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1.
Phys Chem Chem Phys ; 24(16): 9619-9625, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35403645

RESUMO

Vibrational circular dichroism (VCD) and Raman optical activity (ROA) are two spectroscopic techniques that are sensitive towards the conformational behaviour of molecules, and are often complementary herein. In this work we pursue the determination of the conformational ensemble of the antibiotic glycopeptide vancomycin in DMSO through comparison of experimental and computational spectra, both for VCD and ROA. ROA is found to be highly suitable for the task, identifying an ensemble that strongly resembles the NMR conformation. In the case of VCD, however, a too high sensitivity of the intensities with respect to minor conformational changes hampers a reliable conformational analysis. Whence attempting to improve the match between the VCD experiment and calculations by any means - e.g., by inducing minor conformational changes or including solvent effects in the calculations - we show that there is the risk of going down the rabbit hole. In conclusion, this work contributes to the broader understanding of where, when and how VCD and ROA can be deployed as techniques for conformational analysis.


Assuntos
Dimetil Sulfóxido , Vancomicina , Antibacterianos , Dicroísmo Circular , Rotação Ocular , Análise Espectral Raman/métodos
2.
J Phys Chem Lett ; 13(17): 3873-3877, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35467874

RESUMO

Chiral metal complexes exhibit rich photophysical properties and are important for applications ranging from biosensing to photocatalysis. We present a combined experimental and computational approach leading to information about energies and transition moments of excited electronic states, documented on two chiral metal complexes. The experimental protocol for measurement of the resonance Raman optical activity comprises multiple techniques, i.e., absorption, circular dichroism, and polarized and differential Raman scattering. An accurate formula for subtraction of the interfering circular dichroism/polarized Raman scattering effect is given. An analysis of the spectra based on density functional theory calculations unveils the geometric and electronic structures of the molecules. Such insight into molecular electronic states of chromophores may be useful for understanding and tuning photochemical properties of metal-containing complexes, biomolecules, and supramolecules.


Assuntos
Complexos de Coordenação , Análise Espectral Raman , Dicroísmo Circular , Complexos de Coordenação/química , Eletrônica , Rotação Ocular , Análise Espectral Raman/métodos
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 276: 121176, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35439653

RESUMO

The great interest in terpene compounds such as 2-, 3- and 4-carene is due to their undeniable biological activity. However, in recent years, there has been increasing interest in carenes in the context of biofuels. The current growing and insatiable demand for petroleum fuels creates an area for alternative biofuels. Research shows that natural products, which contain compounds from the carenes family, such as pine oil or turpentine (3-carene can constitute up to 70% of the composition of turpentine), can be successfully used as biofuels or additives in biofuels. In this work, both experimental and calculated (DFT/B3LYP/aug-cc-pVDZ) Raman and ROA (Raman optical activity) spectra of 1S,3R-cis-4-carene and 1S,3S-trans-4-carene were reported and analyzed for the first time. Then these spectra were compared with Raman and ROA spectra of other chiral members of the carenes family (1S-2-carene and 1S-3-carene). This knowledge about the spectra of individual carenes made it possible to identify (+)-1S-3-carene in selected samples of pine essential oil from the needles of Pinius sylvestris (Scots pine).


Assuntos
Óleos Voláteis , Análise Espectral Raman , Biocombustíveis , Rotação Ocular , Análise Espectral Raman/métodos , Terpenos , Terebintina
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 276: 121180, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35397447

RESUMO

The rationale of this paper is to shed some light on the origin of the optical response of two similar chiral fluorene copolymers in correlation with their vibrational modes, to understand how a chiral center placed in a ramification affects the optical properties of the main chain. Various spectroscopic ellipsometric techniques, in the scope of the Stokes theory were used to characterize the optical-vibrational behavior of the polyfluorenes: ellipsometry in emission (EE), transmission (TE), and Raman (ERS). The results showed that the optical activity and the emission of the circularly polarized light depends substantially on the interaction of the chiral carbon in the ramification and the main chain through specific optically active vibrational modes, for each sample. One interesting achievement was to find the absolute dextrorotatory configuration of the studied molecules, that could induce a helicoidal structure to the entire material.


Assuntos
Análise Espectral Raman , Vibração , Dicroísmo Circular , Eletrônica , Rotação Ocular , Análise Espectral Raman/métodos
5.
Nano Lett ; 22(7): 2835-2842, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35369696

RESUMO

Measurements of optical activity can be readily performed in transparent matter by means of a rotation of transmitted light polarization. In the case of opaque bulk materials, such measurements cannot be performed, making it difficult to assess possible chiral properties. In this work, we present full angular polarization dependencies of the Raman modes of bulk 1T-TaS2, which has recently been suggested to have chiral properties after pulsed laser excitation. We found that a mechanical rotation of the sample does not alter polarization-resolved Raman spectra, which can only be explained by introducing an antisymmetric Raman tensor, frequently used to describe Raman optical activity (ROA). Raman spectra obtained under circularly polarized excitation demonstrate that 1T-TaS2 indeed shows ROA, providing strong evidence that 1T-TaS2 is chiral under the used conditions of laser excitation. Our results suggest that ROA may be used as a universal tool to study chiral properties of quantum materials.


Assuntos
Análise Espectral Raman , Rotação Ocular , Análise Espectral Raman/métodos
6.
Small ; 18(17): e2200620, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35319827

RESUMO

Liquid metals (such as gallium or Ga) exist in liquid states under ambient conditions and are hardly sculpted in chiral structures. Herein, through electron-beam evaporation of Ga, hemispherical achiral Ga nanoparticles (NPs) are randomly immobilized along helical surfaces of SiO2 nanohelices (NHs), functioning as a chiral template. Helical assembly of Ga NPs shows chiroplasmonic optical activity owing to collective plasmon-plasmon interactions, which can be tuned as a function of a helical SiO2 pitch (P) and the amount of Ga evaporated. At a P of ≈150 nm, the chiroplasmonic optical activity, evaluated with anisotropic g-factor, can be as large as ≈0.1. Because the SiO2 NHs and Ga NPs have high environmental stability of nanostructures, the chiroplasmonic optical activity shows excellent anti-aging stability, despite slight blue shift and chiroplasmonic degradation for the first 2 weeks. Spontaneous oxidation of the Ga NPs enables the formation of dense Ga2 O3 layers covering Ga cores to prevent further oxidation and thus to stabilize the chiroplasmonic optical activity. This work devises an alternative approach to impose optical activity onto Ga NPs, providing an additional degree of freedom (i.e., chirality) for Ga-based flexible electronic devices to develop advanced applications of 3D display, circular polarizers, bio-imaging, and bio-detection.


Assuntos
Gálio , Nanopartículas Metálicas , Nanoestruturas , Nanopartículas Metálicas/química , Nanoestruturas/química , Rotação Ocular , Dióxido de Silício
7.
J Am Chem Soc ; 144(11): 4845-4852, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35167256

RESUMO

Accomplishing optical activity in achiral materials has long been a challenge. Achiral nanomaterials that crystallize in achiral point groups are generally optically inactive. Herein we report the surprising observation of optical activity in several achiral point groups for supercrystals assembled from anisotropic metal nanoclusters with atomic precision. By analyzing multiple achiral nanoclusters with different molecular structures and symmetry space groups, we have identified that the molecular anisotropy of nanocluster entities and their asymmetric arrangement in point groups of supercrystals are the two key factors for the realization of optical activity in such supercrystals. We have further exploited the polarization effect of the nanocluster supercrystals as a polarization switch that can alter the polarized state of the linearly polarized light. Our findings have broadened the fundamental principles for producing nanomaterial-based optical activity and devices with polarization effects.


Assuntos
Nanoestruturas , Anisotropia , Cristalografia , Estrutura Molecular , Rotação Ocular
8.
Nano Lett ; 22(5): 1880-1888, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35179380

RESUMO

There is substantial interest regarding the understanding and designing of nanoengineered bacteria to combat various fatal diseases. Here, we report the nanoengineering of Bifidobacterium bifidum using Cremophor EL to encapsulate organic dye molecules by simple incubation and washing processes while maintaining the bacterial morphology and viability. The prepared functional bacteria exhibit characteristics such as optical absorbance, unique fluorescence, powerful photothermal conversion, low toxicity, excellent tumor targeting, and anticancer efficacy. They also displayed significant in vivo fluorescent expression in implanted colorectal cancerous tumors. Moreover, the powerful photothermal conversion of the functional bacteria could be spatiotemporally evoked by biologically penetrable near-infrared laser for effective tumor regression in mice, with the help of immunological responses. Our study demonstrates that a nanoengineering approach can provide the strong physicochemical traits and attenuation of living bacterial cells for cancer immunotheranostics.


Assuntos
Bifidobacterium bifidum , Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Fluorescência , Camundongos , Nanopartículas/química , Rotação Ocular , Fototerapia
9.
Fitoterapia ; 157: 105139, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35108573

RESUMO

A phytochemical investigation was conducted on Euphorbia helioscopia, resulting in the isolation of thirteen compounds, including nine undescribed diterpenoids, Euphzycopias A - I (1-9), of which the skeletons of compounds 1-4 were found in E. helioscopia L. Compounds 1-3 had 5/7/6 cyclic systems, while compound 4 had a 4/11 polycyclic system with a 4,7-cyclic ether between C-4 and C-7. The anti-inflammasome test using the isolated compounds (1-6, 8-13) showed that the diterpenes from E. helioscopia L. had a strong inhibitory effect on NLRP3 inflammasomes with IC50 values of 3.34-14.92 µM.


Assuntos
Diterpenos/farmacologia , Euphorbia/química , Inflamassomos/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Humanos , Inflamassomos/química , Inflamassomos/isolamento & purificação , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Rotação Ocular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Espectrofotometria Infravermelho
10.
Phys Chem Chem Phys ; 24(5): 3191-3199, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35043805

RESUMO

Experimental and theoretical Raman optical activity (ROA) study of α-helical peptides and proteins has suggested that the relative intensity of two extended amide III ROA bands at ∼1340 cm-1 (I band) and ∼1300 cm-1 (II band) can be used to monitor the permittivity of the surrounding medium of the α-helix. So far, the ROA intensity ratio, II/III, has been interpreted from two different viewpoints. The first one is in terms of a direct effect of permittivity around the α-helix. The second one is based on a structural equilibrium of two types of α-helical structures, "hydrated" and "unhydrated" ones. In the present study, temperature- and solvent-dependences of II/III are measured for highly-α-helical peptides and compared to the theoretical spectra while varying the permittivity or the type of α-helical structure. A fragment method with partial optimization in the normal modes is adopted in density functional theory calculations. The main features of the experimental spectra and a trend of the observed II/III are well reproduced by the simulations, which leads us to a conclusion that the II/III is dominantly governed by a direct influence of the permittivity of the environment and just accessorily by the equilibrium of the two types of α-helices. The simulations also opposed the conventional assignments of the I and II bands to "hydrated" and "unhydrated" α-helical structures, respectively. In the case of α-helical proteins, solvent exposure of the α-helix may be monitored by the ROA ratio.


Assuntos
Amidas , Análise Espectral Raman , Rotação Ocular , Peptídeos , Conformação Proteica em alfa-Hélice
11.
Nano Lett ; 22(2): 846-852, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35023753

RESUMO

Structural engineering permits the introduction of chirality into organic-inorganic hybrid metal halides (HMHs), which creates a promising and exclusive material for applications in various optoelectronics. However, the optical activity regulation of chiral HMHs remains largely unexplored. In this work, we have synthesized two pairs of lead-free chiral HMHs with a zero-dimensional tetrahedral arrangement, i.e., (R- and S-1-(1-naphthyl)ethylammonium)2CuCl4 and (R- and S-1-(2-naphthyl)ethylammonium)2CuCl4. The magnitude of optical activity in these HMHs can be efficiently modulated as a result of the different magnetic transition dipole moments. Furthermore, these HMHs exhibited effective second-harmonic generation (SHG) and distinct SHG-circular dichroism (CD), with (R-1-(1-naphthyl)ethylammonium)2CuCl4 having an anisotropy factor (gSHG-CD) of up to 0.41. This work not only provides insights into regulating the optical activity and anisotropic SHG effect of lead-free chiral HMHs but also confirms the feasibility of SHG-CD spectroscopy as a promising tool for characterizing the intrinsic optical activity of chiral materials.


Assuntos
Microscopia de Geração do Segundo Harmônico , Anisotropia , Dicroísmo Circular , Cobre , Rotação Ocular , Microscopia de Geração do Segundo Harmônico/métodos
12.
PLoS Comput Biol ; 18(1): e1009678, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35051172

RESUMO

Sugars are crucial components in biosystems and industrial applications. In aqueous environments, the natural state of short saccharides or charged glycosaminoglycans is floating and wiggling in solution. Therefore, tools to characterize their structure in a native aqueous environment are crucial but not always available. Here, we show that a combination of Raman/ROA and, on occasions, NMR experiments with Molecular Dynamics (MD) and Quantum Mechanics (QM) is a viable method to gain insights into structural features of sugars in solutions. Combining these methods provides information about accessible ring puckering conformers and their proportions. It also provides information about the conformation of the linkage between the sugar monomers, i.e., glycosidic bonds, allowing for identifying significantly accessible conformers and their relative abundance. For mixtures of sugar moieties, this method enables the deconvolution of the Raman/ROA spectra to find the actual amounts of its molecular constituents, serving as an effective analytical technique. For example, it allows calculating anomeric ratios for reducing sugars and analyzing more complex sugar mixtures to elucidate their real content. Altogether, we show that combining Raman/ROA spectroscopies with simulations is a versatile method applicable to saccharides. It allows for accessing many features with precision comparable to other methods routinely used for this task, making it a viable alternative. Furthermore, we prove that the proposed technique can scale up by studying the complicated raffinose trisaccharide, and therefore, we expect its wide adoption to characterize sugar structural features in solution.


Assuntos
Análise Espectral Raman/métodos , Açúcares/análise , Açúcares/química , Água/química , Biologia Computacional , Simulação de Dinâmica Molecular , Rotação Ocular
13.
Fitoterapia ; 157: 105120, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34974139

RESUMO

Three new limonoids, walsurauias A-C (1-3), along with four known ones, were isolated from the leaves and twigs of Walsura yunnanensis C. Y. Wu. Their structures were determined on the basis of comprehensive spectroscopic data analysis. The new limonoids were screened for their cytotoxic activity (IC50 0.81-5.73 µM) against four human cancer cell lines, including A549, HepG2, HCT116 p21KO and CNE-2. And α,ß-unsaturated ketone moieties in rings A and B are essential for their cytotoxic activity. Selected compounds were further investigated. Compounds 1-3 effectively induced G2/M cell cycle arrest and apoptosis in a dose-dependent manner in cancer cells. In addition, compounds 1-3 inhibited the colony formation and compounds 2 and 3 suppressed the migration of cancer cells.


Assuntos
Limoninas/toxicidade , Meliaceae/química , Apoptose , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Citometria de Fluxo , Humanos , Concentração Inibidora 50 , Limoninas/química , Limoninas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Rotação Ocular , Folhas de Planta/química , Caules de Planta/química , Espectrofotometria Infravermelho , Cicatrização/efeitos dos fármacos
14.
Fitoterapia ; 157: 105118, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34974140

RESUMO

Melodicochinines A - D (1-4), four new monoterpene indole alkaloids (MIAs), along with 21 known ones, were isolated from the stems and twigs of Melodinus cochinchinensis. Their structures were elucidated on the basis of extensive spectroscopic analysis. A ubiquitin-rhodamine 110 assay showed that 11-methyloxytabersonine had potential inhibitory effect against ubiquitin-specific protease 7 (USP7).


Assuntos
Apocynaceae/química , Extratos Vegetais/química , Alcaloides de Triptamina e Secologanina/isolamento & purificação , China , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Rotação Ocular , Extratos Vegetais/isolamento & purificação , Caules de Planta/química , Alcaloides de Triptamina e Secologanina/química , Espectrofotometria Infravermelho
15.
Fitoterapia ; 156: 105091, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826555

RESUMO

Ten undescribed cadinane-type sesquiterpenes (1-10) were isolated from the whole plant of Eupatorium chinense. Their planar structures were mainly elucidated by extensive analysis of spectroscopic data and DFT NMR calculations. The absolute configurations of 1, 2, and 3 were determined by TDDFT ECD calculations while those of compounds 4-7 and 9 were confirmed by single crystal X-ray diffraction experiments. Compounds 2 and 3 are a pair of C-10 epimers, compounds 4 and 5 a pair of C-1 epimers, and compounds 9 and 10 a pair of compounds isomerized at both C-1 and C-10. A possible biosynthetic pathway for these new sesquiterpenes was proposed.


Assuntos
Asteraceae/química , Extratos Vegetais/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rotação Ocular , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Sesquiterpenos/química , Sesquiterpenos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
16.
Fitoterapia ; 156: 105096, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34883224

RESUMO

Two unprecedented ent-18,19-dinoricetexane diterpenoid glycosides, named abieshanesides A (1) and B (2), together with seven known compounds, have been isolated from the dead trunks and branches of Abies beshanzuensis M.H. Wu. To our knowledge, abieshanesides A and B represent the first ent-18,19-dinoricetexane diterpenoid glycosides found in natural sources. Their structures and absolute configurations were elucidated by using a combination of spectroscopic techniques and comparison of experimental and calculated electronic circular dichroism (ECD) data. The MTT experiments showed that (E)-resveratrol (7) could inhibit viability of MH7A cells with the IC50 value of 12.5 µM. Compound 7 was able to block MH7A cell proliferation and was associated with G0/G1-phase cell cycle arrest. Flow cytometric analysis showed that the treatment by 7 significantly induced the proliferation of MH7A cells in a dose-dependent manner.


Assuntos
Abies/química , Diterpenos/química , Glicosídeos/química , Linhagem Celular , Sobrevivência Celular , China , Diterpenos/isolamento & purificação , Glicosídeos/isolamento & purificação , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Rotação Ocular , Caules de Planta/química
17.
J Phys Chem B ; 126(2): 355-367, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-34792364

RESUMO

Resonance Raman Optical Activity (RROA) appeared as a natural extension of the nonresonance branch. It combines the structural sensitivity of chiroptical spectroscopy with the signal enhancement coming from the resonance of molecular electronic transitions with the excitation laser light. However, the idea has been hampered by many technical and theoretical problems that are being clarified only in recent years. We provide the theoretical basis and several examples documenting the problems, achievements, and potential of RROA, in particular in biomolecular studies.


Assuntos
Gases , Análise Espectral Raman , Luz , Rotação Ocular , Análise Espectral Raman/métodos , Vibração
18.
Fitoterapia ; 156: 105086, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34798164

RESUMO

Two new isoquinoline alkaloids, cryptowrayines A (1) and B (2), along with one known pavine alkaloid (-)-12-hydroxyeschscholtzidine (3), were isolated from the twigs of Cryptocarya wrayi. The structures of new compounds were elucidated by extensive spectroscopic data analysis and electronic circular dichroism (ECD) calculations. Both compounds 1 and 2 exhibited moderate quinone reductase inducing activity in Hepa 1c1c7 cells.


Assuntos
Alcaloides/isolamento & purificação , Cryptocarya/química , Isoquinolinas/isolamento & purificação , Alcaloides/química , Alcaloides/metabolismo , Glucosidases/antagonistas & inibidores , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/metabolismo , Concentração Inibidora 50 , Isoquinolinas/química , Isoquinolinas/metabolismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/análise , Rotação Ocular
19.
Fitoterapia ; 156: 105095, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34896204

RESUMO

Marine-derived fungi can usually produce structurally novel and biologically potent metabolites. In this study, a new diketopiperazine alkaloid (1) and two new polyketides (10 and 11), along with 8 known diketopiperazine alkaloids (2-9) were isolated from marine-derived fungus Penicillium sp. TW58-16. Their structures were fully elucidated by analyzing UV, IR, HR-ESI-MS, 1D, and 2D NMR spectroscopic data. The absolute configurations of the new compounds 1, 10 and 11 were ascertained by X-ray diffraction (Cu Kα radiation) and comparing their CD data with those reported. In addition, the antibacterial activities of these compounds against Helicobacter pylori in vitro were assessed. Results showed that compounds 3, 6, 8 and 9 displayed moderate antibacterial activity against standard strains and drug-resistant clinical isolates of H. pylori in vitro. This result demonstrates that diketopiperazine alkaloids could be lead compounds to be explored for the treatment of H. pylori infection.


Assuntos
Alcaloides/farmacologia , Antibacterianos/farmacologia , Dicetopiperazinas/farmacologia , Helicobacter pylori/efeitos dos fármacos , Penicillium/química , Policetídeos/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Cromatografia em Gel , Cromatografia Líquida , Cristalografia por Raios X , Dicetopiperazinas/química , Dicetopiperazinas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Rotação Ocular , Policetídeos/química , Policetídeos/isolamento & purificação , Água do Mar , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Taiwan
20.
Fitoterapia ; 156: 105101, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34921925

RESUMO

Chemical fractionation of the EtOH extract of a medicinal macro fungus, Inonotus obliquus, afforded an array of lanostane-type triterpenoids (1-11) including two new ones (1 and 8). The structures of these compounds were determined on the basis of spectroscopic analyses, single crystal X-ray crystallography of 3-6 and biosynthetic considerations. With the confirmatory structural information provided by X-ray diffraction analysis in hand, several previously reported 21,24-cyclolanostanes, such as inonotsutriols A-C and (20R,21S,24S)-21,24-cyclopenta-3ß,21,25-trihydroxylanosta-8-ene, were structurally corrected. In addition, the NMR data of other types of 21,24-cyclo triterpenoids were also re-examined and structural revisions were thus suggested. Compounds 2, 6 and 8 showed significant cytostatic effects against a panel of tumor cell lines with IC50 values ranging from 7.80 to 18.5 µM. Further assays established that compound 2 exerted promising in vitro anti-breast cancer potential by inhibiting the proliferation and migration of 4T1 cells.


Assuntos
Inonotus/química , Triterpenos/isolamento & purificação , Bioensaio , Linhagem Celular , Sobrevivência Celular , Cristalografia por Raios X , Carpóforos/química , Concentração Inibidora 50 , Estrutura Molecular , Rotação Ocular , Triterpenos/química , Triterpenos/metabolismo , Triterpenos/toxicidade , Difração de Raios X
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