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1.
RSC Adv ; 14(19): 13129-13141, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38655481

RESUMO

New amide conjugates 1-6 of hydroxycinnamic acids (HCA) and 5'-deoxy-5-fluorocytidine (5-dFCR), the prodrug of 5-fluorouracil (5-FU), were synthesized and tested in vitro against pancreatic cancer lines (PDAC). The compounds showed slightly higher efficacy against primary BxPC-3 cells (IC50 values of 14-45 µM) than against metastatic AsPC-1 (IC50 values of 37-133 µM), and similar to that of 5-FU for both PDAC lines. Compound 1, which has a para-(acetyloxy)coumaroyl substituent, was found to be the most potent (IC50 = 14 µM) with a selectivity index of approximately 7 to normal dermal fibroblasts (IC50 = 96 µM). The potential pharmacological profiles were discussed on the basis of the ADME data. Docking to the carboxylesterase CES2 showed that the synthesized compounds have the ability to bind via hydrogen bonding between a specific acetate group of the sugar moiety and Ser228, which belongs to the catalytic triad that causes hydrolysis. Docking to albumin, a major transport protein in the circulatory system, revealed a strong interaction of the conjugates at the binding site which is native to warfarin and responsible for its transport in the body.

2.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473820

RESUMO

New amide conjugates of hydroxycinnamic acids (HCAs) and the known antineoplastic 5,11-dimethyl-5H-indolo[2,3-b]quinoline (DiMIQ), an analog of the natural alkaloid neocryptolepine, were synthesized and tested in vitro for anticancer activity. The compound 9-[((2-hydroxy)cinnamoyl)amino]-5,11-dimethyl-5H-indolo[2,3-b]quinoline (2), which contains the ortho-coumaric acid fragment, demonstrated dose-dependent effectiveness against both normal BxPC-3 and metastatic AsPC-1 pancreatic cancer cells. The IC50 values for AsPC-1 and BxPC-3 were 336.5 nM and 347.5 nM, respectively, with a selectivity index of approximately 5 for both pancreatic cancer cells compared to normal dermal fibroblasts. Conjugate 2 did not exhibit any hemolytic activity against human erythrocytes at the tested concentration. Computational studies were performed to predict the pharmacokinetic profile and potential mechanism of action of the synthesized conjugates. These studies focused on the ADME properties of the conjugates and their interactions with DNA, as well as DNA-topoisomerase alpha and beta complexes. All of the conjugates studied showed approximately one order of magnitude stronger binding to DNA compared to the reference DiMIQ, and approximately two orders of magnitude stronger binding to the topoisomerase II-DNA complex compared to DiMIQ. Conjugate 2 was predicted to have the strongest binding to the enzyme-DNA complex, with a Ki value of 2.8 nM.


Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Quinolinas , Humanos , Simulação de Acoplamento Molecular , Hormônios Pancreáticos , Ácidos Cumáricos , Complexos Multienzimáticos , DNA , Relação Estrutura-Atividade , Estrutura Molecular , Linhagem Celular Tumoral
3.
J Parasitol Res ; 2023: 6675081, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046256

RESUMO

New protocol for the preparation of the novel caffeic acid derivatives using the Wittig reaction has been applied to follow the principles of green chemistry. The compounds have been evaluated against chloroquine-sensitive and chloroquine-resistant P. falciparum strains. Their cytotoxicity to normal human dermal fibroblasts and their propensity to induce hemolysis have been also determined. Ethyl (2E)-3-(2,3,4-trihydroxyphenyl)-2-methylpropenoate has exhibited the highest antiplasmodial activity against P. falciparum strains without the cytotoxic and hemolytic effects. This derivative is significantly more potent than caffeic acid parent structure. The application of our one-step procedure has been shown to be rapid and efficient. It allows for an easy increase of input data to refine the structure-activity relationship model of caffeates as the antimalarials. The one-step approach meets the conditions of "atom economy" and eliminates hazardous materials. Water has been used as the effective medium for the Wittig reaction to avoid toxic organic solvents.

4.
J Clin Med ; 12(14)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37510819

RESUMO

Autoresuscitation is a phenomenon of the heart during which it can resume its spontaneous activity and generate circulation. It was described for the first time by K. Linko in 1982 as a recovery after discontinued cardiopulmonary resuscitation (CPR). J.G. Bray named the recovery from death the Lazarus phenomenon in 1993. It is based on a biblical story of Jesus' resurrection of Lazarus four days after confirmation of his death. Up to the end of 2022, 76 cases (coming from 27 countries) of spontaneous recovery after death were reported; among them, 10 occurred in children. The youngest patient was 9 months old, and the oldest was 97 years old. The longest resuscitation lasted 90 min, but the shortest was 6 min. Cardiac arrest occurred in and out of the hospital. The majority of the patients suffered from many diseases. In most cases of the Lazarus phenomenon, the observed rhythms at cardiac arrest were non-shockable (Asystole, PEA). Survival time after death ranged from minutes to hours, days, and even months. Six patients with the Lazarus phenomenon reached full recovery without neurological impairment. Some of the causes leading to autoresuscitation presented here are hyperventilation and alkalosis, auto-PEEP, delayed drug action, hypothermia, intoxication, metabolic disorders (hyperkalemia), and unobserved minimal vital signs. To avoid Lazarus Syndrome, it is recommended that the patient be monitored for 10 min after discontinuing CPR. Knowledge about this phenomenon should be disseminated in the medical community in order to improve the reporting of such cases. The probability of autoresuscitation among older people is possible.

5.
Carbohydr Res ; 531: 108861, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37356236

RESUMO

2-Deoxy-d-glucose (2-DG), a compound known to interfere with d-glucose and d-mannose metabolism, has been tested as a potential anticancer and antiviral agent. Preclinical and clinical studies focused on 2-DG have highlighted several limitations related to 2-DG drug-like properties, such as poor pharmacokinetic properties. To overcome this problem, we proposed design and synthesis of novel 2-DG prodrugs that subsequently could be tested using a variety of biochemical and molecular methods. We narrowed here our focus to esters of 2-DG as potential prodrugs based on the hypothesis that ubiquitous esterases will regenerate 2-DG, leading to increased circulation time of drug and adequate organ and tumor penetration. Testing this hypothesis in vitro and, especially, in vivo requires significant amounts of respective pure mono- and previously unknown di-acetylated water-soluble derivatives of 2-DG. Development of their efficient and practical method of synthesis was imperative. We describe novel facile and scalable syntheses of seven selectively acetylated water-soluble derivatives of 2-DG and present a detailed 1H and 13C NMR analysis of all final products. X-ray diffraction analysis has been performed for compound WP1122 that was selected for detailed preclinical and subsequent clinical evaluation as potential anticancer or antiviral agent.


Assuntos
Glucose , Pró-Fármacos , Glucose/química , Antimetabólitos , Manose/química , Desoxiglucose/química , Antivirais/farmacologia
6.
Int J Mol Sci ; 24(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240221

RESUMO

A series of new ursolic acid (UA) derivatives substituted with various amino acids (AAs) or dipeptides (DP) at the C-3 position of the steroid skeleton was designed and synthesized. The compounds were obtained by the esterification of UA with the corresponding AAs. The cytotoxic activity of the synthesized conjugates was determined using the hormone-dependent breast cancer cell line MCF-7 and the triple-negative breast cancer cell line MDA. Three derivatives (l-seryloxy-, l-prolyloxy- and l-alanyl-l-isoleucyloxy-) showed micromolar IC50 values and reduced the concentrations of matrix metalloproteinases 2 and 9. Further studies revealed that for two compounds (l-seryloxy- and l-alanyl-l-isoleucyloxy-), a possible mechanism of their antiproliferative action is the activation of caspase-7 and the proapoptotic Bax protein in the apoptotic pathway. The third compound (l-prolyloxy- derivative) showed a different mechanism of action as it induced autophagy as measured by an increase in the concentrations of three autophagy markers: LC3A, LC3B, and beclin-1. This derivative also showed statistically significant inhibition of the proinflammatory cytokines TNF-α and IL-6. Finally, for all synthesized compounds, we computationally predicted their ADME properties as well as performed molecular docking to the estrogen receptor to assess their potential for further development as anticancer agents.


Assuntos
Antineoplásicos , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/química , Estrutura Molecular , Ácido Ursólico
7.
Artigo em Inglês | MEDLINE | ID: mdl-36231428

RESUMO

Background: In patients after experiencing stroke, the cognitive-behavioral deficits and disorders of verbal communication limit the effectiveness of rehabilitation. The key is to diagnose them at an early stage of rehabilitation and to implement appropriate psychological and speech therapy. Objective: Identify differences in the frequency and effectiveness of cognitive-behavioral disorder therapy depending on the clinical type of stroke, assessed before and after rehabilitation treatment, and their presentation using the ICF (International Classification of Functioning, Disability, and Health) classification. Materials and Methods: The study was prospective and included the analysis of cognitive-behavioral and verbal communication disorders. The study consisted of 47 patients after intracerebral hemorrhage (ICH) and 47 patients after an ischemic stroke (IS) before the implementation of rehabilitation and after completing a 4-week rehabilitation. Results: In the group after ICH, psychological therapy significantly reduced the disturbances of consciousness and orientation (p < 0.001) and improved the speed of performing tasks in tests (p < 0.001). In patients after IS and ICH, memory and attention function improved significantly (p < 0.001). Moreover, in patients after ICH, language function deficits decreased significantly (p = 0.018). Mood disturbances were maintained in 17% of patients after ICH and 40% of patients after IS (p = 0.007). Speech therapy reduced speech articulation disorders and aphasia in 85% of patients after ICH (p = 0.001) and in 68% of patients after IS (p = 0.033). Conclusions: The frequency and type of cognitive-behavioral and verbal communication disorders vary depending on the history of ICH or IS. The ICF classification may be useful in assessing and analyzing cognitive-behavioral and verbal communication disorders, which may lead to the implementation of appropriate psychological and speech therapy at an early stage of rehabilitation and increase the effectiveness of the therapy.


Assuntos
Transtornos da Comunicação , Acidente Vascular Cerebral Hemorrágico , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Hemorragia Cerebral , Cognição , Comunicação , Humanos , Estudos Prospectivos
8.
Steroids ; 188: 109115, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36154831

RESUMO

A series of novel diosgenin (DSG) derivatives has been synthesized and tested in vitro for their antioxidant activity. Initially, four analogues have been evaluated for their cytotoxicity using normal human skin fibroblast (NHDF) as model cells. As a result, 84% of NHDF cells were still alive at 5 µM, so these compounds can be considered as innoxious to fibroblasts at this concentration. Then, hemolytic activity against human erythrocytes was studied in order to evaluate the potential impact of tested compounds against normal host cells. The result < 5% of hemolysis rates suggest no lytic activity for most compounds. After that, the main test - evaluation the antioxidant effect of DSG and its new derivatives against lipid peroxidation in the o/w emulsion model - was performed. The most promising compound (8) exhibited the significant antioxidant activity and the biocompatibility towards normal human dermal fibroblasts and red bloods cells. This p-aminobenzoic derivative revealed 61.6% blocking of induced lipid oxidation. Furthermore, eleven predicted ADME properties were predicted for all tested compounds and revealed that they are in compliance with drug-likeness criteria.


Assuntos
Diosgenina , Humanos , Diosgenina/farmacologia , Antioxidantes/farmacologia , Hemólise , Morte Celular
9.
Biomedicines ; 9(11)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34829746

RESUMO

Plant phenolic compounds have shown the ability to cooperate with one another at low doses in producing enhanced anticancer effects. This may overcome the limitations (e.g., poor bioavailability and high-dose toxicity) in developing these agents as cancer medicines. We have previously reported that the hydroxycinnamic acid derivative (HCAD) methyl-4-hydroxycinnamate and the phenolic diterpene carnosic acid (CA) can synergistically induce massive calcium-dependent apoptosis in acute myeloid leukemia (AML) at non-cytotoxic concentrations of each agent. Here, we explored the chemical nature of the synergy between HCADs and either CA, in inducing cytotoxicity, or the active metabolite of vitamin D (calcitriol), in enhancing the differentiation of AML cells. This was done by determining the structure-activity relationship of a series of hydroxycinnamic acids and their derivatives (methyl hydroxycinnamates and hydroxybenzylideneacetones) in combination with CA or calcitriol. The HCAD/CA synergy required the following critical structural elements of an HCAD molecule: (a) the para-hydroxyl on the phenolic ring, (b) the carbon C7-C8 double bond, and (c) the methyl-esterified carboxyl. Thus, the only HCADs capable of synergizing with CA were found to be methyl-4-hydroxycinnamate and methyl ferulate, which also most potently enhanced calcitriol-induced cell differentiation. Notably, the C7-C8 double bond was the major requirement for this HCAD/calcitriol cooperation. Our findings may contribute to the rational design of novel synergistically acting AML drugs based on prototype combinations of HCADs with other agents studied here.

10.
J Org Chem ; 86(21): 14321-14332, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34591486

RESUMO

New acetyl derivatives of uracil, 6-methyluracil, and thymine were obtained in the course of an unconventional synthesis in methylene chloride. It was shown that products with the acetyloxymethyl fragment are formed according to a mechanism different from that for products with the acetyloxyethyl group. In particular, for uracil it was proven that the reaction with Ac2O, TEA, and CH2Cl2 leads to 1-acetyloxymethyluracil, where the N1 substituent is composed of the -CH2- fragment that originated from CH2Cl2 and the 1-acetyloxy moiety from Ac2O. The reaction of uracil with Ac2O, TEA, CH2Cl2, and DMAP leads to an acetyloxyethyl derivative in which the -CH2-CH2- fragment originates from TEA and the 1-acetyloxy moiety from Ac2O. A possible mechanism for the formation of new compounds was suggested and supported by the density functional theory/B3LYP quantum mechanical calculations. New compounds (39 in total, including seven deuterated) were fully characterized by nuclear magnetic resonance and high-resolution mass spectrometry techniques.


Assuntos
Cloreto de Metileno , Uracila , Anidridos Acéticos , Timina
11.
Materials (Basel) ; 13(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352809

RESUMO

Pancreatic cancer belongs to the most aggressive group of cancers, with very poor prognosis. Therefore, there is an important need to find more potent drugs that could deliver an improved therapeutic approach. In the current study we searched for selective and effective caffeic acid derivatives. For this purpose, we analyzed twelve compounds and evaluated their in vitro cytotoxic activity against two human pancreatic cancer cell lines, along with a control, normal fibroblast cell line, by the classic MTT assay. Six out of twelve tested caffeic acid derivatives showed a desirable effect. To improve the therapeutic efficacy of such active compounds, we developed a formulation where caffeic acid derivative (7) was encapsulated into liposomes composed of soybean phosphatidylcholine and DSPE-PEG2000. Subsequently, we analyzed the properties of this formulation in terms of basic physical parameters (such as size, zeta potential, stability at 4 °C and morphology), hemolytic and cytotoxic activity and cellular uptake. Overall, the liposomal formulation was found to be stable, non-hemolytic and had activity against pancreatic cancer cells (IC50 19.44 µM and 24.3 µM, towards AsPC1 and BxPC3 cells, respectively) with less toxicity against normal fibroblasts. This could represent a promising alternative to currently available treatment options.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32993081

RESUMO

Physical motion driving simulators serve as a valuable research and training tool. Since many simulator participants suffer from simulator sickness (SS), we aimed to gain a better understanding of participant-related variables that may influence its incidence and severity. The study involved a 2-min mobile-platform car rollover simulation conducted in a group of 100 healthy adult participants. SS was measured with the Simulator Sickness Questionnaire immediately before and after the simulation. We investigated how the symptomatology of SS varies with gender, as well as with participants' previous experiences such as extra driving training or car accidents. Although many SS symptoms occurred already before the simulation, all the symptoms except burping had a significantly greater incidence and severity after the simulation. Before the simulation, men reported disorientation symptoms more often than women, while participants with prior experiences of extra driving training or car accidents scored significantly higher in three out of four Questionnaire components: nausea symptoms, oculomotor symptoms, and the total score. The study offers interesting insights into associations between SS and prior experiences observed by means of high-fidelity real-motion simulations. More research is needed to determine the nature of these associations and their potential usefulness, for example, in helping accident survivors to cope with the distressing or even potentially disabling psychological consequences of accidents.


Assuntos
Condução de Veículo , Simulação por Computador , Enjoo devido ao Movimento/etiologia , Adolescente , Adulto , Idoso , Automóveis , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enjoo devido ao Movimento/epidemiologia , Inquéritos e Questionários
13.
Molecules ; 25(15)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751592

RESUMO

An efficient method of thiol group introduction to the structure of common natural products and synthetic active compounds with recognized biological efficacy such genistein (1), 5,11-dimethyl-5H-indolo[2,3-b]quinolin (2), capecitabine (3), diosgenin (4), tigogenin (5), flumethasone (6), fluticasone propionate (7), ursolic acid methyl ester (8), and ß-sitosterol (9) was developed. In most cases, the desired compounds were obtained easily via two-step processes involving esterification reaction employing S-trityl protected thioacetic acid and the corresponding hydoxy-derivative, followed by removal of the trityl-protecting group to obtain the final compounds. The results of our preliminary experiments forced us to change the strategy in the case of genistein (1), and the derivatization of diosgenin (4), tigogenin (5), and capecitabine (3) resulted in obtaining different compounds from those designed. Nevertheless, in all above cases we were able to obtain thiol-containing derivatives of selected biological active compounds. Moreover, a modelling study for the two-step thiolation of genistein and some of its derivatives was accomplished using the density functional theory (B3LP). A hypothesis on a possible reason for the unsuccessful deprotection of the thiolated genistein is also presented based on the semiempirical (PM7) calculations. The developed methodology gives access to new sulphur derivatives, which might find a potential therapeutic benefit.


Assuntos
Capecitabina/química , Diosgenina/química , Genisteína/química , Nanotecnologia/métodos , Compostos Fitoquímicos/química , Espirostanos/química , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química
14.
Med Pr ; 71(1): 47-58, 2020 Jan 20.
Artigo em Polonês | MEDLINE | ID: mdl-31855217

RESUMO

BACKGROUND: A phenomenon of simulator sickness is measurable in terms of physiological symptoms. The article presents the practical use of the Simulator Sickness Questionnaire (SSQ) in post-exposure research, together with feedback given by the examined drivers. MATERIAL AND METHODS: The study was conducted on the AutoSim AS 1600 simulator, and involved 130 drivers attending preliminary and periodic qualification courses in road transportation. The following tools were used throughout the research: the SSQ by Kennedy et al., translated into Polish by Biernacki et al. (with symptoms including nausea, oculomotor disturbances & disorientation symptoms, and the SSQ total), and a tool evaluating the SSQ (comprehensibility and time consumption on a 1-6 scale). RESULTS: In the study group (N = 130), some statistically significant differences in the SSQ results were observed. Among younger drivers (<29.5 years old) an increased intensity of the simulator sickness symptoms after simulation was recorded (nausea and the SSQ total), and among older drivers (>29.5 years old) - the disorientation symptoms after simulation. The length of sleep and the quality assessment of the conducted task were higher in the asymptomatic groups. Also, the results indicate a positive reception of the tool by the examined individuals (N = 113), with time consumption marked as low (M = 2.44 on a 1-6 scale) and comprehensibility as high (M = 5.62 on a 1-6 scale). CONCLUSIONS: The research indicates the occurrence of simulator sickness symptoms even in simulators, which accurately reflect vehicle movements. The feedback given by the examined individuals, together with the level of involvement in the SSQ use, indicates a positive reception of the tool. Med Pr. 2020;71(1):47-58.


Assuntos
Enjoo devido ao Movimento/etiologia , Sono , Realidade Virtual , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Treinamento por Simulação , Inquéritos e Questionários
15.
Front Pharmacol ; 10: 507, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143124

RESUMO

Acute myeloid leukemia (AML) is a malignant hematopoietic disease with poor prognosis for most patients. Conventional chemotherapy has been the standard treatment approach for AML in the past 40 years with limited success. Although, several targeted drugs were recently approved, their long-term impact on survival of patients with AML is yet to be determined. Thus, it is still necessary to develop alternative therapeutic approaches for this disease. We have previously shown a marked synergistic anti-leukemic effect of two polyphenols, curcumin (CUR) and carnosic acid (CA), on AML cells in-vitro and in-vivo. In this study, we identified another phenolic compound, methyl 4-hydroxycinnamate (MHC), which among several tested phytochemicals could uniquely cooperate with CA in killing AML cells, but not normal peripheral blood mononuclear cells. Notably, our data revealed striking phenotypical and mechanistic similarities in the apoptotic effects of MHC+CA and CUR+CA on AML cells. Yet, we show that MHC is a non-fluorescent molecule, which is an important technical advantage over CUR that can interfere in various fluorescence-based assays. Collectively, we demonstrated for the first time the antileukemic activity of MHC in combination with another phenolic compound. This type of synergistically acting combinations may represent prototypes for novel antileukemic therapy.

16.
Noise Health ; 21(103): 242-247, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32978361

RESUMO

INTRODUCTION: This article discusses the correlation between sensory processing sensitivity (SPS) as a feature of personality and temperament and paramedics' subjective perception of noise inside an ambulance. Description of the theoretical basis of SPS has been strongly depicted. MATERIALS AND METHODS: : Polish translation of SPS 12-item short scale and a survey concerning the subjective perception of noise inside an ambulance have been used in this research. Assessment of noise included its three sources: emergency vehicle siren, resistance of rolling tires and noise produced by diesel engines. 46 paramedics from mobile emergency care units working in Poznan and the Poznan's district have taken part in the research. Paramedics with higher SPS results were selected, creating a highly sensitive people (HSP) group. RESULTS: : When non-HSP people were compared to paramedics from the HSP group, an emergency signal was considered more burdensome for HSP paramedics. The intensity of noise generated by the vehicle's suspension elements and tires was significantly higher in cars more than 3 years old. Older paramedics (≥30 years old) evaluated the intensity as well as burdensomeness of noise generated by suspension's elements and tires, higher than the younger (<30 years old) ones. CONCLUSIONS: : Both paramedics and drivers as occupational groups are liable to noise, which seems to be particularly harmful and burdensome to the HSP group. Further studies should be provided in this area. This may lead to an increase not only in their productivity but also in their quality of life.


Assuntos
Pessoal Técnico de Saúde/psicologia , Percepção Auditiva , Condução de Veículo/psicologia , Ruído Ocupacional , Exposição Ocupacional/análise , Adulto , Ambulâncias , Limiar Auditivo , Feminino , Humanos , Masculino , Polônia
17.
Org Biomol Chem ; 17(2): 354-362, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30548042

RESUMO

tert-Butyl dicarbonate (Boc2O) and ethyl iodide (EtI) reactions with uracil (U), thymine (T) and 6-methyluracil (6-MU) were performed following routine procedures in pyridine/DMF solvents and with DMAP as the catalyst. Among 20 synthesized compounds, a derivative of 6-methyluracil substituted by the Boc-pyridine moiety at the C5 position appeared unexpectedly. The NMR spectra confirmed the molecular structure of all uracil derivatives. Parallel quantum mechanical DFT calculations supported the experimental findings.

18.
Nanomaterials (Basel) ; 8(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544493

RESUMO

The aim of our work was to synthetize of a new analogue of abiraterone-thiolated abiraterone (HS-AB) and design a gold surface monolayer, bearing in mind recent advances in tuning monolayer structures and using them as efficient drug delivery systems. Therapeutic self-assembled monolayers (TSAMs) were prepared by chemically attaching HS-AB to gold surfaces. Their properties were studied by voltammetry and atomic force microscopy (AFM). A gold electrode with immobilized thioglycolic acid (HS-GA) was used for comparison. The surface concentration of HS-AB on the gold surface was 0.572 nmol/cm², determined from the area of the voltammetric reduction peaks (desorption process). The area per one molecule estimated from the voltammetry experiments was 0.291 nmol/cm². The capacity of thus prepared electrode was also tested. The calculated capacity for the HS-AB modified electrode is 2.90 µF/cm². The obtained value indicates that the monolayer on the gold electrode is quite well ordered and well-packed. AFM images show the formation of gold nanoparticles as a result of immersing the HS-AB modified gold electrode in an aqueous solution containing 1 mM HAuCl4·3H2O. These structures arise as a result of the interaction between the HS-AB compound adsorbed on the electrode and the AuCl4- ions. The voltammetric experiments also confirm the formation of gold structures with specific catalytic properties in the process of oxygen reduction.

19.
Molecules ; 23(9)2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30200272

RESUMO

A series of caffeic acid derivatives were synthesized via a modified Wittig reaction which is a very important tool in organic chemistry for the construction of unsaturated carbon⁻carbon bonds. All reactions were performed in water medium at 90 °C. The aqueous Wittig reaction worked best when one unprotected hydroxyl group was present in the phenyl ring. The olefinations in the aqueous conditions were also conducted with good yields in the presence of two unprotected hydroxyl groups. When the number of the hydroxyl groups was increased to three, the reaction yields were worse, and the derivatives 12, 13, and 18 were obtained with 74%, 37%, and 70% yields, respectively. Nevertheless, the Wittig reaction using water as the essential medium is an elegant one-pot synthesis and a greener method, which can be a safe alternative for implementation in organic chemistry. The obtained compounds were tested for their antioxidant activity, and 12, 13, and 18 showed the highest activities. Moreover, all synthesized compounds displayed no cytotoxicity, and can therefore be used in the pharmaceutical or cosmetic industry.


Assuntos
Antioxidantes/síntese química , Antioxidantes/farmacologia , Ácidos Cafeicos/síntese química , Ácidos Cafeicos/farmacologia , Antioxidantes/química , Ácidos Cafeicos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos , Humanos , Estrutura Molecular , Oxirredução/efeitos dos fármacos
20.
Carbohydr Res ; 460: 19-28, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29501860

RESUMO

An efficient methodology of the glycosylation process of a secondary plant metabolite (R-Danshensu) and its enantiomer by sugar and 2-deoxy sugar donors was developed. The overall synthesis of the new sugar derivatives involved two steps, starting from the previously synthesized protected R and S Danshensu (1 and 2). The deoxy sugar derivatives of R and S Danshensu were obtained from available tri-O-acetyl-2-deoxy-D-glucal and di-O-acetyl-2-deoxy-D-ramnal. The direct glycosylation of 1 and 2 using glycal activation by an acid catalyst in all cases led to the α-anomers of deoxy sugar derivatives with good yields. As a result, a novel group of sugar and deoxy sugar conjugates with optically pure polyphenolic acids was successfully synthesized and their cytotoxic profile against two cancer cell lines was tested. An advantageous ADME profile and antiproliferative data classified this new group of compounds as a promising scaffold for further modification of more potent and selective anticancer agents.


Assuntos
Desoxiaçúcares/química , Polifenóis/química , Glicosilação , Estereoisomerismo
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