Journal articles: 'Oxirane compounds'

1

Rinald, Andrew, Victor Terskikh, Gabriele Schatte, and Gang Wu. "A combined solid-state 17O NMR, crystallographic, and computational study of oxiranes." Canadian Journal of Chemistry 98, no. 8 (August 2020): 434–40. http://dx.doi.org/10.1139/cjc-2020-0114.

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We report the synthesis and solid-state 17O NMR characterization of three 17O-labeled oxiranes: (2S*,3S*)-2,3-bis(4-nitrophenyl)-[17O]oxirane, (2S*,3R*)-2,3-bis(4-nitrophenyl)-[17O]oxirane, and 2,2,3-triphenyl-[17O]oxirane. In addition, we have determined the crystal structure of (2S*,3R*)-2,3-bis(4-nitrophenyl)oxirane by X-ray crystallography. When the experimentally determined 17O NMR tensors for oxiranes (where the C–O–C bond angle is about 60°) are compared with those for dimethyl ether (where the C–O–C bond angle is 113°) and other R–O–R′ functional groups, we found that the highly constrained geometry of oxiranes results in distinct tensor orientations in the molecular frame of reference. The experimental results are complemented by quantum chemical computations. This study represents the first time that 17O chemical shift and quadrupole coupling tensors are simultaneously determined for oxirane compounds.

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2

Dawid, Malgorzata, and John Warkentin. "Intramolecular reactions of dialkoxycarbenes with a carbonyl group." Canadian Journal of Chemistry 81, no. 6 (June 1, 2003): 598–606. http://dx.doi.org/10.1139/v02-200.

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Thermolysis of 5,5-dimethyl-2-methoxy-2-(2-oxocyclohexylmethoxy)-Δ3-1,3,4-oxadiazoline (3a) in benzene at 110°C generated a carbonyl ylide intermediate that gave, in a minor side reaction, a product of 1,3-dipolar cycloaddition to the carbonyl group. The major fate of the ylide was fragmentation to acetone and a dialkoxycarbene, MeO (RCH2O)C:, where R = 2-oxocyclohexyl. The carbene, in turn, underwent overall [2 + 1] cycloaddition to the carbonyl group, presumably to afford diastereomeric dialkoxyoxiranes that could not be isolated. A product of methanolysis of the presumed oxiranes was isolated by GC and its structure was determined by means of X-ray diffraction. Methanol is believed to result from reaction of an intermediate or product with adventitious water. Deliberate hydrolysis of the product of methanolysis gave a hydroxy lactone, the structure of which was also secured by means of single crystal X-ray diffraction. Those structures indicated the likely structures of the oxirane precursors. A second, and major, product from the carbene was a bicyclic ketone. Similar products were obtained from intramolecular reactions of a carbene tethered to cyclopentanone through a two-carbon or a one-carbon tether. Some compounds that are apparently "dimers" of the oxiranes were also isolated and identified by means of X-ray diffraction. These dimers are thought to originate from the reaction of a ring-opened oxirane (a dipole or a cation from electrophilic opening of the oxirane) with a molecule of the oxirane rather than from bimolecular reaction between two oxirane molecules. The oxiranes open by cleavage of the (RO)2CO bond rather than the oxirane CC bond, the normally observed sense of thermal ring opening. The properties of the carbenes and the presumed oxiranes serve to point out the options available to such intermediates and suggest that some new, synthetically useful reactions may become possible.Key words: bicyclic ketone, dialkoxycarbene, dialkoxyoxirane, hydroxylactone, "oxirane dimers".

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3

Khalili, Gholamhossein, Patrick McCosker, Timothy Clark, and Paul Keller. "Synthesis and Density Functional Theory Studies of Azirinyl and Oxiranyl Functionalized Isoindigo and (3Z,3’Z)-3,3’-(ethane-1,2-diylidene)bis(indolin-2-one) Derivatives." Molecules 24, no. 20 (October 10, 2019): 3649. http://dx.doi.org/10.3390/molecules24203649.

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The design and synthesis of functionalized isoindigo compounds by reaction of isoindigo with (S)-glycidyl tosylate, epibromohydrin, 2-(bromomethyl)-1-(arylsulfonyl)aziridine, and 2-(bromomethyl)-1-(alkylsulfonyl)aziridine in the presence of MeONa proceed under mild conditions in moderate yields. (3Z,3’Z)-3,3’-(Ethane-1,2-diylidene)bis(1-(oxiran-2-ylmethyl)indolin-2-one), with an extended central olefin π-conjugated moiety was also reacted with methyl-oxiranes to give the corresponding N,N’-disubstituted derivative. Calculations with DFT and TD-DFT of hypothetical isoindigo-thiophene DA molecules with various electron withdrawing substituents, including aziridine, oxirane, nitrile, carbonyl, and sulfonate, indicated that the proximity and strength of the functional group have a significant effect on the HOMO, LUMO, vertical excitation energy, and oscillator strength of the π–π* transitions.

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4

David, Michèle, Jean Sauleau, and Armelle Sauleau. "Époxydes α-éthyléniques et phénate de sodium: accès à des éthers phénoliques et phénols ortho-allyliques." Canadian Journal of Chemistry 63, no. 9 (September 1, 1985): 2449–54. http://dx.doi.org/10.1139/v85-405.

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The ring cleavage reactions of α-ethylenic epoxides by sodium phenoxide afforded a mixture of products. Problems of competitive attack by this nucleophile, at the less substituted carbon (compounds A) or at the β-ethylenic carbon atom (compounds B and C), were encountered and could be resolved by judicious choice of reaction conditions (solvents, stereochemistry of the oxiranes). The regioselectivity of the attack was dependent on the transition states, implying weak steric hindrance and a conjugation oxirane – double bond.

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5

Weigand, Wolfgang, Ulrich Nagel, and Wolfgang Beck. "Pseudohalogeno-Metallverbindungen, LXVIII [1]. Reaktionen der Cyanometallsäuren NCAuCNH, (NC)4Pt(CNH)2, (NC)2M(CNH)4(M = Fe, Ru, Os) und Co[bis(dimethyIglyoximato)](CN)CNHmit Epoxiden: 2-Hydroxyalkylisocyanid- und Oxazolidin-2-yIiden-MetalIkomplexe / Pseudohalogeno Metal Compounds, LXVIII [1]. Reaction of Cyano Metal Acids NCAuCNH, (NC)4Pt(CNH)2, (NC)2M(CNH)4 (M = Fe, Ru, Os) and Co[bis(dimethylglyoximato)](CN)CNH with Epoxides: 2-Hydroxyalkylisocyanide and Oxazolidine-2-ylidene Metal Complexes." Zeitschrift für Naturforschung B 43, no. 3 (March 1, 1988): 328–38. http://dx.doi.org/10.1515/znb-1988-0316.

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NCAuCNH reacts with expoxides to give oxazolidine-2-ylidene (2) and 2-hydroxyalkyl complexes (3), respectively. Complexes with cyclic carbene ligands [XXX] (5) and [XXX] (7) are formed from the corresponding isocyanic metal compounds and oxiranes. 5b has been characterized by crystal structure determination. Ring opening of phenyloxirane occurs at the phenyl substituted carbon atom. (NC)2M(CNH)4 (M = Fe, Ru, Os) and oxirane yield mixtures of [XXX] and [XXX].

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6

El-Sayed, Amira A., Maher A, El Hashash, and Sameh A. Rizk. "Ultrasonic and solvent free Synthesis of Regioselective Diastereomeric Adducts and Heterocyclic Products as antibacterial agent." JOURNAL OF ADVANCES IN CHEMISTRY 13, no. 2 (June 9, 2017): 5977–88. http://dx.doi.org/10.24297/jac.v13i12.6152.

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Oxirane ring containing the carboxylic group in the Î±,Î²-position are useful intermediates in the synthesis of biologically active compounds. Epoxidation of 4-(4-acetylamino and/or bromophenyl)-4-oxo-but-2-enoic acids via ultrasound condition afforded Î±-oxirane carboxylic acid followed by regioselective diastereomeric adducts of camphor. The steric factor plays an important role in regioselectivity. Formation of oxirane and furan derivatives via ultrasonic condition was considered as key steps for synthesis of some important heterocyclic compounds. The structure of new synthesized compounds 2-9a,b were elucidated by elemental analysis and spectroscopic data. The antibacterial activity for the synthesized compounds was evaluated.

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7

Gyuranová, Dominika, Radka Štadániová, Zuzana Hegyi, Róbert Fischer, and Martin Rebroš. "Production of Enantiopure Chiral Epoxides with E. coli Expressing Styrene Monooxygenase." Molecules 26, no. 6 (March 10, 2021): 1514. http://dx.doi.org/10.3390/molecules26061514.

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Styrene monooxygenases are a group of highly selective enzymes able to catalyse the epoxidation of alkenes to corresponding chiral epoxides in excellent enantiopurity. Chiral compounds containing oxirane ring or products of their hydrolysis represent key building blocks and precursors in organic synthesis in the pharmaceutical industry, and many of them are produced on an industrial scale. Two-component recombinant styrene monooxygenase (SMO) from Marinobacterium litorale was expressed as a fused protein (StyAL2StyB) in Escherichia coli BL21(DE3). By high cell density fermentation, 35 gDCW/L of biomass with overexpressed SMO was produced. SMO exhibited excellent stability, broad substrate specificity, and enantioselectivity, as it remained active for months and converted a group of alkenes to corresponding chiral epoxides in high enantiomeric excess (˃95–99% ee). Optically pure (S)-4-chlorostyrene oxide, (S)-allylbenzene oxide, (2R,5R)-1,2:5,6-diepoxyhexane, 2-(3-bromopropyl)oxirane, and (S)-4-(oxiran-2-yl)butan-1-ol were prepared by whole-cell SMO.

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8

Askerov, O. V., A. F. Mamedova, and D. R. Nurullayeva. "SYNTHESIS AND PROPERTIES OF ORGANOSILICON EPISULFIDES." Azerbaijan Chemical Journal, no. 4 (December 8, 2021): 43–48. http://dx.doi.org/10.32737/0005-2531-2021-4-43-48.

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A study was made of the interaction of thiourea with saturated and unsaturated organosilicon oxiranes in absolute methyl alcohol in a medium of potassium hydroxide, and methods were developed for the synthesis of unsaturated and unsaturated organosilicon silicides with a yield of 65–75%.The studies carried out revealed that the synthesized organosilicon episulfides are very reactive compounds and can react with nucleophilic and electrophilic reagents, while forming the corresponding silicon derivatives. The IR- spectra of the products were studied. It should be noted that, when comparing the IR- spectra of oxiranes and episulfides, it was revealed that the stretching vibrations of the CH2 group of the episulfide ring are underestimated by 50–70 cm-1 in comparison with the oxirane ring

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9

Tan, Xiaojun, Mengyao Wu, Yilin Wang, Guizhi Shi, and Jinsong Gu. "Theoretical study on the reaction between silacyclopropenylidene and three-membered heterocyclic compounds (azirane and oxirane): An alternative approach to the formation of heterocyclic silylene." Progress in Reaction Kinetics and Mechanism 45 (January 2020): 146867832090205. http://dx.doi.org/10.1177/1468678320902059.

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The reaction mechanism between silacyclopropenylidene and three-membered heterocyclic compounds (azirane and oxirane) has been systematically investigated at the B3LYP/6-311+G* level of theory in order to better understand the reactivity of unsaturated cyclic silylene. Geometry optimizations and vibrational analyses have been conducted for the stationary points on the potential energy surface of the system. Calculations show that the Si-spiroheterocyclic intermediate and four-membered heterocyclic silylene compound could be produced through the insertion process and subsequent dissociation process between silacyclopropenylidene and three-membered heterocyclic compounds. For the insertion process, it is easier for silacyclopropenylidene to insert into C-N bond of azirane than into C-O bond of oxirane. This study is helpful to understand the reactivity of silacyclopropenylidene, the evolution of silicon-bearing molecules in space, and to offer an alternative approach to the formation of enlarged heterocyclic silylene compound.

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10

Emblem, H. G., and N. A. Hurt. "Reactions of aminoalkyl silicates with oxirane compounds." Journal of Applied Chemistry 12, no. 8 (May 4, 2007): 366–73. http://dx.doi.org/10.1002/jctb.5010120805.

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11

Shivanyuk, Alexander, Andrii Gerasov, Rodion Boiko, Grygoriy Dolgonos, Aleksandr Mandzhulo, Volodymyr Fetyukhin, and Oleg Lukin. "Tropane-Based Dispirocyclic Oxiranes and Spirocyclic Ketones." Synthesis 54, no. 03 (December 6, 2021): 723–31. http://dx.doi.org/10.1055/s-0040-1719848.

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AbstractThe Prilezhaev epoxidation of N-Boc-protected 3-cyclobutylidenetropane 1a affords a 1:2 mixture of compounds 2a and 2b, in which tropane and cyclobutane fragments are spiro-connected to the oxirane ring in endo- and exo-fashion, respectively. The exo-isomer 2b is obtained in 89% yield and 97% selectivity via the dioxirane oxidation of 1a. BF3-catalyzed isomerization of exo-oxirane 2b results in a 1:1 mixture of the spirocyclic ketones endo 3a and exo 3b containing spiro-connected tropane and cyclopentanone rings, while endo-epoxide 2a gives exclusively endo-ketone 3a. Prilezhaev and dioxirane epoxidations of N-Boc-protected 3-cyclopropylidenetropane 1b affords a mixture of endo- and exo-oxiranes 2c and 2d. Compounds 2c and 2d are not isolated in individual forms since they isomerize into a mixture of spirocyclic ketones endo 3c and exo 3d. Removal of the Boc groups from ketones 3a–d gives the corresponding hydrochlorides of aminoketones 4a–d in quantitative yields. Quantum chemical calculations predict that the rearrangement of endo-epoxides into the corresponding endo-ketones involving BF3-containing intermediates has by 4.4–7.9 kcal/mol lower activation barriers than the respective conversion of the exo-epoxides into exo-ketones. The cyclopropyl-containing dispiroepoxides 2c and 2d are predicted to interconvert faster into the corresponding ketones compared to their less strained cyclobutyl counterparts 2a and 2b.

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12

Mali, Suraj N., Sudhir Sawant, Hemchandra K. Chaudhari, and Mustapha C. Mandewale. "In Silico Appraisal, Synthesis, Antibacterial Screening and DNA Cleavage for 1,2,5-thiadiazole Derivative." Current Computer-Aided Drug Design 15, no. 5 (September 23, 2019): 445–55. http://dx.doi.org/10.2174/1573409915666190206142756.

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Background: : Thiadiazole not only acts as “hydrogen binding domain” and “two-electron donor system” but also as constrained pharmacophore. Methods:: The maleate salt of 2-((2-hydroxy-3-((4-morpholino-1, 2,5-thiadiazol-3-yl) oxy) propyl) amino)- 2-methylpropan-1-ol (TML-Hydroxy)(4) has been synthesized. This methodology involves preparation of 4-morpholino-1, 2,5-thiadiazol-3-ol by hydroxylation of 4-(4-chloro-1, 2,5-thiadiazol-3-yl) morpholine followed by condensation with 2-(chloromethyl) oxirane to afford 4-(4-(oxiran-2-ylmethoxy)-1,2,5-thiadiazol- 3-yl) morpholine. Oxirane ring of this compound was opened by treating with 2-amino-2-methyl propan-1- ol to afford the target compound TML-Hydroxy. Structures of the synthesized compounds have been elucidated by NMR, MASS, FTIR spectroscopy. Results: : The DSC study clearly showed that the compound 4-maleate salt is crystalline in nature. In vitro antibacterial inhibition and little potential for DNA cleavage of the compound 4 were explored. We extended our study to explore the inhibition mechanism by conducting molecular docking, ADMET and molecular dynamics analysis by using Schrödinger. The molecular docking for compound 4 showed better interactions with target 3IVX with docking score of -8.508 kcal/mol with respect to standard ciprofloxacin (docking score= -3.879 kcal/mol). TML-Hydroxy was obtained in silico as non-carcinogenic and non-AMES toxic with good percent human oral absorption profile (69.639%). TML-Hydroxy showed the moderate inhibition against Mycobacteria tuberculosis with MIC 25.00 μg/mL as well as moderate inhibition against S. aureus, Bacillus sps, K. Pneumoniae and E. coli species. Conclusion: : In view of the importance of the 1,2,5-thiadiazole moiety involved, this study would pave the way for future development of more effective analogs for applications in medicinal field.

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13

Ha, Hyun-Joon. "Preface to “Aziridine Chemistry”." Molecules 26, no. 6 (March 11, 2021): 1525. http://dx.doi.org/10.3390/molecules26061525.

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14

Meissner, Albrecht, Peter Scholz, and Bernd Ondruschka. "Incorporation of CO2 Into Various Terminal and Internal Epoxides." Collection of Czechoslovak Chemical Communications 73, no. 1 (2008): 88–96. http://dx.doi.org/10.1135/cccc20080088.

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Carbon dioxide was incorporated into various oxirane-containing compounds. The starting materials include natural products with epoxy groups (1-4), glycidyl compounds (5-9) and epoxidized polymers (9, 10). It could be shown that the crosslinking side reaction is not significant for internal epoxides but important for terminal glycidyl compounds.

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15

Wang, Zhen, Jian Wen, Qing-Wei Bi, Xiao-Qi Xu, Zhu-Qing Shen, Xiao-Xiao Li, and Zili Chen. "Oxirane synthesis from diazocarbonyl compounds via NHC-Ag+ catalysis." Tetrahedron Letters 55, no. 18 (April 2014): 2969–72. http://dx.doi.org/10.1016/j.tetlet.2014.03.105.

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16

Bělohradský, Martin, Petr Holý, Ivan Stibor, and Jiří Závada. "A versatile synthesis of oligocrown compounds with hydroxyl groups at the hinge." Collection of Czechoslovak Chemical Communications 52, no. 12 (1987): 2961–70. http://dx.doi.org/10.1135/cccc19872961.

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Oxirane ring-opening reaction of N-(2,3-epoxy-1-propyl) azacrowns Ia-Ic and 4,5-epoxy-2-oxapentylcrowns IIa-IIe with mono- and diamines (including mono- and diazacrowns) afforded array of new di-, tri-, and tetracrown compounds with hydroxyl groups placed at the hinge.

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17

Djurendić, Evgenija A., Marina P. Zaviš, Marija N. Sakač, Vesna V. Kojić, Gordana M. Bogdanović, and Katarina M. Penov Gaši. "Synthesis and Biological Evaluation of Some A,D-Ring Modified 16,17-Secoandrostane Derivatives." Collection of Czechoslovak Chemical Communications 73, no. 5 (2008): 627–36. http://dx.doi.org/10.1135/cccc20080627.

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Starting from 3β-hydroxy-17-oxo-16,17-secoandrost-5-ene-16-nitrile (1), the new 16,17-secoandrostane derivatives 2-11 were synthesized. Protection of the 17-oxo function of compound 1 with ethylene glycol yielded compounds 2 and 3. The Oppenauer oxidation of 2 or oxidation with H2O2 in alkaline conditions gave the respective compounds 4 and 10. Epoxidation of compound 4 yielded a mixture of 4α,5α- and 4β,5β-epoxides 5 and 6 and a mixture of 4α,5α- and 4β,5β-epoxy-carboxamides 7 and 8. Opening of the oxirane ring of a mixture of compounds 5 and 6 with formic acid afforded the 4-hydroxy derivative 9. Anti-aromatase activity and in vitro cytotoxicity for three tumor cell lines (human breast adenocarcinoma ER+, MCF-7 as well as human breast adenocarcinoma ER-, MDA-MB-231, and prostate cancer, PC3) of selected compounds were evaluated. Compounds 2, 4, 9, and 10 showed a strong cytotoxicity for PC3 cells.

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18

Čižmáriková, Ružena, Alois Borovanský, Ján Kozlovský, Eva Béderová, and Anna Dingová. "4-(3-Alkylamino-2-hydroxypropoxy)-3-(alkoxymethyl)acetophenones." Collection of Czechoslovak Chemical Communications 50, no. 10 (1985): 2289–98. http://dx.doi.org/10.1135/cccc19852289.

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A series of new beta-adrenolytics derived from p-hydroxyacetophenone was synthesized by four methods. The most advantageous was found to be the five-step synthesis via reaction of the intermediate oxirane with amines. The selected compounds reveal a beta-adrenolytic and antiarrhythmic activities.

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19

Chalupová, Šárka, Antonín Holý, and Milena Masojídková. "Synthesis of Some N4-Substituted Derivatives of 1-[(S)-3-Hydroxy-2-(phosphonomethoxy)propyl]cytosine (HPMPC, Cidofovir)." Collection of Czechoslovak Chemical Communications 70, no. 12 (2005): 2053–65. http://dx.doi.org/10.1135/cccc20052053.

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N4-Substituted derivatives of HPMPC were synthesized in four-step synthesis which included treatment of 4-methoxypyrimidin-2(1H)-one (1) with (S)-[(trityloxy)methyl]oxirane in DMF. Condensation of intermediary 1-[2-hydroxy-3-(trityloxy)propyl]-4-methoxypyrimidin-2(1H)-one (2) with (diisopropoxyphosphoryl)methyl tosylate in the presence of sodium hydride resulted in fully protected 4-methoxypyrimidin-2(1H)-one derivative 3 which gave on reaction with an appropriate primary amine in dioxane N4-substituted products 4a-4i. The reaction with bromotrimethylsilane simultaneously cleaved the trityl group and deprotected the phosphonate residue and gave the title HPMP analogues substituted at the cytosine amino group in position N4 5a-5i. Compound 4j was prepared from 4-methoxypyrimidin-2(1H)-one (1) by reaction with cyclopropylamine in dioxane. The intermediary 4-(cyclopropylamino)pyrimidin-2(1H)-one (6) then reacts with (S)-[(trityloxy)methyl]oxirane in DMF. Fully protected phosphonate 4j and its deprotected counterpart 5j was obtained by the same sequence of reactions as in the case of compounds 5a-5i.

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20

Skachko, Stanislav, Orest Hevus, and Larysa Dolynska. "Novel Functional Derivatives of Methyl-cis-9,10-Epoxy-Octadecanoate." Chemistry & Chemical Technology 4, no. 3 (September 15, 2010): 167–70. http://dx.doi.org/10.23939/chcht04.03.167.

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The synthesis of functional derivatives of epoxystearic acid methyl ester by oxirane ring opening and transesterification of ester group has been described. Some novel surface-active and peroxide-containing compounds have been obtained. Major features of the process have been investigated and main characteristics have been determined.

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21

Wang, Zhen, Jian Wen, Qing-Wei Bi, Xiao-Qi Xu, Zhu-Qing Shen, Xiao-Xiao Li, and Zili Chen. "ChemInform Abstract: Oxirane Synthesis from Diazocarbonyl Compounds via NHC-Ag+Catalysis." ChemInform 45, no. 42 (October 2, 2014): no. http://dx.doi.org/10.1002/chin.201442104.

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22

Swinarew, Andrzej, Beata Swinarew, Jadwiga Gabor, Magdalena Popczyk, Klaudia Kubik, Arkadiusz Stanula, Zbigniew Waśkiewicz, Thomas Rosemann, and Beat Knechtle. "New Kind of Polymer Materials Based on Selected Complexing Star-Shaped Polyethers." Polymers 11, no. 10 (September 24, 2019): 1554. http://dx.doi.org/10.3390/polym11101554.

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In today’s analytical trends, there is an ever-increasing importance of polymeric materials for low molecular weight compounds including amines and drugs because they can act as carriers or capture amines or drugs. The use of this type of materials will allow the development of modern materials for the chromatographic column beds and the substrates of selective sensors. Moreover, these kinds of materials could be used as a drug carrier. Therefore, the aim of this study is presenting the synthesis and complexing properties of star-shaped oxiranes as a new sensor for the selective complexation of low molecular weight compounds. Propylene oxide and selected oxirane monomers with carbazolyl in the substituent were selected as the monomers in this case and tetrahydrofuran as its solvent. The obtained polymer structures were characterized using the MALDI-TOF. It was found that in the initiation step potassium hydride deprotonates the monomer molecule and takes also part in the nucleophilic substitution. The resulting polymeric material preferably cross-linked with selected di-oxiranes (1,2,7,8-diepoksyoktan in respect ratio 3:1 according to active center) was then used as a stationary phase in the column and thin layer chromatography for amine separation and identification. Sorption ability of the resulting deposits was determined using a quartz microbalance (QCMB). The study was carried out in stationary mode and flow cells to simulate actual operating phase conditions. Based on changes in electrode vibration frequency, the maximum amount of adsorbed analyte and the best conditions for its sorption were determined.

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Prabha, S., and J. Kumar. "Gas Chromatographic and Mass Spectroscopic (GC-MS) Analysis of Rhizome of Acorus Calamus Linn. for Identification of Potent Antimicrobial Bio-active Compounds." Journal of Scientific Research 13, no. 1 (January 1, 2021): 263–73. http://dx.doi.org/10.3329/jsr.v13i1.48452.

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Acorus calamus Linn. has wide applications as a herbal medicine since its roots, leaves and rhizome exhibit antimicrobial and insecticidal activities. The objective of this study was to identify some compounds in Acorus calamus Linn., which may be responsible for its antimicrobial activity. Gas Chromatography-Mass Spectroscopy (GC-MS) analysis, for investigation of the compounds present, of the petroleum ether extract of Acorus calamus Linn. rhizome suggested presence of five compounds (which showed close match with those of the GC-MS database main library of Novocatalyz) viz., spiro [2,4,5,6,7,7a-hexahydro-2-oxo-4,4,7a-trimethylbenzofuran]-7,2' -(oxirane); 9-octadecenoic acid (Z)-, phenylmethyl ester; shyobunone; asarone [syn. α-asarone]; benzene, 1,2,3-trimethoxy-5-(2-propenyl)-. α-asarone and benzene, 1,2,3-trimethoxy-5-(2-propenyl)- have been reported to be sensitive against plant pathogen and may be responsible for its anti-fungal activity. As per the compound contents of this plant, studies suggest that Acorus calamus Linn. could be a potential herbal medicine against certain microbial diseases.

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Prabha, S., and J. Kumar. "Gas Chromatographic and Mass Spectroscopic (GC-MS) Analysis of Rhizome of Acorus Calamus Linn. for Identification of Potent Antimicrobial Bio-active Compounds." Journal of Scientific Research 13, no. 1 (January 1, 2021): 263–73. http://dx.doi.org/10.3329/jsr.v13i1.48452.

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Acorus calamus Linn. has wide applications as a herbal medicine since its roots, leaves and rhizome exhibit antimicrobial and insecticidal activities. The objective of this study was to identify some compounds in Acorus calamus Linn., which may be responsible for its antimicrobial activity. Gas Chromatography-Mass Spectroscopy (GC-MS) analysis, for investigation of the compounds present, of the petroleum ether extract of Acorus calamus Linn. rhizome suggested presence of five compounds (which showed close match with those of the GC-MS database main library of Novocatalyz) viz., spiro [2,4,5,6,7,7a-hexahydro-2-oxo-4,4,7a-trimethylbenzofuran]-7,2' -(oxirane); 9-octadecenoic acid (Z)-, phenylmethyl ester; shyobunone; asarone [syn. α-asarone]; benzene, 1,2,3-trimethoxy-5-(2-propenyl)-. α-asarone and benzene, 1,2,3-trimethoxy-5-(2-propenyl)- have been reported to be sensitive against plant pathogen and may be responsible for its anti-fungal activity. As per the compound contents of this plant, studies suggest that Acorus calamus Linn. could be a potential herbal medicine against certain microbial diseases.

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Eom, Taejun, and Anzar Khan. "Selenium-Epoxy ‘Click’ Reaction and Se-Alkylation—Efficient Access to Organo-Selenium and Selenonium Compounds." Chemistry 2, no. 4 (October 5, 2020): 827–36. http://dx.doi.org/10.3390/chemistry2040054.

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This work establishes the ‘click’ nature of the base-catalyzed oxirane ring opening reaction by the selenolate nucleophile. The ‘click’-generated ß-hydroxy selenide can be alkylated to afford cationic selenium species. Hemolytic studies suggest that selenonium cations do not lyse red blood cells even at high concentrations. Overall, these results indicate the future applicability of the developed organo-selenium chemistry in the preparation of a new class of cationic materials based on the seleno-ether motif.

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Lange, C. "Oxirane as a chemical ionization gas: Reactivity towards different classes of compounds." Organic Mass Spectrometry 28, no. 11 (November 1993): 1285–96. http://dx.doi.org/10.1002/oms.1210281102.

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Allen, Anthony A., and Frederick Kurzer. "Diisophorone and related compounds. Part 15 2,7-Epoxydiisophoranes: Oxirane cleavage byGrignard reagents." Monatshefte f�r Chemie Chemical Monthly 116, no. 6-7 (1985): 777–87. http://dx.doi.org/10.1007/bf00809155.

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28

Ondrus, Theodore A., Purushottam R. Pednekar, and Edward E. Knaus. "Some reactions of 1-methyl-1,2-dihydropyridines with organic azides. Synthesis and reactions of 1,2,5,6-tetrahydropyridylidene-2-cyan(sulfon)amides and piperidylidene-2-cyan(sulfon)amides." Canadian Journal of Chemistry 63, no. 9 (September 1, 1985): 2362–68. http://dx.doi.org/10.1139/v85-391.

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The regiospecific 1,3-dipolar cycloaddition reaction of 1,2-dihydropyridines 2 with organic azides 3 affords 2,7-diazabicyclo[4.1.0]hept-4-enes 4. Treatment of 4a with neutral aluminum oxide opened the aziridine ring to afford the 1,2,5,6-tetrahydropyridylidene-2-cyanamide 5. Catalytic hydrogenation of 4 and 5 using palladium-on-charcoal and hydrogen yielded the 1-methyl-2-piperidylidenes 6. Oxidation of 1-methyl-1,2,5,6-tetrahydropyridylidene-2-cyanamide (5) with alkaline hydrogen peroxide yielded the oxirane 7 arising from epoxidation of the 3,4-olefenic bond, whereas oxidation of the bicyclic aziridine 4a with m-chloroperbenzoic acid resulted in epoxidation of the 4,5-olefenic bond and opening of the aziridine ring to give the oxirane 3-methyl-3-aza-7-oxabicyclo[4.1.0]heptylidene-4-cyanamide (10). Base-catalyzed abstraction of the C-3 proton of 1-methyl-2-piperidylidenes 6 yielded the 3-lithio analogs which, after bromination, were converted to the target compounds 18 upon condensation with 4-[(2-aminoethyl)thiomethyl]-5-methylimidazole.

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Hilton, James L., Parthasarathy Pillai, and Helen A. Norman. "Fate of Safening Agent L-2-Oxothiazolidine-4-Carboxylic Acid in Sorghum (Sorghum bicolor)." Weed Science 38, no. 3 (May 1990): 201–5. http://dx.doi.org/10.1017/s004317450005640x.

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The herbicide safener OTC (L-2-oxothiazolidine-4-carboxylic acid) increased the amount of reduced thiol compounds in sorghum [Sorghum bicolor(L.) Moench. ‘DK 427′] seedlings. When seedlings were grown in liquid culture medium containing35S-OTC, the compound was metabolized to radiolabeled cysteine and glutathione. The addition of tridiphane [2-(3,5-dichlorophenyl)-2-(2,2,2-trichloroethyl)oxirane] increased conversion of35S-OTC to cysteine and resulted in the formation of one additional35S-labeled compound. When35S-glutathione was injected into germinating seeds it was converted to35S-cysteine and both thiols were subsequently found in roots and shoots. Seeds injected with35S-OTC both translocated the compound to developing roots and shoots and metabolized35S-OTC to cysteine and glutathione. Excised roots and shoots also metabolized35S-OTC to the thiols. In an in vitro assay the enzyme 5-oxoprolinase converted OTC to cysteine.

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Pandya, Dhananjay, and Yogesh Naliapara. "Synthesis and Anti Lung Cancer Activity of 3-Arylspiro[oxirane-2,3'- thiochroman]-4'-one Derivatives." Letters in Organic Chemistry 16, no. 6 (April 23, 2019): 517–24. http://dx.doi.org/10.2174/1570178616666181130163914.

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A series of 3-arylspiro[oxirane-2,3'-thiochroman]-4'-one derivatives were synthesized and characterized by spectroscopy like 1H NMR, 13C NMR, mass spectrometry and elemental analysis. They were evaluated for their anti-lung cancer activity on human lung cancer cell line A-549 in DMSO. Compounds under study were found to be potent anti-lung cancer agents with GI50 values less than 10 with respect to positive control adriamycin.

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Okopi, S. O., and L. M. Affiku. "Synthesis and Olfactory Characteristics of Hydroxyether Derivatives of Methyl Eugenol." Journal of Applied Sciences and Environmental Management 24, no. 9 (October 16, 2020): 1503–7. http://dx.doi.org/10.4314/jasem.v24i9.3.

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Methyl eugenol is a naturally occurring substance found in the essential oils of several plant species. It is a cheap and abundant material with a rather limited interest as perfuming ingredient. This research investigated the structure-odour relationship of methyl eugenol and its derivatives, focusing on the chemical transformation of the double bond to hydroxyether derivatives in a controlled manner. Two derivatives 2-(4-ethyl- 3-methoxybenzyl)oxirane (68.8% yield) and 1-(3,4-dimethoxyphenyl)-3-ethoxypropan-2-ol (63.58% yield), were synthesized from methyl eugenol. This research found that the odour characteristic of 2-(4-ethyl-3-methoxybenzyl)oxirane[floral, fresh, slight lime and sweet]compounds, is clearly different from the odours of the 1-(3,4-dimethoxyphenyl)-3-ethoxypropan-2-ol [Glue-like, pungent, and Caramel-like]. It is evident from our observations that double bond substitution and functional alteration of the methyl eugenol modifies the perceived odour of methyl eugenol derivative. Thus, structural modification overall led to an increase in odour potency. Keywords: Fragrance, Methly-Eugenol, Ether, Olfactory characteristic, Epoxidation.

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Rizk, Sameh, Ismail M. Awheda, and Fathi A. Smida. "Synthesis and DFT Study of Newly Schiff Base and Fused Heterocyclic Compounds as Antibacterial Agent." JOURNAL OF ADVANCES IN CHEMISTRY 16 (November 7, 2019): 5395–403. http://dx.doi.org/10.24297/jac.v16i0.8499.

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Treatment of 2,3-di-(4-chlorophenyl) oxirane-2,3-dicarbonitriles(1) with nitrogen nucleophiles, e.g. N2H4, NH2OH afforded pyrazole 2, 1.2oxazole 3 derivatives respectively The 3-amino pyrazole-4-one derivatives 2 can be used as a key starting materials to synthesize some important Schiff base 4 and fused heterocyclic compounds e.g. Imidazolo-[4,5-c]pyrazole 5, Pyrazolo[3,4-e]1,2,4-triazine 6, pyrazol[1,2-a] 1,3,5-triazine 7, 8 and 9. The electromeric effect of the halogen atom in the aryl moieties can be controlled upon the rate of reaction and the yield of the product. The structures of synthesized new compounds were characterized by spectral data and screened for their antimicrobial activities against various bacteria and fungi strains. The heterocyclic compounds 7, 8 and 9 that contained bridgehead nitrogen gave an excellent result.

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Sihag, Sheetal, Parvesh Devi, Rajvir Singh, and Sushila Singh. "Synthesis, Characterization and Bioactivity of Propranolol and it's Derivatives." Asian Journal of Organic & Medicinal Chemistry 7, no. 1 (2022): 92–98. http://dx.doi.org/10.14233/ajomc.2022.ajomc-p368.

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Herein, the conventional method used for β-blocker synthesis is initiated by refluxing biphenyl-2-ol (1) with an epoxy ring (2) in the presence of K2CO3 to obtain 2-[(biphenyl-2-yloxy)methyl]oxirane (3). Compound (3) was then reacted with 99% isopropylamine (4) and various substituted phenols (6a-i) to form 1-(biphenyl-2-yloxy)-3-(propan-2-ylamino)propan-2-ol (5) and 1-(2,6-dimethyl-/4-methoxy- /4-chloro-3-hydroxy-/2,6-dimethoxy-/3,4-dimethyl-/4-amine-/4-bromo/3,4-dinitro-/2,4- dihydroxyphenoxy)-3-(biphenyl-2-yloxy)-propan-2-ols (7a-i), respectively. The synthesized compounds were analyzed by 1H NMR and FTIR spectroscopy to determine their structure and also evaluated for their antifungal activity against Rhizoctonia solani and Aspergillus niger using the food poison technique. From the activity data, it was found that compound 1-(biphenyl-2-yloxy)-3-(propan- 2-ylamino)-propan-2-ol (5) was most active against both the fungi Rhizoctonia solani and Aspergillus niger. The antibacterial activity was also determined against Bacillus species by zone of inhibition method. The compounds (5, 7a-i) were also evaluated for its herbicidal activity.

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Mammadaliyeva, F. "THERMOSTABLE EPOXIDE COMPOSITION BASED ON AROMATIC DIAMIDODISULFOIMIDE RESIN." ASJ 1, no. 51 (August 11, 2021): 35–40. http://dx.doi.org/10.31618/asj.2707-9864.2021.1.50.114.

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New epoxide oligomers have been obtained by the interaction of p-phenylenediaminediamidodisulfoimide with a large excess of epichlorohydrin in the presence of triethylbenzylammonium chloride. The synthesized epoxide oligomers are a viscous product of dark brown color, well soluble in aprotic solvents (DMFA, DMSO), as well as in acetone and dioxane. These cooligomers include hydroxynaphthylene and phenylenediimine structural fragments possessing solubility, meltability and high reactivity in the reactions with the oxirane ring of epoxide compounds in composition of macromolecules. The cooligomer of m-phenylenediamine with α-naphthol was used for curing of diamidodisulfoimide resin.

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ANDILA, PUTRI SRI, I. PUTU AGUS HENDRA, PUTRI KESUMA WARDANI, I. GEDE TIRTA, SUTOMO SUTOMO, and DEDEN FARDENAN. "The phytochemistry of Cymbopogon winterianus essential oil from Lombok Island, Indonesia and its antifungal activity against phytopathogenic fungi." Nusantara Bioscience 10, no. 4 (September 24, 2018): 232–39. http://dx.doi.org/10.13057/nusbiosci/n100406.

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Andila PS, Hendra IPA, Wardani PK, Tirta IG, Sutomo, Fardenan D. 2018. The phytochemistry of Cymbopogon winterianus essential oil from Lombok Island, Indonesia and its antifungal activity against phytopathogenic fungi. Nusantara Bioscience 10: 232-239. Cymbopogon winterianus Jowitt ex Bor [Sereh Wangi] is a plant producing essential oil that has been extensively used in perfumery, mosquito repellent, medicinal, and cosmetic industry. In Indonesia, the accession of C. winterianus plant had been collected from natural forest in Sembalun, Lombok, West Nusa Tenggara (NTB) Province. However, the phytochemical properties and its biological potential of this accession have never been reported. The aim of this study was to determine the phytochemical content of essential oil of C. winterianus from Lombok and to explore its potential as a bioantifungal against several phytopathogen fungi. The essential oils were extracted from fresh stem and leaf of C. winterianus by hydrodistillation. The chemical composition of them was determined by chromatography-mass spectrometry (GC-MS). A total of 26 and 20 compounds were obtained from the stem and leaf oil with the dominant compounds of essential oil in stem were Torreyol (17.89%), Oxirane, octyl- (15.84%), (-)-Isopulegol (14.44%), Isopulegol 2 (12.18%), and Geranyl Acetate (5.89%) while in leaf were (-)-Isopulegol (22.69%), Oxirane, octyl- (16.64%), Cyclohexanol, 5-methyl-2-(1-methylethenyl)- (14.21%), "KW3 AUS Epiglobulol” (9.47%), and Cyclohexene, 1-methyl-4-(1-methylethenyl)- (7.14%). The presence of these contents as dominant chemical compounds in S. winterianus was reported for the first time. The highest content of oils was identified as monoterpene (38.01% and 45.78% in stem and leaf oil) and sesquiterpene ( 27.67% and 17.78 % in stem and Leaf oil). The biological study showed that leaf essential of C. winterianus expressed positive antifungal activity against Fusarium solani, Aspergillus niger, dan Cladosporium sp.

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Raifeld, Yuri E., Anotonina A. Nikitenko, and Boris M. Arshava. "Compounds of (i-PrO)3 TiX as novel reagents for regioselective oxirane ring opening." Tetrahedron: Asymmetry 2, no. 11 (January 1991): 1083–84. http://dx.doi.org/10.1016/s0957-4166(00)82001-7.

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RAIFELD, YU E., A. A. NIKITENKO, and B. M. ARSHAVA. "ChemInform Abstract: Compounds of (iPrO)3TiX as Novel Reagents for Regioselective Oxirane Ring Opening." ChemInform 23, no. 10 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199210063.

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38

Liboska, Radek, Milena Masojídková, and Ivan Rosenberg. "Carbocyclic Phosphonate-Based Nucleotide Analogs Related to PMEA. I. Racemic trans-Configured Derivatives." Collection of Czechoslovak Chemical Communications 61, no. 2 (1996): 313–32. http://dx.doi.org/10.1135/cccc19960313.

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Racemic trans-N-(2-phosphonomethoxycycloalkyl) derivatives of heterocyclic bases, a novel type of nucleotide analogs related to 9-(2-phosphonomethoxyethyl)adenine (PMEA), are reported. The synthesis of fully protected adenine- (5), hypoxanthine- (7), guanine- (11), thymine- (13), uracil- (16) and cytosine-containing (18) carbocyclic nucleotide analogs is based on the reaction of trans-2-hydroxycycloalkyl derivatives of N-protected nucleobases (2, 10, 12, 14, 17) with diisopropyl tosyloxymethanephosphonate. Deprotection of these compounds afforded the title nucleotide analogs. The starting nucleoside derivatives have been prepared via nucleophilic oxirane ring opening of cycloalkene oxides with various protected or free nucleobases.

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39

Mousaa, Issa, and Hamdi Radi. "New corrosion inhibitors based on epoxidized natural rubber for coating protection of metals under UV irradiation." Anti-Corrosion Methods and Materials 64, no. 4 (June 5, 2017): 389–96. http://dx.doi.org/10.1108/acmm-01-2016-1628.

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Purpose In the present work, under severe conditions of an inert atmosphere and high temperature, epoxidized natural rubber (ENR) with 25 per cent epoxidation level reacts with different aliphatic amine compounds such as ethyl amine (EA), propyl amine (PA) and butyl amine (BA) to prepare ENR/EA, ENR/PA, ENR/BA compounds as, respectively. The produced compounds were characterized by Fourier transform infrared spectroscopy and oxirane oxygen content determination. Different concentrations of the produced compounds were added to epoxy and urethane acrylate coating formulations to evaluate them as corrosion inhibitors for mild steel under UV irradiation. Corrosion resistance tests and weight loss measurements of the coated steel panels were made. It was found that coating formulations containing the prepared ENR/EA compound could protect metal surface from corrosion, and corrosion inhibitors efficiency of the prepared compounds were arranged as follows: ENR/EA > ENR/PA > ENR/BA. The optimum concentrations for all inhibitors which give the best inhibition efficiency for corrosion are 0.4-0.6 phr. Design/methodology/approach Corrosion scratch tests were carried out according to ASTM D 1,654-92 (2000). The weight loss of coated steel was measured according to ASTM D 2,688-94 (1999). The measurement of film hardness was carried out with a Wolff–Wilborn pencil hardness tester according to ASTM D 3,363 (2000). Findings It was found that coating formulations containing the prepared ENR/EA compound could protect metal surface from corrosion and corrosion inhibitors efficiency of the prepared compounds were arranged as follows: ENR/EA > ENR/PA > ENR/BA. The optimum concentrations for all inhibitors are 0.4-0.6 g/100g coating. Originality/value A highly efficient and economically corrosion inhibitors for mild steel were prepared from ENR and series of aliphatic amines.

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Janeba, Zlatko, Antonín Holý, and Milena Masojídková. "Transformation of 8-[(2-Hydroxyalkyl)sulfanyl]adenines to 6-Amino-7H-purin-8(9H)-one Derivatives." Collection of Czechoslovak Chemical Communications 66, no. 9 (2001): 1393–406. http://dx.doi.org/10.1135/cccc20011393.

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Alkylation of 6-amino-7H-purin-8(9H)-thione (8-sulfanyladenine, 1) with one equivalent of (R)-[(trityloxy)methyl]oxirane gave its S-alkyl derivative 2, which was converted to the 6-amino-7H-purin-8(9H)-one (3), while alkylation of 1 with two equivalents of (S)-[(trityloxy)methyl]oxirane afforded a mixture of N3,S-dialkylated product 4a, N9-monoalkyl and N7,N9-dialkyl derivatives of 6-amino-7H-purin-8(9H)-one, 5a and 6a, respectively. This approach can be used for rapid and easy transformation of 8-[(2-hydroxyalkyl)sulfanyl]adenines to the derivatives of 6-amino-7H-purin-8(9H)-one (8-hydroxyadenine) using NaH or Cs2CO3 in DMF. The course of the S→O transformation strictly depends on the character of the starting compounds and on the reaction conditions. N9-Alkyl-8-[(2-hydroxyalkyl)sulfanyl]adenines 10, 12, 14 and 17 were rapidly converted to the corresponding 6-amino-7H-purin-8(9H)-one derivatives 11, 13, 11 and 18, respectively. N9-Unsubstituted 2 reacts slowly, and N3-alkyl derivative 4a is stable under the same reaction conditions. The described transformation does not occur when the hydroxy group in 8-[(2-hydroxyalkyl)sulfanyl]adenine derivative 15 is protected. The reaction using NaH proceeds more rapidly than that using Cs2CO3.

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Krečmerová, Marcela, Antonín Holý, and Milena Masojídková. "Pyrimidine Acyclic Nucleotide Analogues with Aromatic Substituents in C-5 Position." Collection of Czechoslovak Chemical Communications 72, no. 7 (2007): 927–51. http://dx.doi.org/10.1135/cccc20070927.

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NH2-protected 5-phenylcytosine and its derivatives 2a-2d were treated with (2S)-2-[(trityloxy)methyl]oxirane (3) followed by etherification with diisopropyl [(tosyloxy)methyl]phosphonate (5) in the presence of sodium hydride. The intermediary phosphonate esters 6 were debenzoylated and subsequently transformed to free phosphonic acids, i.e. (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-phenylcytosine (5-phenyl-HPMPC) derivatives (8a-8d) by the action of bromotrimethylsilane and subsequent hydrolysis. Deamination of these compounds with 3-methylbutyl nitrite afforded corresponding (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-phenyluracil (5-phenyl-HPMPU) derivatives (9a-9d). R-Enantiomers 14 and 15 were prepared analogously starting from (2R)-2-[(trityloxy)methyl]oxirane. 5-Benzyl-, 5-[(1-naphthyl)methyl]- and 5-[(2-naphthyl)methyl]HPMPU (24a-24c) and -HPMPC (25a-25c) were synthesized from appropriate 5-arylmethyl-4-methoxypyrimidin-2(1H)-ones similarly as described for 5-phenyl derivatives. Antiviral activity was found for (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-phenyluracil (9a) (HSV-1 and HSV-2) and (R)-1-[3-hydroxy2-(phosphonomethoxy)propyl]-5-phenylcytosine (14) (cytomegalovirus and varicella-zoster virus), both tested in cell cultures. Some of the 5-phenyluracil derivatives possessed inhibitory activity against thymidine phosphorylase from SD-lymphoma.

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42

Meng, Yudong, Francesco Taddeo, Adriana Freites Aguilera, Xiaoshuang Cai, Vincenzo Russo, Pasi Tolvanen, and Sébastien Leveneur. "The Lord of the Chemical Rings: Catalytic Synthesis of Important Industrial Epoxide Compounds." Catalysts 11, no. 7 (June 24, 2021): 765. http://dx.doi.org/10.3390/catal11070765.

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The epoxidized group, also known as the oxirane group, can be considered as one of the most crucial rings in chemistry. Due to the high ring strain and the polarization of the C–O bond in this three-membered ring, several reactions can be carried out. One can see such a functional group as a crucial intermediate in fuels, polymers, materials, fine chemistry, etc. Literature covering the topic of epoxidation, including the catalytic aspect, is vast. No review articles have been written on the catalytic synthesis of short size, intermediate and macro-molecules to the best of our knowledge. To fill this gap, this manuscript reviews the main catalytic findings for the production of ethylene and propylene oxides, epichlorohydrin and epoxidized vegetable oil. We have selected these three epoxidized molecules because they are the most studied and produced. The following catalytic systems will be considered: homogeneous, heterogeneous and enzymatic catalysis.

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43

Ružena, Čižmáriková, Habala Ladislav, Valentová Jindra, and Šmátralová Dana. "Syntéza a HPLC enantioseparácia nových derivátov 3-alkoxy-4-hydroxyfenylalkanónov typu potenciálnych α/β-blokátorov." Česká a slovenská farmacie 70, no. 1 (2021): 51–58. http://dx.doi.org/10.5817/csf2021-2-51.

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The present paper reports the synthesis of a series of seven compounds with a hetero aminopropanol chain. The compounds were prepared by the conversion of 3-alkoxy-4-hydroxyphenyl alkanones with 2-chloromethyl oxirane and subsequent reaction of the products with heterocyclic amines (pyrrolidine, azepane, 4-methylpiperazine and 2-methoxyphenyl piperazine). The target compounds were synthesized in the form of racemates. The purity of the products was confirmed by thin layer chromatography and their IR, UV-VIS and 1H-NMR spectra were recorded. Enantioseparation of the racemic products was accomplished by HPLC on a Chiralpak AD chiral chromatographic column with tris(3,5-dimethylphenyl)carbamate as the chiral selector. The efficiency of enantioseparation was determined in relation to the composition of the mobile phase (hexane : ethanol : methanol : ethylethanamine) and to the structure of the prepared compounds. Baseline separation was achieved with all compounds using mobile phases A (78 : 11 : 11 : 0,1 v/v/v/v) and B (80 : 10 : 10 : 0,1 v/v/v/v), with selectivity factor ranging from 1.07 to 1.42 and resolution from 0.76 to 5.47. The mobile phase containing a higher amount of hexane did not allow for successful enantioseparation of the piperazine derivatives.

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44

Zakaria, M. A., K. F. Fridiasari, A. F. Ni’mah, A. Macorowalie, Y. Santoso, O. A. Saputra, M. Bagaskara, R. E. Mustofa, E. Pramono, and C. Purnawan. "Thermal properties of hybrid membrane-based PVDF modified with cellulose and silylated cellulose." Journal of Physics: Conference Series 2190, no. 1 (March 1, 2022): 012017. http://dx.doi.org/10.1088/1742-6596/2190/1/012017.

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Abstract Cellulose extracted from Oil Palm Empty Fruit Bunches has been successfully modified by amino-based and oxirane-based silylating compounds. The modified and unmodified cellulose was incorporated into polyvinylidene fluoride (PVDF) membranes through the phase-inversion. The resulted membranes were further analyzed using Differential Scanning Calorimetry (DSC) to distinguish the thermal properties, including melting temperature and crystallinity of the membranes. Moreover, the water uptake properties of the membranes were discussed in this study. The melting temperature of each membrane is not significantly different. However, PVDF/CellGPTMS has better thermal properties compared to others. The presence of cellulose and its modified product within PVDF membranes improved the crystallinity of the membranes.

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Jankowski, Christopher K., Etienne Dako, Antoun Bou Laouz, Marcel Delaforge, Jocelyn R. J. Paré, and Jacqueline M. R. Belanger. "On the prenylation of some indolic and imidazolic bases by oxirane auxiliaries under thermal and microwave conditions." Spectroscopy 21, no. 5-6 (2007): 293–303. http://dx.doi.org/10.1155/2007/153149.

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The analogue of isoprene, 2-methyl-2-vinyloxirane, a versatile isoprene auxiliary, was reacted with some indolic and imidazolic bases, to add one or more isoprene unit(s), to these compounds. This prenylation was realised by using thermal and microwave assisted pathways, via the nucleophilic opening of the epoxide ring. The biological importance of the prenylated derivatives resides in their potential application as drugs. The aminoacids and small protein biomarkers are obtained from simple epoxide opening reactions. All new compounds were characterised by high resolution NMR, mass spectroscopy, GC-MS and LC-MS as well.

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Ullah, Hafeez, Khairun Azizi Mohd Azizli, Zakaria B. Man, Mokhtar B. Che Ismail, Siaf Ur Rehman, and Muhammed Irfan Khan. "Efficient Entrapment of Oxirane Ring Containing Compounds in Thermally Stable Poly(urea-formaldehyde) Polymer Shell Wall." Polymer Science, Series B 60, no. 1 (January 2018): 20–34. http://dx.doi.org/10.1134/s1560090418010141.

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Kizhnyaev, V. N., F. A. Pokatilov, T. N. Baginova, R. G. Zhitov, and A. G. Proidakov. "Influence of the structure of oxirane-containing compounds on curing of poly-N-methyl-5-vinyltetrazole." Russian Journal of Applied Chemistry 89, no. 7 (July 2016): 1137–44. http://dx.doi.org/10.1134/s1070427216070144.

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48

Shaaban, Mohamed, Mohamed A. Ghani, and Khaled A. Shaaban. "Zahramycins A-B, Two New Steroids from the Coral Sarcophyton trocheliophorum." Zeitschrift für Naturforschung B 68, no. 8 (August 1, 2013): 939–45. http://dx.doi.org/10.5560/znb.2013-3131.

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Two new poly-hydroxy steroids, zahramycins A (1) and B (2), have been isolated from the polar fraction of the extract of the coral Sarcophyton trocheliophorum. Compound 1 was confirmed to bear an oxirane ring at C-5 and C-6, while 2 has a keto-hydroxy sterol structure. The known DNA primary metabolites uracil, thymine, adenine, uridine, 2´-deoxyuridine, and thymidine were also isolated and identified. Structures of the new sterols 1 and 2 were confirmed by NMR ( 1H, 13C, 1H-1H COSY, HMQC, HMBC, and NOESY) spectroscopy, mass spectrometry (EI, ESI, and HRMS), and by comparison with related structures. The antimicrobial and cytotoxic activities of compounds 1 and 2 along with that of the coral extract were also determined. Zahramycin B (2) showed high (15 mm) and moderate (12 mm) antibacterial activity against Staphylococcus aureus and Bacillus subtilis, and fungus Pythium ultimum (12 mm), while zahramycin A (1) and the crude extract of Sarcophyton trocheliophorum were inactive. Both steroids and the crude extract of Sarcophyton trocheliophorum showed no cytotoxicity.

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Janssen, D. B., M. Majerić-Elenkov, G. Hasnaoui, B. Hauer, and J. H. Lutje Spelberg. "Enantioselective formation and ring-opening of epoxides catalysed by halohydrin dehalogenases." Biochemical Society Transactions 34, no. 2 (March 20, 2006): 291–95. http://dx.doi.org/10.1042/bst0340291.

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Halohydrin dehalogenases catalyse the conversion of vicinal halohydrins into their corresponding epoxides, while releasing halide ions. They can be found in several bacteria that use halogenated alcohols or compounds that are degraded via halohydrins as a carbon source for growth. Biochemical and structural studies have shown that halohydrin dehalogenases are evolutionarily and mechanistically related to enzymes of the SDR (short-chain dehydrogenase/reductase) superfamily. In the reverse reaction, which is epoxide-ring opening, different nucleophiles can be accepted, including azide, nitrite and cyanide. This remarkable catalytic promiscuity allows the enzymatic production of a broad range of β-substituted alcohols from epoxides. In these oxirane-ring-opening reactions, the halohydrin dehalogenase from Agrobacterium radiobacter displays high enantioselectivity, making it possible to use the enzyme for the preparation of enantiopure building blocks for fine chemicals.

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Kavipriya, K., and M. Chandra. "FTIR and GCMS Analysis of Bioactive Phytocompounds in Methonalic Leaf Extract of Cassia Alata." Biomedical and Pharmacology Journal 11, no. 1 (March 25, 2018): 141–47. http://dx.doi.org/10.13005/bpj/1355.

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The methanolic extract of plant Cassia alata was prepared by using soxhlet apparatus. FTIR and GCMS analysis were done to this plant extract to find out the bioactive phytocompounds. The FTIR results of this plant extract showed 21 peaks indicate the presence of the bioactive compounds such as sulfates, sulfonamides, sulfones, sulfonyl chlorides, sulfates, sulfonamides, alkanes, aromatic, aromatic, alkenes, ester, alkenes, ketenes, isocyanates, isothiocyanates, acetylene, nitrile, phosphine, phosphine, aldehyde, alkane, amide, alcohol and alcohol. The GCMS results showed 13 peaks. The retention time (RT) of all these thirteen peaks indicate the presence of functional group such as 1-Butanol, 3-methyl-1,6-Anhydro-.beta.-D-glucopyranose (levoglucosan), 3-O-Methyl-d-glucose, Oxirane, 10-Methyl-E-11-tridecen-1-ol propionate, l-(+)-Ascorbic acid 2,6-dihexadecanoate, (R)-(-)-14-Methyl-8-hexadecyn-1-ol, Oleic Acid , Vitamin E acetate and 1,2-Bis(trimethylsilyl) benzene.

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Journal articles on the topic 'Oxirane compounds'

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