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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123939, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38301569

RESUMO

The VCD spectra of chiral 2,3-dihydro-1H-benzo[de]isoquinolin-1-one (8-substituted naphthalene-1-carboxamide, BIQ) were studied in KBr pellets. The X-ray diffractometry revealed that the Me, Ph, and pClPh BIQs crystalize in the monoclinic P21, while nBu, pMePh, and oMeOPh BIQs in the orthorhombic P212121 space group. Only the Me-BIQ crystal exhibits the presence of cyclic amide dimers, while the others contain chains of the amid group hydrogen bonds. For all BIQs, except pMePh, the most intense IR band in the 1750-1550 cm-1 region is located at ca. 1680 cm-1 and is accompanied by two weak ones at ca. 1618 and 1590 cm-1. For the pMePh derivative, four almost equally intense IR bands at 1662, 1639, 1614, and 1588 cm-1 are observed. This region of the IR spectra of BIQs, but pMePh, is well reproduced by calculations based on BIQ monomers. On the other hand, the complex IR pattern of pMePh is computationally reproduced when larger crystal fragments, like octamers, are considered. Registration of the VCD spectra enabled recognizing the complexity of IR contours at ca. 1680 cm-1 by the corresponding VCD motives. For (i) Me, Ph and pClPh (R)-enantiomers, two (+)(-) bands were distinguished and for (ii) nBu and pMePh ones, one VCD band with right-side asymmetry was found. For (iii) oMeOPh the VCD pattern cannot be unambiguously assigned. Thus, the VCD spectra in the ν(C=O) range diverse the studied compounds. Among the set of molecules, pMePh has exceptional crystal geometry. Therefore, its most intense ν(C=O) band position and shape can be connected with the geometry of the hydrogen bonds, interactions, and crystal packing. Interpretation of the VCD spectra is based on linear and packed BIQ octamers. This cluster model can reproduce the main features of the solid-state VCD of BIQs.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122089, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36436264

RESUMO

The UV-vis and ECD spectroelectrochemistry (SEC) of a chiral binaphthalenylamine derivative of the N-butyl naphthalenediimide (NDIB-NH2) enantiomers were applied to measure UV-vis and ECD spectra of NDIB-NH2 radicals and dianion formed in the reduction and oxidation processes observed in cyclic voltammetry (CV). The CV curves and EPR spectroelectrochemistry enabled us to establish conditions at which a radical-anion [NDIB-NH2]̇.-, a dianion [NDIB-NH2]2-, and a radical-cation [NDIB-NH2]̇.+ are formed. The DFT restricted open-shell CAM-B3LYP-D3/def2TZVP/PCM calculations demonstrated that in the radical-anion [NDIB-NH2]̇.-, spin is spread over the NDI system while in the radical-cation [NDIB-NH2]̇+ it is spread over the aminonaphthalene moiety. The UV-vis spectra of radical-anion and dianion show the most significant changes in the 400-800 nm range. In that range, the ECD spectra varied with the change of electrode potential more than the UV-vis did and enabled the identification of a new ECD band of [NDIB-NH2]̇.- at ca. 400 nm hidden in the background in the UV spectra at -1000 mV. A broad structured ECD pattern with a maximum at ca. 530 nm was observed for [NDIB-NH2]̇.- (-1000 mV), while a single smooth ECD band of [NDIB-NH2]2- was located at 520 nm (-1750 mV). For the first time, an isosbestic point (455 nm) was found in ECD spectroelectrochemical measurements for the radical-cation [NDIB-NH2]̇.+ in equilibrium with the NDIB-NH2 neutral form. The TD-DFT CAM-B3LYP-D3/6-31G** calculations combined with the hybrid (explicit combined with implicit) solvation model fairly well reproduced the UV-vis and ECD SEC of neutral and redox forms of NDIB-NH2 but the ECD spectrum of [NDIB-NH2]̇.+ above 390 nm.


Assuntos
Teoria da Densidade Funcional , Oxirredução , Ânions , Cátions
3.
Chem Commun (Camb) ; 58(28): 4524-4527, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35302568

RESUMO

In this study, we found that a recently discovered ECD-Raman effect dominated over the natural Raman optical activity in a series of atropisomeric naphthalenediimides, and we investigated the kind of information about the molecular structure that could be obtained from the spectra. The ECD-Raman effect is polarised Raman scattering modulated by electronic circular dichroism. We showed that the spectra significantly depended on the substitution of the solute and/or the change of the solvent. Moreover, the spectra could be well-predicted by the theory, thus providing an interesting tool to monitor the chirality of the binaphthyl compounds.


Assuntos
Análise Espectral Raman , Dicroísmo Circular , Estrutura Molecular , Soluções , Solventes/química
4.
Biosens Bioelectron ; 167: 112446, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32818748

RESUMO

Fast, simple in use and highly effective voltammetric enantiosensor dedicated for determination of thalidomide (TD) enantiomers (especially towards the toxic (S)-enantiomer) in blood plasma is still desirable. Here we have proven that newly synthesized chiral naphthalene diimide (NDI) derivatives are excellent electroactive materials for TD enantiosensors. The recognition process relies on the specific interaction between the chiral NDI receptor and the thalidomide enantiomer of the opposite configuration. This unique specific interaction between (S)-thalidomide and (R)-NDI derivative counterparts, evident in the DPV voltammograms, was confirmed by molecular modeling. The demonstrated voltammetric enantiosensors are characterized by the low detection limit at the level of µg·L-1, wide analytical range from 5·10-4 - 10 mg·L-1, high selectivity and long lifetime. The results of the recovery rates showed a very good degree of accuracy towards the determination of (S)-thalidomide in the blood samples, so it can be successfully used in the analysis of clinical samples.


Assuntos
Técnicas Biossensoriais , Talidomida , Imidas , Naftalenos , Plasma , Estereoisomerismo
5.
Chem Sci ; 12(3): 911-916, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34163857

RESUMO

Raman optical activity (ROA) spectra recorded for a chiral naphthalene diimide derivative (nBu-NDI-BINAM) dissolved in a series of solvents exhibit strong solute to solvent induced chirality with: (1) dominating bands of solvents, (2) nBu-NDI-BINAM resonance ROA (RROA) bands which are barely visible, (3) monosignate RROA Solvent spectra with an unexpected sign concordant with that of the ECD band of the resonant electronic state, (4) bisignate RROA bands for a few solvents, and (5) superposition of non-resonant and resonant ROA bands of the chiral solvents. The unusual ROA enhancement was explained in terms of resonance energy transfer with resonant Raman emission. The surprising RROA sign-switching was found to be due to specific conformational equilibria where one solute conformer dominates in the ground and the other in the first excited singlet state, and, the signs of the related ECD bands of these two conformers are opposite.

6.
J Osteoporos ; 2019: 9214926, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885852

RESUMO

INTRODUCTION: The appropriate intake of calcium and vitamin D in women's diet is significant for a proper maintenance of the skeletal system. RESEARCH AIM: The aim of the research was to assess the calcium and vitamin D supply in a diet among women regularly practicing sport. METHODOLOGY: The research was completed by 593 women at the age of 18-50 (median 25) who played sports regularly (at least 2 times a week). To assess the calcium and vitamin D intake, short Food Frequency Questionnaires for calcium and vitamin D (VIDEO-FFQ) were used. The examined group was provided with the questionnaires via social media. To assess intake levels, the authors applied the group-based cutoff point method (calcium norm was EAR 800 mg/day; vitamin D norm was AI 15 µg/day). RESULTS: The median of calcium and vitamin D intake in a diet was 502 mg/day and 5.2 µg/day, respectively (Q25 and Q75 for calcium was 387 mg/day and 627 mg/day, respectively, and for vitamin D was 3.4 µg/day and 8.2 µg/day, respectively). In relation to the EAR norm for calcium and AI norm for vitamin D, 92.0% of the examined participants in a group demonstrated lower than recommended calcium intake levels and 97.3% showed lower than recommended vitamin D intake levels. Calcium and vitamin D supplementation was used by 13.1% (in this subgroup, 11.5% of the examined group members did not need it) and 56.8% of the examined women (in this subgroup, 2.4% of the examined group did not need it), respectively. After including the calcium and vitamin D intake, the supply median for the whole group was 535 mg/day and 28.8 µg/day, respectively (Q25 and Q75 for calcium was 402 mg/day and 671 mg/day, and for vitamin D was 6.3 µg/day and 55.7 µg/day, respectively); 87.5% of the examined participants did not meet the EAR norms for calcium and 42.0% did not meet the AI norm for vitamin D. Among the women supplementing calcium, 58.9% did not reach the reference intake value; however, all women supplementing vitamin D fulfilled the expected nutritional need. CONCLUSIONS: It is important to educate women about the necessity to provide the body with proper calcium and vitamin D intake levels in a diet in order to avoid health problems resulting from the deficit of the nutrients.

7.
Medicina (Kaunas) ; 55(10)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547119

RESUMO

Background and Objectives: This study aimed to translate the Hip disability and Osteoarthritis Outcome Score (HOOS) into the Polish language, to determine its validity and reliability, and to assess its main psychometric properties. Materials and Methods: A total of 332 hip osteoarthritis (OA) subjects were recruited to the study group and 90 healthy subjects to the control group. The study consisted of the HOOS translation and the assessment of the discriminative power, internal consistency, and the potential floor and ceiling effects followed by the determination of the construct validity and test-retest reliability. The analysis was performed using Western Ontario and McMaster Universities osteoarthritis index (WOMAC) and SF-36 questionnaires. Results: The translation process consisted of forward translation, reconciliation, backward translation, review, harmonization, and proofreading. The hip OA patients reported a reduced HOOS score when compared to the control subjects. The discriminant validity of the questionnaire was confirmed. A Cronbach's alpha of 0.97 was found, indicating a high internal consistency. The HOOS showed a significant correlation with the SF-36 and WOMAC, which ranged from r = -0.93, p-value < 0.05 for WOMAC total score to r = 0.92, and p-value < 0.05 for WOMAC daily living. No floor or ceiling effects were found. A very high intraclass correlation coefficient (ICC) was found (0.93-0.97) for the total score and the individual domains of the HOOS. Conclusions: The Polish HOOS is valid and reliable for evaluating the outcomes of hip OA patients in Poland. This questionnaire may be used with confidence for clinical and research purposes.


Assuntos
Osteoartrite do Quadril , Psicometria , Inquéritos e Questionários , Traduções , Adulto , Características Culturais , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Medição da Dor , Polônia , Qualidade de Vida , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
8.
J Antibiot (Tokyo) ; 71(8): 757-761, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29700424

RESUMO

A new metabolite, cyclic dipeptide, cis-(3S,8aS)-3-(3,4-dihydroxybenzyl)hexahydropyrrolo[1,2-a]pyrazine-1,4-dione, named JS-3 was isolated from Streptomyces sp. 8812 fermentation broth. Its chemical structure was established by means of spectroscopic analysis. A wide-range-screening study, which included inhibition assay of DD-carboxypeptidase/transpeptidase activity, determination of antibacterial, antifungal, and antiproliferative activities as well as free-radical scavenging was performed. To authors knowledge, this is the first isolation of such compound from natural sources and the first one from bacteria, Streptomyces.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Carboxipeptidases/antagonistas & inibidores , Dicetopiperazinas/farmacologia , Dipeptídeos/farmacologia , Peptidil Transferases/antagonistas & inibidores , Streptomyces/metabolismo , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Bactérias/efeitos dos fármacos , Dicetopiperazinas/isolamento & purificação , Dicetopiperazinas/metabolismo , Dipeptídeos/isolamento & purificação , Dipeptídeos/metabolismo , Fermentação , Fungos/efeitos dos fármacos
9.
J Phys Chem A ; 121(36): 6713-6726, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-28777576

RESUMO

Two enantiomers of 2-methyl-N-(1-thien-2-ylethyl)propane-2-sulfonamide (TSA) were synthesized, and their VCD, ROA, IR, and Raman spectra were registered. The solved (S)-TSA X-ray structure shows a disorder connected to the presence of two TSA conformers differing by a slight rotation of the thiophene ring. Two molecules in the unit cell of the monoclinic P21 crystal form a net of NH···OS and C*H···OS hydrogen bonds. Out of a series of computational levels tested to interpret the spectra, the B3LYP functional combined with the def2TZVP basis set satisfactorily reproduces the experimental VCD and ROA spectra. To simulate the VCD spectra of TSA enantiomers in KBr pellets, dimers and tetramers, with two different positions of the thiophene ring, were considered. The VCD spectra measured in CDCl3 are completely different from those taken in KBr due to the conformational freedom of TSA in chloroform. Seven TSA conformers fall into two groups of opposite configurations at the pyramidal N atom forming the additional stereogenic center. However, the barriers between conformers in each group are lower than the energy of thermal motions at 300 K. Thus, all conformers, but the most stable in each group, are likely to be metastable states. The calculated IR, VCD, Raman, and ROA spectra of the conformers depend not only on the type of stereogenic N atom but also on the thiophene ring rotation. Yet, they are likely to coexist because of low barriers between them. Three approaches were tested to reproduce the chiroptical spectra in solution using PCM and hybrid solvation models. As a consequence, it was found that a model in which all conformers contribute to the spectra with equal population factors seems to best reproduce the experimental data. Such a result suggests that in a dissolved state in 300 K TSA occurs in a very shallow potential well and all of its conformers coexist.

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