Sertaconazole, an Imidazole Antifungal Agent, Suppresses the Stemness of Breast Cancer Cells by Inhibiting Stat3 Signaling

BACKGROUND/AIM

Breast cancer stem cells (BCSCs) are a subpopulation of tumor cells that play a role in therapeutic resistance. In this study, we demonstrated that sertaconazole, an antifungal agent, displayed a potent inhibition on cancer stem cells (CSCs) and investigated the mechanism of action involved in its anti-BCSC effect.

MATERIALS AND METHODS

The effect of sertaconazole on BCSCs was investigated using a mammosphere formation assay, a colony formation assay, and a cell migration assay. In addition, CD44high/CD24low and ALDEFLOR analyses, an apoptosis assay, quantitative real-time PCR, western blotting, an electrophoretic mobility shift assay, and a cytokine profiling assay were performed.

RESULTS

Sertaconazole inhibited cell proliferation, colony formation, cell migration, mammosphere formation, and mammosphere proliferation. It also induced apoptosis of breast cancer cells. It decreased the subpopulation of CD44high/CD24low and aldehyde dehydrogenase-expressing cells. It also reduced the DNA binding of Stat3 and nuclear protein expression levels of phosphorylated Stat3. Furthermore, it reduced the IL-8 mRNA levels of the mammosphere.

CONCLUSION

Sertaconazole can inhibit the Stat3 and IL-8 signaling pathways and induce CSC death. Thus, sertaconazole might be a potential inhibitor of BCSCs.

Medicinal chemistry-based perspectives on thiophene and its derivatives: exploring structural insights to discover plausible druggable leads

Thiophene is a privileged pharmacophore in medicinal chemistry owing to its diversified biological attributes. The thiophene moiety has been ranked 4th in the US FDA drug approval of small drug molecules, with around 7 drug approvals over the last decade. The present review covers USFDA-approved drugs possessing a thiophene ring system. Our analysis reveals that 26 drugs possessing thiophene nuclei have been approved under different pharmacological classes. The review further covers reported thiophene and its substituted analogues with diverse biological activities, including anti-diabetic, anticancer, anti-inflammatory, anticonvulsant, and antioxidant activity. Besides, a section is dedicated to appreciating the implications of structural bioinformatics in drug discovery. Additionally, the manuscript delves into structure-activity relationship studies to explore the chemical groups responsible for eliciting potential therapeutic activities. The review may provide invaluable insights for researchers working with thiophene nuclei in developing novel analogues with greater efficacy and fewer side effects.

Sertaconazole 300 mg versus clotrimazole 500 mg vaginal suppository for treating pregnant women with acute vaginal candidiasis: a double-blinded, randomized trial

BACKGROUND

Vaginal candidiasis (VC) commonly affects pregnant women. Traditionally, clotrimazole vaginal tablets (CLO) have been the cornerstone of management. However, sertaconazole ovules (SER) offer a novel topical antimycotic option. This double-blinded, randomized trial evaluated the efficacy of single-dose SER and CLO in treating acute VC during pregnancy.

METHODS

From June 2020 to May 2021, this trial recruited pregnant women aged ≥ 18 years with VC symptoms (abnormal vaginal discharge and/or vulvar/vaginal itching) confirmed by microscopy. Participants with ≥ 4 VC episodes in the prior year, immunocompromised status, or imidazole contraindications and those who were absent at the 2-week follow-up were excluded. Participants were randomized to receive either 300 mg SER or 500 mg CLO. Evaluations 2 weeks after the initial medication administration included clinical cure (self-reported resolution of all symptoms), microscopic cure (pseudohyphal absence), patient satisfaction, side effects, and time to clinical cure. Participants with persistent VC received weekly SER doses until delivery. Assessments of recurrence and pregnancy outcomes were done.

RESULTS

The analysis included 96 participants (48 per group, mean age 27.4 ± 7.4 years, gestational age at diagnosis 22.9 ± 6.4 weeks). Without statistical significance, SER achieved a higher clinical cure rate (62.5% vs 50%, p = 0.217; a mean difference of 12.5%, 95%CI: -17.5% to 42.5%; and a rate ratio of 1.25, 95%CI: 0.71 to 2.23) and a lower microscopic cure (47.9% vs. 62.5%, p = 0.151; a mean difference of -14.6%, 95%CI: -44.3% to 15.1%; and a rate ratio of 0.77, 95%CI: 0.43 to 1.37). The two groups had comparable times to clinical cure (SER: 3.1 ± 1.8 days, CLO: 3.4 ± 2.7 days; p = 0.848) and substantial satisfaction rates (SER: 66.7%, CLO: 60.4%; p = 0.753). No side effects were reported. Of 60 participants who gave birth at Siriraj Hospital, there were no significant differences in pregnancy outcomes. Repeated SER dosing eradicated symptoms and enhanced the microscopic cure rate. Recurrence was observed in four SER and two CLO participants within 1-2 months.

CONCLUSION

In the treatment of acute VC during pregnancy, 300 mg SER and 500 mg CLO exhibited comparable efficacy in terms of clinical and microscopic cure rates, satisfaction, side effects, time to clinical cure, recurrence rates, and pregnancy outcomes.

TRIAL REGISTRATION

TCTR20190308004 (registration date March 8, 2019).

Integrative Approaches to Sleep Management in Skin Disease: Systematic Review

BACKGROUND

Dermatological conditions, especially when severe, can lead to sleep disturbances that affect a patient's quality of life. However, limited research exists on the efficacy of treatments for improving sleep parameters in skin conditions.

OBJECTIVE

The objective was to perform a systematic review of the literature on dermatological conditions and the treatments available for improving sleep parameters.

METHODS

A literature review was performed using the PubMed, Ovid MEDLINE, Embase, Cochrane, and ClinicalTrials.gov databases from 1945 to 2021. After filtering based on our exclusion criteria, studies were graded using the SORT (Strength of Recommendation Taxonomy) algorithm, and only those receiving a grade of "2" or better were included.

RESULTS

In total, 25 treatment studies (n=11,025) assessing sleep parameters related to dermatological conditions were found. Dupilumab appeared to be the best-supported and most effective treatment for improving sleep in atopic dermatitis (AD) but had frequent adverse effects. Topical treatments for AD were mostly ineffective, but procedural treatments showed some promise. Treatments for other conditions appeared efficacious.

CONCLUSIONS

The evaluation of sleep parameter changes in dermatological treatments is predominantly restricted to AD. Systemic interventions such as dupilumab and procedural interventions were the most efficacious. Sleep changes in other dermatoses were limited by a paucity of available studies. The inclusion of a sleep assessment component to a broader range of dermatological treatment studies is warranted.

Visible-light-induced halocyclization of 2-alkynylthioanisoles with simple alkyl halides towards 3-halobenzo[b]thiophenes without an external photocatalyst

A new strategy for the preparation of 3-halobenzo[b]thiophenes via a photo-driven halocyclization/demethylation of 2-alkynylthioanisoles with simple alkyl halides was developed. The reaction can proceed smoothly at room temperature under visible-light irradiation without any external photocatalyst, and the protocol has a range of advantages, including simplicity and mildness of the reaction conditions, good functional-group tolerance, and excellent yields of the products.

Membranolytic Activity Profile of Nonyl 3,4-Dihydroxybenzoate: A New Anti-Biofilm Compound for the Treatment of Dermatophytosis

The ability of dermatophytes to live in communities and resist antifungal drugs may explain treatment recurrence, especially in onychomycosis. Therefore, new molecules with reduced toxicity that target dermatophyte biofilms should be investigated. This study evaluated nonyl 3,4-dihydroxybenzoate (nonyl) susceptibility and mechanism of action on planktonic cells and biofilms of T. rubrum and T. mentagrophytes. Metabolic activities, ergosterol, and reactive oxygen species (ROS) were quantified, and the expression of genes encoding ergosterol was determined by real-time PCR. The effects on the biofilm structure were visualized using confocal electron microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). T. rubrum and T. mentagrophytes biofilms were susceptible to nonyl and resistant to fluconazole, griseofulvin (all strains), and terbinafine (two strains). The SEM results revealed that nonyl groups seriously damaged the biofilms, whereas synthetic drugs caused little or no damage and, in some cases, stimulated the development of resistance structures. Confocal microscopy showed a drastic reduction in biofilm thickness, and transmission electron microscopy results indicated that the compound promoted the derangement and formation of pores in the plasma membrane. Biochemical and molecular assays indicated that fungal membrane ergosterol is a nonyl target. These findings show that nonyl 3,4-dihydroxybenzoate is a promising antifungal compound.

A Meta-Analysis on the Effectiveness of Sertaconazole 2% Cream Compared with Other Topical Therapies for Seborrheic Dermatitis

Seborrheic dermatitis (SD) is a relapsing inflammatory skin disorder that affects the seborrheic areas of the body. Its etiology is not completely elucidated; however, the link between disease exacerbations and the proliferation of Malassezia spp., along with the good response to antifungal agents, indicate the role of fungi in its pathophysiology. Sertaconazole nitrate is a relatively new imidazole antifungal agent with a particular structure, consisting in a benzothiophene ring similar to the indole ring of tryptophan, and it acts mainly through the inhibition of ergosterol synthesis and the formation of pores in the fungal cell membrane. The aim of our study was to evaluate the efficiency of sertaconazole 2% cream compared with other topical treatments in patients with SD. We performed an extensive literature search by browsing the PubMed database with the keyword combination “sertaconazole AND seborrheic dermatitis AND clinical trial”, which retrieved eight controlled clinical trials evaluating the effects of sertaconazole in SD. All of the clinical trials included a standard scoring index (SI). At 28 days since the beginning of the treatment, the sertaconazole regimen was associated with a significantly higher percentage of patients with mild SI and a lower percentage of patients with moderate or severe SI (odds ratio 0.51) than the other investigated treatments—hydrocortisone, ketoconazole, clotrimazole, metronidazole, pimecrolimus, and tacrolimus (odds ratio 1.95). In conclusion, treatment with sertaconazole 2% cream may represent an efficient alternative therapy for patients with SD.

Hydroxyl containing benzo[b]thiophene analogs mitigates the acrylamide induced oxidative stress in the zebrafish larvae by stabilizing the glutathione redox cycle

AIMS

This study aims to elucidate a systematic free-radical quenching ability of synthesized benzo[b]thiophene derivatives using in vitro assays and acrylamide induced oxidatively stressed model in zebrafish larvae.

MATERIALS AND METHODS

Antioxidant activity of the compounds was evaluated using in vitro methods. The toxicity of the compounds was evaluated in Madin-Darby Canine Kidney (MDCK) cell line and zebrafish embryos. Oxidative stress was generated by acrylamide (1 mM) in zebrafish larvae and treated with compounds to evaluate the in vivo antioxidant ability. Specific fluorescence dyes were used to detect ROS generation, lipid peroxidation, and cell death followed by gene expression using RT PCR. Density functional theory (DFT) and in silico pharmacokinetics were also studied.

KEY FINDINGS

Compound BP and EP have a greater in vitro free radical scavenging ability. The maximum tolerated concentration (MTC) of the compounds in zebrafish larvae is 80 μM. The antioxidant system in zebrafish larvae was dysregulated due to acrylamide exposure and improvement was found while treating acrylamide exposed larvae with compounds 1-(3-hydroxybenzo[b]thiophen-2-yl) ethanone (BP) and 1-(3-hydroxybenzo[b]thiophen-2-yl) propan-1-one hydrate (EP). Compound BP and EP enhanced the SOD and CAT activity, reduced the ROS and lipid peroxidation level, thus decreasing cell death in zebrafish larvae. Compound BP and EP also improved the glutathione redox cycle by stabilizing glutathione-related gene expressions.

SIGNIFICANCE

Hydroxyl-containing compounds BP and EP are promising lead molecules for pathological conditions related to oxidative stress, which showed an attenuated effect on acrylamide-induced oxidative stress in zebrafish larvae by enhancing the glutathione redox cycle and enzymatic antioxidants.

UVA Light-promoted Catalyst-free Cyclization of Vinyl Selenides: Green and Efficient Synthesis of C3-Unsubstituted 2-Selanyl Benzochalcogenophenes

A metal- and catalyst-free photo-promoted cyclization of properly substituted vinyl selenides was developed using UVA irradiation. A total of eighteen new C3-unsubstituted 2-selanyl benzochalcogenophenes (benzofurans, benzothiophenes and benzoselenophenes) were prepared in 30-86% yield after irradiation with UVA at room temperature. The usefulness of the title compounds was demonstrated in the easy functionalization of the remaining free C-H bond of the benzochalcogenophenes to form new C-Se and C-Br bonds by simple procedures. Furthermore, the reaction can be performed under natural sunlight irradiation and the solvent is easily reused further in several subsequent runs.

Efficacy of antifungal agents against fungal spores: An in vitro study using microplate laser nephelometry and an artificially infected 3D skin model

Dermal fungal infections seem to have increased over recent years. There is further a shift from anthropophilic dermatophytes to a growing prevalence of zoophilic species and the emergence of resistant strains. New antifungals are needed to combat these fungi and their resting spores. This study aimed to investigate the sporicidal effects of sertaconazole nitrate using microplate laser nephelometry against the microconidia of Trichophyton, chlamydospores of Epidermophyton, blastospores of Candida, and conidia of the mold Scopulariopsis brevicaulis. The results obtained were compared with those from ciclopirox olamine and terbinafine. The sporicidal activity was further determined using infected three-dimensional full skin models to determine the antifungal effects in the presence of human cells. Sertaconazole nitrate inhibited the growth of dermatophytes, molds, and yeasts. Ciclopirox olamine also had good antifungal activity, although higher concentrations were needed compared to sertaconazole nitrate. Terbinafine was highly effective against most dermatophytes, but higher concentrations were required to kill the resistant strain Trichophyton indotineae. Sertaconazole nitrate, ciclopirox olamine, and terbinafine had no negative effects on full skin models. Sertaconazole nitrate reduced the growth of fungal and yeast spores over 72 h. Ciclopirox olamine and terbinafine also inhibited the growth of dermatophytes and molds but had significantly lower effects on the yeast. Sertaconazole nitrate might have advantages over the commonly used antifungals ciclopirox olamine and terbinafine in combating resting spores, which persist in the tissues, and thus in the therapy of recurring dermatomycoses.

The Efficacy and Safety of Pimecrolimus 1% Cream versus Sertaconazole 2% Cream in the Treatment of Patients with Facial Seborrheic Dermatitis: A Randomized Blinded Trial

BACKGROUND

Facial seborrheic dermatitis (FSD) as a chronic inflammatory skin disorder is characterized by remission and exacerbation episodes. In most cases, FSD requires a long-term treatment.

OBJECTIVES

This study aimed to compare the efficacy and safety of pimecrolimus and sertaconazole in patients with FSD.

METHODS

In this double-blinded, and randomized trial 60 patients with FSD were included and instructed to topically apply either pimecrolimus 1% cream (30 patients) or sertaconazole 2% cream (30 patients) twice daily for 4-weeks. Assessment of the disease severity was performed at baseline, on day 14 and day 28, and 4 weeks after termination of treatment, based on Scoring Index (SI). The levels of satisfaction from treatment and side effects were also assessed in both groups.

RESULTS

Although the severity of disease reduced upon treatment in both groups, application of pimecrolimus caused a significant improvement as compared to the sertaconazole on day 14 and day 28 (P=0.002 and P<0.001, respectively). The rate of relapse was significantly lower in the pimecrolimus group as compared to the sertaconazole after 28 days of treatment termination (P=0.012). The highest level of satisfaction (46.7%) was observed on day 28 in pimecrolimus group. Both of topical treatments had acceptable safety profiles, however, pimecrolimus 1% cream showed more safety compared to the sertaconazole 2% cream, in the term of irritation (P=0.003).

CONCLUSION

This study showed that pimecrolimus was associated with a quicker response and fewer side effects as compared to sertaconazole in patients with FSD.

Sertaconazole provokes proapoptotic autophagy via stabilizing TRADD in nonsmall cell lung cancer cells

Nonsmall cell lung cancer (NSCLC) is one of the most commonly diagnosed and lethal cancers characterized by relatively low overall cure and poor survival rates with great challenge for consistent effective clinical treatment. Here we demonstrated that the antifungal sertaconazole displays potent anti-NSCLC effect by promoting apoptosis in vitro and in vivo. Further studies found that sertaconazole induces complete autophagic flux, which contributes to sertaconazole-induced apoptosis and subsequent growth suppression in NSCLC cells. Further studies demonstrated that sertaconazole provokes TNF receptor type 1 associated death domain protein (TRADD) expression via stabilizing it from ubiquitination-mediated degradation, which results in Akt dephosphorylation and thereby triggers proapoptotic autophagy in NSCLC cells. Moreover, we found that TRADD suppression reverses sertaconazole-induced proapoptotic autophagy and relieves growth suppression, indicating the vital role of TRADD-regulated proapoptotic autophagy in the anti-NSCLC activity of sertaconazole. In summary, our findings suggest that sertaconazole could be a highly promising anti-NSCLC drug by triggering proapoptotic autophagy via stabilizing TRADD, which may provide a new potential therapeutic option for patients with NSCLC.

Chiral Benzothiophene Synthesis via Enantiospecific Coupling of Benzothiophene S-Oxides with Boronic Esters

Benzothiophenes are valuable heterocycles that are widely used in medicines, agrochemicals, and materials science. Herein, we report a general method for the synthesis of enantioenriched 2,3-disubstituted benzothiophenes via a transition-metal-free C2-alkylation of benzothiophenes with boronic esters. The reactions utilize benzothiophene S-oxides in lithiation-borylations to generate intermediate arylboronate complexes, and subsequent Tf₂ O-promoted S-O bond cleavage to trigger a Pummerer-type 1,2-metalate shift, which gives the coupled products with complete enantiospecificity. Primary, secondary and tertiary alkyl boronic esters and aryl boronic esters are successfully coupled with a range of C3-substituted benzothiophenes. Importantly, this transformation does not require the use of C3 directing groups, therefore it overcomes a major limitation of previously developed transition-metal-mediated C2 alkylations of benzothiophenes.

Polyhydroxyalkanoate/Antifungal Polyene Formulations with Monomeric Hydroxyalkanoic Acids for Improved Antifungal Efficiency

Novel biodegradable and biocompatible formulations of "old" but "gold" drugs such as nystatin (Nys) and amphotericin B (AmB) were made using a biopolymer as a matrix. Medium chain length polyhydroxyalkanoates (mcl-PHA) were used to formulate both polyenes (Nys and AmB) in the form of films (~50 µm). Thermal properties and stability of the materials were not significantly altered by the incorporation of polyenes in mcl-PHA, but polyene containing materials were more hydrophobic. These formulations were tested in vitro against a panel of pathogenic fungi and for antibiofilm properties. The films containing 0.1 to 2 weight % polyenes showed good activity and sustained polyene release for up to 4 days. A PHA monomer, namely 3-hydroxydecanoic acid (C10-OH), was added to the films to achieve an enhanced synergistic effect with polyenes against fungal growth. Mcl-PHA based polyene formulations showed excellent growth inhibitory activity against both Candida yeasts (C. albicans ATCC 1023, C. albicans SC5314 (ATCC MYA-2876), C. parapsilosis ATCC 22019) and filamentous fungi (Aspergillus fumigatus ATCC 13073; Trichophyton mentagrophytes ATCC 9533, Microsporum gypseum ATCC 24102). All antifungal PHA film preparations prevented the formation of a C. albicans biofilm, while they were not efficient in eradication of mature biofilms, rendering them suitable for the transdermal application or as coatings of implants.

Comparative efficacy evaluation of different penetration enhancement strategies for dermal delivery of poorly soluble drugs - A case with sertaconazole nitrate

The aim of this study was to compare the efficacy of different approaches for enhancement of dermal availability of the highly lipophilic antifungal model drug - sertaconazole nitrate (SN). For this purpose, a physical penetration enhancer - dissolving microneedles (MNs) was fabricated by filling moulds with liquid formulation based on polyvinylpyrrolidone and loaded with SN. Dissolving MNs were characterised regarding their morphological and mechanical characteristics. A penetration enhancement efficacy of MNs was evaluated in vitro using porcine ear skin in parallel with the efficacy of formerly developed chemical penetration enhancer - biocompatible microemulsion (ME) formulation. Moreover, an ability of solid silicon MNs to significantly improve delivery of SN from ME into the skin has also been investigated. The obtained results showed that dissolving MNs had satisfying morphological properties and mechanical strength. This type of MNs provided comparable drug deposition in the skin as ME formulation, but also revealed an indication of percutaneous absorption of a portion of the administered drug dose. However, the penetration/permeation study results were largely influenced by experimental setup and dosing regimen. Although solid silicon MNs assisted SN dermal delivery led to increase of drug cutaneous retention (1.9-fold) under infinite dosing regimen, the synergistic action of solid MNs and ME applied under finite dosing was more pronounced in comparison with the application either of physical (dissolving MNs) or chemical enhancer (ME) alone. Namely, SN amount accumulated into the skin increased up to 4.67 and 4.37 folds in comparison with ME and dissolving MNs alone, respectively, while reaching a significant decrease in drug permeation through the skin compared to the use of dissolving MNs. Application of ME per se was the only approach that provided selective in vitro dermal drug delivery without SN permeation across the skin. However, despite both types of the used MNs lead to SN permeation in vitro, the ratio between the drug amount deposited in the skin and SN content permeated was significantly higher for the combined approach (12.05) than for dissolving MNs (2.10). Therefore, a combination of solid silicon MNs and biocompatible ME favoured more pronouncedly SN skin accumulation, which is preferable in the treatment of skin fungal infections.

Antifungal therapy with azoles and the syndrome of acquired mineralocorticoid excess

The syndromes of mineralocorticoid excess describe a heterogeneous group of clinical manifestations leading to endocrine hypertension, typically either through direct activation of mineralocorticoid receptors or indirectly by impaired pre-receptor enzymatic regulation or through disturbed renal sodium homeostasis. The phenotypes of these disorders can be caused by inherited gene variants and somatic mutations or may be acquired upon exposures to exogenous substances. Regarding the latter, the symptoms of an acquired mineralocorticoid excess have been reported during treatment with azole antifungal drugs. The current review describes the occurrence of mineralocorticoid excess particularly during the therapy with posaconazole and itraconazole, addresses the underlying mechanisms as well as inter- and intra-individual differences, and proposes a therapeutic drug monitoring strategy for these two azole antifungals. Moreover, other therapeutically used azole antifungals and ongoing efforts to avoid adverse mineralocorticoid effects of azole compounds are shortly discussed.

Sertaconazole induced toxicity in HeLa cells through mitotic arrest and inhibition of microtubule assembly

Econazole, miconazole, and sertaconazole, the structurally related azoles with imidazole moiety, were evaluated for their cytotoxicity and their ability to bind to mammalian tubulin. Our results indicated that sertaconazole and econazole bound to goat brain tubulin with a dissociation constant of 9 and 19 μM respectively, while miconazole did not bind to goat brain tubulin. Econazole, miconazole, and sertaconazole inhibited the proliferation of HeLa cells with an IC₅₀ of 28, 98, and 38 μM respectively with sertaconazole alone inducing a mitotic block in the treated cells. Since sertaconazole bound to goat brain tubulin with higher affinity and blocked the cells at mitosis, we hypothesized that its cytotoxic mechanism might involve inhibition of tubulin and econazole which did not block the cells at mitosis may have additional targets than tubulin. Sertaconazole inhibited the polymerization of tubulin in HeLa cells and the in vitro assembled goat brain tubulin. Competitive tubulin-binding assay using colchicine and computational simulation studies showed that sertaconazole bound closer to the colchicine site and induced the tubulin dimer to adopt a "bent" conformation which is incompetent for the polymerization. Results from RT-PCR analysis of the A549 cells treated with sertaconazole indicated activation of apoptosis. Sertaconazole significantly inhibited the migration of HeLa cells and showed synergistic antiproliferative potential with vinblastine. Collectively, the results suggest that sertaconazole which is already in clinical practice could be useful as a topical chemotherapy agent for the treatment of skin cancers in combination with other systemic anticancer agents.

Gold-Catalyzed Intermolecular Alkyne Oxyarylation for C3 Functionalization of Benzothiophenes

C3-selective C-C bond formation on benzothiophenes is challenging, and few direct functionalization methods are available. A gold-catalyzed reaction of alkynes with benzothiophene S-oxides provides regioselective entry into C3-alkylated benzothiophenes with the C7-alkylated isomer as the minor product. This oxyarylation reaction works with alkyl and aryl alkynes and substituted and unsubstituted benzothiophenes. Mechanistic studies identify that sulfoxide inhibits the catalyst [DTBPAu(PhCN)]SbF₆, which also degrades and forms the unreactive complex [(DTBP)₂Au]SbF₆.

Recent Progress in the Synthesis of Benzo[b]thiophene

:

Due to such a wide range of applicability, the synthesis of benzo[b]thiophene derivatives has attracted intensive research. Numerous mild and efficient approaches for the synthesis of benzo[b]thiophenes have been developed over the years. Different catalysts and substrates have been applied for benzo[b]thiophene synthesis. This review will focus on the studies in the construction of benzo[b]thiophene skeleton, which date back from 2012.

One-step synthesis of benzo[b]thiophenes by aryne reaction with alkynyl sulfides

An aryne reaction with alkynyl sulfides affording benzo[b]thiophenes is disclosed. A wide range of 3-substituted benzothiophenes were synthesized from easily available o-silylaryl triflates and alkynyl sulfides in a one-step intermolecular manner. The synthesis of diverse multisubstituted benzothiophene derivatives involving a pentacyclic compound was achieved by virtue of the good functional group tolerance and versatile C2 functionalizations.

Antifungal efficacy of liquid poloxamer 407-based emulsions loaded with sertaconazole nitrate

Drug delivery into the human nail plate for the treatment of onychomycosis is difficult due to limited permeability of the nail plate. Semisolid poloxamer 407-based formulations have recently shown promising results for drug delivery into and through the nail plate. In this study, liquid poloxamer 407-based emulsions loaded with sertaconazole nitrate have been developed and the permeation behavior was determined in vitro using modified Franz diffusion cells. The antifungal efficacy was evaluated in an infected nail plate model, where the growth inhibition of Trichophyton rubrum was observed. Bovine hoof plates and keratin films made from human hair were used as models for the human nail plate. In both cases, formulations with low viscosity and high water content showed best results despite a lower solubility of sertaconazole nitrate, suggesting that the composition of the vehicle plays a major role in permeation through the membrane. In addition, an API content close to saturation solubility had a positive effect on permeation.

Low in vitro activity of sertaconazole against clinical isolates of dermatophyte

Background and Purpose:

Dermatophytes are a group of fungi specialized in invading humans and other vertebrate keratinized tissues. These fungi cause a variety of skin, nail, and hair disorders, called dermatophytosis (tinea). In some cases, drug resistance to antifungals necessitates special treatment. Among the antifungal agents, sertaconazole (i.e., a third-generation imidazole) has a broad-spectrum against dermatophyte species. Regarding this, the present study was conducted to investigate the antifungal susceptibility of dermatophytes obtained from patients with dermatophytosis in Mashhad located in northeastern Iran.

Materials and Methods:

A total of 75 clinical dermatophyte isolates, including Trichophyton mentagrophytes (n=21), T. interdigital (n=18), T. tonsurans (n=16), Epidermophyton floccosum (n=11), Microsporum canis (n=5), Nannizzia fulvum (n=2), T. benhamiae (n=1), and T. verrucosum (n=1), were evaluated against five antifungal agents of sertaconazole, itraconazole, clotrimazole, terbinafine, and griseofulvin based on the CLSI M38-A2 guideline.

Results:

According to the results, the minimum inhibitory concentration (MIC) ranges ofsertaconazole, terbinafine, griseofulvin, itraconazole, and clotrimazole were estimated at 0.125-16, 0.002-1, 0.5-4, 0.031-4, and 0.016-4 µg/ml, respectively, for dermatophyte species. In addition, the geometric mean (GM) values of the MIC of sertaconazole, terbinafine, griseofulvin, itraconazole, and clotrimazole were obtained as 3.39, 1, 1.44, 1.52, and 1.93, respectively.

Conclusion:

Among the tested antifungals, terbinafine and griseofulvin were the most effective agents against dermatophyte isolates. However, sertaconazole, a third-generation imidazole, did not show any significant effect. Furthermore, M. canis and E. floccosum showed the best response to the antifungal agents.

Synthesis, X-ray Single Crystal, Conformational Analysis and Cholinesterase Inhibitory Activity of a New Spiropyrrolidine Scaffold Tethered Benzo[b]Thiophene Analogue

Described herein is a one-pot protocol for the synthesis of a substituted spiropyrrolidine scaffold tethered benzo[b]thiophene analogue from (E)-3-(benzo[b]thiophen-2-yl)-1-(4-fluoro- phenyl)-prop-2-en-1-one. The described protocol has the advantage of the high purity of the cyclized adduct and high chemical yield. To assign the chemical structure, different spectrophotometric tools have been applied, including 1H-NMR, 13C-NMR, FTIR, and the X-ray single crystal technique. The X-ray structure showed that the studied compound exist in two disordered parts with equal partial occupancies. The energies of the two conformers were found to be very similar and not exceed 1 kcal/mol, which justifies their coexistence in the crystal with equal percentage. The molecular packing in the crystal was analyzed using Hirshfeld topology analysis. The packing described as two dimensional hydrogen bond network extended along the ac-plane in both conformers but the intermolecular interactions included in each conformer are not similar. The synthesized spiropyrrolidine scaffold tethered benzo[b]thiophene analogue was examined against cholinesterase inhibitory activity and show moderate activity compared to standard drug galantamine.

Chemistry and Pharmacology of Luliconazole (Imidazole Derivative): A Novel Bioactive Compound to Treat Fungal Infection-A Mini Review

Background:

Currently, ringworm treatment drugs include two major categories: first, propylene amine drugs, such as terbinafine, butenafine and naftifine, which exert their bactericidal effects through inhibiting squalene cyclase, causing the lack of ergosterol and accumulation of squalene. The second category of imidazole drugs includes miconazole, econazole, clotrimazole, ketoconazole and bifonazole.

Mechanism:

These synthetic antifungal agents exhibits their action by inhibiting the lanosterol 14α- demethylation activity of fungal cell, leading to the prevention of the ergosterol synthesis of cell membrane, changing the cell membrane permeability, and resulting in the loss of important intracellular fungal material and causing fungal death.

Applications:

At present, Imidazole antifungal agents are commonly used drugs in clinical treatment of ringworm with extensive clinical applications.

Conclusion:

The present review covers the chemistry and detailed pharmacology aspects of luliconazole.

A fully derivatized 4-chlorophenylcarbamate-β-cyclodextrin bonded chiral stationary phase for enhanced enantioseparation in HPLC

This paper reports an effective approach for the fabrication of a per-4-chlorophenylcarbamate-β-cyclodextrin (β-CD) bonded chiral stationary phase (CPCDP) in high-performance liquid chromatography. The morphology and structure of the ligand and the chiral stationary phase (CSP) were characterized by scanning electron microscopy, transmission electron microscopy, solid state ¹³C nuclear magnetic resonance spectra, fourier transform infrared spectra, elemental analysis and thermogravimetric analysis. Because CPCDP was a kind of multimode enantioseparation materials, the enantioseparation of chiral compounds including twelve azole antifungal agents, five proton pump inhibitors and five dihydropyridine calcium antagonists were studied in both reversed-phase and normal-phase chromatography. All analytes were obtained enantiomeric separation. Especially, the resolution of azoles was excellent. The selectivity and resolution of voriconazole reached 15.41 and 16.80, which was an exciting achievement for the enantioseparations by β-CD based chiral stationary phases. Compared with the commercial 3,5-dimethylphenyl carbamate-β-CD based chiral stationary phase (DMP), enhanced enantioselectivities for all the above compounds (except ilaprazole) were obtained on CPCDP column, which indicated that the 4-chlorophenylcarbamate group was conducive to the chiral recognition. Chromatographic studies elucidated that enhancement of analyte-chiral substrate interactions were attributed to the inclusion complexation, π-π stacking interaction, hydrogen-bonding, dipole-dipole interaction and steric hindrance. For further study, we also prepared semi-preparative chromatographic columns to obtain a single enantiomer. In addition to excellent chromatographic performance, the prepared CD-based column is stable and much cheaper than commercial columns, which can reduce the cost of test and has a good application prospect in chiral drug analysis.

A multicentre study of antifungal susceptibility patterns among 350 Candida auris isolates (2009-17) in India: role of the ERG11 and FKS1 genes in azole and echinocandin resistance

Background

Candida auris has emerged globally as an MDR nosocomial pathogen in ICU patients.

Objectives

We studied the antifungal susceptibility of C. auris isolates (n = 350) from 10 hospitals in India collected over a period of 8 years. To investigate azole resistance, ERG11 gene sequencing and expression profiling was conducted. In addition, echinocandin resistance linked to mutations in the C. auris FKS1 gene was analysed.

Methods

CLSI antifungal susceptibility testing of six azoles, amphotericin B, three echinocandins, terbinafine, 5-flucytosine and nystatin was conducted. Screening for amino acid substitutions in ERG11 and FKS1 was performed.

Results

Overall, 90% of C. auris were fluconazole resistant (MICs 32 to ≥64 mg/L) and 2% and 8% were resistant to echinocandins (≥8 mg/L) and amphotericin B (≥2 mg/L), respectively. ERG11 sequences of C. auris exhibited amino acid substitutions Y132 and K143 in 77% (n = 34/44) of strains that were fluconazole resistant whereas WT genotypes, i.e. without substitutions at these positions, were observed in isolates with low fluconazole MICs (1-2 mg/L) suggesting that these substitutions confer a phenotype of resistance to fluconazole similar to that described for Candida albicans. No significant expression of ERG11 was observed, although expression was inducible in vitro with fluconazole exposure. Echinocandin resistance was linked to a novel mutation S639F in FKS1 hot spot region I.

Conclusions

Overall, 25% and 13% of isolates were MDR and multi-azole resistant, respectively. The most common resistance combination was azoles and 5-flucytosine in 14% followed by azoles and amphotericin B in 7% and azoles and echinocandins in 2% of isolates.

Solutol HS15 based binary mixed micelles with penetration enhancers for augmented corneal delivery of sertaconazole nitrate: optimization, in vitro, ex vivo and in vivo characterization

Keratomycosis is a serious corneal disease that can cause a permanent visual disability if not treated effectively. Sertaconazole nitrate (STZ), a novel broad spectrum antifungal drug, was suggested as a promising treatment. However, its utility in the ocular route is restricted by its poor solubility, along with other problems facing the ocular delivery like short residence time, and the existing corneal barrier. Therefore, the objective of this study was to formulate STZ loaded binary mixed micelles (STZ-MMs) enriched with different penetration enhancers using thin-film hydration method, based on a 3¹.2² mixed factorial design. Different formulation variables were examined, namely, type of auxiliary surfactant, type of penetration enhancer, and total surfactants: drug ratio, and their effects on the solubility of STZ in MMs (S_M), particle size (PS), polydispersity index (PDI), and zeta potential (ZP) were evaluated. STZ-MMs enhanced STZ aqueous solubility up to 338.82-fold compared to free STZ. Two optimized formulations (MM-8 and MM-11) based on the desirability factor (0.891 and 0.866) were selected by Design expert^® software for further investigations. The optimized formulations were imaged by TEM which revealed nanosized spherical micelles. Moreover, they were examined for corneal mucoadhesion, stability upon dilution, storage effect, and ex vivo corneal permeation studies. Finally, both in vivo corneal uptake and in vivo corneal tolerance were investigated. MM-8 showed superiority in the ex vivo and in vivo permeation studies when compared to the STZ-suspension. The obtained results suggest that the aforementioned STZ loaded mixed micellar system could be an effective candidate for Keratomycosis-targeted therapy.

Synthesis of 2-substituted benzo[b]thiophenes via gold(i)-NHC-catalyzed cyclization of 2-alkynyl thioanisoles

Benzo[b]thiophene heterocycles are important components of many important small molecule pharmaceuticals and drug candidates as well as organic semiconducting materials. Many methods have been developed for the construction of a benzo[b]thiophene core via cyclization reaction of alkynes. Although few catalytic reactions were disclosed, most methods rely on stoichiometric activation of alkynes. Here we report an efficient method for the synthesis of 2-substituted benzo[b]thiophenes from 2-alkynyl thioanisoles catalyzed by a gold(i)-IPr hydroxide that is applicable to a wide range of substrates with diverse electronic and steric properties. Additionally, we demonstrate experimentally that the acid additive and its conjugate base are essential to catalyst turnover.

Molecular Modeling Studies of Halogenated Imidazoles against 14α- Demethylase from Candida Albicans for Treating Fungal Infections

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.

Corneal targeted Sertaconazole nitrate loaded cubosomes: Preparation, statistical optimization, in vitro characterization, ex vivo permeation and in vivo studies

Sertaconazole nitrate (STZ) is a poorly soluble antifungal drug commonly used for treating fungal skin infections. Introducing it as a new treatment option for the management of fungal keratitis, requires the development of a delivery system capable of targeting the infected cornea with an adequate STZ concentration. Hence, Sertaconazole nitrate loaded cubosomes (STZ-CUBs) were prepared, characterized and optimized based on a 3³ central composite face-centred design. Optimized formulation (CUB-opt) showed maximum desirability (0.905), with solubilization efficiency (SE%) of 94.50 ± 0.51%, particle size (PS) of 216.55 ± 2.33 nm, polydispersity index (PDI) of 0.229 ± 0.11 and zeta potential (ZP) of 34.00 ± 6.93 mV. Under the transmission electron microscope, it showed discrete cubic shaped structures. Moreover, it exhibited a promising mucoadhesive behavior, terminal sterilization stability, and storage stability. Ex vivo corneal permeation study revealed its ability to enhance the steady state flux (J_ss) and the permeability coefficient (K_P) of STZ, compared to STZ-suspension. Finally, CUB-opt formulation was found to be safe on the corneal tissues in the in vivo corneal tolerance study, and demonstrated a superior corneal penetration power in the in vivo corneal uptake study.

Regioselective Metal- and Reagent-Free Arylation of Benzothiophenes by Dehydrogenative Electrosynthesis

A novel strategy for the synthesis of biaryls consisting of a benzothiophene and a phenol moiety is reported. These heterobiaryls are of utmost interest for pharmaceutical, biological, and high-performance optoelectronic applications. The metal- and reagent-free, electrosynthetic, and highly efficient method enables the generation of 2- and 3-(hydroxyphenyl)benzo[b]thiophenes in a regioselective fashion. The described one-step synthesis is easy to conduct, scalable, and inherently safe. The products are afforded in high yields of up to 88 % and with exquisite selectivity. The reaction also features a broad scope and tolerates a large variety of functional groups.

Antifungal activity of Cardiospermum halicacabum L. (Sapindaceae) against Trichophyton rubrum occurs through molecular interaction with fungal Hsp90

Introduction

Dermatophytosis is a superficial fungal infection limited to the stratum corneum of the epidermis, or to the hair and nails, and constitutes an important public health problem because of its high prevalence and associated morbidity. Dermatophyte fungi, especially 2 species, Trichophyton rubrum and Trichophyton mentagrophytes, are the predominant pathogens. Topical antifungal drugs, mainly azoles or allyamines, are currently used for the treatment of dermatophytoses, although in some cases, such as in nail and hair involvement, systemic treatment is required. However, therapeutic efficacy of current antifungal agents can be limited by their side effects, costs, and the emergence of drug resistance among fungi. Plant extracts represent a potential source of active antimicrobial agents, due to the presence of a variety of chemical bioactive compounds. In the present work, we evaluated in silico and in vitro the antifungal activity of an extract of the medicinal plant Cardiospermum halicacabum against T. rubrum suggesting a potential interaction with Hsp90 as playing an important role in both pathogenicity and drug susceptibility of T. rubrum.

Methods

We investigated in vitro the effect of different concentrations of C. halicacabum (from 500 to 31.25 µg) against a clinical isolate of T. rubrum. Furthermore, using a computational assessment, the interaction between different C. halicacabum active compounds and the fungal Hsp90 was also investigated.

Results

Our results indicate a clear-cut antifungal activity of the total plant extract at the highest concentrations (500 and 250 µg). Among all tested C. halicacabum compounds, the luteolin and rutin molecules have been identified in silico as the most important potential inhibitors of Hsp90. Based on these data, luteolin and rutin were also individually assessed for their antifungal activity. Results demonstrate that both substances display an antifungal effect, even if lower than that of the total plant extract.

Conclusion

Our data indicate a strong fungistatic effect of C. halicacabum against T. rubrum, suggesting its potential therapeutic efficacy in the treatment of dermatophytoses. Additionally, C. halicacabum compounds, and particularly luteolin and rutin, are all possible Hsp90 interactors, explaining their fungistatic activity.

Safety and efficacy of a new imidazole fungicide, Sertaconazole, in the treatment of fungal vulvo-vaginitis: a comparative study using Fluconazole and Clotrimazole

Background: Sertaconazole is a new imidazole fungicide introduced for vulvo-vaginal candidiasis. It has an azole group with benzothiophene that inhibits biosynthesis of ergosterol and brings about a massive leak of cytoplasm with consequent fungal cell death. Objective: Assess the safety and efficacy of Sertaconazole in the treatment of fungal vulvo-vaginitis for comparison with Fluconazole and Clotrimazole. Subjects and methods: One-hundred eighty-eight outpatients with fungal vulvo-vaginitis were recruited at Siriraj Hospital, Thailand between August 31, 2004 and January 30, 2006. The patients were given Sertaconazole, Fluconazole, or Clotrimazole, and received vaginal swab and culture for fungus at seventh and 28th days after treatment. Results: Out of 188 cases, 177 cases were followed-up completely. Sertaconazole group included 66 cases where 35 cure, 20 fail, and 7 recurrent cases. Fluconazole group included 60 cases and had 37 cure, six fail, and 20 recurrence cases. Clotrimazole group included 55 cases and had 32 cure, nine fail and 11 recurrent cases. There were risk factors of fungal vulvo-vaginitis, including frequent micturition and small toilet shower flushing. Conclusion: Sertaconazole had similar effectiveness and less side-effect as compared with Fluconazole and Clotrimazole. It appeared to work well with lowest recurrence.

Unmasking Dipole Character of Acyl Ketene Dithioacetals via a Cascade Reaction with Arynes: Synthesis of Benzo[b]thiophenes

An unusual strategy toward novel substituted benzo[b]thiophenes has been developed. The generation of arynes in the presence of acyl ketene dithioacetals resulted in a cascade reaction involving [3 + 2] cycloaddition, and a dealkylative arylation of a thioether moiety to afford 2,3-disubstuted benzo[b]thiophenes. This route represents an expeditious approach to benzothiophenes that employs acyl ketene dithioacetals as dipoles.

Efficacy and tolerability of topical sertaconazole versus topical terbinafine in localized dermatophytosis: A randomized, observer-blind, parallel group study

OBJECTIVE

Epidermal dermatophyte infections most commonly manifest as tinea corporis or tinea cruris. Topical azole antifungals are commonly used in their treatment but literature suggests that most require twice-daily application and provide lower cure rates than the allylamine antifungal terbinafine. We conducted a head-to-head comparison of the effectiveness of the once-daily topical azole, sertaconazole, with terbinafine in these infections.

MATERIALS AND METHODS

We conducted a randomized, observer-blind, parallel group study (Clinical Trial Registry India [CTRI]/2014/09/005029) with adult patients of either sex presenting with localized lesions. The clinical diagnosis was confirmed by potassium hydroxide smear microscopy of skin scrapings. After baseline assessment of erythema, scaling, and pruritus, patients applied either of the two study drugs once daily for 2 weeks. If clinical cure was not seen at 2 weeks, but improvement was noted, application was continued for further 2 weeks. Patients deemed to be clinical failure at 2 weeks were switched to oral antifungals.

RESULTS

Overall 88 patients on sertaconazole and 91 on terbinafine were analyzed. At 2 weeks, the clinical cure rates were comparable at 77.27% (95% confidence interval [CI]: 68.52%-86.03%) for sertaconazole and 73.63% (95% CI 64.57%-82.68%) for terbinafine (P = 0.606). Fourteen patients in either group improved and on further treatment showed complete healing by another 2 weeks. The final cure rate at 4 weeks was also comparable at 93.18% (95% CI 88.75%-97.62%) and 89.01% (95% CI 82.59%-95.44%), respectively (P = 0.914). At 2 weeks, 6 (6.82%) sertaconazole and 10 (10.99%) terbinafine recipients were considered as "clinical failure." Tolerability of both preparations was excellent.

CONCLUSION

Despite the limitations of an observer-blind study without microbiological support, the results suggest that once-daily topical sertaconazole is as effective as terbinafine in localized tinea infections.

Commercial Essential Oils as Potential Antimicrobials to Treat Skin Diseases

Essential oils are one of the most notorious natural products used for medical purposes. Combined with their popular use in dermatology, their availability, and the development of antimicrobial resistance, commercial essential oils are often an option for therapy. At least 90 essential oils can be identified as being recommended for dermatological use, with at least 1500 combinations. This review explores the fundamental knowledge available on the antimicrobial properties against pathogens responsible for dermatological infections and compares the scientific evidence to what is recommended for use in common layman's literature. Also included is a review of combinations with other essential oils and antimicrobials. The minimum inhibitory concentration dilution method is the preferred means of determining antimicrobial activity. While dermatological skin pathogens such as Staphylococcus aureus have been well studied, other pathogens such as Streptococcus pyogenes, Propionibacterium acnes, Haemophilus influenzae, and Brevibacterium species have been sorely neglected. Combination studies incorporating oil blends, as well as interactions with conventional antimicrobials, have shown that mostly synergy is reported. Very few viral studies of relevance to the skin have been made. Encouragement is made for further research into essential oil combinations with other essential oils, antimicrobials, and carrier oils.

Regioselective synthesis of C3 alkylated and arylated benzothiophenes

Benzothiophenes are heterocyclic constituents of important molecules relevant to society, including those with the potential to meet modern medical challenges. The construction of molecules would be vastly more efficient if carbon-hydrogen bonds, found in all organic molecules, can be directly converted into carbon-carbon bonds. In the case of elaborating benzothiophenes, functionalization of carbon-hydrogen bonds at carbon-number 3 (C3) is markedly more demanding than at C2 due to issues of regioselectivity (C3 versus C2), and the requirement of high temperatures, precious metals and the installation of superfluous directing groups. Herein, we demonstrate that synthetically unexplored but readily accessible benzothiophene S-oxides serve as novel precursors for C3-functionalized benzothiophenes. Employing an interrupted Pummerer reaction to capture and then deliver phenol and silane coupling partners, we have discovered a directing group-free method that delivers C3-arylated and -alkylated benzothiophenes with complete regioselectivity, under metal-free and mild conditions.