Notiz: A Molecular Source of CF2(X̃) at Room Temperature

The photolysis of C2H5SH liquid at 2537 Å has been shown to give H2 and C2H5SSC2H5 at equal rates with a quantum yield of 0.25. The photolysis of ethanethiol – methyl disulfide liquid mixtures leads, via a chain reaction involving propagation by attack of thiyl radicals on the disulfide S—S bond, to the formation with high quantum efficiency of CH3SH, C2H5SSC2H5 and, as an intermediate that is consumed after long exposures, CH3SSC2H5. The net result of the sequence of exchange processes is the essentially irreversible conversion of the methyl disulfide into methanethiol. The same overall reaction occurs thermally at room temperature, but the rate is appreciably less than that of the photochemical process. The quantum yields of formation of the unsymmetrical disulfides arising from the photochemically initiated exchange reaction in equimolar mixtures of CH3SSCH3 + n-C3H7SSC3H7 and C2H5SSC2H5 + n-C3H7SSC3H7 have been shown to be 6.9 and 4.4, compared to 355 for CH3-SSCH3 + C2H5SSC2H5 mixtures. In all three types of system examined in this investigation all thiyl radicals can be accounted for stoichiometrically on the basis of exchange and combination reactions alone, indicating negligible disproportionation of these species in condensed phase.

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Radiation Chemistry of Carbohydrates, X* γ-Radiolysis of Crystalline D-Glucose and D-Fructose

Zeitschrift für Naturforschung B ◽

10.1515/znb-1977-0223 ◽

1977 ◽

Vol 32 (2) ◽

pp. 213-224 ◽

Cited By ~ 33

Author(s):

M. Dizdaroglu ◽

D. Henneberg ◽

K. Neuwald ◽

G. Schomburg ◽

C. Von Sonntag

Keyword(s):

Aqueous Solution ◽

Solid State ◽

Dose Rate ◽

Gluconic Acid ◽

Room Temperature ◽

Radiation Chemistry ◽

Chain Reaction ◽

A Chain ◽

Reaction Schemes

α-D-Glucose and β-D-fructose were γ-irratiated in the solid (polycrystalline) state at room temperature at doses of 3.5 · 1020-4.2 · 1021 eV g-1 (dose rate 1.16 · 1018 eV g-1 min-1). Carbohydrate products containing ≤ 6 carbon atoms were identified and their G-values (in parentheses) measured.Glucose: Dihydroxyacetone (1) (0.05), 3-deoxy-tetrose (2) (0.015), 1,4-dideoxy-2-pentulose (3) (0.05), 2,4-dideoxy-pentose (4) (0.085), 2,4-dideoxy-pentonic acid (5), 2,3-dideoxypentos-4-ulose (6) (together 0.035), threose (7), erythrulose (8), erythrose (9), erythronic acid (10) (together 0.04), 1-deoxy-2-pentulose (11) (0.005), 2-deoxy-ribose (12) (0.25), 3-deoxy-pentosulose (18) (0.02), 3,5-dideoxy-hexonic acid (14) (0.02), 2,3-dideoxy-hexonic acid (15) (0.01), arabinose (16) (0.25), ribose (17), ribonic acid (18) (together 0.02), 2-deoxy-2-C-hydroxymethyl-pentonic acid (19) (0.06), 5-deoxy-gluconic acid (20), 2deoxy-5-keto-glucose (21), 2-deoxy-gluconic acid (22), 2-deoxy-3-keto-glucose (28), 3-deoxy-glucosone (24), 3-deoxy-gluconic acid (25), 3-deoxy-4-keto-glucose (26), 3-deoxymannonic acid (27) (together 0.4). Identified but nor measured quantitatively were glucosone (28), 3-keto-glucose (29), 4-keto-glucose (30), 5-keto-glucose (31) and gluconic acid (82). G(H2) = 5.75; G(CO2) = 0.7.Fructose: 7-9 (together 0.65), 3-deoxy-pentonic acids (37), 3-deoxy-pentosulose (88) (together 0.3), arabonic acid (89) (0.1), 18 (0.05), 6-deoxy-2,5-hexodiulose (40) (40). Identified but not measured quantitatively were glyceraldehyde (34), butanone-(3)-diol-(1,2) (35) and 2- and 3-deoxy-hexodiuloses. G(H2) = 4.75, G(CO2) = 0.05.Reaction schemes are proposed to account for the formation of the products. The scission of the hemiacetal bond and of the C-Η and C-C bonds next to it appears to be typical for solid state irradiations. The formation of deoxy-compounds is observed both in the solid state and in aqueous solution. The formation of dideoxy-compounds is only prominent in the solid state. In polycrystalline fructose a chain reaction is induced leading to 6-deoxy-2,5-hexodiulose (40).

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Towards a single step process to create high purity gold structures by electron beam induced deposition at room temperature

Nanotechnology ◽

10.1088/0957-4484/27/41/415301 ◽

2016 ◽

Vol 27 (41) ◽

pp. 415301 ◽

Cited By ~ 6

Author(s):

C Mansilla ◽

S Mehendale ◽

J J L Mulders ◽

P H F Trompenaars

Keyword(s):

Electron Beam ◽

High Purity ◽

Room Temperature ◽

Single Step ◽

Step Process ◽

Electron Beam Induced Deposition

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Observations on a Relationship between Steroid Metabolism and the Concentration of Plasma Fibrinogen

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654793 ◽

1963 ◽

Vol 10 (02) ◽

pp. 400-405 ◽

Cited By ~ 4

Author(s):

B. A Amundson ◽

L. O Pilgeram

Keyword(s):

Blood Coagulation ◽

Methyl Ether ◽

Broad Spectrum ◽

Human Subjects ◽

Plasma Fibrinogen ◽

Steroid Metabolism ◽

Specific Site ◽

Chain Reaction ◽

Normal Human ◽

A Chain

SummaryEnovid (5 mg norethynodrel and 0.075 mg ethynylestradiol-3-methyl ether) therapy in young normal human subjects causes an increase in plasma fibrinogen of 32.4% (P >C 0.001). Consideration of this effect together with other effects of Enovid on the activity of specific blood coagulatory factors suggests that the steroids are exerting their effect at a specific site of the blood coagulation and/or fibrinolytic system. The broad spectrum of changes which are induced by the steroids may be attributed to a combination of a chain reaction and feed-back control.

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New Potential Biologically Active Compounds: Synthesis and Characterization of Urea and Thiourea Derivativpes Bearing 1,2,4-oxadiazole Ring

Current Organic Synthesis ◽

10.2174/1570179417666200417112106 ◽

2020 ◽

Vol 17 (7) ◽

pp. 525-534 ◽

Cited By ~ 1

Author(s):

Nevin Arıkan Ölmez ◽

Faryal Waseer

Keyword(s):

Microwave Irradiation ◽

Room Temperature ◽

Antimicrobial Activities ◽

Phenyl Isocyanate ◽

Single Step ◽

Biologically Active Compounds ◽

Biologically Active ◽

Active Compounds ◽

Thiourea Derivatives ◽

Acyl Chlorides

Background: Urea, thiourea, and 1,2,4-oxadiazole compounds are of great interest due to their different activities such as anti-inflammatory, antiviral, analgesic, fungicidal, herbicidal, diuretic, antihelminthic and antitumor along with antimicrobial activities. Objective: In this work, we provide a new series of potential biologically active compounds containing both 1,2,4-oxadiazole and urea/thiouprea moiety. Materials and Methods: Firstly, 5-chloromethyl-3-aryl-1,2,4-oxadiazoles (3a-j) were synthesized from the reaction of different substituted amidoximes (2a-j) and chloroacetyl chloride in the presence of pyridine by conventional and microwave-assisted methods. In the conventional method, 1,2,4-oxadiazoles were obtained in two steps. O-acylamidoximes obtained in the first step at room temperature were heated in toluene for an average of one hour to obtain 1,2,4-oxadiazoles. The yields varied from 70 to 96 %. 1,2,4-oxadiazoles were obtained under microwave irradiation in a single step in a 90-98 % yield at 160 °C in five minutes. 5-aminomethyl-3-aryl-1,2,4- oxadiazoles (5a-j) were obtained by Gabriel amine synthesis in two steps from corresponding 5-chloromethyl-3- aryl-1,2,4-oxadiazoles. Finally, twenty new urea (6a-j) and thiourea (7a-j) compounds bearing oxadiazole ring were synthesized by reacting 5-aminomethyl-3-aryl-1,2,4-oxadiazoles with phenyl isocyanate and isothiocyanate in tetrahydrofuran (THF) at room temperature with average yields (40-70%). Results and Discussions: An efficient and rapid method for the synthesis of 1,2,4-oxadiazoles from the reaction of amidoximes and acyl halides without using any coupling reagent under microwave irradiation has been developed, and twenty new urea/thiourea compounds bearing 1,2,4-oxadiazole ring have been synthesized and characterized. Conclusion: We have synthesized a new series of urea/thiourea derivatives bearing 1,2,4-oxadiazole ring. Also facile synthesis of 3,5-disubstituted 1,2,4-oxadiazoles from amidoximes and acyl chlorides under microwave irradiation was reported. The compounds were characterized using FTIR, 1H NMR, 13C NMR, and elemental analysis techniques.

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Pathogenesis and Management of COVID-19

Journal of Xenobiotics ◽

10.3390/jox11020006 ◽

2021 ◽

Vol 11 (2) ◽

pp. 77-93

Author(s):

Khalid O. Alfarouk ◽

Sari T. S. AlHoufie ◽

Samrein B. M. Ahmed ◽

Mona Shabana ◽

Ahmed Ahmed ◽

...

Keyword(s):

Multiple Organ Failure ◽

Human Body ◽

Inflammatory Mediators ◽

Expression Patterns ◽

Multiple Organ ◽

Cytokine Storm ◽

Chain Reaction ◽

Road Map ◽

A Chain ◽

Global War

COVID-19, occurring due to SARS-COV-2 infection, is the most recent pandemic disease that has led to three million deaths at the time of writing. A great deal of effort has been directed towards altering the virus trajectory and/or managing the interactions of the virus with its subsequent targets in the human body; these interactions can lead to a chain reaction-like state manifested by a cytokine storm and progress to multiple organ failure. During cytokine storms the ratio of pro-inflammatory to anti-inflammatory mediators is generally increased, which contributes to the instigation of hyper-inflammation and confers advantages to the virus. Because cytokine expression patterns fluctuate from one person to another and even within the same person from one time to another, we suggest a road map of COVID-19 management using an individual approach instead of focusing on the blockbuster process (one treatment for most people, if not all). Here, we highlight the biology of the virus, study the interaction between the virus and humans, and present potential pharmacological and non-pharmacological modulators that might contribute to the global war against SARS-COV-2. We suggest an algorithmic roadmap to manage COVID-19.

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