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ChemistryOpen Oct 2022The generation of the quaternary stereocenter at the C9 position of salvinorin A precursors by the Claisen rearrangement was investigated. The required allyl alcohol was...
The generation of the quaternary stereocenter at the C9 position of salvinorin A precursors by the Claisen rearrangement was investigated. The required allyl alcohol was prepared from a Wieland-Miescher ketone using a known γ-hydroxylation, reduction of the enone double bond, cyanohydrin formation, and elimination, yielding an unsaturated nitrile. A two-step reduction led to the required allyl alcohol. The subsequent Johnson-Claisen rearrangement provided a mixture of two diastereomeric 1,4-unsaturated esters in a ratio of around 2.6 : 1. The major isomer could be converted to a key intermediate of the Hagiwara synthesis of salvinorin A.
Topics: Diterpenes, Clerodane; Esters; Ketones; Nitriles; Propanols; Stereoisomerism
PubMed: 35218166
DOI: 10.1002/open.202200015 -
Journal of the American Chemical Society Sep 2023This study reports the successful development of a sustainable synthesis protocol for a phase-pure metal azolate framework (MAF-6) and its application in enzyme...
This study reports the successful development of a sustainable synthesis protocol for a phase-pure metal azolate framework (MAF-6) and its application in enzyme immobilization. An esterase@MAF-6 biocomposite was synthesized, and its catalytic performance was compared with that of esterase@ZIF-8 and esterase@ZIF-90 in transesterification reactions. Esterase@MAF-6, with its large pore aperture, showed superior enzymatic performance compared to esterase@ZIF-8 and esterase@ZIF-90 in catalyzing transesterification reactions using both -propanol and benzyl alcohol as reactants. The hydrophobic nature of the MAF-6 platform was shown to activate the immobilized esterase into its open-lid conformation, which exhibited a 1.5- and 4-times enzymatic activity as compared to free esterase in catalyzing transesterification reaction using -propanol and benzyl alcohol, respectively. The present work offers insights into the potential of MAF-6 as a promising matrix for enzyme immobilization and highlights the need to explore MOF matrices with expanded pore apertures to broaden their practical applications in biocatalysis.
Topics: 1-Propanol; Carboxylesterase; Esterases; Benzyl Alcohol
PubMed: 37671920
DOI: 10.1021/jacs.3c05488 -
Journal of Visualized Experiments : JoVE Jun 2022The nematode Caenorhabditis elegans is an attractive model organism to study learning and memory at molecular and cellular levels because of the simplicity of its...
The nematode Caenorhabditis elegans is an attractive model organism to study learning and memory at molecular and cellular levels because of the simplicity of its nervous system, whose chemical and electrical wiring diagrams were completely reconstructed from serial electron micrographs of thin sections. Here, we describe detailed protocols for the conditioning of C. elegans by massed and spaced training for the formation of short-term memory (STM) and long-term memory (LTM), respectively. By pairing 1-propanol and hydrochloric acid as conditioned and unconditioned stimuli, respectively, C. elegans was successfully trained to form aversive associative STM and LTM. While naïve animals were attracted to 1-propanol, the trained animals were no longer or very weakly attracted to 1-propanol. Like in other organisms such as Aplysia and Drosophila, "learning and memory genes" play essential roles in memory formation. Particularly, NMDA-type glutamate receptors, expressed in only six pairs of interneurons in C. elegans, are required for the formation of both STM and LTM, possibly as a coincidence factor. Therefore, the memory trace may reside among the interneurons.
Topics: 1-Propanol; Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Conditioning, Classical; Memory, Long-Term; Memory, Short-Term; Receptors, N-Methyl-D-Aspartate
PubMed: 35816003
DOI: 10.3791/64137 -
Annals of Work Exposures and Health Oct 2022Although containment testing of fume cupboards (FC) according to the standards EN 14175-3 (2019) or ANSI/ASHRAE 110 (2016) is well established for type testing, its...
Although containment testing of fume cupboards (FC) according to the standards EN 14175-3 (2019) or ANSI/ASHRAE 110 (2016) is well established for type testing, its application is currently much less accepted and practised for evaluating containment on-site. Few of the several million FC in the market have been tested at installation and commissioning, and even less undergo verification of containment during their service life in the laboratories. Several reasons have led to this unsafe situation. To address this challenge, a new concept has been developed to allow for rapid on-site testing of FC to gain knowledge as to the functional efficiency as well as to safety aspects for the operator. The concept consists of a movable robot-aided test equipment that can be installed quickly to the FC in running labs. Multiple sensors detect the tracer gas isopropanol. Within a test run of only 10-min data is collected to quantify containment at the sash opening and to determine purge efficiency. The method reveals impact from interfering effects such as draughts, air distribution, and movements and from equipment installed, and is a tool for the optimization of operating conditions of a lab. This article presents an advanced alternative to the existing containment tests, particularly for on-site testing. The method assesses not only proper operation of the FC in its environment, but also the suitability of a FC for a given use under aspects of health and safety evaluation.
Topics: 2-Propanol; Air Movements; Equipment Design; Gases; Humans; Occupational Exposure; Robotics; Ventilation
PubMed: 35716067
DOI: 10.1093/annweh/wxac043 -
Journal of Hazardous Materials Feb 2023The recalcitrant β-blockers have been widely detected in aquatic environments up to several hundred μg/L, which are major contributors to β1 antagonistic activities...
The recalcitrant β-blockers have been widely detected in aquatic environments up to several hundred μg/L, which are major contributors to β1 antagonistic activities in wastewater. Their biodegradation mechanisms remain obscure, hindering the development of efficient removal techniques. This study constructed the biodegradation pathways for three typical β-blockers, namely atenolol, metoprolol, and propranolol, assessed the toxicity of their major biotransformation products, and identified the key enzyme catalyzing the O-dealkylation reaction leading to pollutant mineralization. Atenolol and metoprolol degradation was more efficient than that of propranolol by activated sludge, producing metoprolol acid (MTPA) as a major intermediate. Hydrogenophaga sp. YM1 isolated from activated sludge possess the α-ketoglutarate dependent dioxygenase (TfdA) responsible for O-dealkylation of MTPA and propranolol, producing 4-hydroxyphenylacetic acid (4-HPA) that can be further degraded and ultimately enters the TCA cycle. The role of TfdA was verified by proteomics, enzyme stimulation/inhibition tests, and gene knockout experiments. Molecular docking suggests its different interactions with MTPA and propranolol. Acetate facilitated the degradation of β-blockers efficiently. The results may shed light on enhanced biological removals of broader β-blockers and their transformation products in the environment.
Topics: Wastewater; Propranolol; Metoprolol; Sewage; Atenolol; Molecular Docking Simulation; Adrenergic beta-Antagonists
PubMed: 36417780
DOI: 10.1016/j.jhazmat.2022.130338 -
Molecules (Basel, Switzerland) Mar 2020Biological systems usually respond differently to enantiomers of a chiral molecule due to the inherent chirality of the active receptor sites of enzymes in nature [...].
Biological systems usually respond differently to enantiomers of a chiral molecule due to the inherent chirality of the active receptor sites of enzymes in nature [...].
Topics: Azepines; Benzyl Alcohols; Butyrates; Catalysis; Chemistry Techniques, Synthetic; Epoxy Compounds; Humans; Hydrocarbons, Fluorinated; Propanols; Ruthenium Compounds; Schiff Bases; Stereoisomerism
PubMed: 32168826
DOI: 10.3390/molecules25061266 -
International Journal of Legal Medicine Nov 2020Accurate determination of a person's blood alcohol concentration (BAC) is an important task in forensic toxicology laboratories because of the existence of statutory... (Review)
Review
Accurate determination of a person's blood alcohol concentration (BAC) is an important task in forensic toxicology laboratories because of the existence of statutory limits for driving a motor vehicle and workplace alcohol testing regulations. However, making a correct interpretation of the BAC determined in postmortem (PM) specimens is complicated, owing to the possibility that ethanol was produced in the body after death by the action of various micro-organisms (e.g., Candida species) and fermentation processes. This article reviews various ways to establish the source of ethanol in PM blood, including collection and analysis of alternative specimens (e.g., bile, vitreous humor (VH), and bladder urine), the identification of non-oxidative metabolites of ethanol, ethyl glucuronide (EtG) and ethyl sulfate (EtS), the urinary metabolites of serotonin (5-HTOL/5-HIAA), and identification of n-propanol and n-butanol in blood, which are known putrefaction products. Practical utility of the various biomarkers including specificity and stability is discussed.
Topics: 1-Butanol; 1-Propanol; Autopsy; Blood Alcohol Content; Ethanol; Flame Ionization; Forensic Toxicology; Gas Chromatography-Mass Spectrometry; Glucuronates; Serotonin; Specimen Handling; Sulfuric Acid Esters
PubMed: 32940841
DOI: 10.1007/s00414-020-02415-9 -
Antimicrobial Resistance and Infection... Nov 2022Reports are available on cross-resistance between antibiotics and biocides. We evaluated the effect of povidone-iodine (PVP-I) and propanol-based mecetronium ethyl...
BACKGROUND
Reports are available on cross-resistance between antibiotics and biocides. We evaluated the effect of povidone-iodine (PVP-I) and propanol-based mecetronium ethyl sulphate (PBM) on resistance development, antibiotics cross-resistance, and virulence in Staphylococcus aureus.
METHODS
The minimum inhibitory concentration (MIC) of PVP-I and PBM were determined against S. aureus ATCC 25923 using the agar-dilution method. Staphylococcus aureus ATCC 25923 was subjected to subinhibitory concentrations of the tested biocides in ten consecutive passages followed by five passages in a biocide-free medium; MIC was determined after each passage and after the fifth passage in the biocide-free medium. The developed resistant mutant was tested for cross-resistance to different antibiotics using Kirby-Bauer disk diffusion method. Antibiotic susceptibility profiles as well as biocides' MIC were determined for 97 clinical S. aureus isolates. Isolates were categorized into susceptible and resistant to the tested biocides based on MIC distribution pattern. The virulence of the biocide-resistant mutant and the effect of subinhibitory concentrations of biocides on virulence (biofilm formation, hemolysin activity, and expression of virulence-related genes) were tested.
RESULTS
PVP-I and PBM MIC were 5000 μg/mL and 664 μg/mL. No resistance developed to PVP-I but a 128-fold increase in PBM MIC was recorded, by repeated exposure. The developed PBM-resistant mutant acquired resistance to penicillin, cefoxitin, and ciprofloxacin. No clinical isolates were PVP-I-resistant while 48.5% were PBM-resistant. PBM-resistant isolates were more significantly detected among multidrug-resistant isolates. PVP-I subinhibitory concentrations (¼ and ½ of MIC) completely inhibited biofilm formation and significantly reduced hemolysin activity (7% and 0.28%, respectively). However, subinhibitory concentrations of PBM caused moderate reduction in biofilm activity and non-significant reduction in hemolysin activity. The ½ MIC of PVP-I significantly reduced the expression of hla, ebps, eno, fib, icaA, and icaD genes. The virulence of the biocide-resistant mutant was similar to that of parent strain.
CONCLUSION
PVP-I is a highly recommended antiseptic for use in healthcare settings to control the evolution of high-risk clones. Exposure to PVP-I causes no resistance-development risk in S. aureus, with virulence inhibition by subinhibitory concentrations. Also, special protocols need to be followed during PBM use in hospitals to avoid the selection of resistant strains.
Topics: Humans; Staphylococcus aureus; Povidone-Iodine; Anti-Bacterial Agents; Virulence; 1-Propanol; Hemolysin Proteins; Drug Resistance, Bacterial; Staphylococcal Infections; Disinfectants
PubMed: 36369050
DOI: 10.1186/s13756-022-01178-9 -
Current Drug Targets 2021Natural products, such as phenylpropanoids, which are found in essential oils derived from aromatic plants, have been explored during non-clinical psychopharmacology... (Review)
Review
BACKGROUND
Natural products, such as phenylpropanoids, which are found in essential oils derived from aromatic plants, have been explored during non-clinical psychopharmacology studies, to discover new molecules with relevant pharmacological activities in the central nervous system, especially antidepressant and anxiolytic activities. Major depressive disorder is a highly debilitating psychiatric disorder and is considered to be a disabling public health problem, worldwide, as a primary factor associated with suicide. Current clinically administered antidepressants have late-onset therapeutic actions, are associated with several side effects, and clinical studies have reported that some patients do not respond well to treatment or reach complete remission.
OBJECTIVE
To review important new targets for antidepressant activity and to select phenylpropanoids with antidepressant activity, using Molegro Virtual Docker and Ossis Data Warris, and to verify substances with more promising antidepressant activity.
RESULTS AND CONCLUSION
An in silico molecular modeling study, based on homology, was conducted to determine the three-dimensional structure of the 5-hydroxytryptamine 2A receptor (5- HT2AR), then molecular docking studies were performed and the predisposition for cytotoxicity risk among identified molecules was examined. A model for 5-HT2AR homology, with satisfactory results, was obtained indicating the good stereochemical quality of the model. The phenylpropanoid 4-allyl-2,6-dimethoxyphenol showed the lowest binding energy for 5-HT2AR, with results relevant to the L-arginine/nitric oxide (NO)/cGMP pathway, and showed no toxicity within the parameters of mutagenicity, carcinogenicity, reproductive system toxicity, and skin-tissue irritability, when evaluated in silico; therefore, this molecule can be considered promising for the investigation of antidepressant activity.
Topics: Antidepressive Agents; Depressive Disorder, Major; Eugenol; Humans; Molecular Docking Simulation; Propanols; Serotonin 5-HT2 Receptor Antagonists
PubMed: 32881667
DOI: 10.2174/1389450121666200902171838 -
Zhongguo Zhong Yao Za Zhi = Zhongguo... Jun 2022The present study investigated the chemical constituents from the dry seeds of Hydnocarpus anthelminthica. The compounds were isolated and purified from the dry seeds of...
The present study investigated the chemical constituents from the dry seeds of Hydnocarpus anthelminthica. The compounds were isolated and purified from the dry seeds of H. anthelminthica by various chromatographic techniques including column chromatography over silica gel and Sephadex LH-20 and reversed-phase HPLC. Their structures were identified by spectroscopic analysis. The in vitro cytotoxic activities were determined by MTT assay. Ten compounds were isolated and identified as 2-(4-hydroxy-3,5-dimethoxyphenyl)-3-(2-hydroxy-5-methoxyphenyl)-3-oxo-1-propanol(1), threo-1,2-bis-(4-hydroxy-3-methoxyphenyl)-propane-1,3-diol(2), erythro-1,2-bis-(4-hydroxy-3-methoxyphenyl)-propane-1,3-diol(3), 2-(4-hydroxy-3-methoxyphenyl)-3-(2-hydroxy-5-methoxyphenyl)-3-oxo-1-propanol(4), 3-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one(5), chrysoeriol(6), evofolin B(7), apigenin-3'-methoxy-7-O-rutinoside(8), luteolin(9), and vitexin(10). Compound 1 is a new compound. Compounds 4 and 5 were isolated from this genus for the first time. All compounds showed no significant cytotoxic activity.
Topics: 1-Propanol; Propane; Seeds
PubMed: 35718521
DOI: 10.19540/j.cnki.cjcmm.20220412.201