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1.
Inorg Chem ; 61(25): 9392-9404, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35706334

RESUMO

The synthesis and structure of lithium, magnesium, and zinc complexes N,N'-chelated by a hybrid amine-amido ligand ([2-(Me2NCH2)C6H4NR]-, abbreviated as LNR, where R = H, SiMe3, or Bn) are reported. The reaction of the least sterically demanding LNH with various magnesium sources gives the hexameric imide [LNMg]6 (4) by the elimination of n-butane from LNHMgnBu (2) or by the reaction of LNHLi (1) with MeMgBr. [LNH]2Mg (3) is obtained through the addition of 0.5 equiv of nBu2Mg or Mg[N(SiMe3)2]2 to LNH2 and with 1 equiv of nBu2Mg reacting to 2. Both LNHMgN(SiMe3)2 (6) and isostructural LNHZnN(SiMe3)2 (16) have been prepared using two different approaches: monodeprotonation of LNH2 by Zn/Mg[N(SiMe3)2]2 in a 1:1 ratio or ligand substitution of 2 or LNHZnEt (12) by 0.5 equiv of Sn[N(SiMe3)2]2. The reactions of 2 or 3 with 1 provide the heterotrimetallic complex [LNH]4Li2Mg (5). Benzyl- or trimethylsilyl-substituted anilines [LN(SiMe3)H (7) and LN(Bn)H (8)] with 0.5 equiv of nBu2Mg allow the formation of homoleptic bis(amides) of the [LN(R)]2Mg type (10 and 11). Nevertheless, only the silylated secondary amine 7 is able to provide the heteroleptic n-butylmagnesium amide LN(SiMe3)MgnBu (9) upon reaction with an equimolar amount of nBu2Mg. Similarly, 12, [LNH]2Zn (13), LN(R)ZnEt (17 and 18), and [LN(R)]2Zn [R = SiMe3 (19) and Bn (20)] were prepared by the monodeprotonation of LNH2 or LN(R)H using Et2Zn in the corresponding stoichiometric ratio. LNHZnI was prepared by the nucleophilic substitution of an ethyl chain in 12 by molecular iodine. A heterometallic complex, [LNH]4Li2Zn (14), analogous to 5 was prepared from 12 or 13 with 1 or 2 equiv of 1, respectively.

2.
Inorg Chem ; 60(12): 8428-8431, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34101456

RESUMO

The electrophilic substitution of icosahedral closo-1-SB11H11 with methyl iodide has resulted in two B-functionalized thiaboranes, 7,12-I2-2,3,4,5,6,8,9,10,11-(CH3)9-1-closo-SB11 and 7,8,12-I3-2,3,4,5,6,9,10,11-(CH3)8-closo-1-SB11, with the former being significantly predominant. These two icosahedral thiaboranes are the first cases of polysubstituted polyhedral boron clusters with another vertex that differs from B and C. Such polyfunctionalizations have increased the earlier observed thiaborane icosahedral barrier, not exhibiting any reactivity toward bases, unlike the parent thiaborane. The search for methylation pathways has revealed that the complete B11-methylation is impossible, like in the case of decaborane(14), where this seems to be a result of the positively charged upper parts of these two molecules.

3.
Chemistry ; 26(40): 8698-8702, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32297684

RESUMO

Spin-orbit (SO) heavy-atom on the light-atom (SO-HALA) effect is the largest relativistic effect caused by a heavy atom on its light-atom neighbors, leading, for example, to unexpected NMR chemical shifts of 1 H, 13 C, and 15 N nuclei. In this study, a combined experimental and theoretical evidence for the SO-HALA effect transmitted through hydrogen bond is presented. Solid-state NMR data for a series of 4-dimethylaminopyridine salts containing I- , Br- and Cl- counter ions were obtained experimentally and by theoretical calculations. A comparison of the experimental chemical shifts with those calculated by a standard DFT methodology without the SO contribution to the chemical shifts revealed a remarkable error of the calculated proton chemical shift of a hydrogen atom that is in close contact with the iodide anion. The addition of the relativistic SO correction in the calculations significantly improves overall agreement with the experiment and confirms the propagation of the SO-HALA effect through hydrogen bonds.

4.
Chemistry ; 26(40): 8669, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32530077

RESUMO

Invited for the cover of this issue is the group of Michal Straka and Martin Dracínský (IOCB Prague, Czech Academy of Sciences). The image depicts a neutron star, which is used to represent the relativistic effects between a heavy element and a hydrogen atom reported in this work. Read the full text of the article at 10.1002/chem.202001532.

5.
Chemistry ; 26(69): 16541-16553, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-32757220

RESUMO

Carbonic anhydrase IX (CA IX), a tumor-associated metalloenzyme, represents a validated target for cancer therapy and diagnostics. Herein, we report the inhibition properties of isomeric families of sulfonamidopropyl-dicarba-closo-dodecaboranes group(s) prepared using a new direct five-step synthesis from the corresponding parent cages. The protocol offers a reliable solution for synthesis of singly and doubly substituted dicarba-closo-dodecaboranes with a different geometric position of carbon atoms. The closo-compounds from the ortho- and meta-series were then degraded to corresponding 11-vertex dicarba-nido-undecaborate(1-) anions. All compounds show in vitro enzymatic activity against CA IX in the low nanomolar or subnanomolar range. This is accompanied by clear isomer dependence of the inhibition constant (Ki ) and selectivity towards CA IX. Decreasing trends in Ki and selectivity index (SI ) values are observed with increasing separation of the cage carbon atoms. Interactions of compounds with the active sites of CA IX were explored with X-ray crystallography, and eight high-resolution crystal structures uncovered the structural basis of inhibition potency and selectivity.


Assuntos
Antígenos de Neoplasias/química , Anidrase Carbônica IX/química , Anidrase Carbônica I/química , Inibidores da Anidrase Carbônica , Neoplasias , Antígenos de Neoplasias/metabolismo , Anidrase Carbônica I/metabolismo , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/farmacologia , Humanos , Isoenzimas , Relação Estrutura-Atividade
6.
Inorg Chem ; 59(23): 17430-17442, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33197177

RESUMO

Herein, we describe the synthesis of two families of compounds accessible from [3 + 2] cycloaddition reactions of known B8-substituted isonitrilium and new C1-alkylnitrile and C(1,1')-dialkylnitrile derivatives of the [(1,2-C2B9H11)2-3,3'-Co(III)]- ion with an azide ion that produce a tetrazole ring substitution at the cobaltacarborane cage. In addition, we outline the important differences in reactivity observed for the two types [B-isonitrilium/C-(alkyl)nitrile] of cobaltacarborane derivatives. The first family of compounds described corresponds to C5-atom-boronated tetrazole rings, with the five-membered moiety in the second type being doubly substituted at the N1 and C5 positions. This substitution opens cobaltacarborane chemistry to a new type of functional group at the cage of potential utility as structural blocks for use in medicinal chemistry or materials science. Our study includes single-crystal X-ray structures of the starting nitriles and both families of tetrazole derivatives, and the structural features that arise from the substitutions are discussed.

7.
Inorg Chem ; 59(15): 10540-10547, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32662985

RESUMO

The paper reports specific syntheses of methylated decaborane(14), nido-B10H14 (1), derivatives. The reaction of 1 with an excess of neat MeI and AlCl3 yields 1,2,3,4-Me4-nido-B10H10 (2) essentially quantitatively when performed at room temperature. Heating the same mixture to 120 °C provides 1-I-2,3,4,5,7,8,10-Me7-nido-B10H6 (3a). The formation of analogous 1-CF3SO2O-2,3,4,5,7,8,10-Me7-nido-B10H6 (3b) is achieved by heating 1 or 2 with an excess of MeSO3CF3 in the presence of a catalytic amount of HOSO2CF3 to 120 °C. Compounds 2 and 3 can be deprotonated to yield the corresponding anions [1,2,3,4-Me4-nido-B10H9]- (2-), [1-I-2,3,4,5,7,8,10-Me7-nido-B10H5]- (3a-), and [1-CF3SO2O-2,3,4,5,7,8,10-Me7-nido-B10H5]- (3b-). The structure of all the compounds isolated has been unambiguously confirmed by multinuclear (11B and 1H) NMR measurements, and the structures of 2-, 3a, 3a-, and 3b have been established by X-ray diffraction analyses. The very high volatility of 2 has made it impossible to apply X-ray diffraction in this case; therefore, its structure has been derived computationally using the ab initio/GIAO/NMR tool. DFT-based computational protocols have also outlined the reason why it is impossible to obtain an octamethyl derivative of 1 experimentally.

8.
Inorg Chem ; 59(15): 10854-10865, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32650639

RESUMO

Comparative studies of the synthesis of lithium guanidinates via nucleophilic addition of lithium amides to carbodiimides were performed. Four combinations of small or sterically crowded carbodiimide and sterically crowded lithium amide or lithium amide containing an adjacent amino donor group give ten different types of complexes. In particular, 2,6-[(CH3)2CH]2C6H3NHLi (DipNHLi, 1) reacts with (CH3)2CHN═C═NCH(CH3)2 upon the formation of the dissymmetric dimeric complex 2 with four-coordinate Li atoms. In contrast, 1 with DipN═C═NDip gives the mononuclear lithium guanidinate 3 with two-coordinate lithium by κ1-guanidinate, solvent molecule, and additional interaction with a π-electron cloud of one of the Dip groups. Analogous reactions of 2-[(CH3)2NCH2]C6H4NHLi (7) yield complexes 8 and 9, where the adjacent amino donors are always coordinated. Further deprotonation of 2, 3, 8, and 9 leads to dilithium guanidinates(2-)-4, 5, 10, and 11, among which only 5, containing three Dip groups, is monomeric with contacts to two π-electron systems of Dip groups. The rest of the complexes are tetranuclear with different structural patterns. In the central parts of molecules, toward which the nitrogen atoms of the guanidinates are oriented, lithium atoms are usually pseudotetrahedral, but trigonal in peripheral parts. Adjacent solvent molecules, chelating amino groups, and π-electron systems of Dip groups are coordinated in order to complete coordination polyhedra. Complexes 4 and 5 deoligomerize in solution upon the formation of fluxional monomeric dilithium species. Conversely, 11 is a dimer in solution due to the strong donation of an amino group. The silylated lithium amide {2-[(CH3)2NCH2]C6H4}[(Si(CH3)3]NLi (12) reacts with both carbodiimides to give dinuclear 13 obtained from diisopropylcarbodiimide and monomeric 14 from the second carbodiimide. Complexes 13 and 14 structurally resemble 8 and 9, with the highest degree of the localization of π-electron density within the N3C guanidinate system, η3-contact to the Dip ring, and a lack of the solvent molecule in 14.

9.
Molecules ; 25(4)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069968

RESUMO

Ring cleavage of cyclic ether substituents attached to a boron cage via an oxonium oxygen atom are amongst the most versatile methods for conjoining boron closo-cages with organic functional groups. Here we focus on much less tackled chemistry of the 11-vertex zwitterionic compound [10-(O-(CH2-CH2)2O)-nido-7,8-C2B9H11] (1), which is the only known representative of cyclic ether substitution at nido-cages, and explore the scope for the use of this zwitterion 1 in reactions with various types of nucleophiles including bifunctional ones. Most of the nitrogen, oxygen, halogen, and sulphur nucleophiles studied react via nucleophilic substitution at the C1 atom of the dioxane ring, followed by its cleavage that produces six atom chain between the cage and the respective organic moiety. We also report the differences in reactivity of this nido-cage system with the simplest oxygen nucleophile, i.e., OH-. With compound 1, reaction proceeds in two possible directions, either via typical ring cleavage, or by replacement of the whole dioxane ring with -OH at higher temperatures. Furthermore, an easy deprotonation of the hydrogen bridge in 1 was observed that proceeds even in diluted aqueous KOH. We believe this knowledge can be further applied in the design of functional molecules, materials, and drugs.


Assuntos
Boranos/química , Dioxanos/química , Halogênios/química , Boro/química , Nitrogênio/química , Temperatura
10.
Molecules ; 25(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155946

RESUMO

Although 1-Ph-2-X-closo-1,2-C2B10H10 (X = F, Cl, Br, I) derivatives had been computed to have positive values of the heat of formation, it was possible to prepare them. The corresponding solid-state structures were computationally analyzed. Electrostatic potential computations indicated the presence of highly positive σ-holes in the case of heavy halogens. Surprisingly, the halogen•••π interaction formed by the Br atom was found to be more favorable than that of I.


Assuntos
Compostos de Boro/química , Carbono/química , Halogênios/química , Compostos de Boro/síntese química , Técnicas de Química Sintética , Halogenação , Modelos Moleculares , Conformação Molecular
11.
Inorg Chem ; 58(4): 2471-2482, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30729783

RESUMO

The 12-X- closo-SB11H10 (X = H or I) thiaboranes react with one or two molar equivalents of various N-heterocyclic carbenes (NHCs) to give the deprotonated 12-vertex species of [12-X-SB11H9·NHC]-[NHC-H]+composition as kinetic products. The use of one molar equivalent of a sterically more hindered NHC reactant leads to the formation of 12-X-SB11H10·NHC adducts with a heavily distorted cage and the nido electron count. Further reaction of 12-I-SB11H10·NHC to deboronated 12-X-SB10H9·NHC proceeds in acetone to complete the closo- nido reaction pathway under the thermodynamic control. The structures of all compounds have been investigated by NMR spectroscopy and diffraction techniques. The results are supported by theoretical methods.

12.
Inorg Chem ; 58(4): 2865-2871, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30730720

RESUMO

Methyl-camouflaged dicarbaboranes closo-1,2- and 1,10-H2C2B8Me8 have been prepared in high yields either from nido-5,6-H2C2B8H10 or closo-1,2-H2C2B8H8 via electrophilic methylation reactions and cluster-rearrangement methods. Prepared were also monosubstituted derivatives of general formulation closo-H2C2B8Me7-X (X = I or OTf). The permethylated compounds exhibit extreme air stability in comparison to unprotected counterparts as a consequence of rigid, egg-shaped hydrocarbon structures incorporating inner C2B8 carborane scaffolding. The structures of all compounds isolated were confirmed unambiguously by multinuclear (11B, 1H, 13C, and 19F) NMR measurements, supported by X-ray diffraction analyses and geometry optimization methods on several compounds.

13.
Chemistry ; 24(54): 14470-14476, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30016544

RESUMO

Studies have been focused on the synthesis of N→Ga-coordinated organogallium selenides and tellurides [L1 Ga(µ-Se)]2 (1), [L2 Ga(µ-Se)]2 (2) and [L1 Ga(µ-Te)]2 (3), respectively, containing either N,C,N- or C,N-chelating ligands L1, 2 (L1 is {2,6-(Me2 NCH2 )2 C6 H3 }- and L2 is {2-(Et2 NCH2 )-4,6-tBu2 -C6 H2 }- ) having Ga/E (E=Se or Te) atoms in 1/1 ratio. To change the Ga/E ratio, an unusual N→Ga-coordinated organogallium tetraselenide L1 Ga(κ2 -Se4 ) (4) was prepared. An unprecedented complex (L1 Ga)2 (µ-Te2 )(µ-Te) (5), as the result of the non-stability of 3, was also isolated. Compound 2 is a suitable single-source precursor for the preparation of amorphous GaSe thin films by the spin coating. Moreover, simple heating of an octadecylamine solution of 2 provided, after work up, monoclinic Ga2 Se3 crystals with different crystallinity according to conditions used. Therefore, compound 2 may be also used as a source of Ga2 Se3 in the low-temperature doping process of Bi2 Se3 .

14.
Chemistry ; 23(13): 3074-3083, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28052458

RESUMO

Treatment of the neutral pyridine-based ligands L1 -L3 , bearing either one or two RN=CH imine moieties {where L1 and L2 are N,N-chelating ligands 2-(RN=CH)C5 H4 N (R=Ph (L1 ) or R=2,4,6-Ph3 C6 H2 (L2 )) and L3 is the N,N,N-chelating ligand 2,6-(RN=CH)2 C5 H3 N (R=2,6-iPr2 C6 H3 )}, with HSiCl3 yielded N→Si-coordinated silicon(IV) amides 2-{Cl3 SiN(R)CH2 }C5 H4 N (1, R=Ph; 2, R=2,4,6-Ph3 C6 H2 ) and 2-{Cl3 SiN(R)CH2 }-6-(RN=CH)C5 H4 N (3, R=2,6-iPr2 C6 H3 ). The organosilicon amides 1-3 are the products of spontaneous hydrosilylation of the RN=CH imine moiety induced by N→Si coordination of the proposed N,N-chelated chlorosilanes L1 →SiHCl3 (1 a), L2 →SiHCl3 (2 a), and L3 →SiHCl3 (3 a). Furthermore, the reaction of L3 with an excess of HSiCl3 provided the intramolecularly coordinated chlorosilicon diamide cyclo-{(C5 H3 N)-1,3-(CH2 NR)2 }SiCl2 (4) (R=2,6-iPr2 C6 H3 ) as the product of spontaneous reduction of both RN=CH imine moieties. The compounds have been characterized by NMR spectroscopy (1-4) and single-crystal X-ray diffraction analysis (1, 3, and 4). The mechanism of the hydrosilylation of the second RN=CH imine moiety in 3 by an excess of SiHCl3 has also been studied. The experimental work is supplemented by DFT calculations.

15.
Inorg Chem ; 56(10): 5971-5975, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28467047

RESUMO

Initial studies on electrophilic halogenation of the dicarbaborane closo-1,2-C2B8H10 (1) have been carried out to reveal that the substitution takes place at B7 and B10 vertexes, which are the most removed from the CH positions. The course of the halogenation is strongly dependent on the nature of the halogenation agent and reaction conditions. Individual reactions led to the isolation of the monosubstituted compounds 1,2-C2B8H9-10-X (2) (where X = F, I) and 1,2-C2B8H9-7-X (3) (where X = Cl, I). Disubstituted carboranes 1,2-C2B8H8-7,10-X2 (4) (where X = Cl, Br, I) were obtained under more forcing conditions. Individual halo derivatives were characterized by mass spectrometry and high-field NMR (11B, 1H,13C) spectroscopy combined with two-dimensional [11B-11B]-COSY, 1H{11B(selective)}, and [11B-1H]-correlation NMR techniques. All of the derivatives bearing a halogen substituent in the B10 position exhibit a remarkable antipodal 13C and 1H NMR shielding at the CH1 vertex, increasing in the order H < I < Br < Cl < F. The structures of 1,2-C2B8H8-7,10-X2 derivatives (where X = Cl, I, 4b,d) were established by X-ray diffraction analyses.

16.
Chemphyschem ; 17(21): 3373-3376, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27595561

RESUMO

Halogen bonds are a subset of noncovalent interactions with rapidly expanding applications in materials and medicinal chemistry. While halogen bonding is well known in organic compounds, it is new in the field of boron cluster chemistry. We have synthesized and crystallized carboranes containing Br atoms in two different positions, namely, bound to C- and B-vertices. The Br atoms bound to the C-vertices have been found to form halogen bonds in the crystal structures. In contrast, Br atoms bound to B-vertices formed hydrogen bonds. Quantum chemical calculations have revealed that halogen bonding in carboranes can be much stronger than in organic architectures. These findings open new possibilities for applications of carboranes, both in materials and medicinal chemistry.

17.
Inorg Chem ; 55(20): 10122-10124, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27661091

RESUMO

Reported is an unusual tautomeric behavior within the [nido-5,6-C2B8H11]- (1a-) cage that has no precedence in the whole area of carborane chemistry. Isolated were two skeletal tautomers, anions [6-Ph-nido-5,6-C2B8H10-µ8,9]- (2d-) and [5,6-Me2-nido-5,6-C2B8H9-µ9,10]- (3b-), which differ in the positioning of the open-face hydrogen bridge. Their structures have been determined by X-ray diffraction analyses. The 3b-structure is stabilized by intermolecular interaction involving Et3NH+ and B8-B9 and H8 atoms in the solid phase; however, its dissolution in CD3CN causes instant conversion to the more stable [5,6-Me2-nido-5,6-C2B8H9-µ8,9]- (2b-) tautomer. The dynamic electron-correlation-based MP2/6-31G* computations suggest that the parent [nido-5,6-C2B8H11-µ8,9]- (2a-) tautomer is 3.9 kcal·mol-1 more stable than the [nido-5,6-C2B8H11-µ9,10]- (3a-) counterpart and the µ8,9 structure 2- is therefore the most stable tautomeric form in the solution, as was also demonstrated by multinuclear (1H, 11B, and 13C) NMR measurements on the whole series of C-substituted compounds.

18.
Inorg Chem ; 55(14): 7068-74, 2016 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-27351461

RESUMO

Sequential methylation of arachno-6,9-C2B8H14 (1) led to a series of methyl derivatives and finally to the camouflaging of all boron positions by mixed persubstitution. Thus, deprotonation of 1 produced the [arachno-6,9-C2B8H13] anion (1(-)), the methylation of which with MeI in tetrahydrofuran proceeded on the open-face boron vertexes with the formation of 5-Me-arachno-6,9-C2B8H13 (2; yield 28%) and 5,8-Me2-arachno-6,9-C2B8H12 (3; yield 36%). Observed in this reaction was also a side formation of 2-Me-closo-1,6-C2B8H9 (4; yield 6%).The electrophilic AlCl3-catalyzed CH3(+) attack of the neutral 1 in neat MeI at ambient temperature afforded 1,3-Me2-arachno-6,9-C2B8H12 (5), while a 76-h heating at 120 °C generated a mixture of the di- and triiodo derivatives 1,2,3,4,8,10-Me6-5,7-I2-arachno-6,9-C2B8H6 (6) and 1,2,3,4,7-Me5-5,7,10-I3-arachno-6,9-C2B8H6 (7). On the other hand, a HOTf-catalyzed reaction between 1 and MeOTf at reflux resulted in the isolation of 2-TfO-1,3.4,5,7,8,10-Me7-arachno-6,9-C2B8H6 (8; Tf = CF3SO2; yield 65%). The compounds were characterized by multinuclear ((11)B, (1)H, (13)C, and (19)F) NMR spectroscopy, mass spectrometry, and elemental analysis, and the structures of compounds 1, 1(-), 5, and 6 were established by X-ray diffraction analysis.

19.
Bioorg Med Chem ; 24(7): 1560-72, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26947959

RESUMO

In the current study, sixteen novel derivatives of (R)-1-(6-fluorobenzo[d]thiazol-2-yl)ethanamine were synthesized as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. Chemical structures together with purity of the synthesized compounds were substantiated by IR, (1)H, (13)C, (19)F NMR, high resolution mass spectrometry and elemental analysis. The optical activities were confirmed by optical rotation measurements. The synthesized compounds were evaluated for their AChE and BChE inhibitory activities. In addition, the cytotoxicity of the most active compounds was investigated against human cell lines employing XTT tetrazolium salt reduction assay and xCELLigence system allowing a label-free assessment of the cells proliferation. Our results demonstrated that the inhibitory mechanism was confirmed to be pseudo-irreversible, in line with previous studies on carbamates. Compounds indicated as 3b, 3d, 3l and 3n showed the best AChE inhibitory activity of all the evaluated compounds and were up to tenfold more potent than standard drug rivastigmine. The binding mode was determined using state-of-the-art covalent docking and scoring methodology. The obtained data clearly demonstrated that 3b, 3d, 3l and 3n benzothiazole carbamates possess high inhibitory activity against AChE and BChE and concurrently negligible cytotoxicity. In conclusion, our results indicate, that these derivatives could be promising in an effective therapeutic intervention for Alzheimer's disease.


Assuntos
Acetilcolinesterase/metabolismo , Benzotiazóis/farmacologia , Butirilcolinesterase/metabolismo , Carbamatos/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Simulação de Acoplamento Molecular , Benzotiazóis/síntese química , Benzotiazóis/química , Carbamatos/síntese química , Carbamatos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/síntese química , Relação Dose-Resposta a Droga , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células Jurkat , Estrutura Molecular , Relação Estrutura-Atividade
20.
Inorg Chem ; 54(14): 6792-800, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26114305

RESUMO

The syntheses of the compounds [L(1)SnCl][M(CO)5(SnCl3)] (3, M = W; 4, M = Cr), [L(1)SnCl]OTf (5), [L(1)SnCl][W(CO)5(SnCl2OTf)] (6), [L(1)SnOTf][OTf] (7), and [L(2)Sn(OTf)2] (8) with L(1) = {2,6-[(CH3)C═N(C6H3-2,6-(i)Pr2)2]C5H3N} (DIMPY) and L(2) = {2-[(CH3)C═N(C6H3-2,6-(i)Pr2)]-6-(CH3O)}C5H3N) is reported. The compounds were characterized by elemental analyses, (1)H, (13)C, (19)F, and (119)Sn NMR spectroscopy, electrospray ionization mass spectrometry, and single-crystal X-ray diffraction analyses (3·1.5C7H8, 5·CH2Cl2, 7·C7H8, 8). For compounds 7 and 8, the experimental work is accompanied by density functional theory calculations.

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