene has gained its momentum after the discovery of biological activities of ferrocifen and ferroquine. These ferrocenyl drugs have been designed by replacing the aromatic moiety of the organic drugs, tamoxifen and chloroquine respectively, with a ferrocenyl unit. The promising biological activities of these ferrocenyl drugs have paved a path to explore the medicinal applications of several ferrocenyl conjugates. In these conjugates, the ferrocenyl moiety has played a vital role in enhancing or imparting the anticancer activity to the molecule. The ferrocenyl conjugates induce the cytotoxicity by generating reactive oxygen species and thereby damaging the DNA. In medicinal chemistry, the five membered nitrogen heterocycles (azoles) play a significant role due to their rigid ring structure and hydrogen bonding ability with the biomolecules. Several potent drug candidates with azole groups have been in use as chemotherapeutics. Considering the importance of ferrocenyl moiety and azole groups, several ferrocenyl azole conjugates have been synthesized and screened for their biological activities. Hence, in the view of a wide scope in the development of potent drugs based on ferrocenyl azole conjugates, herein we present the details of synthesis and the anticancer activities of ferrocenyl compounds bearing azole groups such as imidazole, triazoles, thiazole and isoxazoles. [ABSTRACT FROM AUTHOR]

Based on cations of diazo group, imino group and nitrogen-rich azole, the synthetic strategies and properties of az-ole, bis-azoles and fused heterocycle-based zwitterionic energetic materials were reviewed in recent ten years, and the influence of molecular structures on their energetic performance and stability was clarified. Meanwhile, the future directions on the zwitterionic energetic materials based on nitrogen-rich azoles were pointed out: (1) Diazonium zwitterionic energetic materials outperform DDNP in detonation performance, warranting deeper research into heat-resistant explosives, harnessing alkyl-bridged, fused-ring nitrogen-rich azoles. (2) The imino-gem-dinitromethyl zwitterionic energetic materials can alleviate the sensitivity of diazonium salts, but their thermal stability still requires further optimization. (3) The modifiable structure of nitrogen-rich azole cation energetic salts and explosive groups, and synergies with ionic salts, cocrystals should be fully explored, which could effectively expand their applications in high-energy insensitive explosives, high-energy propellants, green gas generators, and heat-resistant energetic materials. [ABSTRACT FROM AUTHOR]

In the realm of energetic materials research, there has been notable interest in energetic coordination compounds (ECCs) owing to their remarkable thermal stability and resistance to mechanical stimuli. This study successfully demonstrated the synthesis of an azole-based C–C bonded ECC1 under ambient conditions. A comprehensive characterization study, employing techniques such as IR, TGA-DSC, NMR and single-crystal X-ray diffraction analysis, was conducted. The bulk compound was investigated by PXRD analysis. In-depth exploration of its physicochemical and energetic performance revealed good detonation properties such as a detonation velocity (VOD) of 8553 m s−1 and a detonation pressure (DP) of 36.2 GPa, which surpass those of heat resistant explosives HNS and TATB. Due to its remarkable high melting and onset decomposition temperature (278/379 °C), it also outperforms the benchmark explosive HMX (279 °C) and the heat-resistant explosive HNS (318 °C) and shows a high impact sensitivity (IS) of 20 J and friction sensitivity (FS) of 360 N. The study also employed Hirshfeld surface and 2D fingerprint analysis to elucidate the close contact of atoms within the molecules. The combination of high detonation properties, thermal stability, and low sensitivity makes the synthesized ECC1 intriguing for further investigations and suggests its potential applications as a safe and high-energy-dense material. [ABSTRACT FROM AUTHOR]

Treatment of 2-methylsulfinylbenzazoles with triflic anhydride in the presence of phenols yields the corresponding 4-(p-hydroxyphenyl)-2-methylsulfanylbenzazoles. This regioselective dehydrative C–H/C–H coupling arylation represents a rare example of functionalizations on the benzene rings of benzo-fused azoles. [ABSTRACT FROM AUTHOR]

Introduction: Fungal diseases are frequently associated with elevated mortality rates in elasmobranchs. Currently, there is a notable absence of scientifically validated therapeutic medications that can ensure both effectiveness and safety when administered to this group of animals. The empirical prescription of azole antifungal agents, particularly voriconazole, has been posited as a potentially efficacious treatment approach for addressing most common mycoses in sharks and rays. However, there are still no published pharmacokinetic studies supporting its use in elasmobranchs and there is a lack of scientific base for its utilization in elasmobranchs. Methods: For this study, voriconazole was administered intravenously (IV) and intramuscularly (IM), at a single dose of 4 mg/kg to six adult undulate skates (Raja undulata). A washout period of 8 weeks was left between each route of administration. Blood samples were collected both before and at ten predetermined intervals after each dosing (0.25, 0.5, 1, 1.5, 2, 4, 8, 12, 24, and 36 h after drug administration). Plasma concentrations were quantified using a validated high-performance liquid chromatography method, and pharmacokinetic (PK) data was analyzed through non-compartmental methods. Results: The mean extrapolated concentration at 0 h (C0) after IV administration was 27.19 ± 7.15 µg/mL and the mean peak plasma concentrations (Cmax) ± SEM after IM administration resulted 2.98 ± 0.28 µg/mL at a mean time to maximum concentration (T max) of 1.33 ± 0.17 h. Terminal half-lives were calculated and resulted 11.18 ± 1.32 h for IV injections and 9.59 ± 1.38 h for IM injections. The area under the curve extrapolated to infinity was determined as 58.14 ± 2.79 h·µg/ml following IV injections and 37.60 ± 6.67 h·µg/ml following IM injections. The IM-administered voriconazole exhibited a mean absolute bioavailability of 64.67 ± 11.47%. Discussion: These discoveries provide backing for the possible application of voriconazole through the intramuscular route in undulate skates and support using lower dosage regimens compared to those required for oral administration, emphasizing the importance of conducting further pharmacokinetic studies with antifungals in elasmobranchs. [ABSTRACT FROM AUTHOR]