Fluorine Substituents Research Articles

Effect of semifluoroalkyl substituents in the POSS on atomic oxygen exposure

Due to the many recent Earth observation missions, very low Earth orbit (VLEO) have become a pressing topic for satellite research. Since the density of atomic oxygen (AO) in VLEO is higher than in low Earth orbit (LEO), the need for AO-resistant materials based on polyhedral oligomeric silsesquioxane (POSS) is strong. However, the effects of the side-chain groups in the POSS on AO exposure are unclear. In this study, we focused on POSS molecules modified with semifluoroalkyl groups as side chains because fluorocarbon groups, such as fluorinated ethylene propylene (FEP), are known to have high AO resistance. Semifluoroalkyl- and alkyl-substituted POSS films were fabricated and exposed to a laser-detonation AO source. Microbalance measurements showed that the mass losses of the semifluoroalkyl-substituted POSS films were larger than those of alkyl-substituted POSS films. X-ray photoelectron spectroscopy measurements showed that the silica layers formed on the semifluoroalkyl-substituted POSS were thicker than on alkyl-substituted POSS films. Surface observation using a field emission scanning electron microscope revealed microscale cracks on the surface of the semifluoroalkyl-substituted POSS. These findings indicate that POSS molecules with fluorine substituents warrant careful consideration of the AO-barrier performance of the silica layer formed during AO exposure.

Tailoring iron hexadecafluorophthalocyanine/GO nanocomposite separators for polysulfide adsorption and enabling fast electrochemical kinetics of Li-S batteries

The cycling stability of lithium-sulfur batteries is significantly compromised by the shuttle effect. Herein, we employed a preformed process to successfully load spherical nanoparticles of Iron hexadecafluorophthalocyanine (FePcF16) with sizes between 10 and 20 nm onto oxidized graphene sheets. The FePcF16 spherical particles with lithium and sulfur-affinitive sites maximally expose catalytically active sites, facilitating effective adsorption and catalysis of polysulfides (LiPSs). Density-functional theory (DFT) calculations suggest that the electron-rich fluorine substituents enhance the conjugation effect of FePcF16, facilitating electronic communication between the catalyst and graphene oxide (GO), achieving precise modulation of the electronic structure of Fe-N4 active centers. The electrochemical analysis demonstrates that the nanostructured and Fe-N4 site-containing FePcF16 integrated with the robust two-dimensional graphene structure synergistically facilitates both redox reactions and lithium affinity effects. Consequently, in extended cycling tests at 2 C, the initial discharge-specific capacity reached 857.7 mAh g−1. After 500 cycles, the capacity remained at 737.7 mAh g−1, with a minimal capacity decay rate of only 0.028 % per cycle.

Discovery of membrane-targeting amphiphilic honokiol derivatives containing an oxazolethione moiety to combat methicillin-resistant Staphylococcus aureus (MRSA) infections

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major pathogen causing infections in hospitals and the community, and there is an urgent need for the development of novel antibacterials to combat MRSA infections. Herein, a series of amphiphilic honokiol derivatives containing an oxazolethione moiety were prepared and evaluated for their in vitro antibacterial and hemolytic activities. The screened optimal derivative, I3, exhibited potent in vitro antibacterial activity against S. aureus and clinical MRSA isolates with MIC values of 2–4 μg/mL, which was superior to vancomycin in terms of its rapid bactericidal properties and was less susceptible to the development of resistance. The SARs analysis indicated that amphiphilic honokiol derivatives with fluorine substituents had better antibacterial activity than those with chlorine and bromine substituents. In vitro and in vivo toxicity studies revealed that I3 has relatively low toxicity. In a MRSA-infected mouse skin abscess model, I3 (5 mg/kg) effectively killed MRSA at the infected site and attenuated the inflammation effects, comparable to vancomycin. In a MRSA-infected mouse sepsis model, I3 (12 mg/kg) was found to significantly reduce the bacterial load in infected mice and increase survival of infected mice. Mechanistic studies indicated that I3 has membrane targeting properties and can interact with phosphatidylglycerol (PG) and cardiolipin (CL) of MRSA cell membranes, thereby disrupting MRSA cell membranes, further inducing the increase of reactive oxygen species (ROS), protein and DNA leakage to achieve rapid bactericidal effects. Finally, we hope that I3 is a potential candidate molecule for the development of antibiotics to conquer superbacteria-related infections.

Preferential Binding to a Mannoside of a Pyridine–Acetylene–Phenol Macrocycle with a Fluorine Substituent in the Cavity

We developed a pyridine–acetylene–phenol macrocycle in which a fluorine atom was introduced in place of a hydroxy group, as a host for the selective binding to epimers of glucose. The fluorine atom was expected to work as a negatively charged infill repelling oxygen atoms of saccharides andprevent the efficient formation of a hydrogen‐bond network with a glucoside, whose cross‐section size is larger than those of the corresponding epimers, especially of a mannoside. UV−Vis and fluorescence titration experiments revealed that this host showed a higher affinity for a mannoside than a glucoside. 1H NMR and molecular modeling suggested that the fluorine atom acts as a moderate infill weakening the binding to a glucoside.This result indicates that selectivity for guest molecules can be modified by replacing a hydroxy group and a hydrogen atom in host molecules with a fluorine atom.

Recent Advances in the Synthesis of N-fluoroalkyl Amides/Sulfonamides and Their Carbonyl/Sulfonyl Derivatives.

Organofluorine compounds have consistently demonstrated practical applications in the life sciences due to the fascinating properties imparted by the fluorine substituents. In recent years, significant advancements have been made in the synthesis of N-fluoroalkyl carbonyl and sulfonyl compounds. This review offers a current overview of the various synthetic routes for N-fluoroalkyl amides/sulfonamides and their transformation to new unexplored N-fluoroalkyl carbonyl/sulfonyl derivatives, categorized into three parts based on the different fluoroalkyl groups.

Oxygen Atom Stabilization by a Main-Group Lewis Acid: Observation and Characterization of an OBeF2 Complex with a Triplet Ground State.

Terminal oxygen radicals involving p- and d-block atoms are quite common, but s-block compounds with an oxygen radical character remain rare. Here, we report that alkaline-earth metal beryllium atoms react with OF2 to form the oxygen beryllium fluorides OBeF and OBeF2. These species are characterized by matrix-isolation infrared spectroscopy with isotopic substitution and quantum-chemical calculations. The linear molecule OBeF has a 2Π ground state with an oxyl radical character. The 3A2 (C2v) ground state of OBeF2 represents the unusual case of a triplet oxygen atom stabilized by a relatively weak interaction by the Lewis acidic BeF2. The interaction involves both a donor component from oxygen to empty Be orbitals and a back-bonding contribution from fluorine substituents toward oxygen.

Transferrin Receptor-Mediated Cellular Uptake of Fluorinated Chlorido[N,N'-bis(salicylidene)-1,2-phenylenediamine]iron(III) Complexes.

Fluorinated chlorido[salophene]iron(III) complexes (salophene = N,N'-bis(salicylidene)-1,2-phenylenediamine) are promising anticancer agents. Apoptosis and necrosis induction have already been described as part of their mode of action. However, the involvement of ferroptosis in cell death induction, as confirmed for other chlorido[salophene]iron(III) complexes, has not yet been investigated. Furthermore, the mechanism of cellular uptake of these compounds is unknown. Therefore, the biological activity of the fluorescent chlorido[salophene]iron(III) complexes with a fluorine substituent at positions 3, 4, 5, or 6 at the salicylidene moieties (C1-C4) was evaluated in malignant and nonmalignant cell lines with focus on the involvement of the transferrin receptor-1 (TfR-1) in cellular uptake, the influence of the complexes on mitochondrial function, and the analysis of the molecular mechanism of cell death. All complexes significantly decreased the metabolic activity in the tested ovarian cancer (A2780, A2780cis), breast cancer (MDA-MB 231), and leukemia (HL-60) cell lines, while the nonmalignant human stroma cell line HS-5 at a concentration of 0.5 μM, which represents the IC50 of the complexes in most of the used tumorigenic cell lines, was not affected. The mitochondrial function was impaired, as evidenced by a reduced mitochondrial membrane potential ΔΨm and decreased mitochondrial activity. Besides apoptosis and necroptosis, ferroptosis was identified as part of the mode of action. It was further demonstrated for the first time that fluorinated chlorido[salophene]iron(III) complexes downregulate TfR-1 expression, comparable to ferristatin II, an iron transport inhibitor that acts via TfR-1 degradation. FerroOrange staining further indicated that the complexes strongly increased the intracellular iron(II) level as a driving force to induce ferroptosis. In conclusion, these fluorinated chlorido[salophene]iron(III) complexes are potent, tumor cell-specific chemotherapeutic agents, with the potential to treat various types of cancers.

Total synthesis of Comfreyn A and structural analogues via two photochemical key steps.

In this work the influence of o-fluorine substituents on the photo-dehydro-Diels-Alder (PDDA) reaction was investigated and the findings of this study were applied to the total synthesis of natural products. The reactant molecules consisted of two alkyl arylpropiolates, connected by a suberic acid tether and bearing fluorine substituents in each of the o-positions. While quantum chemical calculations suggested that a fluorine substituent prevents an attack of the adjacent carbon atom in the second C-C bond forming step of the PDDA reaction, this attack took place nevertheless. The subsequent fluoride elimination, assisted by protic solvents or trialkylsilanes, resulted in an "Umpolung" of the 4-position of the cycloallene intermediate enabling the introduction of nucleophiles at this position. The nucleophilic replacement of the second fluorine substituent could also be triggered photochemically. After removal of the tether, the two arene moieties stand nearly perpendicular to each other and a selective excitation of the naphthalene moiety was possible. This led to an intramolecular photoinduced electron transfer (PET) followed by a nucleophilic replacement of the fluoride according to a SR+N1Ar* mechanism. The formed phenolic hydroxyl group underwent spontaneous lactonization with the adjacent ester group. Based on these results, the first total synthesis of the lignan Comfreyn A and some structural analogues were developed.

Boosting Organic Solar Cells to Over 18% Efficiency through Dipole-Dipole Interactions in Fluorinated Nonfused Ring Electron Acceptors.

This study successfully designed and synthesized two nonfused ring electron acceptors, 412-6F and 412-6Cl, modified with fluorine and chlorine substituents, respectively. Single-crystal analysis revealed that 412-6F possesses a planar molecular backbone and exhibits pronounced dipole-dipole interactions between the fluorine atoms on the lateral phenyl groups and the carbonyl oxygen atoms on the end groups. This specific interaction promotes dense end-group stacking, leading to a reduced interlayer spacing. Improved crystallinity and coherence length are observed in the D18:412-6F blend film. Conversely, 412-6Cl adopts a more distorted configuration and lacks these interactions. As a result, the organic solar cell (OSC) based on D18:412-6F achieved a remarkable power conversion efficiency of 18.03%, surpassing the performance of the D18:412-6Cl OSC. This underscores the importance of designing novel acceptors with beneficial intermolecular interactions to enhance OSC efficiency, thus providing a new direction for organic photovoltaic advancement.

New Series of Hydrogen-Bonded Liquid Crystal with High Birefringence and Conductivity.

Liquid crystals with high dielectric anisotropy, low operational thresholds, and significant birefringence (Δn) represent a key focus in soft matter research. This work introduces a novel series of hydrogen-bonded liquid crystals (HBLCs) derived from 4-n-alkoxybenzoic, 4-alkoxy-3-fluorobenzoic derivatives (nOBAF), 4-alkoxy-2,3-fluorobenzoic derivatives (nOBAFF), and 2-fluoro-4-nitrobenzoic acid. The HBLCs were characterized using Fourier transform infrared spectroscopy, and their thermal behavior was evaluated via differential scanning calorimetry. Optical observations were conducted using polarized optical microscopy. The results indicate that mixtures containing benzoic acid with a bilateral fluorine substituent exhibit both SmA and SmC phases, while those with a unilateral fluorine substituent exhibit nematic and SmA phases. Moreover, an increase in the length of the alkoxy chain results in an expanded mesophase temperature range. This study demonstrates that the presence of a fluorine substituent and the incorporation of an NO2 group in the molecular structure result in an increase in dielectric permittivity, DC conductivity, dielectric anisotropy, and birefringence.

Synthesis, mol-ecular and crystal structures of 4-amino-3,5-di-fluoro-benzo-nitrile, ethyl 4-amino-3,5-di-fluoro-benzoate, and diethyl 4,4'-(diazene-1,2-di-yl)bis-(3,5-di-fluoro-benzoate).

The crystal structures of two inter-mediates, 4-amino-3,5-di-fluoro-benzo-nitrile, C7H4F2N2 (I), and ethyl 4-amino-3,5-di-fluoro-benzoate, C9H9F2NO2 (II), along with a visible-light-responsive azo-benzene derivative, diethyl 4,4'-(diazene-1,2-di-yl)bis-(3,5-di-fluoro-benzoate), C18H14F4N2O4 (III), obtained by four-step synthetic procedure, were studied using single-crystal X-ray diffraction. The mol-ecules of I and II demonstrate the quinoid character of phenyl rings accompanied by the distortion of bond angles related to the presence of fluorine substituents in the 3 and 5 (ortho) positions. In the crystals of I and II, the mol-ecules are connected by N-H⋯N, N-H⋯F and N-H⋯O hydrogen bonds, C-H⋯F short contacts, and π-stacking inter-actions. In crystal of III, only stacking inter-actions between the mol-ecules are found.

Vapor pressure of tetrasubstituted metal phthalocyanines bearing fluorine substituents in non-peripheral positions

In this paper, the temperature dependence of the saturated vapor pressure of fluorosubstituted phthalocyanines with substituents in non-peripheral positions of the macroring, viz. MPcF4-np, M=Cu, Fe, Co, VO, was investigated by the Knudsen effusion method with mass spectrometric registration of the gaseous phase composition. The standard thermodynamic parameters [Formula: see text]°[Formula: see text] and [Formula: see text]°[Formula: see text] of the sublimation process of these compounds were determined. The results were compared with the vapor pressure of the corresponding MPcF4-p analogs bearing F-substituents in the peripheral positions. It was shown that the volatility decreased in the order of VOPcF4-np > CoPcF4-np ∼ CuPcF4-np ∼ FePcF4-np > ZnPcF4-np, which correlated with the increase in their crystal lattice energy in the same order. The volatility of most MPcF4-np (M = Cu, Zn, Co, VO) was lower than that of MPcF4-p. The results were analyzed from the point of view of crystal packing and intermolecular interactions in the crystal.

Acidity of saturated (hetero)cyclic α-fluoro carboxylic acids and lipophilicity of their amide derivatives

Analysis of the physicochemical parameters of saturated (hetero)cyclic carboxylic acids and their α-fluorinated analogues is described. Measured pKa values revealed a significant influence of the single fluorine substituent on the compound's acidity (pKa decreased by 1.3–2.4 units). This effect did not demonstrate additivity with electronic effects of other heteroatom (i.e., cyclic ether moiety). On the contrary, lipophilicity (LogP) of the corresponding anilides was almost unaffected upon α-substitution with a fluorine atom and mainly governed by the nature of the (hetera)cycloalkyl substituent. The obtained results suggest that polarization of the C–F bonds themselves does not define the fluorine effect on the compound's lipophilicity.

3d-metal macrocyclic complexes containing porphyrazine/ perfluoroporphyrazine and fluoro ligands: Structural and thermodynamic parameters according to the various DFT model chemistries

By using three independent of density functional theory (DFT) model chemistries with functionals B3PW91, M06 and OPBE, and the TZVP basis set, combining the D3 version of Grimme’s dispersion with the original D3 damping function, the molecular structures of three types of 3[Formula: see text] element (M) macrocyclic coordination compounds — homoligand with porphyrazine (H2L1), heteroligand with porphyrazine and two axially oriented fluoro ligands and heteroligand with perfluoroporphyrazine (H2L2) and two axially oriented fluoro ligands having [ML1], [ML1(F)2] and [ML2(F)2] compositions, respectively, were calculated. The values of the most important bond lengths, bond and non-bond angles in the resulting metal complexes, and NBO analysis data are presented. It was noted that almost each of these complexes contains a coplanar MN4 chelate unit and a group of N4 atoms, as well as coplanar 5- and 6-membered rings; moreover, both of them are pairwise identical to each other in terms of the sums of bond angles (540[Formula: see text] and 720[Formula: see text], respectively) and their assortments. Bond angles formed by M atoms and two fluorine atoms are 180[Formula: see text]; bond angles formed by fluorine, M and nitrogen atoms are 90[Formula: see text]. NBO analysis of all the above 3[Formula: see text]-metal chelates was carried out, and based on the data, a high degree of delocalization of the electron density in these coordination compounds was stated. The values of the standard enthalpy [Formula: see text], entropy [Formula: see text] and Gibbs energy [Formula: see text] of formation of these compounds were also calculated. Particular attention was paid to the fact that according to these data, for the ([ML1]) and ([ML1(F)2]) complexes the values of [Formula: see text] and [Formula: see text] are positive, whereas for ([ML2(F)2]) complexes they are negative, and in the series [ML1] – [ML1(F)2] – [ML2(F)2] there is an increase in the thermodynamic stability of the complexes, which is undoubtedly due to the presence of peripheral fluorine substituents in the [ML2(F)2] structure. There was also good agreement between similar parameters calculated by different DFT methods, both qualitatively and quantitatively.

Effect of substituents at the C3´, C3´N, C10 and C2-meta-benzoate positions of taxane derivatives on their activity against resistant cancer cells

We tested the effect of substituents at the (1) C3´, C3´N, (2) C10, and (3) C2-meta-benzoate positions of taxane derivatives on their activity against sensitive versus counterpart paclitaxel-resistant breast (MCF-7) and ovarian (SK-OV-3) cancer cells. We found that (1) non-aromatic groups at both C3´ and C3´N positions, when compared with phenyl groups at the same positions of a taxane derivative, significantly reduced the resistance of ABCB1 expressing MCF-7/PacR and SK-OV-3/PacR cancer cells. This is, at least in the case of the SB-T-1216 series, accompanied by an ineffective decrease of intracellular levels in MCF-7/PacR cells. The low binding affinity of SB-T-1216 in the ABCB1 binding cavity can elucidate these effects. (2) Cyclopropanecarbonyl group at the C10 position, when compared with the H atom, seems to increase the potency and capability of the derivative in overcoming paclitaxel resistance in both models. (3) Derivatives with fluorine and methyl substituents at the C2-meta-benzoate position were variously potent against sensitive and resistant cancer cells. All C2 derivatives were less capable of overcoming acquired resistance to paclitaxel in vitro than non-substituted analogs. Notably, fluorine derivatives SB-T-121205 and 121,206 were more potent against sensitive and resistant SK-OV-3 cells, and derivatives SB-T-121405 and 121,406 were more potent against sensitive and resistant MCF-7 cells. (4) The various structure-activity relationships of SB-T derivatives observed in two cell line models known to express ABCB1 favor their complex interaction not based solely on ABCB1.

Wide Bandgap Polymer Donors Based on Succinimide-Substituted Thiophene for Nonfullerene Organic Solar Cells.

The advent of nonfullerene acceptors (NFAs) has greatly improved the photovoltaic performance of organic solar cells (OSCs). However, to compete with other solar cell technologies, there is a pressing need for accelerated research and development of improved NFAs as well as their compatible wide bandgap polymer donors. In this study, a novel electron-withdrawing building block, succinimide-substituted thiophene (TS), is utilized for the first time to synthesize three wide bandgap polymer donors: PBDT-TS-C5, PBDT-TSBT-C12, and PBDTF-TSBT-C16. These polymers exhibit complementary bandgaps for efficient sunlight harvesting and suitable frontier energy levels for exciton dissociation when paired with the extensively studied NFA, Y6. Among these donors, PBDTF-TSBT-C16 demonstrates the highest hole mobility and a relatively low highest occupied molecular orbital (HOMO) energy level, attributed to the incorporation of thiophene spacers and electron-withdrawing fluorine substituents. OSC devices based on the blend of PBDTF-TSBT-C16:Y6 achieve the highest power conversion efficiencyof 13.21%, with a short circuit current density (Jsc) of 26.83mA cm-2, an open circuit voltage (Voc) of 0.80V, and a fill factorof 0.62. Notably, the Voc × Jsc product reaches 21.46mW cm-2, demonstrating the potential of TS as an electron acceptor building block for the development of high-performance wide bandgap polymer donors in OSCs.

The efficiency of a granular Fe-based metal-organic framework for the persulfate oxidative degradation of levofloxacin, an emerging antibiotic in wastewater

This study presents a novel approach to solve the problems of leaching and regeneration of metal–organic frameworks (MOFs) in water treatment. The researchers developed a modified MOF by encapsulating MIL-88(Fe) with alginate. The modified MOF was then used to activate sulfate radicals with sodium persulfate for the degradation of levofloxacin (LVX) in water. Various characterization techniques, including XRD, FTIR, BET, FESEM, TG and EDS mapping, confirmed the successful synthesis of the modified MOF and revealed its characteristic facets. The catalytic and adsorptive abilities of the modified MOFs were investigated and sodium persulfate was found to be more effective than hydrogen peroxide in the degradation of LVX. Optimal degradation conditions were determined at a pH of 3, a concentration of 2.5 mM Na2S2O8 and a catalyst dosage of 0.75 g/L. The researchers also found that higher temperatures improved the removal of LVX. The granulated MOF showed remarkable stability over five cycles, although the performance gradually decreased, indicating its potential for long-term applications in water treatment. The inhibitory properties of isopropyl alcohol and ethanol suggest that sulfate radicals rather than hydroxyl radicals are involved in the degradation of LVX. In addition, the functional groups of levofloxacin, including the piperazine ring, the carboxylic acid group and the fluorine substituents, were identified as potential initiation sites for oxidation.

Degradation of quinolone antibiotics by freeze activated periodate: effect of the number of fluorine substituents and DFT calculations

Degradation of quinolone antibiotics by freeze activated periodate: effect of the number of fluorine substituents and DFT calculations

Fluoro and Trifluoromethyl Benzoyl Hypoiodite Complexes with Substituted Pyridines.

Based on the prior observation of the trifluoroacetate hypoiodite, CF3C(O)OI, demonstrating the largest σ-hole of a neutral halogen bond donor, a series of mono- and bis-carbonyl hypoiodites utilising trifluoromethyl or fluorine substituents at various positions of a parent benzoyl skeleton have been synthesised. The carbonyl hypoiodite complexes were prepared via cation exchange of the silver(I) cations with iodine(I) from the respective silver(I) carboxylates and dicarboxylates as the synthetic precursors. A range of pyridinic Lewis bases of varying nucleophilicities were used to stabilise the carbonyl hypoiodites to further probe their properties. The silver(I) intermediates with these Lewis bases were also isolated for silver(I) pentafluorobenzoate, providing additional insight into the cation exchange reaction. All complexes were characterised both in solution (1H, 1H-15N HMBC, 19F) and in the solid state (SCXRD), permitting insights into the formation of the elusive pyridine-iodine(I) cation.

Exploring the potential of bis(thiazol-5-yl)phenylmethane derivatives as novel candidates against genetically defined multidrug-resistant Staphylococcus aureus.

Antimicrobial resistance (AMR) represents an alarming global challenge to public health. Infections caused by multidrug-resistant Staphylococcus aureus (S. aureus) pose an emerging global threat. Therefore, it is crucial to develop novel compounds with promising antimicrobial activity against S. aureus especially those with challenging resistance mechanisms and biofilm formation. Series of bis(thiazol-5-yl)phenylmethane derivatives were evaluated against drug-resistant Gram-positive bacteria. The screening revealed an S. aureus-selective mechanism of bis(thiazol-5-yl)phenylmethane derivatives (MIC 2-64 μg/mL), while significantly lower activity was observed with vancomycin-resistant Enterococcus faecalis (MIC 64 μg/mL) (p<0.05). The most active phenylmethane-based (p-tolyl) derivative, 23a, containing nitro and dimethylamine substituents, and the naphthalene-based derivative, 28b, harboring fluorine and nitro substituents, exhibited strong, near MIC bactericidal activity against S. aureus with genetically defined resistance phenotypes such as MSSA, MRSA, and VRSA and their biofilms. The in silico modeling revealed that most promising compounds 23a and 28b were predicted to bind S. aureus MurC ligase. The 23a and 28b formed bonds with MurC residues at binding site, specifically Ser12 and Arg375, indicating consequential interactions essential for complex stability. The in vitro antimicrobial activity of compound 28b was not affected by the addition of 50% serum. Finally, all tested bis(thiazol-5-yl)phenylmethane derivatives showed favorable cytotoxicity profiles in A549 and THP-1-derived macrophage models. These results demonstrated that bis(thiazol-5-yl)phenylmethane derivatives 23a and 28b could be potentially explored as scaffolds for the development of novel candidates targeting drug-resistant S. aureus. Further studies are also warranted to understand in vivo safety, efficacy, and pharmacological bioavailability of bis(thiazol-5-yl)phenylmethane derivatives.