ChemInform Abstract: Substituted Monocarbon Carboranes Involving Thiol, Disulfide or Dimethyl Sulfide Ligands.

The complex (Me2S)Cl3W(μ-SPh)2WCl3(SMe2), 1, has been isolated as one product of the 1:1 reaction between WCl4(Me2S)2 and SiMe3(SPh) in CH2Cl2 solution. A single crystal X-ray diffraction study shows that the molecule has the relatively unusual edge-shared bioctahedral structure, with a W—W bond length of 2.759(1) Å. The dimethyl sulfide ligands occupy positions trans to one another in the equatorial mean plane of the molecule, which has two-fold symmetry imposed on it. The structure was solved by the heavy atom method and refined to R = 0.044 and Rw = 0.058 for 2001 reflections. Crystals of 1 are monoclinic, space group C2/c, with a = 17.445(4), b = 12.594(2), c = 11.509(3) Å, β = 91.22(1)°, and Z = 4.

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Reactions of confacial bioctahedral ditungsten(III) species: Product distribution in reactions of the μ-hydrido-(bis-μ-dimethylsulfide)bis (trichlorotungstate(III)) ion, and trichlorotungsten(III)(μ-hydrido)bis((μ-dimethylsulfide)(dimethylsulfide)-dichlorotungsten(III) with benzyl bromide and bromide ion

Canadian Journal of Chemistry ◽

10.1139/v90-105 ◽

1990 ◽

Vol 68 (5) ◽

pp. 685-690 ◽

Cited By ~ 1

Author(s):

Joanne M. Ball ◽

P. Michael Boorman ◽

Kelly J. Moynihan

Keyword(s):

Nmr Spectra ◽

Dimethyl Sulfide ◽

Benzyl Bromide ◽

Product Distribution ◽

Methyl Groups ◽

H Nmr ◽

Sulfide Ligands ◽

Bromide Ion

Reactions of compound Cl3W(μ-H)(μ-Me2S)2WCl2(Me2S), 1, and salts of derived chloro anion [Cl3W(μ-H)(μ-Me2S)2WCl3]−, 2, with bromide ion and with benzyl bromide are described. 1 was previously shown (1) to exist as a mixture of meso (C2v) and DL-pair (C1) of isomers, with the C2v isomer being the more stable. Displacement of the terminal dimethyl sulfide ligand of 1 by bromide ion results in the formation of the analogous isomers of ion [Cl3W(μ-H)(μ-Me2S)2WCl2Br]−, with retention of stereochemistry. The 1H NMR spectra of compounds in this series are uniquely informative as to the isomers present since the two environments of the methyl groups in the bridging dimethyl sulfide ligands (axial and equatorial) provide a probe for the ion stereochemistry. This is used to show that in reactions of 2 with benzyl bromide, after replacement of μ-H by Br, Br exchanges with terminal chlorides to give a mixture of isomers. Reactions of 1 with benzyl bromide are further complicated by the fact that both terminal dimethyl sulfide and μ-H are replaced by bromides which then redistribute over all possible terminal sites. Keywords: hydride, confacial bioctahedral complexes, tungsten, bromocarbons.

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Substituted monocarbon carboranes involving thiol, disulfide or dimethyl sulfide ligands

Journal of the Chemical Society Dalton Transactions ◽

10.1039/dt9920000119 ◽

1992 ◽

pp. 119 ◽

Cited By ~ 20

Author(s):

Shah-Alam Khan ◽

John H. Morris ◽

Mary Harman ◽

Michael B. Hursthouse

Keyword(s):

Dimethyl Sulfide ◽

Sulfide Ligands

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Microbial Origins and Consequences of Dimethyl Sulfide

Microbe Magazine ◽

10.1128/microbe.7.181.1 ◽

2012 ◽

Vol 7 (4) ◽

pp. 181-185 ◽

Cited By ~ 2

Author(s):

Andrew W. B. Johnston ◽

Andrew R. J. Curson ◽

Jonathan D. Todd

Keyword(s):

Dimethyl Sulfide

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Identification of VOCs in essential oils extracted using ultrasound- and microwave-assisted methods from sweet cherry flower

Scientific Reports ◽

10.1038/s41598-020-80891-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Huimin Zhang ◽

Hongguang Yan ◽

Quan Li ◽

Hui Lin ◽

Xiaopeng Wen

Keyword(s):

Essential Oil ◽

Sweet Cherry ◽

Dimethyl Sulfide ◽

Solid Phase ◽

Oil Yield ◽

Gas Chromatography Mass Spectrometry ◽

Process Conditions ◽

Important Indicator ◽

Microwave Assisted ◽

Essential Oil Yield

AbstractThe floral fragrance of plants is an important indicator in their evaluation. The aroma of sweet cherry flowers is mainly derived from their essential oil. In this study, based on the results of a single-factor experiment, a Box–Behnken design was adopted for ultrasound- and microwave-assisted extraction of essential oil from sweet cherry flowers of the Brooks cultivar. With the objective of extracting the maximum essential oil yield (w/w), the optimal extraction process conditions were a liquid–solid ratio of 52 mL g−1, an extraction time of 27 min, and a microwave power of 435 W. The essential oil yield was 1.23%, which was close to the theoretical prediction. The volatile organic compounds (VOCs) of the sweet cherry flowers of four cultivars (Brooks, Black Pearl, Tieton and Summit) were identified via headspace solid phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). The results showed that a total of 155 VOCs were identified and classified in the essential oil from sweet cherry flowers of four cultivars, 65 of which were shared among the cultivars. The highest contents of VOCs were aldehydes, alcohols, ketones and esters. Ethanol, linalool, lilac alcohol, acetaldehyde, (E)-2-hexenal, benzaldehyde and dimethyl sulfide were the major volatiles, which were mainly responsible for the characteristic aroma of sweet cherry flowers. It was concluded that the VOCs of sweet cherry flowers were qualitatively similar; however, relative content differences were observed in the four cultivars. This study provides a theoretical basis for the metabolism and regulation of the VOCs of sweet cherry flowers.

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The Influence of Ocean Acidification and Warming on DMSP & DMS in New Zealand Coastal Water

Atmosphere ◽

10.3390/atmos12020181 ◽

2021 ◽

Vol 12 (2) ◽

pp. 181

Author(s):

Alexia D. Saint-Macary ◽

Neill Barr ◽

Evelyn Armstrong ◽

Karl Safi ◽

Andrew Marriner ◽

...

Keyword(s):

Ocean Acidification ◽

Coastal Water ◽

Phytoplankton Community ◽

Dimethyl Sulfide ◽

Temperature Treatment ◽

Low Ph ◽

Trace Gas ◽

Mesocosm Experiments ◽

Future Warming ◽

Higher Temperature

The cycling of the trace gas dimethyl sulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) may be affected by future ocean acidification and warming. DMSP and DMS concentrations were monitored over 20-days in four mesocosm experiments in which the temperature and pH of coastal water were manipulated to projected values for the year 2100 and 2150. This had no effect on DMSP in the two-initial nutrient-depleted experiments; however, in the two nutrient-amended experiments, warmer temperature combined with lower pH had a more significant effect on DMSP & DMS concentrations than lower pH alone. Overall, this indicates that future warming may have greater influence on DMS production than ocean acidification. The observed reduction in DMSP at warmer temperatures was associated with changes in phytoplankton community and in particular with small flagellate biomass. A small decrease in DMS concentration was measured in the treatments relative to other studies, from −2% in the nutrient-amended low pH treatment to −16% in the year 2150 pH and temperature conditions. Temporal variation was also observed with DMS concentration increasing earlier in the higher temperature treatment. Nutrient availability and community composition should be considered in models of future DMS.

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Dynamical study of infochemical influences on tropic interaction of diffusive plankton system

SN Applied Sciences ◽

10.1007/s42452-021-04237-9 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Satish Kumar Tiwari ◽

Ravikant Singh ◽

Nilesh Kumar Thakur

Keyword(s):

Dimethyl Sulfide ◽

Algal Bloom ◽

Turing Instability ◽

Model System ◽

Ode Model ◽

Estuarine Ecosystem ◽

Dynamical Study ◽

Oscillatory Dynamics ◽

The Stability ◽

Microzooplankton Grazing

AbstractWe propose a model for tropic interaction among the infochemical-producing phytoplankton and non-info chemical-producing phytoplankton and microzooplankton. Volatile information-conveying chemicals (infochemicals) released by phytoplankton play an important role in the food webs of marine ecosystems. Microzooplankton is an ecologically important grazer of phytoplankton for coexistence of a large number of phytoplankton species. Here, we discuss how information transferred by dimethyl sulfide shapes the interaction of phytoplankton. Phytoplankton deterrents may lead to propagation of IPP bloom. The interaction between IPP and microzooplankton follows the Beddington–DeAngelis-type functional response. Analytically, we discuss boundedness, stability and Turing instability of the model system. We perform numerical simulation for temporal (ODE model) as well as a spatial model system. Our numerical investigation shows that microzooplankton grazing refuse of IPP leads to oscillatory dynamics. Increasing diffusion coefficient of microzooplankton shows Turing instability. Time evolution also plays an important role in the stability of system dynamics. The results obtained in this paper are useful to understand the dominance of algal bloom in coastal and estuarine ecosystem.

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In-Vitro Evaluation of the Antioxidant and Anti-Inflammatory Activity of Volatile Compounds and Minerals in Five Different Onion Varieties

Separations ◽

10.3390/separations8050057 ◽

2021 ◽

Vol 8 (5) ◽

pp. 57

Author(s):

Rokayya Sami ◽

Abeer Elhakem ◽

Mona Alharbi ◽

Manal Almatrafi ◽

Nada Benajiba ◽

...

Keyword(s):

Volatile Compounds ◽

Dimethyl Sulfide ◽

Antioxidant Activities ◽

Dry Weight ◽

No Production ◽

Oxidative Stresses ◽

Anti Inflammatory ◽

Red Variety ◽

A Minor

Onions contain high antioxidants compounds that fight inflammation against many diseases. The purpose was to investigate some selected bioactive activities of onion varieties (Yellow, Red, Green, Leek, and Baby). Antioxidant assays and anti-inflammatory activities such as NO production with the addition of some bioactive components were determined and analyzed by using a spectrophotometer. Gas chromatography and mass spectrometry (GC–MS) was used for the volatile compounds, while an Atomic absorption spectrometer was used for mineral determinations. Red variety achieved the highest antioxidant activities. The total flavonoids were between (12.56 and 353.53 mg Quercetin/gin dry weight) (dw) and the total phenol was (8.75–25.73 mg/g dw). Leek, Yellow and Green extracts achieved highly anti-inflammatory values (3.71–4.01 μg/mL) followed by Red and Baby extracts, respectively. The highest contents of sodium, potassium, zinc, and calcium were established for Red onions. Furfuraldehyde, 5-Methyl-2-furfuraldehyde, 2-Methyl-2-pentenal, and 1-Propanethiol were the most predominant, followed by a minor abundance of the other compounds such as Dimethyl sulfide, Methyl allyl disulfide, Methyl-trans-propenyl-disulfide, and Methyl propyl disulfide. The results recommend that these varieties could act as sources of essential antioxidants and anti-inflammatories to decrease inflammation and oxidative stresses, especially red onions that recorded high activities.

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Promotional Effects of Rare-Earth Praseodymium (Pr) Modification over MCM-41 for Methyl Mercaptan Catalytic Decomposition

Processes ◽

10.3390/pr9020400 ◽

2021 ◽

Vol 9 (2) ◽

pp. 400

Author(s):

Xiaohua Cao ◽

Jichang Lu ◽

Yutong Zhao ◽

Rui Tian ◽

Wenjun Zhang ◽

...

Keyword(s):

Dimethyl Sulfide ◽

Catalytic Decomposition ◽

Product Distribution ◽

Acid Sites ◽

Methyl Mercaptan ◽

Praseodymium Oxide ◽

X Ray ◽

Xps Characterization ◽

Temperature Programmed ◽

Mcm 41

Praseodymium (Pr)-promoted MCM-41 catalyst was investigated for the catalytic decomposition of methyl mercaptan (CH3SH). Various characterization techniques, such as X-ray diffraction (XRD), N2 adsorption–desorption, temperature-programmed desorption of ammonia (NH3-TPD) and carbon dioxide (CO2-TPD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectrometer (XPS), were carried out to analyze the physicochemical properties of material. XPS characterization results showed that praseodymium was presented on the modified catalyst in the form of praseodymium oxide species, which can react with coke deposit to prolong the catalytic stability until 120 h. Meanwhile, the strong acid sites were proved to be the main active center over the 10% Pr/MCM-41 catalyst by NH3-TPD results during the catalytic elimination of methyl mercaptan. The possible reaction mechanism was proposed by analyzing the product distribution results. The final products were mainly small-molecule products, such as methane (CH4) and hydrogen sulfide (H2S). Dimethyl sulfide (CH3SCH3) was a reaction intermediate during the reaction. Therefore, this work contributes to the understanding of the reaction process of catalytic decomposition methyl mercaptan and the design of anti-carbon deposition catalysts.

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Oceanic phytoplankton are a potentially important source of benzenoids to the remote marine atmosphere

Communications Earth & Environment ◽

10.1038/s43247-021-00253-0 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Manon Rocco ◽

Erin Dunne ◽

Maija Peltola ◽

Neill Barr ◽

Jonathan Williams ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Dimethyl Sulfide ◽

Laboratory Culture ◽

Marine Phytoplankton ◽

Marine Atmosphere ◽

Aerosol Formation ◽

Incubation Experiments ◽

Phytoplankton Communities ◽

Anthropogenic Air Pollutants ◽

Benzene Toluene

AbstractBenzene, toluene, ethylbenzene and xylenes can contribute to hydroxyl reactivity and secondary aerosol formation in the atmosphere. These aromatic hydrocarbons are typically classified as anthropogenic air pollutants, but there is growing evidence of biogenic sources, such as emissions from plants and phytoplankton. Here we use a series of shipborne measurements of the remote marine atmosphere, seawater mesocosm incubation experiments and phytoplankton laboratory cultures to investigate potential marine biogenic sources of these compounds in the oceanic atmosphere. Laboratory culture experiments confirmed marine phytoplankton are a source of benzene, toluene, ethylbenzene, xylenes and in mesocosm experiments their sea-air fluxes varied between seawater samples containing differing phytoplankton communities. These fluxes were of a similar magnitude or greater than the fluxes of dimethyl sulfide, which is considered to be the key reactive organic species in the marine atmosphere. Benzene, toluene, ethylbenzene, xylenes fluxes were observed to increase under elevated headspace ozone concentration in the mesocosm incubation experiments, indicating that phytoplankton produce these compounds in response to oxidative stress. Our findings suggest that biogenic sources of these gases may be sufficiently strong to influence atmospheric chemistry in some remote ocean regions.

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