Disease relevance of trimethylsilicon

• Urinary protein obtained from a patient with a highly malignant brain tumor (astrocytoma, grade IV) was adsorbed to trimethylsilyl controlled-pore glass beads and selectively eluted with acetonitrile to yield a high molecular weight (HMW) human transforming growth factor (hTGF) [1].
• Effect of cultural conditions on trimethylsilyl-sugar profiles of Streptococcus mutans [2].
• In this study, we investigated the effect of a novel retinobenzoic acid, 4-[3,5-bis (trimethylsilyl) benzamido] benzoic acid (TAC-101), on the growth of 4 human pancreatic-cancer cell lines; BxPC-3, MIAPaCa-2, CFPAC-1 and AsPC-1 [3].
• Submicrogram quantities of trimethylsilyl derivatives of cerebrosides obtained from the spleen of a patient with Gaucher's disease and from bovine brain were analyzed by direct probe inlet-chemical ionization mass spectrometry, using isobutane as the reagent gas [4].
• A novel retinoid, 4-[3,5-bis (trimethylsilyl) benzamido] benzoic acid (TAC-101), induces apoptosis of human ovarian carcinoma cells and shows potential as a new antitumor agent for clear cell adenocarcinoma [5].

High impact information on trimethylsilicon

• The structures of the products were confirmed by gas chromatography-mass spectrometry of the methyl ester trimethylsilyl ether derivatives as well as after characteristic epoxide ring opening catalytically with hydrogen leading to dihydroxy products [6].
• The four stereoisomers of 2-hydroxy-3-methylvaleric acid have been synthesized and the mass spectra of their trimethylsilyl derivatives recorded [7].
• Identification was by gas chromatography-mass spectrometry of the trimethylsilyl derivative and by analysis of the hydrolysis products [8].
• The IL 2 was obtained free of contaminating proteins by a simple process consisting of an initial batch purification on trimethylsilyl-controlled pore glass followed by reversed phase high pressure liquid chromatography [9].
• Following methylation of the carboxylic acid group and formation of trimethylsilyl ethers of the hydroxyl groups, the fragmentation pattern of the product was compatible with that of a monoglucuronide of 1,25-dihydroxyvitamin D3 [10].

Chemical compound and disease context of trimethylsilicon

• The cellular carbohydrates of Streptococcus mutans NCTC 10832 were converted to methyl glycoside trimethylsilyl ethers and analyzed by gas-liquid chromatography [2].
• Betaxolol, a beta selective adrenoceptor antagonist recently approved for the treatment of hypertension, was determined by monitoring in chemical ionization mode with ammonia the [MH]+ ions of the trimethylsilyl derivatives of the drug and of its internal standard [2H5)betaxolol) [11].

Biological context of trimethylsilicon

• Glycosylation of the trimethylsilyl derivative of 6-chloropyrazolo[3,4-d]pyrimidine-4-one unexpectedly gave the N2-glycosyl isomer 20 as the major product [12].
• On the basis of this structural information, new catalysts were prepared in which the "bay region" tert-butyl groups were replaced by trimethylsilyl groups [13].
• The target compounds 9-12 were obtained by an N1 regioselective intramolecular cyclization reaction of silylated 5-8 using trimethylsilyl trifluoromethanesulfonate (TMS triflate) as the catalyst [14].
• We used high-resolution glass capillary columns to study the trimethylsilyl derivatives of some acidic metabolites found in pooled urine specimens form control and postpartum subjects [15].
• Polyphosphoric acid trimethylsilyl ester promoted intramolecular acylation of an olefin by a carboxylic acid: convenient construction of C-18-functionalized delta14-hecogenin acetate [16].

Anatomical context of trimethylsilicon

• The major molecular species of amniotic fluid phosphatidylcholine were determined as diacylglycerol trimethylsilyl ether derivatives by gas-liquid chromatography with use of glass capillary columns [17].
• Benzo[r]pyrene (B[e]P) is metabolized by liver microsomes of untreated rats to trans-4,5-dihydroxy-4,5-dihydrobenzo(e)pyrene and 1- as well as 3-hydroxybenzo[e]pyrene as shown by g.l.c. and mass spectrometry of their trimethylsilyl ethers [18].
• Characterization of IV by NMR and of trimethylsilyl ethers of IV and V by gas chromatography-mass spectrometry was compatible with spectral data for samples of IV and V isolated previously after incubation of I with rat liver mitochondria in the presence of NADPH [19].
• The pure reticulocyte lipoxygenase converts 5,15-DiHETE via a lipoxygenase reaction to 5,14,15-trihydroxy-6,8,10,12-eicosatetraenoic acid (a lipoxin B isomer) as shown by GC/MS analysis of its trimethylsilyl ether [20].
• Two fractions containing different classes of oxysterols were then analyzed as trimethylsilyl derivatives by capillary gas liquid chromatography, using on-column injection and a temperature gradient from 70 to 200 degrees C. The detection limit was about 0.5 microgram/g dry weight for egg yolk powder [21].

Associations of trimethylsilicon with other chemical compounds

• Enzymatic hydrolysis of phosphoglycolate proceeds through O-P bond cleavage as determined by reaction in H218O and analysis of the trimethylsilyl derivatives of the reaction products by mass spectrometry [22].
• The products of the reaction of D-[2-13C]ribulose 1,5-bisphosphate with molecular oxygen in the presence of D-ribulose 1,5-bisphosphate carboxylase/oxygenase were analyzed, after dephosphorylation, as the trimethylsilyl derivatives of glycolate and glycerate by mass spectrometry [23].
• The mass spectrum of its trimethylsilyl ether derivative showed the very characteristic fragmentation pattern of catechol estrogens and was found to be practically identical with that of the corresponding derivative of the reference standard [24].
• Electron impact mass spectrometry of trimethylsilyl ether derivatives of the metabolite revealed a mass fragmentation pattern similar to that of the trimethylsilyl ether derivative of authentic 1,25-(OH)2D3 [25].
• Samples were analyzed for etorphine by thin-layer chromatography (TLC) with iodoplatinate preceded by XAD-2 resin extraction (sensitivity = 0.2 mug etorphine/ml of urine) and by gas-liquid chromatography (GLC) preceded by organic solvent extraction and trimethylsilyl derivatization (sensitivity = 0.1 mug etorphine/ml of urine) [26].

Gene context of trimethylsilicon

• CYP3A4 enzyme formats incubated with anabolic steroids, testosterone, 17alpha-methyltestosterone, metandienone, boldenone and 4-chloro-1,2-dehydro-17alpha-methyltestosterone, produced 6beta-hydroxyl metabolites identified as trimethylsilyl (TMS)-ethers by a gas chromatography-mass spectrometry (GC-MS) method [27].
• Preliminary results obtained from gas-liquid chromatography (GLC) analysis of the trimethylsilyl derivatives of aflatoxins RB1 and RB2 indicated that these compounds could furnish the basis for developing an analytical GLC method for aflatoxins B1 and B2 [28].
• Self-assembled monolayers (SAMs) of the acid-labile trimethylsilyl ether (TMS-OC(11)H(22)S)(2) (TMS adsorbate) was formed on gold [29].
• Gas-chromatographic retention indices are given, in terms of methylene units, for 155 metabolically important compounds (mostly organic acids) as trimethylsilyl derivatives on 10% OV-1 and 10% OV-17 columns [30].
• HDL lipids were submitted to preparative gas-liquid chromatography and diacylglycerols were then silylated using trimethylsilyl reagents [31].

Analytical, diagnostic and therapeutic context of trimethylsilicon

• The alpha anomeric configurations were inferred from the JC-1,H-1 heteronuclear coupling constants, and the L absolute configurations for all the monosaccharide residues were established by gas chromatography analysis of the trimethylsilyl (+/-)-2-butyl glycosides [32].
• The purification scheme consisted of sequential batch adsorption onto trimethylsilyl-controlled pore glass beads, high pressure ion exchange chromatography, and reverse phase high pressure liquid chromatography [33].
• The purification of PCT-GF was accomplished by a batch concentration on trimethylsilyl-controlled pore glass beads, followed by: gel filtration chromatography; hydrophobic interaction HPLC; and reverse-phase HPLC [34].
• Metabolites were characterized using fast atom bombardment-mass spectrometry, gas chromatography-mass spectrometry of the pentafluorobenzyl ester, trimethylsilyl ether derivatives and specific degradation reactions [35].
• Thus, it is unlikely that the abuse of etorphine could be diagnosed by urinalysis using the common screening methods of radioimmunoassay, EMIT, TLC preceded by XAD-2 resin extraction, or GLC preceded by organic solvent extraction and trimethylsilyl derivatization [26].

References