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1.
Cumulative evidence shows that eicosanoids such as prostaglandins, leukotrienes, thromboxanes and hydroxy eicosatetraenoic acids play an important role in associating inflammation with human colorectal cancer (CRC). In this study an ultra‐pressure liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method was developed and validated for the targeted profiling of eight relevant eicosanoids and the major metabolic precursor, arachidonic acid (AA), in human colon. Multiple reaction monitoring (MRM) experiments were performed in negative electrospray ionization mode. The metabolites were separated using a C18 column consisting of 1.7 µm ethylene‐bridged hybrid particles (100 × 2.1 mm i.d.) and gradient elution (50 to 95% of solvent B) with a mobile phase comprising water (0.1% formic acid) [solvent A] and acetonitrile (0.1% formic acid) [solvent B] at a flow rate of 0.4 mL/min. The analysis time for each sample was 5.5 min. Our UPLC/MS/MS method demonstrated satisfactory validation results in terms of selectivity, sensitivity, matrix effect, linearity, extraction efficiency, intra‐ and inter‐day precision, accuracy and autosampler stability. The method was applied for the clinical profiling of matched pairs of cancerous and normal colon mucosae obtained from eight colorectal cancer patients. Endogenous levels of AA and selected eicosanoids such as prostaglandin E2 (PGE2), prostacyclin (PGI2) [assayed as its stable hydrolytic product 6‐keto‐prostaglandin1α (6‐k PGF1α)] and 12‐hydroxy‐5Z,8Z,10E,14Z‐eicosatetraenoic acid (12‐HETE) were found to be significantly different (p <0.05; paired t‐test) between cancerous and normal mucosae. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
2.
Monir Amin 《Fresenius' Journal of Analytical Chemistry》1987,329(5):600-602
Summary A direct, quantitative, thin-layer chromatographic (TLC) method is described for the separation and determination of a PGE2-descendant (compound I = PGE2-desc.), a PGA2-descendant (compound II = PGA2-desc.) and a PGB2-descendant (compound III = PGB2-desc.) as pure substances and in pharmaceutical preparations. The extraction of the active ingredients is performed in a fully automated apparatus within 5 min. Using TLC compound I (UV-inactive substance) must be converted into compound III so that it can be measured at -max. 280 nm. Compound II can be measured both directly at -max. 224 nm and after conversion into compound III [1]. The conversion of PGE2-desc. and PGA2-desc. into PGB2-desc. was achieved after spraying the separated PG-spots on the TL-plates with KOH solution and heated. The TLC development was carried out on silica gel 60 F254 and measurement was direct on the plates by chromatogram spectrodensitometry using the reflection method. The method is also suitable for stability studies and has also proved useful in the analysis of the prostaglandin-derivatives in various pharmaceutical preparations.
Quantitative dünnschicht-chromatographische Bestimmung einiger Prostaglandinderivate der Untergruppen E2, A2 und B2相似文献
3.
《液相色谱法及相关技术杂志》2012,35(7):1265-1272
Abstract A continuous development technique using silica gel linear high performance TLC plates is described for the separation of prostaglandins 6-keto-F1α, F2α, E2, 13,14-dihydro-15-keto-F2α, 13–14-dihydro-15-keto-E2, and thromboxane B2. Complete separation of all six prostaglandins was achieved with a solvent system of ethyl acetate/acetone/acetic acid (90:5:1). The method is simple, rapid and provides excellent resolution of plasma prostaglandins prior to quantitation by gas chromatography-mass spectrometry. 相似文献
4.
Direct in situ determination of PGE1 in dioxane/water (1:1) at concentrations between 50 μg/ml and 1 mg/ml is described. HPTLC of PGE1 was carried out on HPTLC Kieselgel 60 o.F. plates; application (200 nl) was with a Nano-Appllcator and ethyl acetate/formic acid (400:5, v/v) served as mobile phase. The spots were located by dipping the plates into a 3% cupric acetate solution in 15% aqueous phosphoric acid, followed by heating at 120°C for 15 min. The plates were then evaluated directly at λ = 345 nm by chromatogram spectrometry. The coefficient of variation is 3.6%. 相似文献
5.
《合成通讯》2013,43(18):3233-3241
Abstract A concise synthesis of (2E,4Z)-2,4-heptadien-1-ol and (2E,4Z)-2,4-heptadienal is presented. Commercially available (Z)-2-penten-1-ol was converted to ethyl-(2E,4Z)-2,4-heptadienoate by reaction with activated MnO2 and (carboethoxymethylene)triphenylphosphorane in the presence of benzoic acid as a catalyst. Ethyl-(2E,4Z)-2,4-heptadienoate was converted to (2E,4Z)-2,4-heptadien-1-ol with LiAlH4. The alcohol was partially oxidized to (2E,4Z)-2,4-heptadienal with MnO2. The title compounds are male-specific, antennally active volatile compounds from the Saltcedar leaf beetle, Diorhabda elongata Brulle (Coleoptera: Chrysomelidae) and have potential use in the biological control of the invasive weed saltcedar (Tamarix spp). 相似文献
6.
Monir Amin 《Fresenius' Journal of Analytical Chemistry》1989,333(2):134-139
Summary Stability studies of a PGE2-descendant as pure substance, in solid, liquid and semisolid preparations is performed using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC).The extraction of the active ingredient from the pharmaceutical preparations is performed in a fully automated, electronically controlled extraction apparatus within 2–10 min.Using TLC the PGE2-descendant = UV-inactive substance must be converted (KOH solution, heat) into PGB2-descendant so that it can be measured at
max=280 nm. TLC was carried out on silica gel 60 F254 and the spot was directly measured on the plates by a chromatogram spectrophotometer using the reflection method. For HPLC a column of lichrosorb RP18 or Bondaback C18 was used. Mobile phases used were methanol-water-tetrabutylammonium-perchlorate for the first column and methanol-n-butanol-glacial acetic acid-water for the second column. The stability of PGE2-descendant was investigated in pure substance, vaginal tablets, powder mixtures, alcoholic aqueous solution, vaginal suppository and in freeze-dried ampoules. The examined preparations were stored at temperatures between 4°C and 60°C and were investigated within certain periods. It was found that the described analytical methods are suitable for the stability studies of this drug as they enable the separation of PGA2-descendant and PGB2-descendant, which occur as degradation products from PGE2-descendant.The prediction of the stability studies of PGE2-descendant indicated that this drug is unstable as well in pure substance as in pharmaceutical preparations. It was decomposed after short time even at room temperature to PGA2-descendant and PGB2-descendant.
Stabilitätsuntersuchungen eines Prostaglandin-Derivats der Untergruppe E2 in pharmazeutischen Zubereitungen相似文献
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8.
《Journal of Coordination Chemistry》2012,65(6):655-665
A novel vic-dioxime ligand with a thiourea moiety, (4E,5E)-1,3-bis{4-[(4-bromophenylamino)methylene]phenyl}-2-thiooxaimidazoline-4,5-dione dioxime (4) (bmdH2) has been synthesized from N,N′-bis{4-[(4-bromophenylamino)methylene]phenyl}thiourea and (E,E)-dichloroglyoxime. The bmdH2 ligand (4) forms transition metal complexes [M(bmdH)2] with a metal?:?ligand ratio of 1?:?2 with M?=?Ni(II), Co(II), and Cu(II). The mononuclear Ni(II), Co(II) and Cu(II) complexes, [Ni(bmdH)2] (5), [Co(bmdH)2] (6) and [Cu(bmdH)2] (7) have the metal ions coordinated through the two N,N atoms, as do most vic-dioximes. Elemental analyses, molar conductivity, magnetic susceptibility, IR, 1H NMR spectra, and UV-Visible spectroscopy were used to elucidate the structures of the ligand and its complexes. Conductivity measurements have shown that the mononuclear complexes are non-electrolytes. In addition, the ligands and metal complexes were screened for antibacterial and antifungal activities by agar well diffusion techniques using DMF as solvent. 相似文献
9.
《液相色谱法及相关技术杂志》2012,35(12):2507-2515
Abstract The partition coefficients of arachidonic acid (AA), prostaglandin (PG) H2 and PGE2 in the binary acetonitrile-hexane two-phase solvent system can be favorably modified by addition of diethyl ether. In the ternary two-phase solvent system acetonitrile-hexane-diethyl ether the partition coefficients of AA and the prostaglandins diverge as the ratio of ether to acetonitrile-hexane (1:1) is increased from 0.00 to 0.15 while the partition coefficients of PGH2 and PGE2 diverge as the ratio of ether to acetonitrile-hexane (1:1) is increased from 0.15 to 0.30. Isolation by CPC of PGH2 from the AA bioconversion reaction mixture is described. 相似文献
10.
Eleven TLC solvent systems were evaluated for the separation of prostaglandins F2α, E2 and D2, thromboxane B2, 12-OH-5,8,10-heptadecatrienoic acid (HHT), 12-OH-5,8,10,14-eicosatetraenoic acid (HETE), and arachidonic acid (AA) from each other. A three-solvent development TLC procedure, which can conveniently be used for routine resolution of mixtures of these metabolites on a single TLC plate, is reported. The method was used for quantification of the metabolites formed from 14C-labeled AA by washed human platelets. 相似文献
11.
(E)-1-Iodo-2-arylselenoethylenes 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 to afford (E)-1-arylseleno-substituted 1,3-enynes 3 in high yields. (E)-1-Arylseleno-substituted 1,3-enynes 3 were coupled with alkynylmagnesium bromides 4 in the presence of a catalytic amount of NiCl2(PPh3)2 to give stereoselectively (E)-enediynes 5 in good yields. 相似文献
12.
Lu S Nishimura K Hossain MA Jisaka M Nagaya T Yokota K 《Applied biochemistry and biotechnology》2004,118(1-3):133-153
Although some eicosanoids serve as potent natural ligands to activate peroxisome proliferator-activated receptor (PPARγ),
the ability of adipocytes to produce eicosanoids and regulate PPARγ remains unclear. Here, adipogenic 3T3-L1 cells were employed
to determine the gene expression of isoforms of biosynthetic enzymes in the arachidonate cyclooxygenase (COX) pathway and
the synthesis of prostaglandins (PGs). The expression of COX-2 was induced transiently in a biphasic manner upon the triggering
of the differentiation and maturation phases while COX-1 was constitutive. The exclusive expression of lipocalin-type PGD
synthase occurred and gradually increased during the maturation process along with the stable expression of PPARγ. Moreover,
we confirmed the formation of PGD2 from arachidonic acid by the mature adipocytes, suggesting conversion into PGJ2 derivatives. Even though cytosolic and membrane-associated subtypes of PGE synthase were expressed at relatively constant
levels, the ability of preadipocytes to produce PGE2 was greater than that of mature adipocytes in the cell response. The treatment of the mature adipocytes with exogenous PGD2, 15-deoxy-Δ12,14-PGJ2 and PGE2, in the presence of aspirin, enhanced the adipogenesis. These findings imply the specific roles of prostanoids produced by
the mature adipocytes in the maintenance of terminal differentiation through an autocrine control mechanism. 相似文献
13.
I. R. Gol'ding P. V. Petrovskii O. Ya. Borbulevych O. V. Shishkin W. Gruber Yu. G. Gololobov A. N. Shchegolikhin 《Russian Chemical Bulletin》1999,48(5):924-928
N-Substituted amides of 2-cyanopenta-2E,4-dienoic acid were synthesized by condensation ofN-substituted cyanoacetamides with acrolein in a dioxane-DMSO solution in the presence of Zn(OAc)2·2H2O as a condensing agent. X-ray diffraction study of 3-methylanilide of 2-cyanopenta-2E,4-dienoic acid (2d) demonstrated that the crystal structure of this compound is similar to that of 2-cyanopenta-2E,4-dienoic acid studied previously. However, the presence of themeta-tolyl substituent in molecule2d apparently results in the fact that the β-structure, which is typical of 2-cyanopenta-2E,4-dienoic acid, does not exist in the crystalline phase of2d.
Henkel Kommanditgesellschaft auf aktien, Deutschland, D-40191 Dusseldorf, Henkelstrasse, 67.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 933–937, May, 1999. 相似文献
14.
15.
M. Sc. Fabian Spitzer Prof. Dr. Marek Sierka Prof. Mario Latronico Prof. Dr. Piero Mastrorilli Dr. Alexander V. Virovets Prof. Dr. Manfred Scheer 《Angewandte Chemie (International ed. in English)》2015,54(14):4392-4396
By the reaction of [NacnacCuCH3CN] with white phosphorus (P4) and yellow arsenic (As4), the stabilization and enclosure of the intact E4 tetrahedra are realized and the disubstituted complexes [(NacnacCu)2(μ,η2:2‐E4)] ( 1 a : E=P, 1 b : E=As) are formed. The mono‐substituted complex [NacnacCu(η2‐P4)] ( 2 ), was detected by the exchange reaction of 1 a with P4 and was only isolated using low‐temperature work‐up. All products were comprehensively spectroscopically and crystallographically characterized. The bonding situation in the products as intact E4 units (E=P, As) was confirmed by theory and was experimentally proven by the pyridine promoted release of the bridging E4 tetrahedra in 1 . 相似文献
16.
《Analytical letters》2012,45(10):1909-1913
Abstract There are many different methods of quinolones determination. The most often used method of quinolones analysis is liquid chromatography. In this work some selected quinolones (cinoxacin, pipemidic acid) and fluoroquinolones (ofloxacin, pefloxacin) were separated with thin-layer chromatography (TLC). The two different mobile phases were used as follows: buffer solution (pH = 5.5)-methanol, 40:10 (v/v) and acetonitrile-water-acetic acid, 6:40:4 (v/v/v), respectively, for quinolones and fluoroquinolones. The following chromatographic parameters were calculated for these separations: RF, ?RF, RM, and RS. The possibility of qualitative determination of cinoxacin, pipemidic acid, ofloxacin, and pefloxacin using TLC was shown. 相似文献
17.
The best way to measure whole body production of the locally acting hormone prostaglandin E2 (PGE2) is to assess the accumulation of the major urinary metabolite, PGE2UM. A practical preparation of this delicate diacid is described. This synthetic PGE2UM will enable production of the antibodies that will be used to quantify this key metabolite. 相似文献
18.
Sirichan Tachai 《Natural product research》2016,30(19):2215-2219
From the rhizomes of Etlingera pavieana (Pierre ex Gagnep.) R.M. Sm., four phenylpropens, (E)-3-(4-methoxyphenyl)prop-2-en-1-amine (1), (E)-4-methoxycinamaldehyde (2), (E)-4-methoxycinamic acid (3) and (E)-1-methoxy-4-(3-methoxyprop-1-enyl)benzene (4), together with two other compounds, (E)-((E)-3-(4-methoxyphenyl)allyl)3-(4-hydroxyphenyl)acrylate (5) and 4-methoxybenzoic acid (6) were isolated. This is the first report on the presence of all compounds in Etlingera. Compounds 1 and 5 have been previously synthesised, but this is the first report of their isolation from a natural source. Compound 5 exhibited weak activity against Mycobacterium tuberculosis with MIC 50.00 μg/mL and cytotoxic activity against the KB, MCF7 and NCI-H187 cells with IC50 values of 25.11, 20.16 and 34.83 μg/mL, respectively. 相似文献
19.
Jan B. M. Wit Marcel Van der Sluis Fridrich Bickelhaupt 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Starting from dihalophosphaalkenes Mes?P=CHal2 (Hal = Cl, Br, I) we have been developing methodologies for the synthesis of (E)-Mes?P=CHHal, which can be converted to reactive phosphaalkenyl metal reagents. Dibromophosphaalkene 1 was reacted with n-butyllithium at -120 °C, furnishing 2 after chlorination of the intermediate carbenoid. Compound 2 was transformed to the (E)-chlorophosphaalkene 3 as shown (SCHEME 1). 相似文献