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1.
Int J Mol Sci ; 25(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339017

RESUMO

The reaction of (ortho-acetalaryl)arylmethanols with various phosphines PR1R2R3 (R1 = R2 = R3 = Ph; R1 = R2 = Ph, R3 = Me and R1 = R2 = Me, R3 = Ph) under acidic conditions (e.g., HCl, HBF4, TsOH) unexpectedly led to the formation of (10-hydroxy-9,10-dihydroanthr-9-yl)phosphonium salts instead of the corresponding anthryl phosphonium salts. The cyclization occurred according to the Friedel-Crafts mechanism but without the usually observed Bradsher dehydration, giving cyclic products in the form of cis/trans isomers and their conformers. In case of electron-rich and less-hindered dimethylphenylphosphine, all four stereoisomers were recorded in 31P{1H} NMR spectra, while for the other phosphines, only the two most stable cis/trans stereoisomers were detected. This study was supported by DFT and NCI calculations in combination with FT-IR analysis.


Assuntos
Fosfinas , Sais , Humanos , Estrutura Molecular , Ciclização , Desidratação , Espectroscopia de Infravermelho com Transformada de Fourier , Fosfinas/química
2.
Molecules ; 28(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37687251

RESUMO

The functionalization of the aromatic backbone allows the improvement of the electrical properties of acene molecules in the amorphous layered structures of organic thin films. In the present work, we discuss the electric properties of the stable, amorphous, vacuum-deposited films prepared from five highly substituted 10-RO-acenes of various electronic properties, i.e., two extreme electron-donor (1,3-dioxa-cyclopenta[b]) anthracenes with all RO substituents, two anthracene carbaldehydes and one benzo[b]carbazole carbaldehyde possessing both electron-donor and acceptor substituents. The hole mobility data were obtained using subsequent steady state space charge limited currents (SCLC) and Time of Flight (TOF) measurements, performed on the same sample and these were then compared with the results of theoretical hole mobility calculations obtained using the Density Functional Theory (DFT) quantum-chemical calculations using the Marcus-Hush theory. The study shows a good agreement between the theoretical and experimental values which allows for the quick and quantitative estimation of Einstein's mobility values for highly substituted 10-RO anthracene and benzo[b]carbazole based on chemical calculations. This agreement also proves that the transport of holes follows the hopping mechanism. The theoretical calculations indicate that the reorganization energy plays a decisive role in the transport of holes in the amorphous layers of highly substituted hetero(acenes).

3.
Molecules ; 28(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37764366

RESUMO

The ecotoxicological impact of pharmaceuticals has received considerable attention, primarily focusing on active pharmaceutical ingredients (APIs) while largely neglecting the potential hazards posed by pharmaceutical excipients. Therefore, we analyzed the ecotoxicity of 16 commonly used pharmaceutical excipients, as well as 26 API-excipient and excipient-excipient mixtures utilizing the Microtox® test. In this way, we assessed the potential risks that pharmaceutical excipients, generally considered safe, might pose to the aquatic environment. We investigated both their individual ecotoxicity and their interactions with tablet ingredients using concentration addition (CA) and independent action (IA) models to shed light on the often-overlooked ecotoxicological consequences of these substances. The CA model gave a more accurate prediction of toxicity and should be recommended for modeling the toxicity of combinations of drugs with different effects. A challenge when studying the ecotoxicological impact of some pharmaceutical excipients is their poor water solubility, which hinders the use of standard aquatic ecotoxicity testing techniques. Therefore, we used a modification of the Microtox® Basic Solid Phase protocol developed for poorly soluble substances. The results obtained suggest the high toxicity of some excipients, i.e., SLS and meglumine, and confirm the occurrence of interactions between APIs and excipients. Through this research, we hope to foster a better understanding of the ecological impact of pharmaceutical excipients, prompting the development of risk assessment strategies within the pharmaceutical industry.


Assuntos
Meio Ambiente , Excipientes , Excipientes/toxicidade , Medição de Risco , Indústria Farmacêutica , Preparações Farmacêuticas
4.
J Clin Med ; 12(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37510750

RESUMO

Nintedanib is a disease-modifying agent licensed for the treatment of IPF. Data on Polish experience with nintedanib in IPF are lacking. The present study aimed to describe the safety and efficacy profiles of nintedanib in a large real-world cohort of Polish patients with IPF. This was a multicenter, retrospective, observational study of IPF patients treated with nintedanib between March 2018 and October 2021. Data collection included baseline clinical characteristics, results of pulmonary function tests (PFTs), and a six-minute walk test (6MWT). Longitudinal data on PFTs, 6MWT, adverse drug reactions (ADRs), and treatment persistence were also retrieved. A total of 501 patients (70% male) with a median age of 70.9 years (IQR 65-75.7) were included in this study. Patients were followed on treatment for a median of 15 months (7-25.5). The majority of patients (66.7%) were treated with the full recommended dose of nintedanib and 33.3% of patients were treated with a reduced dose of a drug. Intermittent dose reductions or drug interruptions were needed in 20% of patients. Over up to 3 years of follow-up, pulmonary function remained largely stable with the minority experiencing disease progression. The most frequent ADRs included diarrhea (45.3%), decreased appetite (29.9%), abdominal discomfort (29.5%), weight loss (32.1%), nausea (20.8%), fatigue (19.2%), increased liver aminotransferases (15.4%), and vomiting (8.2%). A total of 203 patients (40.5%) discontinued nintedanib treatment due to diverse reasons including ADRs (10.2%), death (11.6%), disease progression (4.6%), patient's request (6.6%), and neoplastic disease (2.2%). This real-world study of a large cohort of Polish patients with IPF demonstrates that nintedanib therapy is safe, and is associated with acceptable tolerance and disease stabilization. These data support the findings of previously conducted clinical trials and observational studies on the safety and efficacy profiles of nintedanib in IPF.

5.
Molecules ; 27(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36235148

RESUMO

This comprehensive review, covering the years 1968-2022, is not only a retrospective investigation of a certain group of linearly fused aromatics, called acenes, but also a presentation of the current state of the knowledge on the synthesis, reactions, and applications of these compounds. Their characteristic feature is substitution of the aromatic system by one, two, or three organophosphorus groups, which determine their properties and applications. The (PIII, PIV, PV) phosphorus atom in organophosphorus groups is linked to the acene directly by a P-Csp2 bond or indirectly through an oxygen atom by a P-O-Csp2 bond.


Assuntos
Benzeno , Fósforo , Oxigênio/química , Fósforo/química , Estudos Retrospectivos
7.
Materials (Basel) ; 14(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201740

RESUMO

While few studies show only symmetrical and poorly mono-SOn (n = 0-2) substituted acenes, in this study, we present a synthesis of a new group of unsymmetrical, significantly substituted derivatives, which revealed unique photophysical properties. Both sulfides (S), sulfoxides (SO) and sulfones (SO2) showed very high photochemical stabilities, unusual for these groups, during UV-irradiation at 254/365 nm (air O2 and Ar), which was higher than any found in the literature. For the (S)/(SO) series (254 nm), the stabilities of 80-519 min. (air O2 and Ar) were found. At 365 nm, stabilities of 124-812 min./(air O2) for (S)/(SO) and higher for (SO2) were observed. Photoluminescence lifetimes of (SOn) of the lower anthryl symmetry remained in the following order: (SO2) < (S) < (SO); those with full symmetry were in the following order: (S) < (SO) < (SO2). The enhanced photostability was explained with DFT/MS/Hammett's constants, which showed the leading role of the SOn groups in stabilization of HOMO/LUMO frontier orbitals. The SOn (n = 0-2) substituted acenes turned out to be tunable violet/blue/green emitters by oxidation of S atoms and the introduction of rich substitution.

8.
Mol Pharm ; 18(5): 1970-1984, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33792313

RESUMO

Physicochemical properties, in particular solubility and the associated bioavailability, are key factors in determining efficacy of poorly water-soluble drugs, which constitute 40% of new drugs in the market, and improving them is an important challenge for modern pharmacy. A recent strategy to achieve this goal is formation of stable co-amorphous solid dispersions with co-formers of low molecular weight. Here, the amorphization strategy was applied for low-soluble anti-hypertensive valsartan (VAL), an angiotensin II receptor blocker, and nicotinamide, which exhibits lung- and cardio-protective effects. Through interactions with the renin-angiotensin-aldosteron system, VAL may be used to treat both hypertension and the current pandemic coronavirus SARS-CoV-2 infection. Using mechanochemical and liquid- and solid-state approaches, solvated co-amorphous solid dispersions of VAL with nicotinamide were obtained. They were characterized by spectroscopic, thermal, and X-ray analyses. The density functional theory, quantum theory of atoms in molecules, and non-covalent interaction index calculations revealed the presence of two types of hydrogen bonds between VAL and NIC (i.e., N-H···O and O-H···O). One of them had a partially covalent character, which caused conformational changes in the flexible VAL molecule, restricting contribution of the tetrazolyl N-H donor and thus limiting the possibility of co-crystal formation. The recognized VAL/NIC1- and VAL/NIC2-type heterodimeric interactions were responsible for the excellent durability of the solid compositions and up to 24-fold better solubility than VAL alone. The synthesized dispersions constitute a new class of dually acting drugs, containing an active pharmaceutical ingredient (VAL) and supporting nutraceutical (nicotinamide).


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Anti-Hipertensivos/química , Tratamento Farmacológico da COVID-19 , Química Farmacêutica/métodos , Portadores de Fármacos/química , Niacinamida/química , Valsartana/química , Anti-Hipertensivos/síntese química , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Humanos , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Teoria Quântica , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Molecules ; 26(8)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924691

RESUMO

Amygdalin (d-Mandelonitrile 6-O-ß-d-glucosido-ß-d-glucoside) is a natural cyanogenic glycoside occurring in the seeds of some edible plants, such as bitter almonds and peaches. It is a medically interesting but controversial compound as it has anticancer activity on one hand and can be toxic via enzymatic degradation and production of hydrogen cyanide on the other hand. Despite numerous contributions on cancer cell lines, the clinical evidence for the anticancer activity of amygdalin is not fully confirmed. Moreover, high dose exposures to amygdalin can produce cyanide toxicity. The aim of this review is to present the current state of knowledge on the sources, toxicity and anticancer properties of amygdalin, and analytical methods for its determination in plant seeds.


Assuntos
Amigdalina/química , Glicosídeos/química , Cianeto de Hidrogênio/química , Sementes/química , Animais , Humanos
10.
Materials (Basel) ; 13(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114241

RESUMO

The interest in functional materials possessing improved properties led to development of new methods of their synthesis, which allowed to obtain new molecular arrangements with carbon and heteroatom motifs. Two of the classical reactions of versatile use are the Friedel-Crafts and the Bradsher reactions, which in the new heteroatomic versions allow to replace ring carbon atoms by heteroatoms. In the present work, we review methods of synthesis of C-S and C-P bonds utilizing thia- and phospha-Friedel-Crafts-Bradsher cyclizations. Single examples of C-As and lack of C-Se bond formation, involving two of the closest neighbors of P and S in the periodic table, have also been noted. Applications of the obtained π-conjugated molecules, mainly as semiconducting materials, flame retardants, and resins hardeners, designed on the basis of five- and six-membered cyclic molecules containing ring phosphorus and sulfur atoms, are also included. This comprehensive review covers literature up to August 2020.

11.
BMC Pulm Med ; 20(1): 122, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366291

RESUMO

BACKGROUND: Pirfenidone is an antifibrotic agent approved for the treatment of idiopathic pulmonary fibrosis (IPF). The drug is available for Polish patients with IPF since 2017. The PolExPIR study aimed to describe the real-world data (RWD) on the Polish experience of pirfenidone therapy in IPF with respect to safety and efficacy profiles. METHODS: This was a multicentre, retrospective, observational study collecting clinical data of patients with IPF receiving pirfenidone from January 2017 to September 2019 across 10 specialized pulmonary centres in Poland. Data collection included baseline characteristics, pulmonary function tests (PFTs) results and six-minute walk test (6MWT). Longitudinal data on PFTs, 6MWT, adverse drug reactions (ADRs), treatment persistence, and survival were also collected up to 24 months post-inclusion. RESULTS: A total of 307 patients receiving pirfenidone were identified for analysis. The mean age was 68.83 (8.13) years and 77% were males. The median time from the first symptoms to IPF diagnosis was 15.5 (9.75-30) months and from diagnosis to start of pirfenidone treatment was 6 (2-23) months. Patients were followed on treatment for a median of 17 (12-22.75) months. Seventy-four patients (24.1%) required dose adjustments and 35 (11.4%) were chronically treated with different than the full recommended dose. A total of 141 patients (45.92%) discontinued therapy due to different reasons including ADRs (16.61%), death (8.79%), disease progression (6.51%), patient's own request (5.54%), neoplastic disease (3.91%) and lung transplantation (0.33%). Over up to 24 months of follow-up, the pulmonary function remained largely stable. The median annual decline in forced vital capacity (FVC) during the first year of pirfenidone therapy was -20 ml (-200-100) and during the second year was -120 ml (-340-30). Over a study period, 33 patients (10.75%) died. CONCLUSIONS: The PolExPIR study is a source of longitudinal RWD on pirfenidone therapy in the Polish cohort of patients with IPF supporting its long-term acceptable safety and efficacy profiles and reinforce findings from the previous randomised clinical trials and observational studies.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Fibrose Pulmonar Idiopática/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Piridonas/uso terapêutico , Idoso , Progressão da Doença , Feminino , Humanos , Fibrose Pulmonar Idiopática/cirurgia , Pulmão/fisiopatologia , Transplante de Pulmão/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Polônia , Testes de Função Respiratória , Estudos Retrospectivos , Resultado do Tratamento , Teste de Caminhada
12.
Ultrason Sonochem ; 58: 104640, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31450342

RESUMO

Two heteroatom-variants of the Friedel-Crafts/Bradsher cyclization of o-acetalaryl(aryl)methyl ethers and o-dithioacetalaryl(aryl)methyl thioethers, have been realized with the ultrasound assistance. The environmentally friendly "oxo-variant" (Oxo-F-C/B), proceeding in a medium containing mineral acid and a large amount of water (HClaq/CH3CN) led to a very efficient formation of RO-substituted (hetero)acenes in less than 5 min. In the "thio-variant" (Thio-F-C/B), o-dithioacetalaryl(aryl)methyl thioethers underwent ultrasound-assisted cyclization in nonaqueous medium (FeCl3/KI/EtOH) in less than 25 min., in lower yields than in the "oxygen variant" to give RS-substituted (hetero)acenes. The RO-(hetero)acenes cyclized at 25-60 °C in aqueous media but did not cyclize in organic solvents while the RS-(hetero)acenes required higher temperatures 55-60 °C and cyclized in organic solvents but did not react in aqueous media. The acceleration of the ultrasound-assisted reactions compared to the reactions carried out under silent conditions exceeded 7500 times in the most effective example of the oxo-variant and on average 2 times for the thio-variant. The plausible reaction mechanisms under ultrasound and silent conditions have been proposed. The ultrasonic mechanism involves disturbing of solvation layers and formation of the reactive ("naked") carbocations upon operation of the shock wave produced by the bubble collapse. The o-acetalaryl(aryl)methyl ethers underwent a selective ultrasound-assisted deacetalization to give o-formylaryl(aryl)methyl ethers, without subsequent cyclization under the acidic reaction conditions.

13.
Chemistry ; 25(62): 14148-14161, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31432602

RESUMO

The highly substituted mono-aryl/alkylthio-(hetero)acenes prepared in this study have been found to be thermally more stable (Tdecomp. =331-354 °C) than the known di-aryl/alkylthio-substituted acenes by an average of 25 °C. They are also much more photostable at 254 and 365 nm (in both argon and air) than the parent anthracene and other reported anthracenes. The most photostable aryl/alkylthio-anthracenes at 254 nm were found to be 60-70 (in air) and 130 (in argon) times more stable in solution than the unsubstituted anthracene, and much more stable than known EDG/EWG-substituted anthracenes (EDG=electron-donating group, EWG=electron-withdrawing group) with an extended aromatic core. Furthermore, the acenes showed significantly higher photostability at 365 nm in both air and argon. The anthracenes were obtained by the novel thio-Friedel-Crafts/Bradsher cyclization reaction of hitherto unknown [o-(1,3-dithian-2-yl)aryl](aryl)methyl thioethers. The developed approach provides a general access to mono-aryl/alkylthio-substituted (hetero)acene frameworks containing at least three fused (hetero)aromatic rings. The characteristic feature of this approach, which leads to highly substituted acenes, is that the substituents, unlike in other methods, may be introduced at an early stage of the synthesis. DFT and TD-DFT calculations confirmed the stabilizing role of the aryl/alkylthio substituent in the mono-aryl/alkylthio-substituted anthracenes, which are the most stable anthracenes prepared to date. Their high photostability is mainly due to the quenching of singlet oxygen by the acene and the quenching of the acene S1 state by molecular oxygen.

14.
J Org Chem ; 84(5): 2619-2625, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30698971

RESUMO

The first solvent- and catalyst-free procedure for the Michaelis-Arbuzov reaction under flow conditions was developed. A variety of alkylphosphonic esters could be obtained using this protocol starting from the corresponding trialkyl phosphites and even catalytic amounts of alkyl halides with very short reaction times (8.33-50 min) and excellent conversions. In general, this protocol works effectively when the alkyl halide is used in catalytic amounts as low as 5-10% only if it concerns the synthesis of homo alkylphosphonates. One equivalent and an excess of alkyl halides should be used in the reaction with alkyl phosphite if the alkyl group of the selected substrates differ. Thus, it provides a sustainable, fast alternative to the existing methods for the preparation of alkylphosphonates. The isolation of the reaction products is straightforward due to the lack of solvents and a high purity of the obtained products (conv ≥ 99%), and notably, in the catalytic procedures there are only traces of alkyl halides formed after the reaction is complete. The reactions conducted using a glass microreactor chip with an internal volume of 250 µL allow the production of 1.6-1.95 g of organophosphorus esters per hour.

15.
Beilstein J Org Chem ; 14: 1229-1237, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977391

RESUMO

We present a successful deoxygenation reaction of ortho-1,3-dithianylaryl(aryl)methanols which enables a selective removal of the secondary hydroxy group in presence of the 1,3-dithianyl moiety under reductive conditions. This reaction proceeds well with ZnI2/Na(CN)BH3 in dichloroethane or benzene for both unsubstituted and substituted aryls (by electron-rich groups). This is leading to formyl-protected diarylmethanes with potential application in the synthesis of new pharmaceuticals and optoelectronic materials. This synthetic approach gives an access to a wide variety of functionalized ortho-1,3-dithianylaryl(aryl)methanes in 26-95% yields and is recommended for the substrates containing sulfur atoms, for which transition metal-induced reactions fail.

16.
J Plant Physiol ; 215: 91-99, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28618259

RESUMO

Plant-derived smoke - butenolide, called at present karrikin 1 (KAR1) is known as an important inductor of seed germination and seedling growth. In this study, tricyclic butenolides were synthesized and their effects on germination of dormant and non-dormant Avena fatua caryopses were compared, as were also their effects versus those of KAR1 on seedling growth. KAR1 was found to be most effective and to completely remove dormancy. Butenolides, rac-8 and (S)-8a, showed a low stimulatory effect on germination of dormant caryopses, visible only when applied at very high concentrations. These compounds used at concentrations 100 times those of KAR1 similarly increased the speed of germination and vigor of non-dormant caryopses. Likewise, growth of coleoptiles and their fresh weight were increased by KAR1 as well as by rac-8 and (S)-8a to a similar value. KAR1 and rac-8 were more effective than (S)-8a in increasing root growth. The results shown indicate that the presence of an aromatic ring in the absence of methyl group at C3 induced a much lower, or a similar, effect on germination of dormant and non-dormant Avena fatua caryopses and seedling growth compared to KAR1, but only when used at much higher concentrations. The simultaneous presence of a methyl group at C3 and an aromatic ring in the compound rac-7 exerted only a slight effect on the root growth.


Assuntos
4-Butirolactona/análogos & derivados , Furanos/farmacologia , Piranos/farmacologia , 4-Butirolactona/síntese química , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Avena/efeitos dos fármacos , Avena/metabolismo , Cotilédone/efeitos dos fármacos , Cotilédone/metabolismo , Germinação/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/metabolismo
17.
Beilstein J Org Chem ; 13: 451-494, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28382183

RESUMO

This comprehensive review describes methods for the preparation of 1-indanones published in original and patent literature from 1926 to 2017. More than 100 synthetic methods utilizing carboxylic acids, esters, diesters, acid chlorides, ketones, alkynes, alcohols etc. as starting materials, have been performed. This review also covers the most important studies on the biological activity of 1-indanones and their derivatives which are potent antiviral, anti-inflammatory, analgesic, antimalarial, antibacterial and anticancer compounds. Moreover, they can be used in the treatment of neurodegenerative diseases and as effective insecticides, fungicides and herbicides.

18.
Org Biomol Chem ; 14(5): 1822-30, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26750755

RESUMO

In this paper, we have described the first total synthesis of (±)-epithuriferic acid methyl ester from non-natural sources, in four steps (20% overall yield). The key step involves the Diels-Alder reaction of isobenzofuran with methyl 3-(dimethoxyphosphoryl)acrylate which is controlled by "ortho" regio- and endo stereoselectivities due to the COOMe group.


Assuntos
Benzofuranos/química , Carbazóis/síntese química , Reação de Cicloadição , Naftalenos/síntese química , Carbazóis/química , Estrutura Molecular , Naftalenos/química , Estereoisomerismo
19.
J Plant Physiol ; 176: 169-79, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25618514

RESUMO

Avena fatua L. caryopses did not germinate at 20 °C in darkness because they were dormant. However, they were able to germinate in the presence of karrikinolide (KAR1), a key bioactive compound present in smoke, and also in the presence of gibberellin A3 (GA3), a commonly known stimulator of seed germination. The aim of this study was to collect information on a possible relationship between the above regulators and abscisic acid (ABA), reactive oxygen species (ROS) and ROS scavenging antioxidants in the regulation of dormant caryopses germination. KAR1 and GA3 caused complete germination of dormant A. fatua caryopses. Hydrogen peroxide (H2O2), compounds generating the superoxide (O2(·-)), i.e. menadione (MN), methylviologen (MV) and an inhibitor of catalase activity, aminotriazole (AT), induced germination of dormant caryopses. KAR1, GA3, H2O2 and AT decreased ABA content in embryos. Furthermore, KAR1, GA3, H2O2, MN, MV and AT increased α-amylase activity in caryopses. The effect of KAR1 and GA3 on ROS (H2O2, O2(·-)) and activities of the superoxide dismutase (SOD) and catalase (CAT) were determined in caryopses, embryos and aleurone layers. SOD was represented by four isoforms and catalase by one. In situ localization of ROS showed that the effect of KAR1 and GA3 was associated with the localization of hydrogen peroxide mainly on the coleorhiza. However, the superoxide was mainly localized on the surface of the scutellum. Superoxide was also detected in the protruding radicle. Germination induction of dormant caryopses by KAR1 and GA3 was related to an increasing content of H2O2, O2(·-)and activities of SOD and CAT in embryos, thus ROS homeostasis was probably required for the germination of dormant caryopses. The above regulators increased the content of ROS in aleurone layers and decreased the activities of SOD and CAT, probably leading to the programmed cell death. The presented data provide new insights into the germination induction of A. fatua dormant caryopses by KAR1 and also by GA3. In A. fatua, KAR1 or GA3 is included in the induction germination of dormant caryopses through regulation level of ABA in embryos and ROS-antioxidant status both in embryos and aleurone layers.


Assuntos
Antioxidantes/metabolismo , Avena/embriologia , Furanos/farmacologia , Germinação/efeitos dos fármacos , Giberelinas/farmacologia , Dormência de Plantas/efeitos dos fármacos , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sementes/embriologia , Ácido Abscísico/metabolismo , Amitrol (Herbicida)/farmacologia , Avena/efeitos dos fármacos , Avena/enzimologia , Catalase/antagonistas & inibidores , Catalase/metabolismo , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/farmacologia , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Paraquat/farmacologia , Sementes/efeitos dos fármacos , Sementes/enzimologia , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Vitamina K 3/farmacologia , alfa-Amilases/metabolismo
20.
J Org Chem ; 71(7): 2899-902, 2006 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-16555852

RESUMO

10-Benzyloxy-1,2,3-trimethoxy-6,7-(methylene-1,3-dioxy)anthracene as a potential material for molecular electronics was synthesized from the O-benzyl-protected diarylmethanol derivative containing the 1,3-dioxyethylene acetal function via a one-pot procedure under acidic conditions (1 N HCl, methanol, 60 h) in 60% yield. The replacement of methanol for benzene resulted in hydrolysis of the acetal function in 96% yield.

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