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The Journal of Organic Chemistry Jun 2024Here, a novel iodine-catalyzed direct cyclization of -nitrothiophenols with cyclohexanones to phenothiazines has been described without external oxidants and hydrogen...
Here, a novel iodine-catalyzed direct cyclization of -nitrothiophenols with cyclohexanones to phenothiazines has been described without external oxidants and hydrogen acceptors. The nitro of -nitrothiophenol works as both a hydrogen acceptor and a coupling group, and water is the only byproduct. The reaction involves the reduction of nitro groups, C-H bond thioetherification, and C-H bond dehydroaromatization. This scheme offers broad synthetic value for further elaborations, as exemplified by a 3-step total synthesis of antipsychotic chlorpromazine.
PubMed: 38773694
DOI: 10.1021/acs.joc.4c00039 -
Scientific Reports May 2024The present investigation explores the efficacy of green algae Ulva lactuca biochar-sulfur (GABS) modified with HSO and NaHCO in adsorbing methylene blue (MB) dye from...
The present investigation explores the efficacy of green algae Ulva lactuca biochar-sulfur (GABS) modified with HSO and NaHCO in adsorbing methylene blue (MB) dye from aqueous solutions. The impact of solution pH, contact duration, GABS dosage, and initial MB dye concentration on the adsorption process are all methodically investigated in this work. To obtain a thorough understanding of the adsorption dynamics, the study makes use of several kinetic models, including pseudo-first order and pseudo-second order models, in addition to isotherm models like Langmuir, Freundlich, Tempkin, and Dubinin-Radushkevich. The findings of the study reveal that the adsorption capacity at equilibrium (q) reaches 303.78 mg/g for a GABS dose of 0.5 g/L and an initial MB dye concentration of 200 mg/L. Notably, the Langmuir isotherm model consistently fits the experimental data across different GABS doses, suggesting homogeneous adsorption onto a monolayer surface. The potential of GABS as an efficient adsorbent for the extraction of MB dye from aqueous solutions is highlighted by this discovery. The study's use of kinetic and isotherm models provides a robust framework for understanding the intricacies of MB adsorption onto GABS. By elucidating the impact of various variables on the adsorption process, the research contributes valuable insights that can inform the design of efficient wastewater treatment solutions. The comprehensive analysis presented in this study serves as a solid foundation for further research and development in the field of adsorption-based water treatment technologies.
Topics: Methylene Blue; Charcoal; Ulva; Adsorption; Water Pollutants, Chemical; Kinetics; Water Purification; Sulfur; Hydrogen-Ion Concentration; Water; Edible Seaweeds
PubMed: 38773106
DOI: 10.1038/s41598-024-61868-9 -
Veterinary Anaesthesia and Analgesia 2024To compare changes in oesophageal (T-Oeso) and rectal (T-Rec) temperature in dogs during general anaesthesia and premedicated with fentanyl, medetomidine-fentanyl or...
OBJECTIVE
To compare changes in oesophageal (T-Oeso) and rectal (T-Rec) temperature in dogs during general anaesthesia and premedicated with fentanyl, medetomidine-fentanyl or acepromazine-fentanyl.
STUDY DESIGN
Prospective, randomized, blind clinical study.
ANIMALS
A total of 120 healthy dogs, aged 2-10 years and weighing 5-20 kg.
METHODS
Dogs were randomly allocated to one of three groups. Animals of F group were premedicated with fentanyl (0.01 mg kg), MF group with medetomidine (0.005 mg kg) and fentanyl (0.01 mg kg) and AF group with acepromazine (0.01 mg kg) and fentanyl (0.01 mg kg). Anaesthesia was induced with propofol and maintained with isoflurane in oxygen-air mixture. Fentanyl was administered continuously (0.01 mg kg hour). The T-Oeso, T-Rec and ambient temperatures were recorded after induction (T0) and subsequently at 10 minute intervals for 60 minutes (T10-T60). Data were analysed using anova or their non-parametric equivalents (p < 0.05).
RESULTS
Median T-Oeso was significantly higher in MF group between T0-T20 compared with other groups. Median T-Oeso significantly decreased in F group from 38.0 °C (T0) to 37.4 °C (T30), 37.1 °C (T40), 36.9 °C (T50) and 36.6 °C (T60), in MF group from 38.3 °C (T0) to 37.7 °C (T30), 37.5 °C (T40), 37.2 °C (T50) and 37.1 °C (T60) and in AF group from 37.7 °C (T0) to 37.3 °C (T40), 37.2 °C (T50) and 37.1 °C (T60). The T-Rec significantly decreased in F group from 38.0 °C (T0) to 37.4 °C (T40), 37.2 °C (T50) and 36.9 °C (T60), in MF group from 38.3 °C (T0) to 37.5 °C (T50) and 37.4 °C (T60) and in AF group from 38.2 °C (T0) to 37.6 °C (T40), 37.5 °C (T50) and 37.4 °C (T60).
CONCLUSIONS AND CLINICAL RELEVANCE
Premedication with fentanyl, medetomidine-fentanyl or acepromazine-fentanyl in the doses used decreased the T-Oeso and T-Rec. The T-Oeso at the beginning of anaesthesia was higher after premedication with medetomidine-fentanyl. However, this difference was not clinically significant.
Topics: Animals; Dogs; Fentanyl; Medetomidine; Acepromazine; Male; Female; Body Temperature; Esophagus; Rectum; Prospective Studies; Anesthesia, General; Anesthetics, Intravenous; Anesthetics, Combined; Preanesthetic Medication
PubMed: 38772852
DOI: 10.1016/j.vaa.2024.04.003 -
Lasers in Medical Science May 2024Tooth discoloration is a common concern in antimicrobial photodynamic therapy (aPDT) using various photosensitizers (PS). Toluidine Blue (TB), Methylene Blue (MB),...
BACKGROUND
Tooth discoloration is a common concern in antimicrobial photodynamic therapy (aPDT) using various photosensitizers (PS). Toluidine Blue (TB), Methylene Blue (MB), Phthalocyanine (Pc), and 2-mercaptopyridine-substituted zinc phthalocyanine (TM-ZnPc) are among those studied, but their relative impacts on tooth discoloration remain unclear.
AIM
This study aimed to compare the effects of TB, MB, Pc, and TM-ZnPc in aPDT on tooth discoloration, utilizing a controlled experimental setup.
MATERIALS AND METHODS
The study comprised seventy-five single-rooted incisors with root canals. Following meticulous preparation, a standardized area on the crown surface was designated for examination, and precise measurements of the initial tooth colors were recorded. Samples were randomly divided into five groups: Negative control, MB, TM, Pc, and TM-ZnPc. Photoactivation was performed using LED light, and color measurements were taken at multiple time points up to 90 days. Data were converted to Lab* color values of the CIE Lab* color system (International Commission on Illumination, Vienna, Austria), and ΔE values were calculated. Statistical analysis was performed using Two-way ANOVA and Post-Hoc Tukey tests (p < 0.05).
RESULTS
At day 7 and 30, TM-ZnPc and Pc caused less discoloration compared to MB and TB. TM-ZnPc caused more tooth discoloration compared to Pc (p < 0.05). Compared to baseline, MB and TM-ZnPc caused more tooth discoloration at 30 days and TB caused more tooth discoloration at 90 days (p < 0.05). No significant difference was observed in terms of tooth discoloration at all periods evaluated after Pc application (p > 0.05). All photosensitizers tested in the study caused tooth coloration.
CONCLUSION
All PS induced clinically detectable tooth discoloration, with TB and MB causing more significant discoloration compared to Pc and TM-ZnPc at certain time points. TM-ZnPc and Pc demonstrated more stable coloration levels over time, suggesting their potential reliability in aPDT applications. This study highlights the importance of selecting appropriate PS to minimize tooth discoloration in aPDT, with Pc showing promise in this regard.
Topics: Photochemotherapy; Photosensitizing Agents; Humans; Tooth Discoloration; Tolonium Chloride; Methylene Blue; Spectrophotometry; Isoindoles; Zinc Compounds; Indoles; Organometallic Compounds
PubMed: 38771549
DOI: 10.1007/s10103-024-04085-0 -
The Journal of Physical Chemistry. A May 2024We have designed, synthesized, and characterized a donor-acceptor triad, , that consists of a π-interacting phenothiazine-linked porphyrin as a donor and sensitizer and...
We have designed, synthesized, and characterized a donor-acceptor triad, , that consists of a π-interacting phenothiazine-linked porphyrin as a donor and sensitizer and fullerene as an acceptor to seek charge separation upon photoexcitation. The optical absorption spectrum revealed red-shifted Soret and Q-bands of porphyrin due to charge transfer-type interactions involving the two ethynyl bridges carrying electron-rich and electron-poor substituents. The redox properties suggested that the phenothiazine-porphyrin part of the molecule is easier to oxidize and the fullerene part is easier to reduce. DFT calculations supported the redox properties wherein the electron density of the highest molecular orbital (HOMO) was distributed over the donor phenothiazine-porphyrin entity while the lowest unoccupied molecular orbital (LUMO) was distributed over the fullerene acceptor. TD-DFT studies suggested the involvement of both the S and S states in the charge transfer process. The steady-state emission spectrum, when excited either at porphyrin Soret or visible band absorption maxima, revealed quenched emission both in nonpolar and polar solvents, suggesting the occurrence of excited state events. Finally, femtosecond transient absorption spectral studies were performed to witness the charge separation by utilizing solvents of different polarities. The transient data was further analyzed by GloTarAn by fitting the data with appropriate models to describe photochemical events. From this, the average lifetime of the charge-separated state calculated was found to be 169 ps in benzonitrile, 319 ps in dichlorobenzene, 1.7 ns in toluene for Soret band excitation, and ∼320 ps for Q-band excitation in benzonitrile.
PubMed: 38758579
DOI: 10.1021/acs.jpca.4c00976 -
Central Nervous System Agents in... May 2024Alzheimer's disease is a neurodegenerative disorder that affects learning, memory and behavioral turbulence in elderly patients. Acetylcholinesterase (AChE) inhibitors...
BACKGROUND
Alzheimer's disease is a neurodegenerative disorder that affects learning, memory and behavioral turbulence in elderly patients. Acetylcholinesterase (AChE) inhibitors act as anti-Alzheimer's agents. Phenothiazine derivatives are considered momentous anti-Alzheimer's agents because of their AChE inhibitory activity. The elevated levels and increased expression of this protein have been associated with Alzheimer's disease. Coumarin-fused phenothiazines have emerged as significant anti-Alzheimer's agents due to their notable receptor inhibitory activity.
OBJECTIVE
Some unique phenothiazine analogs were designed, and computational studies were conducted to explore their inhibitory activity against the AChE enzyme (PDB id: 4EY7) by using the Schrodinger suite-2019-4.
METHODS
Docking studies were conducted by using the Glide module; binding free energies were calculated by means of the Prime MM-GBSA module, and Molecular dynamics (MD) simulation was performed by using the Desmond module of the Schrodinger suite. Glide scores were used to find out the binding affinity of the ligands with the target 4EY7.
RESULTS
The compounds exhibited enhanced hydrophobic interactions and formed hydrogen bonds, effectively impeding Acetylcholinesterase. The Glide scores for the compounds ranged from -13.4237 to -8.43439, surpassing the standard (Donepezil) with a score of -16.9898. Interestingly, a positive value was obtained for the MM-GBSA binding of the potent inhibitor. To gain insights into the dynamic behavior of the protein A8, molecular dynamics (MD) simulations were employed.
CONCLUSION
Based on the results, the study concludes that phenothiazine derivatives show promise as acetylcholinesterase inhibitors. Compounds with notable Glide scores are poised to exhibit significant anti-Alzheimer's activity, suggesting their potential therapeutic efficacy. Further in vitro and in vivo investigations are warranted to validate and explore the therapeutic potentials of these compounds.
PubMed: 38757327
DOI: 10.2174/0118715249300784240430110628 -
Chemistry, An Asian Journal May 2024In this study, we have successfully designed and synthesized two novel dual-emission emitters featuring phenothiazine-5-oxide and phenothiazine-5,5-dioxide motifs,...
In this study, we have successfully designed and synthesized two novel dual-emission emitters featuring phenothiazine-5-oxide and phenothiazine-5,5-dioxide motifs, characterized by highly lopsided and asymmetric conformational states. Through rigorous spectral examinations and DFT calculations, the compounds exhibit distinctive ICT phenomena, coupled with efficient emission in solid states and AIEE characteristics under high water fractions in DMF/H2O mixtures. These non-planar luminogens exhibit vibrant green and blue solid-state luminescence, with fluorescence quantum yields of 24.1% and 15.21%, respectively. Additionally, they both emit green fluorescence in THF solution, with notable emission quantum yields 36.4% and 30.4%. Comprehensive theoretical investigations unveil well-defined electron cloud density separation between the energies of HOMO/LUMO levels within the two luminogens. Notably, the targeted molecule harboring the phenothiazine-S,S-dioxide motif also demonstrates remarkable reversible mechanofluorochromic properties. Moreover, we testify their potential in applications such as solid-state rewritable information storage and live-cell imaging in solution states. Through theoretical calculations and comparative studies, we have explored the intrinsic relationship between molecular structure and performance, effectively screening and identifying new fluorescent molecules exhibiting outstanding luminescent attributes. These discoveries establish robust theoretical and technical foundation for the synthesis and application of efficient DSE-based MFC materials, opening new avenues in the realm of advanced luminescent materials.
PubMed: 38751300
DOI: 10.1002/asia.202400195 -
Talanta Aug 2024Herein, we fabricated an electrochemical (EC) and UV-visible absorption (UV-vis) dual mode split-type immunoassay for the detection of 17β-estradiol (E2), which was...
Herein, we fabricated an electrochemical (EC) and UV-visible absorption (UV-vis) dual mode split-type immunoassay for the detection of 17β-estradiol (E2), which was mediated by liposome encapsulated methylene blue (MB@lip). MB molecule acted as the probe in the EC and UV-vis absorption dual mode detections, and its release was controlled by liposome. The competitive immune recognition was conducted between the E2 in the sample and E2 conjugated bovine serum protein (E2-BSA) adsorbed on the 96-wells plate in combining with E2 antibody labeled with MB@lip (E2-Ab/MB@lip). MB molecule could be released from the resulting immune composite of E2-BSA/E2-Ab/MB@lip in the presence of Triton X-100, and quantified by UV-vis and EC methods. The three-dimensional cross-linked reduced graphene oxide/TiC (3D-rGO/TiC) aerogel was prepared through hydrothermal method, then complexed with the electroactive anthraquinone (AQ) and used as the electrode modified material. The AQ/3D-rGO/TiC composite had high surface area and provided abundant adsorption sites for MB, and the displacement/competitive behavior between AQ and MB could dexterously achieve the ratiometric EC detection of E2. In addition, the inherent blue color of MB allowed it to be analyzed by UV-vis absorption method. The proposed dual mode detection method exhibited broad linear ranges of 0.1 pg mL to 50 ng mL (by UV-vis) and 0.03 pg mL to 50 ng mL (by EC) for E2 detection, and the detection limits were 0.023 pg mL (S/N = 3) and 8.0 fg mL (S/N = 3), respectively. Moreover, the proposed immunoassay exhibited good practicability and was applied to monitor E2 in milk and serum successfully.
Topics: Methylene Blue; Estradiol; Liposomes; Electrochemical Techniques; Immunoassay; Animals; Spectrophotometry, Ultraviolet; Cattle; Limit of Detection; Serum Albumin, Bovine
PubMed: 38749160
DOI: 10.1016/j.talanta.2024.126243 -
The Journal of Physical Chemistry. A May 2024Organic fluorescent molecules have received considerable attention owing to their various optoelectronic applications. Herein, we report the design and synthesis of two...
Organic fluorescent molecules have received considerable attention owing to their various optoelectronic applications. Herein, we report the design and synthesis of two cholesterol-functionalized cyanostyrene-phenothiazine-based D-π-A systems that are emissive in both the solution and solid states. The newly synthesized cholesterol-appended phenothiazine-cyanostyrene diads and vary in the -alkylation of phenothiazine, respectively, with─ and─ chains. Both molecules are highly fluorescent and show reasonably good quantum yields in nonpolar solvents because of twisted intramolecular charge transfer (TICT). The molecules exhibit aggregation-induced emission in the solid state. Due to the presence of flexible alkyl chains in the phenothiazine and cholesterol moieties, and show mechanochromic luminescence switching in response to external shear stress and emission recovery under methanol vapor. Powder X-ray diffraction studies prove that the emission switching on the applied stimuli in both and is attributed to the reversible transformation between the crystalline and amorphous states. Time-dependent density functional theory (TD-DFT) studies are carried out to gain insight into the ICT interactions. TD-DFT analysis at the TD-M06-2X/def2-TZVP level further revealed that in both molecules, the lowest unoccupied molecular orbital (LUMO) + 2, LUMO, highest occupied molecular orbital (HOMO), and HOMO - 1 orbitals are responsible for the charge transfer interactions. These ICT interactions are identified as π-π* type interactions.
PubMed: 38742635
DOI: 10.1021/acs.jpca.4c00373 -
Photodiagnosis and Photodynamic Therapy Jun 2024Efflux pumps are active transporters, which allow the cell to remove toxic substances from within the cell including antibiotics and photosensitizer complexes. Efflux...
Efflux pumps are active transporters, which allow the cell to remove toxic substances from within the cell including antibiotics and photosensitizer complexes. Efflux pump inhibitors (EPIs), chemicals that prevent the passage of molecules through efflux pumps, play a crucial role in antimicrobial effectiveness against pathogen. In this work, we studied the effect of EPI, namely, reserpine, on photodeactivation rate of pathogens when used with Ag NPs and methylene blue (MB). Our results show that using reserpine led to a higher deactivation rate than Ag NPs and MB alone. The mechanism of this observation was investigated with singlet oxygen generation amount. Additionally, different sizes of Ag NPs were tested with reserpine. Molecular docking calculation shows that reserpine had higher affinity toward AcrB than MB. The improvement in bacterial deactivation rate is attributed to blockage of the AcrAB-TolC efflux pump preventing the removal of MB rather than enhanced singlet oxygen production. These results suggest that using reserpine with nanoparticles and photosynthesize is a promising approach in photodynamic therapy.
Topics: Photochemotherapy; Photosensitizing Agents; Methylene Blue; Silver; Reserpine; Metal Nanoparticles; Singlet Oxygen; Molecular Docking Simulation; Escherichia coli
PubMed: 38740317
DOI: 10.1016/j.pdpdt.2024.104212