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Kristopher J Kolonko et al.
The Journal of organic chemistry, 75(18), 6163-6172 (2010-08-26)
A variety of multinuclear NMR techniques, in combination with X-ray diffraction methods, were used to probe the solution structure of α-aryl lithium enolates of bis(4-fluorobenzyl) ketone (1-H), phenyl 4-fluorobenzyl ketone (2-H), and N,N-dimethyl 4-fluorophenylacetamide (3-H) in ethereal solvents and in
Jens Blotevogel et al.
Journal of chromatography. A, 1218(37), 6426-6432 (2011-08-13)
The widely used solvent hexamethylphosphoramide (HMPA) and its biological (metabolic) and chemical (abiotic) phosphoramide-based oxidation products may cause adverse health effects through occupational exposure and intake of contaminated groundwater. However, no current methods exist for the separation and the detection
Sean E Doris et al.
Journal of the American Chemical Society, 136(44), 15702-15710 (2014-10-11)
Cationic naked nanocrystals (NCs) are useful building units for assembling hierarchical mesostructured materials. Until now, their preparation required strongly electrophilic reagents that irreversibly sever bonds between native organic ligands and the NC surface. Colloidal instabilities can occur during ligand stripping
Hexamethylphosphoramide.
IARC monographs on the evaluation of carcinogenic risks to humans, 71 Pt 3, 1465-1481 (1999-09-07)
Scott E Denmark et al.
Journal of the American Chemical Society, 131(33), 11770-11787 (2009-08-01)
The mechanistic foundations of the Lewis base catalyzed aldol addition reactions have been investigated. From a combination of low-temperature spectroscopic studies ((29)Si and (31)P NMR) and kinetic analyses using a rapid-injection NMR apparatus (RINMR), a correlation of the ground states
Ge Gao et al.
Proceedings of the National Academy of Sciences of the United States of America, 101(15), 5417-5420 (2004-03-18)
It is found that the addition of hexamethylphosphoramide to the solution of an alkyne, Et(2)Zn, and (S)-1,1'-bi-2-naphthol in methylene chloride allows the generation of an alkynylzinc at room temperature and shows highly enantioselective additions to aldehydes. The mild condition for
Edward Szłyk et al.
Talanta, 84(1), 199-203 (2011-02-15)
New (31)P NMR internal reference standard - hexamethylphosphoroamide (HMPA) was applied for determination of added polyphosphates and their ionic forms in raw pork meat and meat products. Phosphate species were determined after extraction with a boric acid buffer (pH=9) and
Dhandapani V Sadasivam et al.
Journal of visualized experiments : JoVE, (72)(72), e4323-e4323 (2013-02-15)
Although initially considered an esoteric reagent, SmI(2) has become a common tool for synthetic organic chemists. SmI(2) is generated through the addition of molecular iodine to samarium metal in THF.(1,2-3) It is a mild and selective single electron reductant and
Tong-kuan Xu et al.
Guang pu xue yu guang pu fen xi = Guang pu, 25(6), 857-860 (2005-10-06)
A substituted 3H-indole quaternary ammonium molecule was designed and synthesized using hexamethylphosphoramide (HMPA) as a solvent. The products were purified and characterized by IR, 1H-NMR, MS and elemental analysis. The binding reaction of this compound with bovine serum albumin (BSA)
Wojciech Bartkowiak et al.
Journal of molecular modeling, 11(4-5), 317-322 (2005-07-12)
In this work, for the first time, a theoretical approach to describing the influence of hydrogen-bond formation on the electronic absorption spectrum and nonlinear optical properties of an aminobenzodifuranone derivative (ABF) that exhibits the largest positive solvatochromic shift compared to
Hexamethylphosphoramide.
Report on carcinogens : carcinogen profiles, 10, 137-138 (2004-08-26)
Samarium diiodide-induced reductive cross-coupling of nitrones with aldehydes and ketones.
Géraldine Masson et al.
Angewandte Chemie (International ed. in English), 41(10), 1772-1775 (2002-05-17)
Hexamethylphosphoramide.
Report on carcinogens : carcinogen profiles, 12, 229-231 (2011-08-20)
Masaharu Sugiura et al.
Chemical communications (Cambridge, England), (36)(36), 4309-4311 (2008-09-20)
Lewis bases such as Ph3P=O and HMPA catalyze the 1,4-reduction of alpha,beta-unsaturated ketones with trichlorosilane, and because the 1,2-reduction of aldehydes scarcely proceeded under the conditions, one-pot reductive aldol reactions with aldehydes were successfully achieved; preliminary studies using a chiral
Hexamethylphosphoramide.
Report on carcinogens : carcinogen profiles, 11, III141-III142 (2004-01-01)
Kamala Pant et al.
Environmental and molecular mutagenesis, 56(9), 777-787 (2015-04-29)
14-Hydroxycodeinone (14-HC) is an α,β-unsaturated ketone impurity found in oxycodone drug substance and has a structural alert for genotoxicity. 14-HC was tested in a combined Modified and Standard Comet Assay to determine if the slight decrease in % Tail DNA
Alain Deroussent et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 992, 30-35 (2015-05-06)
The antitumor drug, ifosfamide (IFO), requires activation by cytochrome P450 (CYP) to form the active metabolite, 4-hydroxyisfosfamide (4-OHIFO), leading to toxic by-products at high dose. In order to overcome these drawbacks, preactivated ifosfamide derivatives (RXIFO) were designed to release 4-OHIFO
Yun Ma et al.
Journal of the American Chemical Society, 128(48), 15399-15404 (2006-11-30)
Lithium diisopropylamide-mediated dehydrobrominations of exo-2-bromonorbornane, 1-bromocyclooctene, and cis-4-bromo-tert-butylcyclohexane were studied in THF solutions and THF solutions with added hexamethylphosphoramide (HMPA). Rate studies reveal a diverse array of mechanisms based on mono-, di-, and trisolvated monomers as well as triple ions.
Amanda C Jones et al.
Journal of the American Chemical Society, 130(19), 6060-6061 (2008-04-19)
Low-temperature rapid-injection NMR (RINMR) experiments were performed on tris(trimethylsilyl)methyllithium. In THF/Me2O solutions, the separated ion (1S) reacted faster than can be measured at -130 degrees C with MeI and substituted benzaldehydes (k >/= 2 s -1), whereas the contact ion
Jens Blotevogel et al.
Environmental science & technology, 44(15), 5868-5874 (2010-07-09)
Models used to predict the fate of aqueous phase contaminants are often limited by their inability to address the widely varying redox conditions in natural and engineered systems. Here, we present a novel approach based on quantum chemical calculations that
Clarisse Lejeune et al.
Journal of natural products, 76(5), 903-908 (2013-05-10)
The first biomimetic homodimerization of oroidin and clathrodin was effected in the presence HMPA and diphosphonate salts, strong guanidinium and amide chelating agents. The intermolecular associations probably interfere with the entropically and kinetically favored intramolecular cyclizations. Use of oroidin·(1)/2HCl salt
Bahar Zarabi et al.
Pharmaceutical research, 26(5), 1121-1129 (2009-01-23)
To evaluate the tumor targeting potential of N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-gadolinium(Gd)-RGDfK conjugates by magnetic resonance (MR) T1-mapping. HPMA copolymers with and without RGDfK were synthesized to incorporate side chains for Gd chelation. The conjugates were characterized by their side-chain contents and
Jens Blotevogel et al.
Environmental science & technology, 45(6), 2236-2242 (2011-02-22)
At contaminated field sites where active remediation measures are not feasible, monitored natural attenuation is sometimes the only alternative for surface water or groundwater decontamination. However, due to slow degradation rates of some contaminants under natural conditions, attenuation processes and
Robert B Grossman et al.
The Journal of organic chemistry, 68(3), 871-874 (2003-02-01)
Hexamethylphosphorous triamide (HMPT) and other phosphoramidites and phosphites have been found to be efficient catalysts for the Michael reaction of alkenones and alkynones with malonates, alpha-cyano esters, beta-keto esters, and nitro compounds. The relatively nontoxic, easily hydrolyzed HMPT catalyzes the
Chintada Nageswara Rao et al.
The Journal of organic chemistry, 77(20), 9199-9204 (2012-10-03)
The reaction of six substrates (diphenylacetylene, benzonitrile, methyl benzoate, phenylacetylene, naphthalene, and 1-chloro-4-ethylbenzene) with SmI(2) in the presence of MeOH or TFE was studied. The reactions were monitored under three different conditions: (a) irradiation, (b) irradiation in the presence of
Hexamethylphosphoramide as a highly reactive catalyst for the reversible-deactivation radical polymerization of MMA with an in situ formed alkyl iodide initiator
Wang Y, et al.
Polym. Chem., 8(39), 6073-6085 (2017)
Anthony J Pearson et al.
Organic letters, 6(13), 2121-2124 (2004-06-18)
[reaction: see text] Vicinal stereocontrol during nucleophilic addition of tert-butyl lithiopropionate to eta(6)-anisole chromium tricarbonyl complexes with differing para substituents has been studied. Excellent vicinal double stereoinduction (>99:1) was observed when the para substituent was Si(CH(3))(3), and this has been
Ann T Doherty et al.
Mutagenesis, 27(5), 533-539 (2012-04-12)
Although there are several in vivo tests for potential genotoxicity, with the possible exception of the transgenic rodent mutation models, none is specifically intended to assess increasing damage with chronic administration. In principle, peripheral blood lymphocytes would be expected to
Isidore E Decostaire et al.
Organic & biomolecular chemistry, 12(29), 5536-5543 (2014-06-24)
Peptide-based complex biomacromolecules are now optimally assembled by sequential ligation of unprotected peptide segments. However, this approach is still limited by the laborious chromatographic purification and handling steps needed for multiple successive chemoselective couplings, which leads to loss of material.
Drug-HPMA-HuIg conjugates effective against human solid cancer.
Blanka Ríhová et al.
Advances in experimental medicine and biology, 519, 125-143 (2003-04-05)
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