bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laser‐Assisted Chemical Vapor Deposition of Boron
Authors: Boman M. , Bäuerle D. 
Published: May 2015

AbstractAr+ laser‐induced chemical vapor deposition (LCVD) of B from gaseous mixtures of BCl3 and H2 has been investigated for temperatures between 1000 K and 2250 K and for partial pressure within the ranges 25 mbar ≤ p(BCI3) ≤ 800 mbar and 10 mbar ≤p(H2) ≤ 400 mbar. For the lowest temperatures, deposition is controlled by the chemical kinetics which, with p(BCI3) = p(H2) = 100 mbar, is characterized by an apparent chemical activation energy of about 26.5 kcal/mol. In this regime, the deposited boron is amorphous. At high temperatures, deposition becomes limited by gas‐phase transport and polycrystalline boron with βrhombohedral structure is obtained.
SO2 Surface Chemistry on Metal Substrates
Authors: Sun Y.‐M. , Sloan D. , White J. M. 
Published: May 2015

AbstractThe surface chemistry, induced by thermal and non‐thermal methods, of SO2 on metal substrates is reviewed. The substrate temperature during dosing is important; regardless of metal, adsorption is dissociative at 300 K and molecular at 100 K. On Ni, Pd, and Pt, molecular adsorption occurs through the S and one O atom, and the molecular plane is perpendicular to the surface. However, on Ag and Cu, adsorption occurs only through the S with the molecular plane perpendicular to the surface. The differences can be attributed to the structure of the metal's molecular orbitals and their interactions with the SO2 orbitals. Upon heating, SO2 dissociates on all transition metal surfaces with the exception of Ag, Au, and Cu, where only molecular desorption occurs. On Pt, Fe, and Pd, additional reactions are observed between SO2 and its dissociation products. The nonthermal reactions induced by photons and electrons for monolayer coverages of SO2 on Ag (111) are dominated by molecular desorption. Desorption cross sections for 313 nm photons and 50eV electrons were 2.8 × 10−20 cm2 and −1 × 10−16 cm2, respectively. Nonthermal excitation mechanisms and quenching processes as well as interesting characteristics of SO2 under irradiation are also reviewed.
Synthesis of Heterobimetallic Phosphido‐Bridged W‐Mo Complexes with Chelating dppe and dppm Ligands
Authors: Wu Wen‐Jin , Hsu Jiun‐Yi , Wen Yuh‐Shang , Shyu Shin‐Guang 
Published: May 2015

AbstractReactions between and bidentate phosphines (dppm and dppe) produced complexes and with chelating dppm and dppe ligands as only products. No bridging bidentate phosphine complex was observed. Both complexes were spectroscopically characterized.
Gel Chemistry in Synthesis of AIPO4 Molecular Sieves
Authors: Prasad S. , Chen Wen‐Hua , Liu Shang‐Bin 
Published: May 2015

AbstractThe chemistry of ternary systems, Al2O3‐P2O5‐H2O, particularly on addition of an acid or an amine as fourth component was investigated with 31P and 27Al NMR spectroscopy.
Synthesis and Characterization of (βDiketonate)(7‐norbornadienyl acetate)Copper(l) Complexes, Single‐Crystal Structure of (hfac)Cu(7‐AcO‐NBD)
Authors: Chi Kai‐Ming , Houa Hung‐Chang , Chen Kuo‐Hsien , Shyu Shin‐Guang , Wen Yuh‐Sheng 
Published: May 2015

AbstractCopper(I) complexes of general formula (β‐diketonate)Cu(7‐AcO‐NBD), where 7‐AcO‐NBD = 7‐norbornadienyl acetate and β‐diketonate = 1,1,1,5,5,5‐hexafluoro‐2,4‐pentanedionate (1), 1,1,1‐trifluoro‐2,4‐pentanedionate (2), 2,4‐pentanedionate (3), 4,4,4‐trifluoro‐1‐(2‐thienyl)‐1,3‐butanedionate (4), 4,4,4‐trifluoro‐1‐phenyl‐1,3‐butanedionate (5), were prepared from reactions of CuCl with Na(β‐diketonate) in the presence of 7‐AcO‐NBD. AH compounds were characterized by elemental analyses, 1H, 13C, 19F NMR and IR spectra. Single‐crystal strucutre of compound 1 was determined by X‐ray diffraction analysis that showed a mononuclear copper species with coordination of a chelating β‐diketonate ligand through two oxygen atoms and the 7‐AcO‐NBD through its CC double bond and an oxygen atom in the solid state. For compound 1, the crystal data are: triclinic, space group \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm P}\bar 1 $\end{document}, a= 5.4519(14) Å, b= 11.852(3) Å, c= 13.304(3) Å, α = 74.721(20)° β = 80.220(20)°, γ= 76.848(19)°, Z = 2, RF = 0.060 and Rw = 0.064. Hot‐wall chemical vapor deposition experiments revealed that compound 1 is suitable as a precursor for deposition of copper films in the temperature range 170–260 °C.
A Convenient Synthesis of Antihyperlipoproteinemic Agent Gemfibrozil
Authors: Wang Hui‐Po , Lee On , Fan Chin‐Tsai , Lee Lain‐Tze 
Published: May 2015

AbstractA new synthesis of antihyperlipoproteinemic agent 2,2‐dimethyl‐5‐(2,5‐dimethylphenoxy)pentanoic acid (gemfibrozil, 1) is developed via hydrogenolysis of a novel β‐lactone 6, prepared from [2+2] cycloaddition of 3‐(2,5‐dimethylphenoxy)propanal with dimethylketene. The mild conditions applied in this process are especially convenient for the preparation of gemfibrozil on an industrial scale of production.
Regiospecific Displacement of the C‐B Bond of Tris[4‐(substituted)furan‐3‐yl]boroxines with C‐Sn Bond and C‐O Bond: Syntheses of 3,4‐Disubstituted Furans and 4‐Substituted‐3(2H)‐furanones,
Authors: Song Zhi Zhong , Wong Henry N. C. 
Published: May 2015

AbstractTris[4‐(substituted)furan‐3‐yl]boroxines2, prepared from the corresponding 4‐(substituted)‐3‐(trimethylsilyl) furan 1, were converted successfully to 4‐(substituted)‐3‐(tributylstannyl)furans3through palladium‐catalyzed cross‐coupling reactions with tributylstannyl chloride. Palladium‐catalyzed cross‐coupling reactions of3with organohalides afforded 3,4‐disubstituted furans4. Regiospecific iodination of 4‐(trimethylsilyl)‐3‐((tributylstannyl) furan (3a) gave 4‐iodo‐3‐(trimethylsilyl)furan (5), which reacted with excess ethyl acrylate under a common Heck‐condition to produce 2,3‐bis(trans‐ethoxycarbonylvinyl)‐4‐(trimethylsilyl)furan (6). A thermal 6‐electrocyclic reaction followed by dehydration converted6into benzo[2,3‐6]furan8. Oxidation of2generated the corresponding 4‐substituted‐3(2H)‐furanones9.
Trace Analysis of Heavy Metals with Two New Disodium Bisdithiocarbamates
Authors: Liu Lilian Kao , Cheng Tsai‐Heung , Young Dun‐Shyurng , Hsieh Tsing‐Pai 
Published: May 2015

AbstractTwo chelating reagents, disodium N,N′‐dibenzylethylenebisdithiocarbamate 1 and disodium piperazinebisdithiocarbamate 2, were synthesized and used to preconcentrate trace metals in aqueous samples. For analysis of Cu(II) using a UV‐vis spectrometer, Beer's law was obeyed from 5.0 μg L−1 to 6.0 mg L−1 for reagent 1, and from 0.2 mg L−1 to 6.0mg L−1 for reagent. 2. The chelation ratio for reagent 1 to Cu(II) was determined to be 1:1, with a formation constant 1.0 × 109 M−l. The dependence of extraction and extraction efficiency of reagent 1 on pH was also studied with an atomic absorption spectrometer for nine heavy‐metal ions‐Cu(II), Fe(III), Pb(II), Co(II), Cr(VI), Ni(II), Zn(II), Mn(II) and Cd(II). Except Cr(VI) and Mn(II), the recovery yields of the other seven metal ions were almost quantitative at pH = 4 − 6. The recovery was 82% for Cr(VI) at pH = 4 − 5, and 52% for Mn(II) at pH = 6 − 7.
Magnetic Properties of M3[Fe(Cn)6]2Xh2O (M = Co (II), Ni(II), Cu(II), Zn(II))
Authors: Shyu H. L. , Lin S. N. , Wei H. H. 
Published: May 2015

AbstractCompounds of the type M3[Fe(CN)6]2XH2O (M = Co(II), Ni(II), Cu(II), and Zn(II)) were prepared and magnetic properties of their powders were investigated by means of EPR spectra, Mössbauer effect and magnetic susceptibility measurements. The temperature dependence of the magnetization for the complexes Co3[Fe(CN)5]2‐ 10H2O, Ni3[Fe(CN)6]2‐10H2O and Cu3[Fe(CN)6]2‐4H2O revealed that below the critical temperatures 15, 22 and 20 K respectively, these complexes have zero‐field magnetization. The magnetic hysteresis at 10 K for Co(II), Ni(II) and Cu(II) complexes was observed. Mössbauer spectra at 4.2 K for the compounds are discussed.
Gelsemine Support Studies: Observation of an Unusual Free Radical Cyclization‐Fragmentation Sequence
Authors: Hart David J. , Kuzmich Daniel 
Published: May 2015

AbstractTreatment of vinylogous urethanes 9a and 9b with tri‐n‐butyl in hydride generated a tree radical that underwent cyclization‐fragmentation to afford oxindole‐ketones 10 and 11 in high yield. Vinylogous urethane 13, gave only cyclization‐reduction products 15 and 16 upon treatment with tri‐n‐butyltin hydride at 80 °C, but also afforded a low yield of cyclization‐fragmentation product 14 upon treatment with tris(trimethyl‐silyl)silane at 140 °C.
Constituents of Leaves of Tetradium Glabrifolium
Authors: Wu Tian‐Shung , Chang Feng‐Chu , Wu Pei‐Lin , Kuoh Chang‐Sheng , Chen Ih‐Sheng 
Published: May 2015

AbstractTwenty‐nine compounds including three alkaloids, live triterpenoids, five coumarins, seven benzenoids, two tannins, five flavonoids, one sugar and one nucleoside are isolated from leaves of Tetradium glabrifolium. Their structures are characterized on comparison of spectral data with literature values.
Synthesis of γ‐Butyrolactams by the Palladium‐Catalyzed Cyclization of N‐Allylbromoacetamides
Authors: Yang Shyh‐Chyun , Shea Fang‐Rong 
Published: May 2015

AbstractN‐Allylbromoacetamides undergo cyclization to give γ‐butyrolactams in the presence of palladium catalysts and a base.
A Novel Charge Distribution Method for the Numerical Solution of the Poisson‐Boltzmann Equation
Authors: Pan Jium‐Tyne , Peng Wen‐Jiun , Lin Thy‐Hou 
Published: May 2015

AbstractA charge distribution method to solve the linearized Poisson‐Boltzmann equation numerically through use of the finite difference method is proposed, The molecules are mapped by 1 and 0.25 Å grid systems. Each atom is modeled as a point charge and a weighted sum of point charge of every atom that is within its van der Waals radius with a grid point is assigned to the grid point. Depending on a charge distribution factor determined, the charge/grid (q/g) ratio calculated for every grid point inside a molecule can be fixed to a certain value. A grid size of the I Å grid is often fixed for mapping a small or large molecular system. Solvation energies for a group of small molecules calculated by the method arc comparable with those calculated by other methods and the grid energy calculated by the method is also reduced.
Syntheses and Characterization of Manganese‐Tellurolate Complexes by Using Chelating Metalloligand cis‐[Mn(Co)4(TePh)2]− and Potential Electrophilic TeMe+ Reagent
Authors: Liaw Wen‐Feng , Chiou Show‐Jen , Lee Way‐Zen , Lee Gene‐Hsiang , Peng Shie‐Ming 
Published: May 2015

AbstractThe cis‐[Mn(CO)4(TePh)2]−, similar to bidentate ligand PhTe(CH2)3TePh, acts as a “chelating metalloligand” for the synthesis of metallic tellurolate compounds. The reaction of cis[Mn(CO)4(TePh)2]− with BrMn(CO)5 in THF leads to a mixture of products[(CO)3,BrMn(μ‐TePh)2Mn(CO)4]− (1) and Mn2(μ‐TePh)2(CO)g (2). Complex 1 crystallizes in the triclinic space group Pl̄ with a = 11.309(3) Å, b = 14.780(5) Å, c = 19.212(6) Å, a = 76.05(3)° β = 72.31(3)°, γ = 70.41(3)° V = 2848(2) Å3, Z = 2. Final R = 0.034 and Rw = 0.035 resulting from refinement of 10021 total reflections with 677 parameters, Dropwise addition of (MeTe)2 to a solution of [Me3O][BF4] in CH3CN leads to formation of [Me2TeTeMe][BF4], a potential MeTe+ donor ligand. In contrast to oxidative addition of diphenyl ditelluride to [Mn(CO)s]− to give cis‐[Mn(CO)4(TePh)2]− which was thermally transformed into [(CO)3Mn(μ‐TePh)3Mn(CO)3]−, reaction of [Mn(CO)5]−with [Me2TeTeMe]+ proceeded to give the monomeric species MeTeMn(CO)5 as initial product which was then dimerized into Mn2(μ‐TeMe)2(CO)g (4).
Odorless Chemistry: A Gentle Reductionist Companion to Experiment
Authors: Schaefer Henry'F. 
Published: May 2015

AbstractComputational quantum chemistry has advanced over the past two decades to the point of recognition as a valuable co‐laborer with experiment. Several examples demonstrate this point. For each of the next 40 years, we predict that an additional 1% of chemical research will shift from experiment to computation. Thus by the year 2036 we foresee a picture of chemical research in which 50% of the effort is computational in nature.
Chemical Bonding State of Chlorine on Ag{100} as Determined by Angle‐Resolved Secondary Ion Mass Spectrometry
Authors: Chang Che‐Chen , Lung Chien‐Hua 
Published: May 2015

AbstractThe power of the angle‐resolved ion desorption technique for straightforward characterization of surfaces is demonstrated. The structural sensitivity of secondary ion desorption has led to a successful application of angle‐resolved ion sputtering yield measurements to the determination of the Cl chemical bonding structure on the Ag {100} surface. Angular distributions of the sputtered Cl− ions show that chlorine dissociates at the surface to yield a bonding state of atomic form at the room temperature. Both the polar and the azimuthal angle dependencies of the sputter intensity for Ag+ and Cl− ions reveal that the Cl adatom is chemi‐sorbed high above the topmost substrate layer of Ag atoms. At all Cl exposures, the Ag‐Cl bond is oriented along the <100> azimuth with the adsorbate occupying a C4 symmetry site, not an a‐top, a bridge, or a high symmetry site. Shadow‐cone enhanced ion desorption spectra show that die geometrical structure of the Cl chemisorbed surface changes slightly as the exposure is increased.
Determination of Ethion Residues in Soil by Extraction and by Mass Spectrometry Using Different Procedures
Authors: Lee Maw‐Rong , Tso Ju‐Chien , Yeh Yao‐Chia 
Published: May 2015

AbstractOptimized experimental procedures including time of extraction, extraction solvent in Soxhlet extraction technique were sought for detection of trace ethion residues in soil. The largest recoveries over 96% were achieved with a 1:1 mixture of methanol and acetone as extraction solvent for three hours. In comparing EI, CI, EI‐CAD, and PCI‐CAD modes of a four sector mass spectrometry for detection ethion, it was shown the best monitoring mode to be EI monitoring of the M+ of ethion, m/z 384, which fragments to give the m/z 231 product ion. The limit of detection obtained was 170 pg/g in soil.
Dispersed Fluorescence Spectroscopy and Transition Dipole Moment of HCO β 2A′‐X̄2A′
Authors: Chang Hui‐An , Fan Yang‐Hsiung , Chen I‐Chia 
Published: May 2015

AbstractDispersed fluorescence spectra of β 2A′ ‐ x̄ 2A′ transitions are measured on exciting HCO to the vibrational levels (0,0,0), (0,0,1), (0,1,0) and (1,0,0) of β 2A′ in a gas cell. Vibrational energies of bound and resonant states are determined for energy up to 17 500 cm−1 from the ground vibrational level of the x̄ 2A′ state. Rotationally resolved spectra of the bands β 2A′ ‐ x̄ 2A′ 203301, 214 and 202312 were recorded and analyzed. Abnormal intensities in the P, Q and R branches are due to the mechanism of “axis switching”. From the ratios of emission intensity of a‐ and b‐type transitions, without taking into account the varied lifetimes of rotational states of the upper electronic state, the directions of transition dipole moments of these bands are determined to be 39 − 43° to the inertial a axis.
Cooperative Study of Precision and Accuracy on the Determinations of Around‐Ppb Levels of Copper and Lead in Environmental Waters
Authors: Cheng Hwa‐Sheng , Pai Su‐Cheng , Yang Mo‐Hsiung , Chang Tsu‐Yen , Ho Wu‐Hsiung , Jen Jen‐Fon , Hsieh Chia‐Feng , Jian Shiuh‐Jen , Hsi Tai‐Sung , Cheng Kuang‐Lu , Lin Teh‐Hsien , Ho Siu‐Mei , Tsai Chung‐Ming 
Published: May 2015

AbstractThe results of a series of inter‐laboratory cross‐check on the determinations of ppb and sub‐ppb levels of copper and lead in environmental samples are described. Thirteen laboratories participated during a five‐stage comparison. Seven analytical methods and two pre‐concentration procedures were performed on certified and real samples. For controlled and blind standards at higher concentration levels (10 ppb or above) the data reported by different participants show good agreement for both elements regardless of the method chosen. However, for samples having lower concentrations (1‐10 ppb level), the relative standard deviation (R.S.D.) and bias increased. A high degree of scattering on data were demonstrated for a deep ocean water at less than 1 ppb level. The results of the present study give direct comparison between different analytical methods, and also reflect the average aptitude of analytical laboratories in Taiwan on the measurements of copper and lead in environmental samples.
Ferro‐and Antiferromagnetic Properties of Metal Complexes with Pyridine‐Substituted Nitronyl Nitroxide Radicals
Authors: Wei Ho‐Hsiang , Wong Hong‐Yue , Lee Gene‐Hsiang , Wang Yu 
Published: May 2015

AbstractThe synthesis, crystal structure and magnetic properties of the non‐transition metals; Cd(II), Zn(II), Hg(II), Mg(II) and the transition metals; Co(II), Ni(II), Cu(II) complexes with 2‐(4‐pyridyl)‐4,4,5,5‐tetra‐methylimidazolinyl‐l‐oxy‐3‐oxide (NITpPy) are presented. The compounds of free radical NITpPy, HgCl2(NITpPy), and Zn(acac)2(NITpPy) crystallize in the same monoclinic system of space group C2/c. The magnetic properties of the temperature‐dependent magnetic susceptibility of NITpPy and its metal complexes are discussed according to the Heisenberg model. A weak ferromagnetic coupling in NITpPy and a weak antiferromagnetic coupling in the metal complexes have been revealed.
Comparison of Electrospray Ionization and Fast Atom Bombardment Mass Spectrometry for the Analysis of Saponins from Alfalfa, Clover, and Mungbeans
Authors: Lee M. K. , Wang S. J. , Jurysta M. , Waller G. R. , Ling Y. C. 
Published: May 2015

AbstractThe determination of seven saponins in crude plant extracts by electrospray ionization mass spectrometry (ESI‐MS) and fast atom bombardment mass spectrometry (FAB‐MS) is described. Distinct protonated and natriated (Na‐adduct) molecular ions in ESI‐MS spectra readily provide molecular weight information, which can be further verified using clusters of molecular ions. Saponin mixtures can be analyzed by ESIMS on varying the potential difference between the capillary and skimmer in the ESI source to decompose impurities. ESI‐MS uses less amount of sample than that required by FAB‐MS. ESI‐MS does not produce structural information, however. The FAB‐MS spectra consist mainly of protonated and deprotonated molecular ions with limited structural information. (‐)‐FAB‐MS is more suitable for analyzing saponin samples than the (+)‐FAB‐MS.
Orbital Energy Order and the Through Bond Interaction in Homonuclear Diatomic Molecules
Authors: Chang Tse‐Chiang 
Published: May 2015

AbstractThe homonuclear diatomic molecules are the simplest systems having both the σ framework and the lone pair orbitals na and b for investigating their through space and through bond interaction. The striking orbital energy order ng∼ na+ nb > nn ∼ na ‐ nb has been accounted for by the through bond interaction. However, when the p‐content in the lone pair orbitals na and nb decreases, one may have the reverse orbital energy order: ng < ng. A reverse orbital energy order has been found in F2 and Cl2, whose na and nb are almost pure s‐type atomic orbitals. The reverse order also occurs in molecule N2 when the internuclear distance is larger man 1.5 Å. It is also found that the detail through space and through bond interaction and the eventual orbital energy order for ng and nu can be accounted for by the Fock operator within the localized molecular orbital space.
Butane Dehydrogenation Reaction on Sulfur Poisoned Group 10 Metal/SiO2 Catalysts
Authors: Chen Hsiu‐Wei , Chou Chi‐Hwei , Hong Cheng Tsung 
Published: May 2015

AbstractButane cracking and dehydrogenation reactions on silica supported Ni, Pt, Pd, and S, Pb modified Ni, Pt, Pd catalysts were studied via a fixed bed reaction system. Cracking reaction path prevailed when butane reaction was catalyzed by clean Ni, Pt, Pd and sulfur poisoned Ni catalysts. The addition of sulfur into Pt and Pd catalytic systems can shift the reaction path to dehydrogenation reaction. However, the deactivation problem due to carbonaceous deposit is not improved by the addition of sulfur into the catalytic system. The origin of the sulfur effect on the change of butane reaction pathway is discussed on the basis of the concentrations of Ph and S additives, oxygen perturbation effect, metal loading, carbonaceous deposit and reaction temperatures.
Electrochemical Oxidation of Glucose on Polycrystalline Gold Surface by Treating with Square Wave Potential Signal
Authors: Hsiao M. W. , Adzic R. R. 
Published: May 2015

AbstractThis study concerns with treatment of polycrystalline gold surface with square wave potential program to enhance the signal of electrochemical oxidation of glucose. After such perturbation the glucose oxidation wave is increased almost ten times. Consequently, gold is a useful electrode for sensor applications.
Preparation and Characterization of an Unusual Di‐Cobalt Complex; X‐Ray Crystal Structure of Co(CO)2(μ‐CO)(μ:η2,η4‐C4Ph4)Co(CO)2(PPh3)
Authors: Hong Fung‐E , Lue I‐Ren , Lin Chu‐Chieh 
Published: May 2015

AbstractReaction of [MoCo(CO)5(PPh3)2(η5‐C5H5)] (1) with diphenylacetylene in tetrahydrofuran at 50 °C yielded two heterobimetallic compounds, [MoCo(CO)4.(PPh3){μ‐PhC  CPh}(η5‐C5H5)] (4) and [MoCo(CO)5{μ‐PhC  CPh} (η5‐C5H5)] (5). However, an unexpected product, Co(CO)2(μ‐CO)(μ:η2,η4‐C4Ph4)Co(CO)2(PPh3) (6), was observed while attempting to grow the crystals for structural determination of 4. The X‐ray crystal structure of 6 was determined: triclinic, \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm P}\bar 1 $\end{document}, a = 11.654(2) Å, b = 12.864(2) Å, c = 13.854(2) Å, α = 89.67(2)°, β = 86.00(2)°, γ= 83.33(2)°, V = 2057.9(6) Å3 Z=2. In 6, two cobalt fragments are at apical and basal positions of the pseudo‐pentagonal pyramidal structure, respectively. The electron count for the apical cobalt fragments is 20, which is rather unusual. It is believed that 6 was formed after the fragmentation and recombination of the fragmented species of 4.
Antihypertensive Activity of dl‐Tetrahydropalmatine, an Active Alkaloid Isolated from the Tubers of Corydalis racemosa
Authors: Chu Lian‐Hwa , Hsu Feng‐Lin , Chueh Fu‐Yu , Niu Chiang‐Shan , Cheng Juei‐Tang 
Published: May 2015

AbstractThe antihypertensive activity of dl‐tetrahydropalmatine hydrochloride (THP), isolated from the tubers of Corydalis racemosa (Thunb.) Pers. (Papaveraceae), was investigated in spontaneously hypertensive rats (SHRs) using intravenous injection. A dose‐dependent lowering of blood pressure was observed in SHRs. Decrease of plasma noradrenaline was also obtained in SHRs that received injection of THP. Direct injection of THP into brain lowered the blood pressure and plasma noradrenaline. This antihypertensive action of THP appears to be produced mainly by an effect on central nervous system to lower sympathetic tone in SHRs.
The Enantioresolution of Methylthiohydantoin‐Amino Acids on R, S‐2‐hydroxypropyl Derivatized β‐Cyclodextrin Bonded Stationary Phase Using the Water‐Based Mobile Phase
Authors: Chen Shushi 
Published: May 2015

AbstractThe enantioresolution of thirteen methylthiohydantoin‐amino acids (MTH‐amino acids), which are substrates for producing D‐amino acids through enzyme‐catalyzed hydrolysis, is described on R, S‐2‐hydroxypropyl derivatized β‐cyclodextrin bonded stationary phase (RSP‐β‐CD CSP) with a water‐based mobile phase. The enantioresolution is relatively sensitive to the structural variation of group which is attached to the carbon at position five on methylthiohydantoin moiety and subsequently turns into side‐chain group of corresponding D‐amino acid produced after hydrolysis. The inclusion complexation is believed to be the mechanism responsible for the observed enantioresolution that cannot be reproduced either on native β‐cyclodextrin CSP under the same chromatographic conditions or on both CSPs using the acetonitrile‐based mobile phase. Approaches for enantioimprovement include varying the percentage of organic modifier in the mobile phase and using the buffer‐typed mobile phase such as triethylammonium acetate (pH 4.1).