ChemInform Abstract: Synthesis and Application of Benzyl-TMS Derivatives as Bench Stable Benzyl Anion Equivalents.

ChemInform ◽  
2013 ◽  
Vol 44 (49) ◽  
pp. no-no
Author(s):  
Manas Das ◽  
Donal F. O'Shea
Keyword(s):  
Tms Derivatives

Increased urinary excretion of analogs of Krebs cycle metabolites and arabinose in two brothers with autistic features

1995 ◽  
Vol 41 (8) ◽  
pp. 1094-1104 ◽  
Author(s):  
W Shaw ◽  
E Kassen ◽  
E Chaves
Keyword(s):  
Mass Spectrum ◽  
Citric Acid ◽  
Krebs Cycle ◽  
Response Factor ◽  
Fragmentation Pattern ◽  
Acid Analog ◽  
High Concentrations ◽  
Mass Shifts ◽  
Derivatives Of ◽  
Tms Derivatives

Abstract A marked increase in analogs of Krebs cycle metabolites was found in the urine of two brothers with autistic features. These metabolites included citramalic, tartaric (3-OH-malic), and 3-oxoglutaric acids and compounds tentatively identified as a citric acid analog and partially identified as a phenylcarboxylic acid by the fragmentation pattern of the trimethylsilyl (TMS) derivatives of the compounds and mass shifts of the same compounds derivatized with perdeuterated N,O-bis(trimethylsilyl)trifluoroacetamide. The molecular mass of the TMS derivative of the tentatively identified citric acid analog was 596 Da, based on a finding of a significant M - 15 ion at m/z 581. The citric acid analog was excreted in quantities as high as 137 mmol/mol creatinine, based on the response factor of citric acid as a surrogate calibrator. A carbohydrate with a retention time and mass spectrum identical to arabinose was also found in high concentrations in the urine of these brothers.

scholarly journals GC-MS Metabolite Profile and Identification of Unusual Homologous Cannabinoids in High Potency Cannabis sativa

Planta Medica ◽  
2020 ◽  
Vol 86 (05) ◽  
pp. 338-347 ◽  
Author(s):  
Josep Basas-Jaumandreu ◽  
F. Xavier C. de las Heras
Keyword(s):  
Cannabis Sativa ◽  
Metabolite Profile ◽  
Side Chain ◽  
High Potency ◽  
Double Bond Migration ◽  
Phytochemical Investigation ◽  
Branched Chain ◽  
Fragmentation Patterns ◽  
Cis And Trans ◽  
Tms Derivatives

AbstractPhytochemical investigation of the lipids extracted from seeds of Cannabis sativa by GC-MS showed 43 cannabinoids, 16 of which are new. The extract is dominated by Δ9-tetrahydrocannabinolic acid (A) and its neutral derivative trans-Δ9-tetrahydrocannabinol-C5 (THC) Cis and trans-Δ9-tetrahydrocannabinol-C7 isomers with an ethyl-pentyl branched chain together with minor amounts of trans-Δ9-tetrahydrocannabinol with a methyl-pentyl C6 branched side chain were identified as new natural compounds. Four cannabichromene isomers with a C5 side chain are postulated to be derived from the double bond migration at the terminal isoprenyl unit. C7 cannabichromene together with the neutral and acidic forms of cannabinol-C7 were also detected. The mass spectrum of these homologues as trimethylsilyl (TMS) derivatives are presented, and the fragmentation patterns are discussed.

Improved GC/MS Analysis of Opiates with Use of Oxime-TMS Derivatives

1998 ◽  
Vol 43 (6) ◽  
pp. 14389J ◽  
Author(s):  
Michael Cremese ◽  
Alan H. B. Wu ◽  
Gina Cassella ◽  
Edward O'Connor ◽  
Kathy Rymut ◽  
...  
Keyword(s):  
Ms Analysis ◽  
Tms Derivatives

Synthesis and application of benzyl-TMS derivatives as bench stable benzyl anion equivalents

Tetrahedron ◽  
2013 ◽  
Vol 69 (31) ◽  
pp. 6448-6460 ◽  
Author(s):  
Manas Das ◽  
Donal F. O'Shea
Keyword(s):  
Tms Derivatives

Gas Chromatographic Determination of N-Nitrosodialkanolamines in Herbicide Di- or Trialkanolamine Formulations

1988 ◽  
Vol 71 (2) ◽  
pp. 328-333
Author(s):  
Yuk Y Wigfield ◽  
Mario D Lacfloix ◽  
Monique Lanouette ◽  
Narine P Gurprasad
Keyword(s):  
Chromatographic Determination ◽  
Aqueous Sample ◽  
Anion Exchange Column ◽  
Exchange Column ◽  
Modified Method ◽  
Extraction Tube ◽  
Cation Exchange Column ◽  
Aqueous Layer ◽  
Tms Derivatives

Abstract A modified method is presented to determine trace quantities of N-nitrosodiethanolamine (NDE1A) and yV-nitrosodiisopropanolamine (NDiPlA) in the triisopropanolamine (TiPlA) formulation of a mixture of picloram and 2,4-D. Aqueous sample is extracted with dichloromethane to remove organic interferences, and then the aqueous layer is passed sequentially through chloride anion exchange column, hydrogen cation exchange column, and Clin-Elut extraction tube. The final eluate, 10% acetone in ethyl acetate, is concentrated. The isolated nitrosamines are converted to the corresponding trimethylsilyl (TMS) derivatives and determined by gas chromatography (GC) on a DB1 column coupled with a thermal energy analyzer (GC-TEA). Eight samples of commercial TiPlA formulations are analyzed. Maximum detected levels of NDE1A and NDiPlA were 0.6 and 0.9 ppm, respectively, expressed relative to total weight of active ingredients. Analysis of 13 samples of herbicide DEIA formulation using a previously established method and a DB225 column gave NDE1A results of 0.7-6.0 ppm. NDiPlA was not detected in those samples. Results are confirmed by GC-mass spectrometry (GC/MS) with oxygen negative chemical ionization (ONCI) detection. Dectection limits for both nitrosamines are 0.05 or 0.07 ng (0.1 or 0.17 ppm) for GC-TEA detection, depending on the analytical columns used, and 20 pg (0.04 ppm) for GC/MS detection. Recoveries of NDE1A are 87-109% for DEIA formulation spiked at 2.6 and 3.9 ppm and 90-115% for TiPlA formulation spiked at 0.2-0.3 ppm. Similarly, recoveries of NDiPlA are 95.7-100% for the DEIA formulation spiked at 0.24 and 0.48 ppm, and 82-118% for the TiPlA formulation spiked at 0.2-0.3 ppm.

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