39 results on '"Sinhababu S"'
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2. Potentized Mercuric chloride and Nux vomica Facilitate Water Permeability in Erythrocytes of a Fresh-Water CatfishClarius batrachusUnder Acute Ethanol Intoxication
- Author
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Sukul, N. C., primary, De, A., additional, Sinhababu, S. P., additional, and Sukul, A., additional
- Published
- 2003
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3. Altered solution structure of alcoholic medium of potentized Nux vomica underlies its antialcoholic effect
- Author
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Sukul, A, primary, Sarkar, P, additional, Sinhababu, S P, additional, and Sukul, N C, additional
- Published
- 2000
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4. Effect of Nux vomica mother tincture, strychnine and Nux vomica 30c on the alcohol addiction of albino rats
- Author
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Sukul, N C, primary, Ghosh, S, additional, Sinhababu, S P, additional, and Sukul, A, additional
- Published
- 2000
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5. Antifilarial Effect of Solamargine Isolated from Solatium khasianum
- Author
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Ghosh, M., primary, Sinhababu, S. P., additional, Sukul, N. C., additional, Sahu, N. P., additional, and Mahato, S. B., additional
- Published
- 1994
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6. Variation in Fourier Transform Infrared Spectra of Some Homeopathic Potencies and Their Diluent Media.
- Author
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Sukul, N. C., Ghosh, Sudeshna, Sukul, A., and Sinhababu, S. P.
- Subjects
DRUGS spectra ,FOURIER transform infrared spectroscopy ,NUX vomica ,CLUB mosses ,SANTONIN ,INFRARED spectra ,HOMEOPATHIC research - Abstract
Objective: The aim of this study was to determine whether potentized homeopathic drugs and their diluent media differ from each other with respect to their Fourier transform infrared (FTIR) spectra. Design: FTIR spectra of Nux vomica 30C, Lycopodium 30C, Santonin 30C, Cina 30C, Cina 206C, Cina1006C, and their diluent media 90% ethanol and Ethanol 30C were obtained in the wave number range of 2000–1000 cm
−1 at 20°C. Potassium bromide powder soaked with the potencies, pressed into pellets, and air dried were used to measure the spectra. Because water structures in homeopathic potencies are thought to carry specific information on drug molecules and because O-H bending vibrational band (v2 ) exclusively belongs to water, the study was restricted to the bands in that wave number region. Alcohol has no absorption in the O-H bending region. Results: The potencies were found to differ from each other and their diluent media in the number of v2 bands, their wave number (cm−1 ), shape, and half-width (cm−1 ) of the bands. Conclusions: The number and other characteristics of the v2 band represent the number of hydrogen-bonded water species and their hydrogen-bonding strength, respectively. The potencies and their diluent media therefore differ from each other in the number of hydrogen-bonded water species and their hydrogen-bonding strength. The observation that KBr pellets soaked with a potentized drug retains its specific spectral absorption properties simply confirms that medicated sucrose globules, used in homeopathic dispensing, are capable of retaining the therapeutic properties of the drug. [ABSTRACT FROM AUTHOR]- Published
- 2005
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7. Antifilarial Effect of Solamargine Isolated from Solatium khasianum
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Ghosh, M., Sinhababu, S. P., Sukul, N. C., Sahu, N. P., and Mahato, S. B.
- Abstract
An active principle isolated from the ripe berries of Solarium khasianum is a steroidal alkaloid glycoside, solamargine, which killed in vitro 100% adults and microfilariae (mf) of Setaria cervi at a 4 mg/ml concentration in 60 and 88 min, respectively. The drug, when administered orally at 100 mg/ kg to rats, in which S. cervi adults were implanted intraperitoneally, reduced the blood mf count by more than 30% after the first phase of treatment for 10 days. The mf count showed an increase of 72% after the second phase of treatment. Following the third and the fourth phases of treatments, the mf density was reduced by more than 90%. One hundred percent reduction of mf count was obtained 15 days after the fourth and final phase of treatment which was of 5 days duration. At the evaluated dose (100 mg/kg × 4 phases), solamargine killed 100% of adult worms without incident toxicity.
- Published
- 1994
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8. Coordination-induced O-H/N-H bond weakening by a redox non-innocent, aluminum-containing radical.
- Author
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Sinhababu S, Singh RP, Radzhabov MR, Kumawat J, Ess DH, and Mankad NP
- Abstract
Several renewable energy schemes aim to use the chemical bonds in abundant molecules like water and ammonia as energy reservoirs. Because the O-H and N-H bonds are quite strong (>100 kcal/mol), it is necessary to identify substances that dramatically weaken these bonds to facilitate proton-coupled electron transfer processes required for energy conversion. Usually this is accomplished through coordination-induced bond weakening by redox-active metals. However, coordination-induced bond weakening is difficult with earth's most abundant metal, aluminum, because of its redox inertness under mild conditions. Here, we report a system that uses aluminum with a redox non-innocent ligand to achieve significant levels of coordination-induced bond weakening of O-H and N-H bonds. The multisite proton-coupled electron transfer manifold described here points to redox non-innocent ligands as a design element to open coordination-induced bond weakening chemistry to more elements in the periodic table., (© 2024. The Author(s).)
- Published
- 2024
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9. Recent advances in cooperative activation of CO 2 and N 2 O by bimetallic coordination complexes or binuclear reaction pathways.
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Sinhababu S, Lakliang Y, and Mankad NP
- Subjects
- Carbon Dioxide chemistry, Gases, Metals chemistry, Coordination Complexes chemistry, Metalloproteins
- Abstract
The gaseous small molecules, CO
2 and N2 O, play important roles in climate change and ozone layer depletion, and they hold promise as underutilized reagents and chemical feedstocks. However, productive transformations of these heteroallenes are difficult to achieve because of their inertness. In nature, these gases are cycled through ecological systems by metalloenzymes featuring multimetallic active sites that employ cooperative mechanisms. Thus, cooperative bimetallic chemistry is an important strategy for synthetic systems, as well. In this Perspective, recent advances (since 2010) in cooperative activation of CO2 and N2 O are reviewed, including examples involving s-block, p-block, d-block, and f-block metals and different combinations thereof.- Published
- 2022
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10. Cooperative Activation of CO 2 and Epoxide by a Heterobinuclear Al-Fe Complex via Radical Pair Mechanisms.
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Sinhababu S, Radzhabov MR, Telser J, and Mankad NP
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- Aluminum chemistry, Coordination Complexes chemical synthesis, Iron chemistry, Models, Chemical, Thermodynamics, Carbon Dioxide chemistry, Coordination Complexes chemistry, Cyclohexenes chemistry, Epoxy Compounds chemistry, Free Radicals chemistry
- Abstract
Activation of inert molecules like CO
2 is often mediated by cooperative chemistry between two reactive sites within a catalytic assembly, the most common form of which is Lewis acid/base bifunctionality observed in both natural metalloenzymes and synthetic systems. Here, we disclose a heterobinuclear complex with an Al-Fe bond that instead activates CO2 and other substrates through cooperative behavior of two radical intermediates. The complex Ldipp (Me)AlFp ( 2 , Ldipp = HC{(CMe)(2,6-i Pr2 C6 H3 N)}2 , Fp = FeCp(CO)2 , Cp = η5 -C5 H5 ) was found to insert CO2 and cyclohexene oxide, producing Ldipp Al(Me)(μ:κ2 -O2 C)Fp ( 3 ) and Ldipp Al(Me)(μ-OC6 H10 )Fp ( 4 ), respectively. Detailed mechanistic studies indicate unusual pathways in which (i) the Al-Fe bond dissociates homolytically to generate formally AlII and FeI metalloradicals, then (ii) the metalloradicals add to substrate in a pairwise fashion initiated by O-coordination to Al. The accessibility of this unusual mechanism is aided, in part, by the redox noninnocent nature of Ldipp that stabilizes the formally AlII intermediates, instead giving them predominantly AlIII -like physical character. The redox noninnocent nature of the radical intermediates was elucidated through direct observation of Ldipp Al(Me)(OCPh2 ) ( 22 ), a metalloradical species generated by addition of benzophenone to 2 . Complex 22 was characterized by X-band EPR, Q-band EPR, and ENDOR spectroscopies as well as computational modeling. The "radical pair" pathway represents an unprecedented mechanism for CO2 activation.- Published
- 2022
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11. Base-stabilized formally zero-valent mono and diatomic molecular main-group compounds.
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Yadav R, Sinhababu S, Yadav R, and Kundu S
- Abstract
Various compounds are known for transition metals in their formal zero-oxidation state, while similar compounds of main-group elements are recently realized and limited to only a few examples. Lewis-base-stabilized mono and diatomic molecular species (B
2 , C, C2 , Si, Si2 , Ge, Ge2 , Sn, P2 , As2 , Sb2 ) represent groundbreaking examples of main-group compounds with formally zero-oxidation state. In recent years, the isolation of low-valent main-group compounds has attracted increasing attention of both experimental and theoretical chemists. This is not only due to their fascinating electronic structures and exceptional reactivities, but also their use as valuable precursors for the synthesis of exotic yet important chemical species. This has led to a better understanding of the intricate balance of the donor-acceptor properties of the ligand(s) used to stabilize elements in a formally zero-oxidation state. Owing to the unusual oxidation state of the central element, many compounds containing formally zero-valent elements can efficiently activate otherwise inert small molecules. This review describes the synthesis, characterization, and reactivity of reported mono and diatomic formal zero-oxidation state main-group compounds. This review also emphasizes the comparative description of systems where different ligands are used to stabilize an element in its formal zero-oxidation state.- Published
- 2022
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12. A W/Cu Synthetic Model for the Mo/Cu Cofactor of Aerobic CODH Indicates That Biochemical CO Oxidation Requires a Frustrated Lewis Acid/Base Pair.
- Author
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Ghosh D, Sinhababu S, Santarsiero BD, and Mankad NP
- Subjects
- Aldehyde Oxidoreductases chemistry, Base Pairing, Carbon Monoxide chemistry, Copper chemistry, Density Functional Theory, Lewis Acids chemistry, Models, Molecular, Molecular Structure, Molybdenum chemistry, Multienzyme Complexes chemistry, Oxidation-Reduction, Tungsten chemistry, Aldehyde Oxidoreductases metabolism, Carbon Monoxide metabolism, Copper metabolism, Lewis Acids metabolism, Molybdenum metabolism, Multienzyme Complexes metabolism, Tungsten metabolism
- Abstract
Constructing synthetic models of the Mo/Cu active site of aerobic carbon monoxide dehydrogenase (CODH) has been a long-standing synthetic challenge thought to be crucial for understanding how atmospheric concentrations of CO and CO
2 are regulated in the global carbon cycle by chemolithoautotrophic bacteria and archaea. Here we report a W/Cu complex that is among the closest synthetic mimics constructed to date, enabled by a silyl protection/deprotection strategy that provided access to a kinetically stabilized complex with mixed O2- /S2- ligation between (bdt)(O)WVI and CuI (NHC) (bdt = benzene dithiolate, NHC = N-heterocyclic carbene) sites. Differences between the inorganic core's structural and electronic features outside the protein environment relative to the native CODH cofactor point to a biochemical CO oxidation mechanism that requires a strained active site geometry, with Lewis acid/base frustration enforced by the protein secondary structure. This new mechanistic insight has the potential to inform synthetic design strategies for multimetallic energy storage catalysts.- Published
- 2020
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13. The unique β-diketiminate ligand in aluminum(i) and gallium(i) chemistry.
- Author
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Zhong M, Sinhababu S, and Roesky HW
- Abstract
Over the past few decades, β-diketiminate ligands have been widely used in coordination chemistry and are capable of stabilizing various metal complexes in multiple oxidation states. Recently, the chemistry of aluminum and gallium in their +1 oxidation state has rapidly emerged. NacNacM(i) (M = Al, Ga; NacNac = β-diketiminate ligand) shows a two coordinate metal center comparable with singlet carbene-like species. The metal center also possesses a formally vacant p-orbital. In this article we present an overview of the last 10 years for aluminum(i) and gallium(i) stabilized by β-diketiminate ligands that have been widely explored in bond breaking and forming species.
- Published
- 2020
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14. Germylene stabilized group 12 metal complexes and their reactivity with chalcogens.
- Author
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Sinhababu S, Sharma MK, Mahawar P, Kaur S, Singh VK, Paliwal A, Yadav D, Kashyap HK, and Nagendran S
- Abstract
This manuscript reports the first examples of germylene stabilized cadmium complexes {[{(i-Bu)2ATIGe(i-Pr)}2(CdI2)] (3, monomeric), [{(i-Bu)2ATIGe(i-Pr)(CdCl2)}2] (6, dimeric), [{(i-Bu)2ATIGe(i-Pr)(CdI2)}2] (7, dimeric)} and novel germylene zinc complexes {[{(i-Bu)2ATIGe(i-Pr)}2(ZnCl2)] (2, monomeric), [{(i-Bu)2ATIGe(i-Pr)(ZnI2)}2] (5, dimeric)} (ATI = aminotroponiminate). The reactions of germylene zinc complex [{(i-Bu)2ATIGe(i-Pr)(ZnCl2)}2] (4) with elemental sulphur and selenium resulted in the first examples of germathione and germaselenone stabilized ZnCl2 complexes [{(i-Bu)2ATIGe(i-Pr)(S)(ZnCl2)}2] (8) and [{(i-Bu)2ATIGe(i-Pr)(Se)(ZnCl2)}2] (9), respectively. Compound 4 was obtained through the reaction of compound 2 with ZnCl2. Interconversions between the monomeric and dimeric zinc/cadmium complexes (2 ↔ 4/3 ↔ 7) are shown. Compounds 2-3 and 5-9 are characterized by multinuclear NMR spectroscopy and single crystal X-ray diffraction studies are performed on compounds 2-3, 5-7, and 9. To understand the nature of bonding in the first examples of germylene cadmium complexes, ab initio calculations are also carried out on compounds 3 and 7.
- Published
- 2019
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15. Treatment of Silylene-Phosphinidene with Chalcogens Resulted Exclusively in the Formation of Silicon-Bonded Chalcogens.
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Sinhababu S, Siddiqui MM, Sarkar SK, Münch A, Herbst-Irmer R, George A, Parameswaran P, Stalke D, and Roesky HW
- Abstract
Chalcogen-bonded silicon phosphinidenes LSi(E)-P-
Me cAAC (E=S (1); Se (2); Te (3); L=PhC(NtBu)2 ;Me cAAC=C(CH2 )(CMe2 )2 N-2,6-iPr2 C6 H3 )) were synthesized from the reactions of silylene-phosphinidene LSi-P-Me cAAC (A) with elemental chalcogens. All the compounds reported herein have been characterized by multinuclear NMR, elemental analyses, LIFDI-MS, and single-crystal X-ray diffraction techniques. Furthermore, the regeneration of silylene-phosphinidene (A) was achieved from the reactions of 2-3 with L'Al (L'=HC{(CMe)(2,6-iPr2 C6 H3 N)}2 ). Theoretical studies on chalcogen-bonded silicon phosphinidenes indicate that the Si-E (E=S, Se, Te) bond can be best represented as charge-separated electron-sharing σ-bonding interaction between [LSi-P-Me cAAC]+ and E- . The partial double-bond character of Si-E is attributed to significant hyperconjugative donation from the lone pair on E- to the Si-N and Si-P σ*-molecular orbitals., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)- Published
- 2019
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16. Synthesis of cAAC stabilized biradical of "Me 2 Si" and "Me 2 SiCl" monoradical from Me 2 SiCl 2 - an important feedstock material.
- Author
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Sinhababu S, Kundu S, Siddiqui MM, Paesch AN, Herbst-Irmer R, Schwederski B, Saha P, Zhao L, Frenking G, Kaim W, Stalke D, and Roesky HW
- Abstract
The cyclic alkyl(amino) carbene (cAAC) coordinated biradical of dimethylsilicon was isolated as (cAAC)2Me2Si (1), (cAAC = C(CH2)(CMe2)2N-2,6-i-Pr2C6H3), synthesized from the reduction of Me2SiCl2 using two equivalents of KC8 in the presence of two equivalents of cAAC. The reduction of Me2SiCl2 by one equivalent of KC8 in the presence of one equivalent of cAAC resulted in the stable dimethylsiliconchloride monoradical (cAAC)Me2SiCl (2).
- Published
- 2019
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17. Stable cyclic (alkyl)(amino)carbene (cAAC) radicals with main group substituents.
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Kundu S, Sinhababu S, Chandrasekhar V, and Roesky HW
- Abstract
Isolation and characterization of stable radicals has been a long-pursued quest. While there has been some progress in this field particularly with respect to carbon, radicals involving heavier p-block elements are still considerably sparse. In this review we describe our recent successful efforts on the isolation of stable p-block element radicals particularly those involving aluminum, silicon, and phosphorus.
- Published
- 2019
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18. Ge(ii) cation catalyzed hydroboration of aldehydes and ketones.
- Author
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Sinhababu S, Singh D, Sharma MK, Siwatch RK, Mahawar P, and Nagendran S
- Abstract
Well-defined germylene cations [(i-Bu)2ATI]GeOTf (4) and [(i-Bu)2ATIGe][GaCl4] (5) are isolated, and the catalytic utility of compound 4 for the hydroboration of a variety of aldehydes and ketones is reported (ATI = aminotroponiminate).
- Published
- 2019
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19. Donor-acceptor-stabilised germanium analogues of acid chloride, ester, and acyl pyrrole compounds: synthesis and reactivity.
- Author
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Sharma MK, Sinhababu S, Mahawar P, Mukherjee G, Pandey B, Rajaraman G, and Nagendran S
- Abstract
Germaacid chloride, germaester, and N -germaacyl pyrrole compounds were not known previously. Therefore, donor-acceptor-stabilised germaacid chloride (i-Bu)
2 ATIGe(O)(Cl) → B(C6 F5 )3 ( 1 ), germaester (i-Bu)2 ATIGe(O)(OSiPh3 ) → B(C6 F5 )3 ( 2 ), and N -germaacyl pyrrole (i-Bu)2 ATIGe(O)(NC4 H4 ) → B(C6 F5 )3 ( 3 ) compounds, with Cl-Ge[double bond, length as m-dash]O, Ph3 SiO-Ge[double bond, length as m-dash]O, and C4 H4 N-Ge[double bond, length as m-dash]O moieties, respectively, are reported here. Germaacid chloride 1 reacts with PhCCLi, KO t -Bu, and RLi (R = Ph, Me) to afford donor-acceptor-stabilised germaynone (i-Bu)2 ATIGe(O)(CCPh) → B(C6 F5 )3 ( 4 ), germaester (i-Bu)2 ATIGe(O)(O t -Bu) → B(C6 F5 )3 ( 5 ), and germanone (i-Bu)2 ATIGe(O)(R) → B(C6 F5 )3 (R = Ph 6 , Me 7 ) compounds, respectively. Interconversion between a germaester and a germaacid chloride is achieved; reaction of germaesters 2 and 5 with TMSCl gave germaacid chloride 1 , and 1 reacted with Ph3 SiOLi and KO t -Bu to produce germaesters 2 and 5 . Reaction of N -germaacyl pyrrole 3 with thiophenol produced a donor-acceptor-stabilised germaacyl thioester (i-Bu)2 ATIGe(O)(SPh) → B(C6 F5 )3 ( 10 ). Furthermore, the attempted syntheses of germaamides and germacarboxylic acids are also discussed., (This journal is © The Royal Society of Chemistry 2019.)- Published
- 2019
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20. Isolation of Transient Acyclic Germanium(I) Radicals Stabilized by Cyclic Alkyl(amino) Carbenes.
- Author
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Siddiqui MM, Sarkar SK, Sinhababu S, Ruth PN, Herbst-Irmer R, Stalke D, Ghosh M, Fu M, Zhao L, Casanova D, Frenking G, Schwederski B, Kaim W, and Roesky HW
- Abstract
Despite the notable progress in the stabilization of main group radicals by NHCs and cAACs, no germanium radicals have been isolated so far due to synthetic challenges. Stabilization of neutral [:E
I R]• (E = Si, Ge) radicals is an uphill task, as these reactive transient species are highly susceptible to dimerization. Herein, we report the synthesis of acyclic neutral germanium(I) radicals Cy-cAAC:GeN(SiMe3 )Dip (1) and Me-cAAC:GeN(SiPh3 )Mes (2) obtained by the reduction of [Ar(SiR3 )NGeCl3 ] with KC8 in the presence of cAAC. Compounds 1 and 2 are well characterized by single crystal X-ray structural analysis, cyclic voltammetry, and EPR spectroscopy. Furthermore, the structure and bonding of compounds 1 and 2 have been investigated by theoretical methods.- Published
- 2019
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21. Silanylidene and Germanylidene Anions: Valence-Isoelectronic Species to the Well-Studied Phosphinidene.
- Author
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Siddiqui MM, Sinhababu S, Dutta S, Kundu S, Ruth PN, Münch A, Herbst-Irmer R, Stalke D, Koley D, and Roesky HW
- Abstract
The reduction of TipMCl
3 (Tip=2,4,6-triisopropylphenyl) (M=Si, Ge) with KC8 in the presence of cyclic alkyl(amino) carbene (cAAC) afforded the acyclic silanylidene and germanylidene anions in the form of potassium salt [K(cAAC)MTip]2 (M=Si (1); Ge (2)). The silanylidene and germanylidene anions are valence-isoelectronic to the well-studied phosphinidene and are a new class of acyclic anions of Group 14. Compounds 1 and 2 were isolated and well characterized by NMR and single-crystal X-ray structure analysis. Furthermore, the structure and bonding of compounds 1 and 2 was investigated by computational methods., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2018
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22. Comparison of Two Phosphinidenes Binding to Silicon(IV)dichloride as well as to Silylene.
- Author
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Kundu S, Sinhababu S, Siddiqui MM, Luebben AV, Dittrich B, Yang T, Frenking G, and Roesky HW
- Abstract
The cyclic alkyl(amino) carbene (cAAC) anchored silylene with two phosphinidenes was isolated as (cAAC)Si{P(cAAC)}
2 (3) at room temperature, which was synthesized from the reduction of (Cl2 )Si{P(cAAC)}2 (2) using 2 equiv of KC8 . Compound 2 resulted from the reaction of 2 equiv of (cAAC)PK (1) with 1 equiv of SiCl4 . Compounds 2 and 3 are the first examples where two terminal phosphinidenes are binding each to a silicon center characterized by single crystal X-ray structural analysis. Furthermore, the structure and bonding of compounds 2 and 3 have been investigated by theoretical methods for comparison.- Published
- 2018
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23. Pseudohalogenogermylenes versus Halogenogermylenes: Difference in their Complexation Behavior towards Group 6 Metal Carbonyls.
- Author
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Sharma MK, Sinhababu S, Yadav D, Mukherjee G, Rajaraman G, and Nagendran S
- Abstract
Pseudohalogenogermylenes [(iBu)
2 ATI]GeY (Y=NCO 4, NCS 5) show different coordination behavior towards group 6 metal carbonyls in comparison to the corresponding halogenogermylenes [(iBu)2 ATI]GeX (X=F 1, Cl 2, Br 3) (ATI=aminotroponiminate). The reactions of compounds 4-5 and 1-3 with cis-[M(CO)4 (COD)] (M=Mo, W, COD=cyclooctadiene) gave trans-germylene metal complexes {[(iBu)2 ATI]GeY}2 M(CO)4 (Y=NCO, M=Mo 6, W 11; Y=NCS, M=Mo 7) and cis-germylene metal complexes {[(iBu)2 ATI]GeX}2 M(CO)4 (M=Mo, X=F 8, Cl 9, Br 10; M=W, X=Cl 12), respectively. Theoretical studies on compounds 7 and 9 reveal that donor-acceptor interactions from Mo to Ge atoms are better stabilized in the observed trans and cis geometries than in the hypothetical cis and trans structures, respectively., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2018
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24. A Route to Base Coordinate Silicon Difluoride and the Silicon Trifluoride Radical.
- Author
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Sinhababu S, Kundu S, Paesch AN, Herbst-Irmer R, Stalke D, Fernández I, Frenking G, Stückl AC, Schwederski B, Kaim W, and Roesky HW
- Abstract
Silicon difluoride (SiF
2 ) is highly unstable at room temperature and condenses at this temperature rapidly to a polymeric material of unknown structure. Therefore, the isolation of a stable monomeric silicon difluoride species is a challenging task. The cyclic alkyl(amino) carbene (cAAC) coordinated silicon difluoride was isolated as (cAAC)2 SiF2 (2), synthesized from the reduction of cAAC-SiF4 (1) by using two equivalents of KC8 in the presence of one equivalent of cAAC. In the solid state, compound 2 is stable at room temperature for a long time under inert conditions. The reduction of compound 1 in the presence of one equivalent KC8 resulted in the first stable silicon trifluoride monoradical (cAAC)SiF3 (3)., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2018
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25. Reagent for Introducing Base-Stabilized Phosphorus Atoms into Organic and Inorganic Compounds.
- Author
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Kundu S, Sinhababu S, Luebben AV, Mondal T, Koley D, Dittrich B, and Roesky HW
- Abstract
The cyclic alkyl(amino) carbene (cAAC) stabilized monoanionic phosphorus atom in the form of lithium phosphinidene [cAACPLi(THF)
2 ]2 (1) has been isolated as a molecular species and characterized by single crystal X-ray structure analysis. Furthermore, the structure and bonding of compound 1 has been investigated by theoretical methods. The utilization of the lithium phosphinidene as a phosphorus transfer reagent for a wide range of organic and inorganic substrates has been investigated. Herein, we report on the preparation of fascinating compounds containing P-C, P-Si, P-Ge, and P-P bonds using a single step with a base-stabilized phosphorus atom.- Published
- 2018
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26. Synthesis and characterization of Lewis base stabilized mono- and di-organo aluminum radicals.
- Author
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Kundu S, Sinhababu S, Dutta S, Mondal T, Koley D, Dittrich B, Schwederski B, Kaim W, Stückl AC, and Roesky HW
- Abstract
Two cyclic (alkyl)(amino)carbene (cAAC) stabilized mononuclear neutral radicals of aluminum have been synthesized. They contain an ethyl [(cAAC)
2 AlClEt (1)] and as well a diethyl group [(cAAC)2 AlEt2 (2)], and have been prepared from the reduction of EtAlCl2 and Et2 AlCl, respectively, with KC8 . Compounds 1 and 2 are monoradicals, which were confirmed by EPR measurements to have the spin located on the carbene carbon of one of the cAAC ligands.- Published
- 2017
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27. Organosilicon Radicals with Si-H and Si-Me Bonds from Commodity Precursors.
- Author
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Kundu S, Samuel PP, Sinhababu S, Luebben AV, Dittrich B, Andrada DM, Frenking G, Stückl AC, Schwederski B, Paretzki A, Kaim W, and Roesky HW
- Abstract
The cyclic alkyl(amino) carbene (cAAC) stabilized biradicals of composition (cAAC)
2 SiH2 (1), (cAAC)SiMe2 -SiMe2 (cAAC) (2), and (cAAC)SiMeCl-SiMeCl(cAAC) (3) have been isolated as molecular species. All the compounds are stable at room temperature for more than 6 months under inert conditions in the solid state. All radical species were fully characterized by single-crystal X-ray structure analysis and EPR spectroscopy. Furthermore, the structure and bonding of compounds 1-3 have been investigated by theoretical methods. Compound 1 contains the SiH2 moiety and this is the first instance, where we have isolated 1 without an acceptor molecule.- Published
- 2017
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28. A cationic aluminium complex: an efficient mononuclear main-group catalyst for the cyanosilylation of carbonyl compounds.
- Author
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Sharma MK, Sinhababu S, Mukherjee G, Rajaraman G, and Nagendran S
- Abstract
A structurally characterized cationic aluminium complex [(AT)Al(DMAP)]
+ [OTf]- (3) stabilized through a relatively nonbulky aminotroponate (AT) ligand is reported (DMAP = 4-(dimethylamino)pyridine). This compound was found to work as an excellent mononuclear main-group catalyst of the cyanosilylation of a variety of aldehydes and ketones. Loadings of 1 to 2 mol% of this catalyst consumed these substrates in just 5 to 30 min at room temperature.- Published
- 2017
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29. The Preparation of Complexes of Germanone from a Germanium μ-Oxo Dimer.
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Sinhababu S, Yadav D, Karwasara S, Sharma MK, Mukherjee G, Rajaraman G, and Nagendran S
- Abstract
Complexes of germanone containing formal Ge=O→M bonds (M=Zn, B, Ge, Sn) were isolated and characterized. The compounds were prepared through a novel synthetic route using a germanium μ-oxo dimer 3 as the starting material. This method circumvents the need to employ germanones to prepare complexes of germanones., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2016
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30. O,S-Heterocyclic stannylenes: synthesis and reactivity.
- Author
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Karwasara S, Jha CK, Sinhababu S, and Nagendran S
- Abstract
Commercially available N-oxide (2-mercaptopyridine-N-oxide) is used as a ligand instead of an oxidizing agent to stabilize the compounds of main group elements in low-valent states. The isolated compounds [(C5H4NOS)2Sn (), (C5H4NOS)SnCl () and (C5H4NOS)GeCl ()] are the first structurally characterized examples of O,S-heterocyclic stannylenes and germylenes with interesting bonding features. Further, the reaction of compound with SbCl3 afforded the rare dichlorodiantimony oxide [{(C5H4NOS)SbCl}2O] () unprecedentedly.
- Published
- 2016
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31. Digermylene Oxide Stabilized Group 11 Metal Iodide Complexes.
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Yadav D, Siwatch RK, Sinhababu S, Karwasara S, Singh D, Rajaraman G, and Nagendran S
- Abstract
Use of a substituted digermylene oxide as a ligand has been demonstrated through the isolation of a series of group 11 metal(I) iodide complexes. Accordingly, the reactions of digermylene oxide [{(i-Bu)2ATIGe}2O] (ATI = aminotroponiminate) (1) with CuI under different conditions afforded [({(i-Bu)2ATIGe}2O)2(Cu4I4)] (2) with a Cu4I4 octahedral core, [({(i-Bu)2ATIGe}2O)2(Cu3I3)] (3) with a Cu3I3 core, and [{(i-Bu)2ATIGe}2O(Cu2I2)(C5H5N)2] (4) with a butterfly-type Cu2I2 core. The reactions of compound 1 with AgI and AuI produced [({(i-Bu)2ATIGe}2O)2(Ag4I4)] (5) with a Ag4I4 octahedral core and [{(i-Bu)2ATIGe}2O(Au2I2)] (6) with a Au2I2 core, respectively. The presence of metallophilic interactions in these compounds is shown through the single-crystal X-ray diffraction and atom-in-molecule (AIM) studies. Preliminary photophysical studies on compound 6 are also carried out.
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- 2015
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32. Aminotroponiminato(chloro)germylene stabilized copper(I) iodide complexes: synthesis and structure.
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Yadav D, Siwatch RK, Sinhababu S, and Nagendran S
- Abstract
Reaction of an aminotroponiminato(chloro)germylene [(i-Bu)2ATIGeCl] (1) (ATI = aminotroponiminate) with CuI in acetonitrile afforded an aminotroponiminato(chloro)germylene stabilized copper(I) iodide complex [{(i-Bu)2ATIGeCl}2(Cu4I4)(CH3CN)2] (2) with a tetrameric distorted cubane type Cu4I4 core. The reaction of compound 1 in dichloromethane with CuI in the presence of 2 equiv of pyridine resulted in the first germylene stabilized copper(I) iodide complex [{(i-Bu)2ATIGeCl}(CuI)(C5H5N)2] (3) with a monomeric CuI core. A reaction of compound 1 with equimolar amounts of CuI and pyridine in dichloromethane resulted in a copper(I) iodide complex [{(i-Bu)2ATIGeCl}2(Cu2I2)(C5H5N)2] (4) with a dimeric Cu2I2 core. Interestingly, an interconversion between compounds 3 and 4 and conversion of compound 2 to compounds 3 and 4 under suitable conditions are also reported. The compounds 2-4 have been characterized by multinuclear NMR spectroscopy and single-crystal X-ray diffraction studies. The copper atoms in all these complexes are tetracoordinate, and the Ge(II)-Cu(I) bond lengths in complexes 2, 3, and 4 are 2.341(1), 2.308(1), and 2.345(1) Å, respectively.
- Published
- 2014
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33. Aminotroponiminatogermaacid halides with a Ge(E)X moiety (E = S, Se; X = F, Cl).
- Author
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Sinhababu S, Siwatch RK, Mukherjee G, Rajaraman G, and Nagendran S
- Abstract
Fluorination of aminotroponiminate (ATI) ligand-stabilized germylene monochloride [(t-Bu)(2)ATI]GeCl (1) with CsF gave the aminotroponiminatogermylene monofluoride [(t-Bu)(2)ATI]GeF (2). Oxidative addition reaction of compound 2 with elemental sulfur and selenium led to isolation of the corresponding germathioacid fluoride [(t-Bu)(2)ATI]Ge(S)F (3) and germaselenoacid fluoride [(t-Bu)(2)ATI]Ge(Se)F (4), respectively. Similarly, reaction of aminotroponiminatogermylene monochloride [(i-Bu)(2)ATI]GeCl (9) with elemental sulfur and selenium gave the aminotroponiminatogermathioacid chloride [(i-Bu)(2)ATI]Ge(S)Cl (11) and aminotroponiminatogermaselenoacid chloride [(i-Bu)(2)ATI]Ge(Se)Cl (12), respectively. Compound 9 has been prepared through a multistep synthetic route starting from 2-(tosyloxy)tropone 5. All compounds (2-4 and 6-12) were characterized through the multinuclear NMR spectroscopy, and single-crystal X-ray diffraction studies were performed on compounds 2, 4, and 8-12. The germaselenoacid halide complexes 4 and 12 showed doublet (-142.37 ppm) and singlet (-213.13 ppm) resonances in their (77)Se NMR spectra, respectively. Germylene monohalide complexes 2 and 9 have a germanium center in distorted trigonal pyramidal geometry, whereas a distorted tetrahedral geometry is seen around the germanium center in germaacid halide complexes 4, 11, and 12. The length of the Ge═E bond in germathioacid chloride (11) and germaselenoacid halide (4 and 12) complexes is 2.065(1) and 2.194(av) Å, respectively. Theoretical studies (based on the DFT methods) on complexes 4, 11, and 12 reveal the nature of the Ge═E multiple bond in these germaacid halide complexes with computed Wiberg bond indices (WBI) being 1.480, 1.508, and 1.541, respectively.
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- 2012
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34. Amelioration of root-knot disease of lady's finger plants by potentized Cina and Santonin.
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Sukul NC, Ghosh S, Sukul A, and Sinhababu SP
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- Animals, Homeopathy methods, Host-Parasite Interactions, Materia Medica, Meristem, Tylenchoidea drug effects, Antinematodal Agents pharmacology, Hibiscus, Pest Control, Biological methods, Plant Diseases parasitology, Plant Roots parasitology, Santonin pharmacology, Tylenchoidea physiology
- Abstract
Lady's finger plants (Hibiscus esculentus), grown in pots, were inoculated with the second-stage larvae (76+/-6) of root-knot nematodes Meloidogyne incognita, starting 7 days later they were treated with Cina 30c, Santonin 30c or Ethanol 30c by foliar spray for 10 consecutive days. The drugs in 90% ethanol were diluted with distilled water 1:1000 before application on plants. Thirty days after the last treatment the plants were uprooted. Cina 30c and Santonin 30c reduced nematode infestation of plants significantly in terms of root-gall number, root-protein content and nematode population in roots. Santonin 30c reduced root water content. Santonin 30c may have influenced the water channel proteins of root tissues thereby altering the water contents of roots. The reduced water content in roots might have adversely affected the root-knot nematodes and thus reduced nematode infestation. Ethanol 30c also has some effect on treated plants.
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- 2006
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35. Evaluation of psychopharmacological effects of petroleum ether extract of Cuscuta reflexa Roxb. stem in mice.
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Pal D, Panda C, Sinhababu S, Dutta A, and Bhattacharya S
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- Alkanes isolation & purification, Animals, Drug Evaluation, Preclinical methods, Female, Male, Mice, Motor Activity drug effects, Pain Measurement drug effects, Pain Measurement methods, Plant Extracts isolation & purification, Plant Extracts pharmacology, Plant Stems, Psychopharmacology, Sleep drug effects, Alkanes pharmacology, Cuscuta
- Abstract
The petroleum ether extract of Cuscuta reflexa Roxb. stem (PECR) was evaluated for its psychopharmacological activities in several experimental models using Swiss albino mice. The PECR was found to cause significant reduction in spontaneous activity and exploratory behavioral profiles. It also showed reduction in muscle relaxant activity by rotarod, 30 degrees inclined screen tests and showed significant analgesic properties as well as potentiated remarkably the pentobarbitone sodium, diazepam and meprobamate--induced sleeping time. All these results were compared with respective controls for the evaluation of significance. The presence of steroids in the PECR might he responsible for psychopharmacological activities.
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- 2003
36. Potentized Mercuric chloride and Nux vomica facilitate water permeability in erythrocytes of a fresh-water catfish Clarius batrachus under acute ethanol intoxication.
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Sukul NC, De A, Sinhababu SP, and Sukul A
- Subjects
- Alcoholic Intoxication drug therapy, Analysis of Variance, Animals, Catfishes, Disease Models, Animal, Erythrocytes metabolism, Humans, In Vitro Techniques, Intracellular Membranes drug effects, Permeability drug effects, Alcoholic Intoxication metabolism, Erythrocytes drug effects, Fresh Water chemistry, Homeopathy methods, Mercuric Chloride pharmacology, Plant Extracts pharmacology, Strychnos nux-vomica
- Abstract
Objectives: The primary biomolecular target of a homeopathic potency is unknown. If it is a plasma membrane protein such as water-channel protein, the drug would alter water permeation in cells. Therefore, the objective is to see if potentized homeopathic drugs like Mercuric chloride 30c and Nux vomica 30c could alter permeation of water through the erythrocytes of a fresh water fish under acute ethanol intoxication., Location: The work was carried out in the Zoology Laboratory of Visva Bharati University, Santiniketan, West Bengal, India., Subject: Live freshwater catfish., Design: Erythrocytes collected from fish with and without ethanol intoxication were incubated in distilled water at 30 degrees C for 30 minutes with Ethanol 30c (control), Merc cor 30c (test 1), and Nux vomica 30c (test 2). Merc cor 30c and Nux vom 30c were prepared by successive dilution of the respective mother tinctures with 90% ethanol (1:100) followed by sonication at 20 kHz for 30 seconds in 30 steps. Ethanol 30c was prepared in the same way from 90% ethanol diluted with 90% ethanol. In another experiment, fish were pretreated with Ethanol 30c and Nux vom 30c followed by ethanol injection at 2 g/kg of body weight. Then their erythrocytes were tested in vitro with the same potencies. After centrifugation of blood samples, fluid part was removed, erythrocyte pellets dried in a BioChemical Oxygen Demand (BOD; Atlas Surgical, New Delhi, India) incubator at 90 degrees C for 12 hours and intracellular water content measured., Results: Red blood cells (RBCs) from ethanol-injected fish permeated more water than those from normal fish. Water permeation was enhanced with Merc cor 30c and Nux vom 30c. RBCs from fish pretreated with Nux vom 30c imbibed more water in in vitro treatments than those from fish pretreated with Ethanol 30c., Conclusion: Because water channel proteins or aquaporins are mainly responsible for water transport through the plasma membrane of RBCs, it is thought that potentized drugs interact with these proteins, thereby facilitating water influx in the cells.
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- 2003
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37. Potentized Mercuric chloride and Mercuric iodide enhance alpha-amylase activity in vitro.
- Author
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Sukul NC, De A, Sukul A, and Sinhababu SP
- Subjects
- Ethanol, Humans, In Vitro Techniques, Starch, Time Factors, Water, alpha-Amylases drug effects, Disinfectants pharmacology, Homeopathy, Iodides pharmacology, Mercuric Chloride pharmacology, Mercury Compounds pharmacology, alpha-Amylases metabolism
- Abstract
Mercuric chloride 30c and Mercuric iodide 30c were prepared by successive dilution in 30 steps of 1:100 followed by sonication at 20KHz for 30s at each step. Both were prepared in two media: 90% ethanol and distilled water. Three preparations of Mercuric chloride 30 in water were used: 12-month old, 1-month old and 4-day old. The controls for the water and ethanol-water preparations were pure water 30c and 90% ethanol 30c, respectively. For the three water preparations there were three matched controls of water 30c of the same ages. Each potentized substance or its control was mixed with distilled water 1:100 before testing. Hydrolysis of starch by alpha-amylase was measured by the standard procedure after incubation for 15 min at 27 degrees C. Mercuric chloride 30c and Mercuric iodide 30c in both water and aqueous ethanol media, enhanced enzyme activity significantly, compared to their respective controls. Mercuric chloride 30c, prepared in water 12 months previously, produced no significant change in the enzyme activity compared to its control. We hypothesize that the structure of the active molecule imprinted on water polymers during the process of dynamization. The specifically structured water interacts with the active sites of alpha-amylase, modifying its activity. Ethanol molecules have large non-polar part stabilizing the water structure and thus retaining activity for a longer time.
- Published
- 2002
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38. Nux vomica 30 prepared with and without succession shows antialcoholic effect on toads and distinctive molecular association.
- Author
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Sukul NC, De A, Dutta R, Sukul A, and Sinhababu SP
- Subjects
- Administration, Oral, Animals, Bufonidae, Infrared Rays, Magnetic Resonance Spectroscopy, Ethanol antagonists & inhibitors, Materia Medica administration & dosage, Materia Medica pharmacology, Reflex drug effects, Sleep drug effects, Strychnine administration & dosage, Strychnine pharmacology
- Abstract
Adult toads, Bufo melanostictus, were administered Nux vomica (Nux v) 30 prepared with and without succussion on the tongue. The drug was mixed with sterile distilled water at the rate 0.05ml/ml water and given orally 0.05ml/individual. The control consisted of blank ethanol solution. Seeds of Strychnos nuxvomica were ground and extracted with 90% ethanol in the laboratory. Nux v 30 was prepared by successive dilution and succussion in 30 steps, Nux v 30 u was prepared by successive dilution only. Four hours after treatment, toads were given 25% ethanol i.p. at 8g/kg body weight. The duration of ethanol induced sleep time was recorded for each toad. Both Nux v 30 and Nux v 30 u significantly reduced ethanol induced sleep time in toads as compared to their respective controls. Electronic, infra red and nuclear magnetic resonance spectra of Nux v 30, Nux v 30 u and their diluent medium (90% ethanol) show marked differences from each other. These dilutions and ethanol 30 and ethanol 30 u show marked differences from each other with respect to spin-lattice relaxation time (T1) and chemical shift. The difference has been attributed to the variation in intra and inter-molecular association of ethanol and water.
- Published
- 2001
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39. Strychnos nux-vomica extract and its ultra-high dilution reduce voluntary ethanol intake in rats.
- Author
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Sukul NC, Ghosh S, Sinhababu SP, and Sukul A
- Subjects
- Alcohol Deterrents therapeutic use, Alcoholism prevention & control, Animals, Disease Models, Animal, Ethanol, Plant Extracts pharmacology, Plant Extracts therapeutic use, Rats, Strychnine therapeutic use, Alcohol Deterrents pharmacology, Feeding Behavior drug effects, Homeopathy, Plants, Medicinal, Strychnine pharmacology
- Abstract
Objectives: To see whether Strychnos nux-vomica extract (mother tincture [MT]), its potency Nux 30c, and its principal alkaloid, strychnine, could reduce voluntary ethanol intake in rats. To analyze the solution structure of Nux MT, Nux 30c, 90% ethanol, and ethanol 30c by means of electronic (ES) and nuclear nuclear magnetic resonance (NMR) spectra., Design: Potentially alcoholic rats were first given 20% ethanol and then kept on a two-choice bottle, one with 20% ethanol and another with tap water. These rats were given the following oral treatments for 15 days: group 1, control; group 2, strychnine at 0.36 mg/kg per day; group 3, ethanolic extract of S. nux-vomica seeds (Nux MT) at 3.6 mg/kg per day; and group 4, Nux 30c at 0.05 mL/d per rat. Nux 30c was prepared by successive dilution of Nux MT and 90% ethanol (1:100) and sonication at 20 kHz for 30 seconds in 30 steps., Results: Both Nux MT and Nux 30c significantly reduced ethanol intake and increased water intake in rats. ES of two dilutions of Nux MT and Nux 30c showed intersections at more than one point suggesting existence of molecular complexes. ES of Nux MT in CCl4 showed a red shift when 90% ethanol was added indicating molecular complexation and charge transfer interaction between ethanol and Nux compounds. NMR spectra of Nux MT, 90% ethanol, ethanol 30c, and Nux 30c indicated a change in solution structure of the medium (90% ethanol) of Nux 30c., Conclusion: Nux MT and Nux 30c could reduce ethanol intake in rats. The altered solution structure of Nux 30c is thought to mimic Nux MT and produce ethanol aversion in rats.
- Published
- 2001
- Full Text
- View/download PDF
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