Epimer of 7-deoxyaklavinone

1981 ◽  
Vol 46 (9) ◽  
pp. 2129-2135 ◽  
Author(s):  
Josef V. Jizba ◽  
Petr Sedmera ◽  
Jindřich Vokoun ◽  
Margita Blumauerová ◽  
Zdenko Vaněk
Keyword(s):  
Natural Compounds ◽  
Cd Spectra ◽  
Minor Metabolite ◽  
A Minor ◽  
C Nmr

The structure (9R,10S)-7-deoxyaklavinone (VII) was assigned to a minor metabolite isolated from Streptomyces coeruleorubidus on the basis of 1H, 13C NMR and CD spectra. Evidence that compounds II and VII, isomeric with 7-deoxyaklavinone, are natural compounds is presented.

scholarly journals Competitive Diels–Alder and ene addition of N-arylmaleimides to 7-dehydrocholesteryl acetate

1992 ◽  
Vol 70 (11) ◽  
pp. 2730-2744 ◽  
Author(s):  
William J. Leigh ◽  
Donald W. Hughes ◽  
D. Scott Mitchell
Keyword(s):  
Molecular Mechanics ◽  
Nmr Spectra ◽  
Benzene Solution ◽  
Diels Alder ◽  
Spectroscopic Techniques ◽  
Two Dimensional ◽  
A Minor ◽  
C Nmr ◽  
Alder Adduct ◽  
Ene Addition

Thermolysis of N-phenyl, N-para-biphenyl, and N-para, para′-terphenylmaleimide with 7-dehydrocholesteryl acetate in benzene solution at 200 °C yields mixtures of four cycloadducts in relative yields that are essentially independent of the maleimide substituent. The three major products are those of ene addition to C7 of the steroid with abstraction of the proton at C9 or C14. The α-endo-Diels-Alder adduct is formed as a minor product. The structures of the adducts have been elucidated on the basis of one- and two-dimensional 1H and 13C NMR spectroscopic techniques, including homonuclear 1H decoupling, NOE, 1H–1H COSY, heteronuclear 1H–13C shift correlation, and TOCSY 2-D experiments, and the results of molecular mechanics (MMX) calculations. The combination of these techniques has made it possible to almost completely assign the 1H and 13C NMR spectra for two of the ene adducts and the Diels–Alder adduct from reaction of 7-dehydrocholesteryl acetate with N-phenyl maleimide.

Dicamba Uptake, Translocation, Metabolism, and Selectivity

Weed Science ◽  
1971 ◽  
Vol 19 (1) ◽  
pp. 113-117 ◽  
Author(s):  
F. Y. Chang ◽  
W. H. Vanden Born
Keyword(s):  
Hordeum Vulgare ◽  
Root Uptake ◽  
Tartary Buckwheat ◽  
Fagopyrum Tataricum ◽  
Sinapis Arvensis ◽  
Triticum Vulgare ◽  
Wild Mustard ◽  
Minor Metabolite ◽  
Anisic Acid ◽  
A Minor

Greenhouse studies indicated that 3,6-dichloro-o-anisic acid (dicamba) or its metabolic derivative was strongly accumulated in meristematic tissues of Tartary buckwheat (Fagopyrum tataricum(L.) Gaertn.) and wild mustard (Sinapis arvensisL.) following both foliar and root uptake. In barley (Hordeum vulgareL.) and wheat (Triticum vulgareL.), it was distributed throughout the plants. Detoxification of dicamba occurred in all four species though not at equal rates, and a common major metabolite was identified chromatographically as 5-hydroxy-3,6-dichloro-o-anisic acid. A minor metabolite, 3,6-dichlorosalicylic acid, was found in barley and wheat but not in Tartary buckwheat or wild mustard. The four species tolerated dicamba treatment in the order of wheat, barley, wild mustard, and Tartary buckwheat. This ranking corresponds with the ability of the plants to detoxify dicamba and is inversely related to the extent of dicamba absorption and translocation in them.

scholarly journals New Kaempferol 3,7-Diglycosides from Asplenium ruta-muraria and Asplenium altajense

2015 ◽  
Vol 10 (3) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Tsukasa Iwashina ◽  
Junichi Kitajima ◽  
Takayuki Mizuno ◽  
Sergey V. Smirnov ◽  
Oyunchimeg Damdinsuren ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Adjacent Area ◽  
Altai Mountains ◽  
A Minor ◽  
First Time ◽  
Minor Compound ◽  
C Nmr

A flavonoid was isolated from the fronds of Asplenium ruta-muraria and A. altajense (Aspleniaceae) collected in the Altai Mountains and adjacent area. The compound was identified as kaempferol 3- O- β-[(6″′- E-caffeoylglucopyranosyl)-(1→3)-glucopyranoside]-7- O- β-glucopyranoside (1) by UV, 1H and 13C NMR spectroscopy, LC-MS, and acid and alkaline hydrolyses. Another flavonoid (2) was isolated from A. altajense, as a minor compound, together with 1 and identified as deacylated compound 1, i.e. kaempferol 3- O-laminaribioside-7- O-glucoside. They were found in nature for the first time.

Bullerone, a novel sesquiterpenoid from Cyathusbulleri Brodie

1987 ◽  
Vol 65 (1) ◽  
pp. 15-17 ◽  
Author(s):  
William A. Ayer ◽  
Robert H. McCaskill
Keyword(s):  
Spectroscopic Methods ◽  
Skeletal Class ◽  
Minor Metabolite ◽  
A Minor

The structure of bullerone (3), a minor metabolite of the bird's nest fungus Cyathusbulleri Brodie, has been determined by a combination of chemical and spectroscopic methods. The possible biogenesis of bullerone, a new skeletal class of sesquiterpenoid, is discussed.

Accumulation and Metabolism of Bromacil in Pineapple Sweet Orange (Citrus sinensis) and Cleopatra Mandarin (Citrus reticulata)

Weed Science ◽  
1981 ◽  
Vol 29 (1) ◽  
pp. 1-4 ◽  
Author(s):  
L. S. Jordan ◽  
W. A. Clerx
Keyword(s):  
Citrus Sinensis ◽  
Sweet Orange ◽  
Citrus Reticulata ◽  
Minor Metabolite ◽  
A Minor ◽  
Orange Trees ◽  
Conjugated Metabolites ◽  
Cleopatra Mandarin

Young orange [Citrus sinensis (L.) Osbeck ‘Pineapple sweet orange’] trees are more sensitive to bromacil (5-bromo-3-sec-butyl-6-methyluracil) than young mandarin (Citrus reticulata Blanco ‘Cleopatra mandarin’) trees. Pineapple sweet orange roots absorbed twice as much 14C from bromacil, and accumulated three times as much in the leaves, as did Cleopatra mandarin. The amount of conjugated metabolites formed was the same in the roots of the two cultivars, but twice as much formed in the leaves of Cleopatra mandarin as in the leaves of Pineapple sweet orange. The principle metabolite was 5-bromo-3-sec-butyl-6-hydroxymethyluracil; a minor metabolite was tentatively identified as 5-bromo-3-(3-hydroxyl-1-methylpropyl)-6-methyluracil. No 5-bromouracil was detected. Citrus cultivars differ in their ability to accumulate and metabolize bromacil into conjugated nonphytotoxic compounds.

Neue Untersuchung über Inhaltsstoffe aus Aloe-und Rhamnus-Arten, XV [1] Homonataloin A und B aus Aloe lateritia: Reindarstellung, Konstitutions-und Konfigurationsaufklärung der Diastereomeren / A New Investigation on Constituents of Aloe and Rhamnus Species, XV [1] Hom onataloins A and B from Aloe lateritia: Isolation, Structure and Configurational Determ ination of the Diastereomers

1991 ◽  
Vol 46 (3-4) ◽  
pp. 177-182 ◽  
Author(s):  
Hans-W. Rauwald ◽  
Deo-D. Niyonzima
Keyword(s):  
Chemical Shifts ◽  
Optical Rotation ◽  
Coupling Constants ◽  
Cd Spectra ◽  
Large Coupling ◽  
H Nmr ◽  
Leaf Exudate ◽  
Hydroxyl Protons ◽  
Nmr Signals ◽  
C Nmr

From the leaf exudate of Aloe lateritia ENGLER the C-glucosyl com pounds homonataloin, aloeresin A and aloesin (synon. aloeresin B) were isolated together with the anthraquinone nataloeem odin-8-methylether and spectroscopically identified. Hom onataloin, widely distributed in Aloe species, was separated into homonataloin A and B by combined TLC and DCCC. In their 1 D and 2D 1H NMR spectra only the shifts of the 2′-hydroxyl protons of both glucosyl residues differ significantly, indicative of 10 S (A) resp. 10 S (B) configurations. In both com pounds the anthrone is in β-position of the D-glucopyranosyl, as determined by the large coupling constants of the anomeric protons. The 13C NMR signals are unambiguously assigned by the use of DEPT, APT and gated-decoupling methods. Only the chemical shifts of C -11 and C -14 show significant differences between both diastereomers due to the adjacent 2′-sugar hydroxyls. The two homonataloins differ mostly in optical rotation and circulardichroism due to different configurations at C - 10 of the anthrone part. The absolute configurations of the diastereomers are determined by correlation of their CD spectra with the CD spectra of the structural analogues 7-hydroxyaloins A and B, which shows that hom onataloin A is the 10 S, 1′S-compound and that homonataloin B has 10 R, 1′S-configuration.

scholarly journals Noninvasive Measurement of Murine Hepatic Acetyl-CoA13C-Enrichment Following Overnight Feeding with13C-Enriched Fructose and Glucose

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Filipa Carvalho ◽  
Joao Duarte ◽  
Ana Rita Simoes ◽  
Pedro F. Cruz ◽  
John G. Jones
Keyword(s):  
Drinking Water ◽  
Benzoic Acid ◽  
Noninvasive Measurement ◽  
Nmr Analysis ◽  
Acetyl Coa ◽  
Normal Chow ◽  
A Minor ◽  
Pyruvate Recycling ◽  
Amino Benzoic Acid ◽  
C Nmr

The13C-isotopomer enrichment of hepatic cytosolic acetyl-CoA of overnight-fed mice whose drinking water was supplemented with [U-13C]fructose, and [1-13C]glucose andp-amino benzoic acid (PABA) was quantified by13C NMR analysis of urinaryN-acetyl-PABA. Four mice were given normal chow plus drinking water supplemented with 5% [1-13C]glucose, 2.5% [U-13C]fructose, and 2.5% fructose (Solution 1) overnight. Four were given chow and water containing 17.5% [1-13C]glucose, 8.75% [U-13C]fructose and 8.75% fructose (Solution 2). PABA (0.25%) was present in both studies. UrinaryN-acetyl-PABA was analyzed by13C NMR. In addition to [2-13C]- and [1,2-13C]acetyl isotopomers from catabolism of [U-13C]fructose and [1-13C]glucose to acetyl-CoA, [1-13C]acetyl was also found indicating pyruvate recycling activity. This precluded precise estimates of [1-13C]glucose contribution to acetyl-CoA while that of [U-13C]fructose was unaffected. The fructose contribution to acetyl-CoA from Solutions 1 and 2 was 4.0 ± 0.4% and 10.6 ± 0.6%, respectively, indicating that it contributed to a minor fraction of lipogenic acetyl-CoA under these conditions.

scholarly journals Cytochrome P450-mediated metabolism of N-(2-methoxyphenyl)-hydroxylamine, a human metabolite of the environmental pollutants and carcinogens o-anisidine and o-nitroanisole

2008 ◽  
Vol 1 (3-4) ◽  
pp. 218-224 ◽  
Author(s):  
Karel Naiman ◽  
Helena Dračínská ◽  
Martin Dračínský ◽  
Markéta Martínková ◽  
Václav Martínek ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Cytochromes P450 ◽  
Environmental Pollutants ◽  
Human Metabolite ◽  
Hepatic Microsomes ◽  
Minor Metabolite ◽  
Reactive Compound ◽  
A Minor

Cytochrome P450-mediated metabolism ofN-(2-methoxyphenyl)-hydroxylamine, a human metabolite of the environmental pollutants and carcinogenso-anisidine ando-nitroanisoleN-(2-methoxyphenyl)hydroxylamine is a human metabolite of the industrial and environmental pollutants and bladder carcinogens 2-methoxyaniline (o-anisidine) and 2-methoxynitrobenzene (o-nitroanisole). Here, we investigated the ability of hepatic microsomes from rat and rabbit to metabolize this reactive compound. We found thatN-(2-methoxyphenyl)hydroxylamine is metabolized by microsomes of both species mainly too-aminophenol and a parent carcinogen,o-anisidine, whereas 2-methoxynitrosobenzene (o-nitrosoanisole) is formed as a minor metabolite. AnotherN-(2-methoxyphenyl)hydroxylamine metabolite, the exact structure of which has not been identified as yet, was generated by hepatic microsomes of rabbits, but its formation by those of rats was negligible. To evaluate the role of rat hepatic microsomal cytochromes P450 (CYP) inN-(2-methoxyphenyl)hydroxylamine metabolism, we investigated the modulation of its metabolism by specific inducers of these enzymes. The results of this study show that rat hepatic CYPs of a 1A subfamily and, to a lesser extent those of a 2B subfamily, catalyzeN-(2-methoxyphenyl)hydroxylamine conversion to form both its reductive metabolite,o-anisidine, ando-aminophenol. CYP2E1 is the most efficient enzyme catalyzing conversion ofN-(2-methoxyphenyl)hydroxylamine too-aminophenol.

Metabolism of Δ24-sterols by yeast mutants blocked in removal of the C-14 methyl group

1978 ◽  
Vol 56 (8) ◽  
pp. 794-800 ◽  
Author(s):  
A. M. Pierce ◽  
R. B. Mueller ◽  
A. M. Unrau ◽  
A. C. Oehlschlager
Keyword(s):  
Normal Growth ◽  
Resistant Mutant ◽  
Growth Conditions ◽  
Methyl Group ◽  
Substrate Preferences ◽  
Minor Metabolite ◽  
Methyl Sterols ◽  
A Minor ◽  
Yeast Mutants ◽  
Sterol Methyltransferase

We have investigated the metabolism of exogenously provided Δ24-sterols by whole cell cultures of a polyene-resistant mutant (D10) of Candida albicans blocked at removal of the C-14 methyl group. Comparison of the relative efficiencies of transmethylation at C-24 of selected sterol substrates revealed the following substrate preferences of the Candida Δ24-sterol methyltransferase (EC 2.1.1.41): zymosterol > 4α-methylzymosterol > 14α-methylzymosterol. Exogenous 4,4-dimethylzymosterol was not transmethylated by mutant D10. Incorporation of the 14C-labelled methyl group of S-adenosyl-L-[methyl-14C]methionine into the sterols of a D10 culture preloaded with zymosterol indicated that zymosterol was a better (40 ×) substrate than endogenous lanosterol. Feeding zymosterol to D10 and a polyene-resistant strain of Saccharomyces cerevisiae (Nys-P100) that was also blocked at removal of the C-14 methyl group gave 24-methyl sterols possessing Δ22 and ring B unsaturation. Mutant D10 was able to produce ergosterol from zymosterol whereas Nys-P100 produced ergosta-7,22-dienol. When grown in the presence of 3 μM 25-aza-24,25-dihydrozymosterol, a known inhibitor of the Δ24-sterol methyltransferase, Nys-P100 accumulated 14α-methylzymosterol, a minor metabolite in this mutant under normal growth conditions and hitherto unidentified as a yeast sterol.

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