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Journal articles on the topic 'Isomeric oximes'

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Published: 5 June 2025

Last updated: 15 July 2025

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1

Vystrčil, Alois, Václav Křeček, Miloš Buděšínský, and Jiří Protiva. "Isomeric oximes of 30-norlupan-20-one and its derivatives." Collection of Czechoslovak Chemical Communications 51, no. 3 (1986): 581–92. http://dx.doi.org/10.1135/cccc19860581.

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30-Norlupan-20-one (Ib) and its derivatives IIb-Vb were converted into 5 : 1-10 :1 mixtures of relatively stable E and Z oximes Ic,d-Vc,d. Beckmann rearrangement of the oxime mixtures (as obtained from the oximation) afforded isomeric amides VIII-XII and XIII-XVI in the ratios 3.5 : 1 to 5 : 1. Oximes Vc,d with the E-ring bridged by a lactone grouping, react with difficulty and the rearrangement was proved only for the Z-isomer Vd.

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2

Koshchii, I., O. Vasilkevich, and Yu. Klimko. "BECKMAN REACTION OF KETOXIMES OF THE TRICYCLO[5.2.1.02,6]DECAN SERIES WITH THIONYL CHLORIDE." Sciences of Europe, no. 145 (July 26, 2024): 15–20. https://doi.org/10.5281/zenodo.12909376.

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As a result of the Beckmann reaction, the oximes tricyclo[5.2.1.02,6]decan-9-one, tricyclo[5.2.1.02,6]dec-3-en-9-one and tricyclo[5.2.1.02,6]dec-4-ene -9-one with thionyl chloride forms transmutation products - lactams and fragmentation products - unsaturated nitriles and isomeric chloronitriles.

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3

Tyukhtenko, Sergiy, Michael Hilton, and Nikolay Gerasimchuk. "Classic Isomeric 1,2- and 2,1-nitrosonaphthols are Oximes in Solid State and Solutions." Current Inorganic Chemistry 5, no. 2 (2015): 120–36. http://dx.doi.org/10.2174/187794410502150702104914.

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4

Gorrod, J. W., and M. Christou. "MetabolicN-Hydroxylation of substituted acetophenone ixnines. I. Evidence for formation of isomeric oximes." Xenobiotica 16, no. 6 (1986): 575–85. http://dx.doi.org/10.3109/00498258609043546.

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5

Rauret, G., and J. S. Mestres. "Analytical properties of the isomeric oximes derivated from the 2-amino-5-chlorobenzophenone." Microchemical Journal 31, no. 1 (1985): 107–12. http://dx.doi.org/10.1016/0026-265x(85)90016-5.

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6

Meadows, Mikala, Lei Yang, Cody Turner, Mikhail Berezin, Sergiy Tyukhtenko, and Nikolay Gerasimchuk. "Synthesis and Characterization of Pt(II) and Pd(II) Complexes with Planar Aromatic Oximes." Inorganics 11, no. 3 (2023): 116. http://dx.doi.org/10.3390/inorganics11030116.

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A series of four Werner-type complexes of Pd(II) and Pt(II) with planar, isomeric conjugated aromatic naphtoquinone oximes were synthesized for the first time. These ligands were 1-oxime-2-naphtoquinone (HL1) and 2-oxime-1-napthoquinone (HL2). Compounds were characterized using thermal analysis, spectroscopic methods, and X-ray analysis. TG/DSC data were collected for pure starting organic ligands, their complexes, and indicated vigorous exothermic decomposition with at ~155 °C for starting HL and ~350 °C for transition metal complexes. Crystal structures for two Pt compounds with 2-oxime-1-quinone were determined and revealed the formation of the cis-geometry complexes and incorporation of molecules of stoichiometric solvents in the lattice: acetonitrile and nitrobenzene. Both solvents of crystallization displayed attractive interactions between their C-H groups and the oxygen atoms of the nitroso groups in complexes, leading to short distances in those fragments. Despite the presence of solvents of inclusion, the overall structure motifs in both compounds represent 1D columnar coordination polymer, in which the PtL2 units are held together via metallophilic interactions, thereby forming ‘Pt-wires’. The Hirshfield surface analysis was performed for both crystallographically characterized complexes. The results showed intermolecular π–π stacking and Pt–Pt interactions among the planar units of both complexes. In addition, the analysis also verified the presence of hydrogen bonding interactions between the platinum unit and solvent molecules. Solid bulk powdery samples of both PtL12 and PtL22 demonstrated pronounced photoluminescence in the near infrared region of spectrum at ~980 nm, being excited in the range of 750–800 nm. The NIR emission was observed only for Pt-complexes and not for pure starting organic ligands or Pd-complexes. Additionally, synthesized Pt-naphtoquinone oximes do not show luminescence in solutions, which suggests the importance of a 1D ‘metal wire’ structure for this process.

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7

Argyle, Victoria J., Laura M. Woods, Marina Roxburgh, and Lyall R. Hanton. "Triflate anion and ligand influences in silver(i) coordination polymers of four isomeric dipyridyl ketone oximes." CrystEngComm 15, no. 1 (2013): 120–34. http://dx.doi.org/10.1039/c2ce26449h.

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8

Boeyens, Jan C. A., Leanne M. Cook, Tak-ho Ngoi, and David H. Reid. "Crystal structures of two isomeric oximes. (EE)-2-methyl-3-phenyl-3-thiocyanatopropenaldoxime and (Z)-5-methyl-6-phenyl-1,3-thiazin-2-one oxime." Journal of Chemical Crystallography 26, no. 3 (1996): 215–18. http://dx.doi.org/10.1007/bf01673673.

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9

Lapčík, Oldřich, Richard Hampl, Martin Hill, et al. "Radioimmunological and Chromatographic Properties of Tyrosine Methyl Ester Conjugates with Stereoisomeric Steroid Carboxy Derivatives." Collection of Czechoslovak Chemical Communications 61, no. 5 (1996): 799–807. http://dx.doi.org/10.1135/cccc19960799.

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Pure 3Z (syn) and 3E (anti) stereoisomers of testosterone 3-[O-(2-carboxyethyl)]oxime were synthesized, separated by HPLC or TLC, and used for preparation of tyrosine methyl ester (TME) conjugates by using mixed anhydride or carbodiimide-N-hydroxysuccinimide methods. While the latter method provided more than 96% of product with retained configuration, the mixed anhydride method yielded a mixture containing 26-40% of the opposite stereoisomer. The stereoisomers were used as model compounds, to which the other steroid TMEs and the corresponding radioiodinated products could be aligned according to their chromatographic properties. The TME conjugates of 3-(O-carboxymethyl)oximes of seven 4-en-3-oxo steroids were further prepared by carbodiimide-N-hydroxysuccinimide method. With exception of cortisol, the stereoisomeric (Z and E) radioiodinated TME conjugates could be separated by TLC. In addition, the conjugates with TME and consequently radioiodinated tracers were synthesized from hemisuccinates of cortisol and its 11α-isomer, via 11β- and 11α-hydroxy group. The radioiodinated conjugates were tested as radioligands with rabbit polyclonal antisera raised by using position-homologous conjugates of the respective steroid carboxy derivatives with bovine serum albumin as immunogens. With the exception of 11-deoxycorticosterone, the stereoisomeric Z and E radioiodinated TMEs did not differ in their binding properties. In the case of isomeric cortisol tracers conjugated through position 11 the antisera recognized only the sterically homologous radioligands, but the specificity of the system was poor.

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10

Celik, Hayati, Jiri Ludvik, and Petr Zuman. "Reduction of two isomeric oximes of aryl alkyl 1,2-diketones: Difference in products formed in polarography and controlled potential electrolysis." Electrochemistry Communications 8, no. 11 (2006): 1749–52. http://dx.doi.org/10.1016/j.elecom.2006.08.016.

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11

Szymanowski, J., E. Krzy⩅anowska, R. Cierpiszewski, and K. Prochaska. "Equilibrium and kinetics of copper extraction from acidic sulfate solutions with isomeric 1-(2′-hydroxy-5′-alkyl-phenyl)-1-alkanone (E)-oximes." Journal of Radioanalytical and Nuclear Chemistry Articles 150, no. 2 (1991): 335–50. http://dx.doi.org/10.1007/bf02035320.

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12

Polisel, Daniel A., Alexandre A. de Castro, Daiana T. Mancini, et al. "Slight difference in the isomeric oximes K206 and K203 makes huge difference for the reactivation of organophosphorus-inhibited AChE: Theoretical and experimental aspects." Chemico-Biological Interactions 309 (August 2019): 108671. http://dx.doi.org/10.1016/j.cbi.2019.05.037.

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13

Glaser, Rainer, and Andrew Streitwieser. "Ab initio study of the regiochemistry of dimetalated oximes. The importance of triple ions in isomeric lithium and sodium ion pairs of the acetaldoxime dianion." Journal of Organic Chemistry 54, no. 23 (1989): 5491–502. http://dx.doi.org/10.1021/jo00284a021.

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14

M¨ohrle, Hans, and Petra Arndt. "Hydroxylamin-Funktion als Nachbargruppe bei Dehydrierungen / Hydroxylamine Function as Neighboring Group with Dehydrogenations." Zeitschrift für Naturforschung B 60, no. 6 (2005): 688–700. http://dx.doi.org/10.1515/znb-2005-0614.

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The β -amino-hydroxylamines 5a - d are prepared of the α-amino-oximes 1a - d with boranedimethylsulfide. With mercury-EDTA, 5a - d react to (E/Z)-oxime-lactams 3a - d and benzaldoxime 7. Additionally 5b,c give the bicyclic amidine-N-oxides 8b,c, which slowly hydrolyze to the hydroxylamine-lactams 9b,c. These are easily oxidized to (E/Z)-3b,c. Postulated as intermediates in the mercury-assisted reduction of 5, the cyclic hydroxylamines 10a - d are available from the nitrones 4a - d with LiAlH4. From 10a - d with mercury-EDTA the same products are obtained as from 5a - d but without 7. Only the pyrrolidine 10a forms besides (E/Z)-3a the nitrone 4a. Thinlayer chromatography shows that the pure isomers of 3a - d in solution isomerize, contrary to the amine-oximes 1a - d. The configuration of the oxime-lactams depends on the manner of preparation. With mercury-EDTA, 1b,c yield 3b,c with retention of the configuration, while the oximation of phenacyl-lactams 13b,c give rise to (E/Z)-mixtures of 3b,c. The condensed imidazoles 12 result from the nitrones 4a - d and the dihydrooxadiazines 2a,d on treatment with hydrogen chloride.

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15

Richmond, William, Christian Tondre, Ewa Krzyzanowska, and Jan Szymanowski. "Metal extraction in micellar media: a comparison of copper complexation rates and ultrafiltration yields of two isomeric (E)-1-(2′-hydroxy-5′-alkylphenyl) 1-alkanone oximes." J. Chem. Soc., Faraday Trans. 91, no. 4 (1995): 657–63. http://dx.doi.org/10.1039/ft9959100657.

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16

Ali Bawa, Ramadan, and Aya Ramadan Swairi. "Synthesis of Some Alicyclic Oximes and Study of the Expected Conformational Isomerism." Academic Journal of Life Sciences, no. 512 (December 5, 2019): 116–20. http://dx.doi.org/10.32861/ajls.512.116.120.

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Five alicyclic oximes 1 – 5 have been readily synthesized in moderate to good yields. These oximes were obtained through a reaction between the hydroxylamine hydrochloride and a number of alicyclic ketones (cylobutanone, cyclopentanone, cyclohexanone, cycloheptanone and cyclooctanone) under mild reaction conditions. The spectroscopic data confirmed the formation of the first four oximes 1 – 4 as single conformational isomers. However, the cyclooctanone oxime 5 was obtained as a mixture of two conformational isomers with 81% for the major and only 19% for the minor isomer. Such finding could be an indication for the relationship between the increase of the ring size of the oxime and the raising possibility of the formation of conformational isomers as the flexibility of the ring increases.

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17

Bach, Robert D., Mark W. Tubergen та Russell C. Klix. "Lewis acid catalyzed rearrangements of structurally related α,β-unsaturated epoxy ketones and oximes. A complementary approach to the synthesis of isomeric 1,4-diketospiro[n,m] alkanes." Tetrahedron Letters 27, № 31 (1986): 3565–68. http://dx.doi.org/10.1016/s0040-4039(00)84850-9.

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18

Jirman, Josef, Antonín Lyčka, and Miroslav Ludwig. "13C and 15N NMR spectra of oximes prepared by nitrosation of activated methylene group." Collection of Czechoslovak Chemical Communications 55, no. 1 (1990): 136–46. http://dx.doi.org/10.1135/cccc19900136.

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15N and 13C NMR spectra have been measured of the compounds type XC(=NOH)Y, where X, Y = COCH3, CN, COOR, CONHR, and X +Y = C6H4(CO)2. The (E)-(Z) isomerism at the C=NOH bond has been studied by means of 15N labelling and stereospecific behaviour of the 2J(15N, 13C) coupling constants. The nitrosation of methyl cyanoacetate gives specifically the respective (E)-oxime, whereas that of acetoacetanilide gives the (Z)-isomer. The nitrosation of ethyl acetoacetate gives both (E)- and (Z)-oximes in a ratio of ca 1:10; the (E)-isomer is less stable and is transformed into the (Z)-isomer. The applicability of the 1J(13C, 13C) coupling constants and lanthanoid shift reagents to the study of (E)-(Z) isomerism of oximes with geminal carbonyl groups has also been verified. The 15N NMR chemical shifts of the oximes studied correlate with their respective pKa values measured in dimethyl sulfoxide according to the equation pKa = -0.11δ15N + 13.44.

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19

Bényei, Attila Csaba, and Laszlo Somogyi. "STEREOSTRUCTURE OF ISOMERIC (±)-1-THIOFLAVANONE 1-OXIDES." Phosphorus, Sulfur, and Silicon and the Related Elements 143, no. 1 (1998): 191–96. http://dx.doi.org/10.1080/10426509808045497.

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20

Argyle, Victoria J., Marina Roxburgh, and Lyall R. Hanton. "Use of the oxime–oximato binding mode to stabilise mixed valence copper iodide polymer networks using dipyridyl ketone oxime ligands." CrystEngComm 16, no. 28 (2014): 6345–53. http://dx.doi.org/10.1039/c3ce42481b.

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Coordination polymers formed from copper iodide and four isomeric dipyridyl ketone oxime ligands showed the importance the oxime–oximato bridge on the formation of mixed valence Cu(i)/Cu(ii) polymers.

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21

Bunce, Nigel J., H. Stewart McKinnon, Randy J. Schnurr, Sam R. Keum, and Erwin Buncel. "Fragmentation pathways in the mass spectra of isomeric phenylazoxypyridine-N-oxides." Canadian Journal of Chemistry 70, no. 4 (1992): 1028–32. http://dx.doi.org/10.1139/v92-137.

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The mass spectral fragmentation pathways of a series of phenylazoxypyridine-N-oxides have been studied under electron impact conditions using tandem mass spectrometry. Besides simple C—N cleavages, the azoxypyridine-N-oxides undergo deep-seated rearrangements directly from the molecular ion. In addition, the spectra are complicated by a purely chemical reduction of the N—O functionalities that occurs in the ion source prior to ionization.

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22

Craig, DC, RF Toia, and VJ Wacher. "X-Ray Crystal-Structure of 5-Acetoxymethyl-5-methyl-2-phenyl-1,3,2-dioxaphosphorinane 2-Oxide." Australian Journal of Chemistry 42, no. 6 (1989): 977. http://dx.doi.org/10.1071/ch9890977.

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The relative stereochemistries of the isomeric 5-acetoxymethyl-5-methyl-2-phenyl-1,3,2-dioxaphosphorinane 2-oxides have been assigned following single-crystal X-ray structural analysis of one of the isomers.

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23

Conde, Santiago, Carlos Corral, and Jaime Lissavetzky. "E- andZ-isomerism of 2-acetylthiophene oximes." Journal of Heterocyclic Chemistry 22, no. 2 (1985): 301–4. http://dx.doi.org/10.1002/jhet.5570220213.

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24

Chainikova, E. M., S. L. Khursan, and R. L. Safiullin. "Isomeric forms of arylnitroso oxides: Electronic spectra and reactivity." Kinetics and Catalysis 47, no. 4 (2006): 549–54. http://dx.doi.org/10.1134/s0023158406040100.

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25

Stoyanovich, F. M., V. N. Bulgakova, and M. M. Krayushkin. "Stable isomeric benzonitrile oxides derived from 6-chloro-2,4-dimethoxyaniline." Bulletin of the Academy of Sciences of the USSR Division of Chemical Science 40, no. 11 (1991): 2280–85. http://dx.doi.org/10.1007/bf00961052.

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26

Read, RW, and WP Norris. "The Nucleophilic Substitution Reactions of 5- and 7-Chloro-4,6-dinitrobenzofurazan 1-Oxide by Aromatic Amines." Australian Journal of Chemistry 38, no. 3 (1985): 435. http://dx.doi.org/10.1071/ch9850435.

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7-Chloro-4,6-dinitrobenzofurazan 1-oxide is a powerful electrophile which reacts with a variety of primary and secondary aromatic amines, even those with deactivating substituents , to give arylamino - benzofurazan oxides under mild conditions. Tertiary aromatic amines react through carbon to give aminoarylbenzofurazan oxides. During, or as a consequence of, the substitution reactions, tautomerism occurs to give in all but one example an equilibrium mixture of 5- and 7-substituted 4,6-dinitrobenzofurazan oxides in which the latter predominates. Thus 5-chloro-4,6-dinitrobenzofurazan 1-oxide and 7- chloro-4,6-dinitrobenzofurazan 1-oxide both react with aniline to yield the same isomeric mixture of products: 4,6-dinitro-7- phenylaminobenzofurazan oxide (predominantly 1-oxide) (major) and 4,6- dinitro-5-phenylaminobenzofurazan 1-oxide (minor). The 5- and 7- phenylamino 4,6-dinitrobenzofurazans were prepared to assist in structural assignment of the N-oxides.

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27

Nielsen, Jacob H., Carl Erik Olsen, Christina Duedahl, and Leif H. Skibsted. "Isolation and quantification of cholesterol oxides in dairy products by selected ion monitoring mass spectrometry." Journal of Dairy Research 62, no. 1 (1995): 101–13. http://dx.doi.org/10.1017/s0022029900033719.

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SUMMARYA method for isolation, detection and quantification of cholesterol oxidation products based on solid phase extraction in combination with preparative HPLC and gas chromatography–mass spectrometry selected ion monitoring has been developed for dairy products. The isolation procedure had a high recovery and artifact formation was minimal, as shown by isotope labelling. The limits of detection ranged from 0.3 to 35 pg/μl of the isomeric forms of 7-hydroxycholesterol, 20α-hydroxycholesterol, the isomeric forms of cholesterol-5,6-epoxides, cholestanetriol, 25-hydroxycholesterol and 7-ketocholesterol corresponding to a limit of quantification of 2–6 ng oxysterol/g lipid in the dairy product, depending on the nature of the cholesterol oxidation product.

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28

Kim, Ik-Hwan, Kyeong Hyeon Kim, Hyunhee Jo, Burm-Jong Lee, Dong-Eun Kim, and Hoon-Kyu Shin. "Synthesis and OLED Characteristics of Isomeric Phosphine Oxides Containing Naphthoxazole Moiety." Journal of Nanoscience and Nanotechnology 17, no. 5 (2017): 3298–303. http://dx.doi.org/10.1166/jnn.2017.14070.

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29

Cignitti, Maurizio, Laura Soccorsi, Franco Gatta, and Marina Cotta-Ramusino. "Isomeric methoxypyridine-1-oxides and 1-methoxypyridones: Electronic spectra and structure." Spectrochimica Acta Part A: Molecular Spectroscopy 41, no. 11 (1985): 1287–94. http://dx.doi.org/10.1016/0584-8539(85)80236-1.

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30

STOYANOVICH, F. M., V. N. BULGAKOVA, and M. M. KRAYUSHKIN. "ChemInform Abstract: Stable Isomeric Benzonitrile Oxides from 6-Chloro-2,4-dimethoxyaniline." ChemInform 24, no. 52 (2010): no. http://dx.doi.org/10.1002/chin.199352143.

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31

Shamblin, Jacob, Mikhail Feygenson, Joerg Neuefeind, et al. "Probing disorder in isometric pyrochlore and related complex oxides." Nature Materials 15, no. 5 (2016): 507–11. http://dx.doi.org/10.1038/nmat4581.

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32

Chaudhary, Pranita A., Mrudula Wadekar, V. B. Adsul, and V. B. Jadhav. "A New Perspective of Ligands and their Metal Chelates for Anthelmintic Activity." YMER Digital 21, no. 06 (2022): 732–46. http://dx.doi.org/10.37896/ymer21.06/74.

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Metal chelates of isomeric 1,2-Naphthoquinone mono oxime were prepared with Oxo metals like ammonium molybdate and sodium tungstate in a methanolic solution. The chemical composition was established as ML2. The structural investigations of the chelates were carried out by analytical tools such as TGA, XRD, SEM and elemental analysis. Further investigations were performed by spectral methods such as IR, Far IR, UV-VIS, 1H NMR and 13C NMR. The ligands and their metal chelates of ammonium molybdate [(NH4)6MoO24. H2O] and sodium tungstate [Na2WO4] exhibited significant biological activity. Therefore, the anthelmintic activity was performed. The results are indicative of the medicinal importance to the human health fare. Key words: 1,2-Naphthoquinone(NQ)-1- oxime, 1,2-Naphthoquinone(NQ)-2- oxime, Ammonium molybdate, Sodium tungstate, Anthelmintic activity

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33

Michaud, Dennis P., Nashaat T. Nashed, and Donald M. Jerina. "Stereoselective synthesis and solvolytic behavior of the isomeric 7-dehydrocholesterol 5,6-oxides." Journal of Organic Chemistry 50, no. 11 (1985): 1835–40. http://dx.doi.org/10.1021/jo00211a009.

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34

Lutz, Andrea, Peter Winterhalter, and Peter Schreier. "Isolation of a glucosidic precursor of isomeric marmelo oxides from quince fruit." Tetrahedron Letters 32, no. 42 (1991): 5943–44. http://dx.doi.org/10.1016/s0040-4039(00)79432-9.

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35

Brash, Alan R., William E. Boeglin, Donald F. Stec, Markus Voehler, Claus Schneider, and Jin K. Cha. "Isolation and Characterization of Two Geometric Allene Oxide Isomers Synthesized from 9S-Hydroperoxylinoleic Acid by Cytochrome P450 CYP74C3." Journal of Biological Chemistry 288, no. 29 (2013): 20797–806. http://dx.doi.org/10.1074/jbc.m113.482521.

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Specialized cytochromes P450 or catalase-related hemoproteins transform fatty acid hydroperoxides to allene oxides, highly reactive epoxides leading to cyclopentenones and other products. The stereochemistry of the natural allene oxides is incompletely defined, as are the structural features required for their cyclization. We investigated the transformation of 9S-hydroperoxylinoleic acid with the allene oxide synthase CYP74C3, a reported reaction that unexpectedly produces an allene oxide-derived cyclopentenone. Using biphasic reaction conditions at 0 °C, we isolated the initial products and separated two allene oxide isomers by HPLC at −15 °C. One matched previously described allene oxides in its UV spectrum (λmax 236 nm) and NMR spectrum (defining a 9,10-epoxy-octadec-10,12Z-dienoate). The second was a novel stereoisomer (UV λmax 239 nm) with distinctive NMR chemical shifts. Comparison of NOE interactions of the epoxy proton at C9 in the two allene oxides (and the equivalent NOE experiment in 12,13-epoxy allene oxides) allowed assignment at the isomeric C10 epoxy-ene carbon as Z in the new isomer and the E configuration in all previously characterized allene oxides. The novel 10Z isomer spontaneously formed a cis-cyclopentenone at room temperature in hexane. These results explain the origin of the cyclopentenone, provide insights into the mechanisms of allene oxide cyclization, and define the double bond geometry in naturally occurring allene oxides.

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36

Serra, Stefano, Davide De Simeis, and Sara Papili. "A Practical Laboratory-Scale Synthesis of All Eight Stereoisomeric Forms of Terpene Linalool Oxide." Chemistry 3, no. 4 (2021): 1247–57. http://dx.doi.org/10.3390/chemistry3040090.

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In this work, we describe a user-friendly procedure for the preparation of all the isomeric forms of the terpene linalool oxide. The presented method is based on the transformation of the linalool enantiomers into the corresponding diastereoisomeric mixtures of the two furanoid oxides and two pyranoid oxides. Taking advantage of the different steric hindrance of the hydroxyl functional groups, the pyranoid forms were separated as a diastereoisomeric mixtures of their benzoate esters. Conversely, the cis- and trans-furanoid isomers were transformed in the corresponding acetates, which were directly separated by chromatography. The hydrolysis of the latter esters afforded cis- and trans-furanoid linalool oxides whereas the same reaction performed on the benzoates mixture afforded a separable mixture of cis- and trans-pyranoid linalool oxide. Overall, the method features, as a unique mandatory requirement, the availability of both linalool enantiomers, and can be conveniently performed from a milligram to a multigram scale.

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37

Drmanic, Sasa, Bratislav Jovanovic, Aleksandar Marinkovic, and Milica Misic-Vukovic. "Investigations of the reactivity of pyridine carboxylic acids with diazodiphenylmethane in protic and aprotic solvents: Part II: Pyridine mono-carboxylic acid N-oxides." Journal of the Serbian Chemical Society 71, no. 2 (2006): 89–101. http://dx.doi.org/10.2298/jsc0602089d.

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The rate constants for the reaction of three isomeric pyridine mono-carbocylic acid N-oxides with diazodiphenylmethane were determined at 30 ?C in thirty two protic and aprotic solvents by the well known UV spectrophotometric method. The rate constants are generally higher than for pyridine mono-carboxylic acids in a similar range of solvents, except for picolinic acid N-oxide, and also higher in protic than in aprotic solvents. The determined rate constants were correlated with solvent parameters using the Kamlet-Taft solvatochromic equation bymeans of multiple regression analysis. The sign of the equation coefficients were in agreement with the postulated reaction mechanism. The mode of the influences of the solvent is discussed on the basis of the correlation coefficients, taking into account the specific structures of the pyridine mono-carboxylic acid N-oxides.

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38

Egan, Carmel, Maurice Clery, Anthony F. Hegarty, and Alan J. Welch. "Mechanism of reaction of isomeric nitrolic acids to nitrile oxides in aqueous solution." Journal of the Chemical Society, Perkin Transactions 2, no. 2 (1991): 249. http://dx.doi.org/10.1039/p29910000249.

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39

BUNCE, N. J., H. S. MCKINNON, R. J. SCHNURR, S. R. KEUM, and E. BUNCEL. "ChemInform Abstract: Fragmentation Pathways in the Mass Spectra of Isomeric Phenylazoxypyridine N-Oxides." ChemInform 23, no. 49 (2010): no. http://dx.doi.org/10.1002/chin.199249045.

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Müller, Arndt, Martin Knaack та Alfred Olbrich. "NMR Spectroscopic Characterization of IsomericS-Oxides Derived from α-Lipoic Acid". Magnetic Resonance in Chemistry 35, № 2 (1997): 111–14. http://dx.doi.org/10.1002/(sici)1097-458x(199702)35:2<111::aid-omr29>3.0.co;2-s.

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Černý, Ivan, Tereza Slavíková та Vladimír Pouzar. "Synthesis of (15E)-17β-hydroxy-5α-androstane-3,15-dione 15-[O-(Carboxymethyl)]oxime, New Hapten for Dihydrotestosterone (17β-hydroxy-5α-androstan-3-one)". Collection of Czechoslovak Chemical Communications 62, № 10 (1997): 1642–49. http://dx.doi.org/10.1135/cccc19971642.

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Abstract:

Addition of 4-methoxybenzyl alcohol to 3β-hydroxy-5α-androst-15-en-17-one gave the mixture of isomeric 15-(4-methoxyphenyl)methoxy derivatives from which, after acetylation and chromatography, the major 15β isomer was separated. Borohydride reduction gave 17β-hydroxy derivative which was protected as methoxymethyl ether. Oxidative cleavage of protecting group at position 15 and the subsequent Jones oxidation afforded corresponding 15-ketone. Its oximation with O-(carboxymethyl)hydroxylamine, deacetylation and methylation with diazomethane gave protected O-(carboxymethyl)oxime derivative with free hydroxy group at position 3. Its oxidation afforded dihydrotestosterone derivative and successive deprotection of position 17 and of carboxy group led to final (15E)-17β-hydroxy-5α-androstane-3,15-dione 15-[O-(carboxymethyl)]oxime. The title compound was designed as dihydrotestosterone hapten for heterologous radioimmunoassays.

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Wolińska, Ewa, and Wiesław Pucko. "Diversity of Reactions of Isomeric AminopyridineN-Oxides with Chloronitropyridines: An Experimental and Theoretical Study." Journal of Heterocyclic Chemistry 50, no. 3 (2013): 590–98. http://dx.doi.org/10.1002/jhet.1536.

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Butler, Matias, Pau Arroyo Mañez, and Gabriela M. Cabrera. "Differentiation of Isomeric Hydroxypyridine N-Oxides Using Metal Complexation and Electrospray Ionization Mass Spectrometry." Journal of The American Society for Mass Spectrometry 22, no. 3 (2011): 545–56. http://dx.doi.org/10.1007/s13361-010-0059-7.

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Möhrle, H., and R. Nießen. "Reaktionen von Isochinolinium-Salzen mit Hydroxylamin-Derivaten, 1. Mitteilung. N-(Nitrophenyl)-substituierte Verbindungen/Reactions of Isoquinolinium Salts with Hydroxylamine Derivatives, 1st Communication. N-(Nitrophenyl) Substituted Compounds." Zeitschrift für Naturforschung B 54, no. 2 (1999): 225–33. http://dx.doi.org/10.1515/znb-1999-0211.

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Abstract:

N-(Nitrophenyl) substituted isoquinolinium salts reacted with nucleophiles of the hydroxylamine type to different products depending on the electron withdrawing strength of the substituent. Mononitro compound 8 produced only the cyclic hydroxylamine 9a, the trinitroderivative 5 solely the ring cleaved oximes. The dinitro substance 1 held an intermediate position and gave rise to a labile cyclic hydroxylamine and a more stable ring opened Z-enamine; hydroxylamine ethers generated cyclic products which showed in dimethylsulfoxide ring chain isomerism with the tautomers.

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Hungerford, Natasha L., Steve J. Carter, Shalona R. Anuj, et al. "Analysis of Pyrrolizidine Alkaloids in Queensland Honey: Using Low Temperature Chromatography to Resolve Stereoisomers and Identify Botanical Sources by UHPLC-MS/MS." Toxins 11, no. 12 (2019): 726. http://dx.doi.org/10.3390/toxins11120726.

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Pyrrolizidine alkaloids (PAs) are a diverse group of plant secondary metabolites with known varied toxicity. Consumption of 1,2-unsaturated PAs has been linked to acute and chronic liver damage, carcinogenicity and death, in livestock and humans, making their presence in food of concern to food regulators in Australia and internationally. In this survey, honey samples sourced from markets and shops in Queensland (Australia), were analysed by high-resolution Orbitrap UHPLC-MS/MS for 30 common PAs. Relationships between the occurrence of pyrrolizidine alkaloids and the botanical origin of the honey are essential as pyrrolizidine alkaloid contamination at up to 3300 ng/g were detected. In this study, the predominant alkaloids detected were isomeric PAs, lycopsamine, indicine and intermedine, exhibiting identical MS/MS spectra, along with lesser amounts of each of their N-oxides. Crucially, chromatographic UHPLC conditions were optimised by operation at low temperature (5 °C) to resolve these key isomeric PAs. Such separation of these isomers by UHPLC, enabled the relative proportions of these PAs present in honey to be compared to alkaloid levels in suspect source plants. Overall plant pyrrolizidine alkaloid profiles were compared to those found in honey samples to help identify the most important plants responsible for honey contamination. The native Australian vines of Parsonsia spp. are proposed as a likely contributor to high levels of lycopsamine in many of the honeys surveyed. Botanical origin information such as this, gained via low temperature chromatographic resolution of isomeric PAs, will be very valuable in identifying region of origin for honey samples.

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Safiullin, R. L., A. N. Teregulova, A. R. Yarullin, M. Yu Ovchinnikov, and S. L. Khursan. "para-Substituent Effect on the Decay Kinetics of the Isomeric Forms of Aromatic Nitroso Oxides." Kinetics and Catalysis 63, no. 2 (2022): 172–79. http://dx.doi.org/10.1134/s0023158422020082.

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Khursan, V. S., E. M. Chainikova, and R. L. Safiullin. "Flash photolysis study of the reactivity of isomeric forms of arylnitroso oxides toward triphenyl phosphite." High Energy Chemistry 43, no. 6 (2009): 467–70. http://dx.doi.org/10.1134/s0018143909060095.

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Murray, Michael, Rachel M. Sefton, Robert Martini, and Alison M. Butler. "Induction of cytochromes P450 2B and 2E1 in rat liver by isomeric picoline N-oxides." Toxicology Letters 93, no. 2-3 (1997): 195–203. http://dx.doi.org/10.1016/s0378-4274(97)00092-1.

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Voronkov, Michael V., Alexander V. Gontcharov, Ramanaiah C. Kanamarlapudi, Paul F. Richardson, and Zhi-Min Wang. "Scaleable Syntheses of Isomeric Limonene Aziridines from the Commercially Available Mixture ofcis- andtrans-Limonene Oxides." Organic Process Research & Development 9, no. 2 (2005): 221–24. http://dx.doi.org/10.1021/op0498464.

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EGAN, C., M. CLERY, A. F. HEGARTY, and A. J. WELCH. "ChemInform Abstract: Mechanism of Reaction of Isomeric Nitrolic Acids to Nitrile Oxides in Aqueous Solution." ChemInform 22, no. 18 (2010): no. http://dx.doi.org/10.1002/chin.199118093.

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