Novel Iodine Reagent System for Regioselective Cleavage of Epoxides to Alcohols

Epoxides are converted regioselectively to corresponding higher substituted alcohols with greater yields using diphosphorus tetraiodide (P₂I₄) as a reducing agent and a catalytic amount of tetraethylammonium bromide at room temperature.     

One-neutron stripping reactions of <Superscript>11</Superscript>Be and <Superscript>19</Superscript>C on light target

We have calculated the one-neutron absorption cross-section and the longitudinal momentum distribution of the core fragment coming out from the breakup of ¹¹Be and ¹⁹C on ⁹Be target at 63 MeV/A and 88 MeV/A beam energies respectively. The reaction mechanism is treated within the framework of the eikonal approximation. The effective range of the nuclear interaction between the core and the valence neutron within the projectile has been determined by comparing the predicted stripping cross-section with the recently measured one. The effective range for ¹⁹C has been found to be smaller than that for ¹¹Be. It qualitatively indicates that ¹⁹C is slightly more halo than ¹¹Be. The smaller width, predicted as well as measured, of the LMD of ¹⁸C than ¹⁰Be also strengthens this fact. The experimental data concerning the LMD of core fragments have been well represented.      

Magnetization transfer and T2 quantitation in normal appearing cortical gray matter and white matter adjacent to focal abnormality in patients with traumatic brain injury

Traumatic brain injury (TBI) is one of the commonest causes of morbidity and mortality in the developed countries with posttraumatic epilepsy and functional disability being its major sequelae. The purpose of this study was to test the hypothesis whether the normal appearing adjacent gray and white matter regions on T2 and T1 weighted magnetization transfer (MT) weighted images show any abnormality on quantitative imaging in patients with TBI. A total of 51 patients with TBI and 10 normal subjects were included in this study. There were significant differences in T2 and MT ratio values of T2 weighted and T1 weighted MT normal appearing gray matter regions adjacent to focal image abnormality compared to normal gray matter regions in the normal individuals as corresponding contralateral regions of the TBI patient's group (p < 0.05). However the adjoining normal appearing white matter quantitative values did not show any significant change compared to the corresponding contralateral normal white matter values. We conclude that quantitative T2 and MT ratio values provide additional abnormality in patients with TBI that is not discernable on conventional T2 weighted and T1 weighted MT imaging especially in gray matter. This additional information may be of value in overall management of these patients with TBI.     

Surface studies on bimetallic thiocyanate ligand based single crystals of MnHg(SCN)4, CdHg(SCN)4 and ZnCd(SCN)4

Bimetallic SCN ligand based single crystals of manganese mercury thiocyanate (MMTC), cadmium mercury thiocyanate (CMTC) and zinc cadmium thiocyanate (ZCTC) are grown by slow solvent evaporation technique. The growth mechanism and surface features are investigated by optical microscopic techniques such as scanning electron microscopy (SEM) and atomic force microscopy (AFM). The laser induced surface damage measurements were carried out using a Q-switched Nd:YAG laser at 1064 nm with laser beam of 1.0 Hz and pulse duration 25 ps. The laser damage threshold values of MMTC, CMTC and ZCTC are found to be 15.9, 22.9 and 19.7 GW/cm², respectively. The SEM analysis of MMTC reveals the formation of elongated dendrite growth pattern caused by the fluctuations of Mn and Hg metal ligands when thiocyanate (SCN) bridges them. The etching study indicates the occurrence of different types of etch pit patterns like terraced triangles, pillars, pyramids and rods. The AFM images confirm the formation of three major hillocks with cavities in MMTC. The measured roughness values for CMTC crystal are very much lower than that of MMTC.     

Thermal conductivity of deep eutectic solvents

Journal of Thermal Analysis and Calorimetry - We have reported the thermal conductivities of three deep eutectic solvents (DESs). We have used choline chloride, N,N-diethyl ethanol ammonium...     

Radioanalytical separation and size-dependent ion exchange property of micelle-directed titanium phosphate nanocomposites

Nanocomposite titanium-phosphate (TiP) of different sizes was synthesized using Triton X-100 (polyethylene glycol-p-isooctylphenyl ether) surfactant. The materials were characterized by FTIR and powdered X-ray diffraction (XRD). The structural and morphological details of the material were obtained by scanning electron microscopy (SEM) and transmission electron microscopy. The SEM study was followed by energy dispersive spectroscopic analysis for elemental analysis of the sample. The important peaks of the XRD spectra were analyzed to determine the probable composition of the material. The average size distribution of the particles was determined by dynamic light scattering method. Ion exchange capacity was measured for different metal ions with sizes of the TiP nanocomposite and size-dependent ion exchange property of the material was investigated thoroughly. The nanomaterial of the smallest size of around 43 nm was employed to separate carrier-free ^137mBa from ¹³⁷Cs in column chromatographic technique using 1.0 M HNO₃ as eluting agent at pH 5.     

Ligand free open air copper(II) mediated aryl formamidation and amination of aryl halides

A simple synthetic procedure for direct formamidation and amination of aryl halides mediated by copper(II) salts was developed in open air, without an external ligand in formamide with potassium carbonate as a base. This approach is particularly efficient when electron active aryl halides are used as substrates. In these cases almost quantitative formamidation was observed.     

Cytotoxic and anti-oxidant activities of lanostane-type triterpenes isolated from Poria cocos

A new lanostane-type triterpene, 29-hydroxypolyporenic acid C (8), was isolated from the dried sclerotia of Poria cocos together with eight other known compounds pachymic acid (1), dehydropachymic acid (2), 3-acetyloxy-16alpha-hydroxytrametenolic acid (3), polyporenic acid C (4), 3-epi-dehydropachymic acid (5), 3-epi-dehydrotumulosic acid (6), tumulosic acid (7), and dehydrotumulosic acid (9). The compounds were identified by spectral analysis and comparison with spectroscopic data reported in the literatures. Although none of the nine (1 to 9) compounds showed promising antioxidant activity, 1 through 6 and 8 showed good cytotoxicity against human lung cancer cell line A549 and human prostate cancer cell line DU145. Interestingly, all these compounds exhibited better cytotoxicity towards A549 than DU145 cells.