ChemInform Abstract: A Convenient Preparation of Acetone Solutions of Dimethyldioxirane.

Adam, Waldemar; Bialas, Joachim; Hadjiarapoglou, Lazaros P.

doi:10.1002/chin.199150130

Cited by 9 publications

(10 citation statements)

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“…AFB 1 was purchased from Aldrich Chemical Co. (Milwaukee, WI). AFB 1 - exo -8,9-epoxide was prepared by oxidizing AFB 1 in the presence of dimethyldioxirane, − as described …”

Section: Methodsmentioning

confidence: 99%

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B₁ Adduct

Liang

Brown

et al. 2015

Chem. Res. Toxicol.

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Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus, is oxidized by cytochrome P450 enzymes to aflatoxin B1-8,9-epoxide, which alkylates DNA at N7-dG. Under basic conditions, this N7-dG adduct rearranges to yield the trans-8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy aflatoxin B1 (AFB1–FAPY) adduct. The AFB1–FAPY adduct exhibits geometrical isomerism involving the formamide moiety. NMR analyses of duplex oligodeoxynucleotides containing the 5′-XA-3′, 5′-XC-3′, 5′-XT-3′, and 5′-XY-3′ sequences (X = AFB1–FAPY; Y = 7-deaza-dG) demonstrate that the equilibrium between E and Z isomers is controlled by major groove hydrogen bonding interactions. Structural analysis of the adduct in the 5′-XA-3′ sequence indicates the preference of the E isomer of the formamide group, attributed to formation of a hydrogen bond between the formyl oxygen and the N6 exocyclic amino group of the 3′-neighbor adenine. While the 5′-XA-3′ sequence exhibits the E isomer, the 5′-XC-3′ sequence exhibits a 7:3 E:Z ratio at equilibrium at 283 K. The E isomer is favored by a hydrogen bond between the formyl oxygen and the N4-dC exocyclic amino group of the 3′-neighbor cytosine. The 5′-XT-3′ and 5′-XY-3′ sequences cannot form such a hydrogen bond between the formyl oxygen and the 3′-neighbor T or Y, respectively, and in these sequence contexts the Z isomer is favored. Additional equilibria between α and β anomers and the potential to exhibit atropisomers about the C5–N5 bond do not depend upon sequence. In each of the four DNA sequences, the AFB1–FAPY adduct maintains the β deoxyribose configuration. Each of these four sequences feature the atropisomer of the AFB1 moiety that is intercalated above the 5′-face of the damaged guanine. This enforces the Ra axial conformation for the C5–N5 bond.

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“…AFB 1 was purchased from Aldrich Chemical Co. (Milwaukee, WI). AFB 1 - exo -8,9-epoxide was prepared by oxidizing AFB 1 in the presence of dimethyldioxirane, − as described …”

Section: Methodsmentioning

confidence: 99%

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B₁ Adduct

Liang

Brown

et al. 2015

Chem. Res. Toxicol.

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“…To a solution of 29-epi-GR24 (11 mg, 0.0369 mmol, 1 eq.) in CH 2 Cl 2 (1 mL) was added in a solution of freshly distilled dimethyldioxirane (Adam et al, 1991) acetone (2.1 mL, approximately 0.1 M) and stirred at 5°C for 12 h. The solution was allowed to reach room temperature, and the volatiles were evaporated under reduced pressure to give 11.5 mg (quantitative) of the lactone 36 (two diastereoisomers 7:3) as a white solid. (3R*,3aS*,8bS*)-3-Hydroxy-3-(methoxy((S*)-4-methyl-5-oxo-2,5-dihydrofuran-2-yloxy)methyl)-3,3a,4,8b-tetrahydro-2H-indeno[1,2-b]furan-2-one 37…”

Section: -((4-chlorophenyl)thio)-34-dimethylfuran-2(5h)-one 31mentioning

confidence: 99%

Structure-Activity Relationship Studies of Strigolactone-Related Molecules for Branching Inhibition in Garden Pea: Molecule Design for Shoot Branching

et al. 2012

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Initially known for their role in the rhizosphere in stimulating the seed germination of parasitic weeds such as the Striga and Orobanche species, and later as host recognition signals for arbuscular mycorrhizal fungi, strigolactones (SLs) were recently rediscovered as a new class of plant hormones involved in the control of shoot branching in plants. Herein, we report the synthesis of new SL analogs and, to our knowledge, the first study of SL structure-activity relationships for their hormonal activity in garden pea (Pisum sativum). Comparisons with their action for the germination of broomrape (Phelipanche ramosa) are also presented. The pea rms1 SL-deficient mutant was used in a SL bioassay based on axillary bud length after direct SL application on the bud. This assay was compared with an assay where SLs were fed via the roots using hydroponics and with a molecular assay in which transcript levels of BRANCHED1, the pea homolog of the maize TEOSINTE BRANCHED1 gene were quantified in axillary buds only 6 h after application of SLs. We have demonstrated that the presence of a Michael acceptor and a methylbutenolide or dimethylbutenolide motif in the same molecule is essential. It was established that the more active analog 23 with a dimethylbutenolide as the D-ring could be used to control the plant architecture without strongly favoring the germination of P. ramosa seeds. Bold numerals refer to numbers of compounds.

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“…A 0.054 M acetone solution of DMD (2.6 mL corresponding to 0.142 mmol) was added to a solution of methyl ester of EPA (100 mg; 0.316 mmol) in acetone (2 mL) at 0 °C. The reaction was monitored by spectrophotometry (335 nm) for the consumption of the dioxirane reagent and TLC for the formation of products . Eluent: 1:2 diethyl ether/ n -hexane; starting material 1 R f = 0.74, mix ( 4 and 5 ) R f = 0.54, mix ( 3 and 6 ) R f = 0.48, pure ( 2 ) R f = 0.39, bis-epoxide R f ≤ 0.26.…”

Section: Methodsmentioning

confidence: 99%

Trans Fatty Acids: Chemical Synthesis of Eicosapentaenoic Acid Isomers and Detection in Rats Fed a Deodorized Fish Oil Diet

Ferreri

Grabovskii

Aoun

et al. 2012

Chem. Res. Toxicol.

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Eicosapentaenoic acid (EPA) is a polyunsaturated fatty acid present in fish oils used for omega-3 enriched diets. The natural cis double bond geometry can be transformed to the trans configuration during the deodorization process utilized in the food industry. The analytical discrimination of the possible five monotrans regioisomers represents a limiting step for the recognition and structure-activity relationship in connection with the harmful effects of trans fatty acids in health. We carried out a dual synthetic strategy, providing new access to monotrans EPA isomers and valuable information on GC and NMR characteristics for further applications in metabolomics and lipidomics. This small library was used as an analytical reference for isomer determination in deodorized fish oils and the follow-up of rats fed fish oil diets, evidencing for the first time that monotrans EPA isomers are incorporated in liver mitochondrial membranes after dietary intake.

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ChemInform Abstract: A Convenient Preparation of Acetone Solutions of Dimethyldioxirane.

Cited by 9 publications

References 1 publication

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B₁ Adduct

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B₁ Adduct

Structure-Activity Relationship Studies of Strigolactone-Related Molecules for Branching Inhibition in Garden Pea: Molecule Design for Shoot Branching

Trans Fatty Acids: Chemical Synthesis of Eicosapentaenoic Acid Isomers and Detection in Rats Fed a Deodorized Fish Oil Diet

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ChemInform Abstract: A Convenient Preparation of Acetone Solutions of Dimethyldioxirane.

Cited by 9 publications

References 1 publication

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B1 Adduct

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B1 Adduct

Structure-Activity Relationship Studies of Strigolactone-Related Molecules for Branching Inhibition in Garden Pea: Molecule Design for Shoot Branching

Trans Fatty Acids: Chemical Synthesis of Eicosapentaenoic Acid Isomers and Detection in Rats Fed a Deodorized Fish Oil Diet

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Product

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About

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B₁ Adduct

DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B₁ Adduct