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1.
Chem Commun (Camb) ; 55(73): 10920-10923, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31441463

RESUMO

The development of new NIR-II fluorophores, particularly those with facile syntheses, high fluorescence quantum yields, and stable and tunable photophysical properties, is challenging. Herein, we report a new class of small molecular NIR-II fluorophores based on aza-dipyrromethene boron difluoride (aza-BODIPY) dyes. We demonstrate promising photophysical properties of these dyes, such as large Stokes shift, superior photostability, and good fluorescence brightness as nanoparticles in aqueous solution. Because of these properties and high resolution and deep penetration NIR-II imaging ability, the aza-BODIPY based dyes show great potential as NIR-II imaging agents.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Imagem Óptica/métodos , Pirróis/química , Animais , Compostos de Boro/síntese química , Compostos de Boro/efeitos da radiação , Compostos de Boro/toxicidade , Linhagem Celular Tumoral , Teoria da Densidade Funcional , Desenho de Drogas , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Raios Infravermelhos , Camundongos , Modelos Químicos , Nanopartículas/química , Poloxâmero/química , Pirróis/síntese química , Pirróis/efeitos da radiação , Pirróis/toxicidade
3.
Chemistry ; 25(58): 13354-13362, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31338861

RESUMO

New L-shaped fluorophores possessing five conjugated rings have been synthesized through a four-step procedure involving diketopyrrolopyrrole synthesis and its double N-alkylation, followed by trimethylsilyl bromide-mediated rearrangement to thieno[2,3-f]isoindole-5,8-dione and an intramolecular Friedel-Crafts reaction. In comparison with the parent isoindolediones and π-expanded diketopyrrolopyrroles, these new dyes show red-shifted absorption and emission (up to ≈630 nm). Their structural rigidity is responsible for both the observed small Stokes shifts and large fluorescence quantum yields. Tissue imaging studies revealed that these new dyes show advantageous features including minimal autofluorescence interference and pronounced solvent-sensitive emission. Interestingly, there is a fundamental difference between a dye possessing an amino group and its analog bearing an N-alkyl substituent. The former dye under two-photon excitation at 900 nm gives bright images whereas its N-alkylated counterpart does not. A new type of membrane localization has been discovered by an N-alkylated isoindoledione possessing a benzofuryl substituent. In spite of the fact that the fluorescence quantum yield of this dye in a range of solvents is rather low, it does stain cell membranes exclusively. This new mode of cellular staining opens the door towards further development of membrane staining dyes.


Assuntos
Corantes Fluorescentes/química , Isoindóis/química , Células A549 , Animais , Humanos , Cetonas/síntese química , Camundongos Endogâmicos BALB C , Imagem Óptica , Pirróis/síntese química , Compostos de Trimetilsilil/química
4.
Eur J Med Chem ; 179: 591-607, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279293

RESUMO

Antibody-drug conjugates (ADCs) containing pyrrolobenzodiazepine (PBD) dimers are currently being evaluated in human oncology clinical trials with encouraging results. To further improve the therapeutic window, next-generation PBD drug-linker design has focused on the inclusion of additional tumor-selective triggers and use of lower-potency PBDs. ß-Glucuronidase is a well-known target for discovery prodrugs due to increased presence in tumor cells and microenvironment. In this study, a ß-glucuronidase cleavable cap was investigated at the PBD N10-position and compared with corresponding free imine ADCs. SG3600 (glucuronide) ADCs showed in vitro and in vivo efficacy/tolerability comparable to SG3400 (imine) ADCs, and good 50% inhibitory concentration differentials were observed in vitro between control non-antigen-targeted ADCs and targeted ADCs. Dependence on ß-glucuronidase for SG3600 activity was demonstrated through CRISPRCas9 knockdown studies and addition of exogenous ß-glucuronidase. SG3600 showed better serum stability, improved conjugation efficiency and was able to reach high drug-to-antibody ratio without aggregation.


Assuntos
Benzodiazepinas/farmacologia , Dipeptídeos/farmacologia , Glucuronídeos/farmacologia , Imunoconjugados/farmacologia , Pirróis/farmacologia , Benzodiazepinas/síntese química , Benzodiazepinas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dipeptídeos/química , Relação Dose-Resposta a Droga , Glucuronídeos/química , Humanos , Imunoconjugados/química , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
5.
Eur J Med Chem ; 178: 329-340, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31200235

RESUMO

A novel series of 6-substituted pyrrolo[2,3-d]pyrimidines with reversed amide moieties from the lead compound 1a were designed and synthesized as nonclassical antifolates and as potential antitumor agents. Target compounds 1-9 were successfully obtained through two sequential condensation reactions from the key intermediate 2-amino-6-(2-aminoethyl)-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-one. In preliminary antiproliferation assay, all compounds demonstrated submicromolar to nanomolar inhibitory effects against KB tumor cells, whereas compounds 1-3 also exhibited nanomolar antiproliferative activities toward SW620 and A549 cells. In particular, compounds 1-3 were significantly more potent than the positive control methotrexate (MTX) and pemetrexed (PMX) to A549 cells. The growth inhibition induced cell cycle arrest at G1-phase with S-phase suppression. Along with the results of nucleoside protection assays, inhibition assays of dihydrofolate reductase (DHFR) clearly elucidated that the intracellular target of the designed compounds was DHFR. Molecular modeling studies suggested two binding modes of the target compounds with DHFR.


Assuntos
Antineoplásicos/farmacologia , Desenho de Drogas , Antagonistas do Ácido Fólico/farmacologia , Ácido Fólico/metabolismo , Pirimidinas/farmacologia , Pirróis/farmacologia , Tetra-Hidrofolato Desidrogenase/metabolismo , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Antagonistas do Ácido Fólico/síntese química , Antagonistas do Ácido Fólico/química , Humanos , Células KB , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
6.
Eur J Med Chem ; 178: 500-514, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202995

RESUMO

Antibiotic resistance represents a major threat worldwide. Gram-positive and Gram-negative opportunistic pathogens are becoming resistant to all known drugs mainly because of the overuse and misuse of these medications and the lack of new antibiotic development by the pharmaceutical industry. There is an urgent need to discover structurally innovative antibacterial agents for which no pre-existing resistance is known. This work describes the identification, synthesis and biological evaluation of a novel series of 1,5-diphenylpyrrole compounds active against a panel of ESKAPE bacteria. The new compounds show high activity against both wild type and drug-resistant Gram + ve and Gram-ve pathogens at concentrations similar or lower than levofloxacin. Microbiology studies revealed that the plausible target of the pyrrole derivatives is the bacterial DNA gyrase, with the pyrrole derivatives displaying similar inhibitory activity to levofloxacin against the wild type enzyme and retaining activity against the fluoroquinolone-resistant enzyme.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Pirróis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HEK293 , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
7.
Molecules ; 24(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067638

RESUMO

Diketopyrrolopyrrole (DPP) is an important type of π-conjugated building block for high-performance organic electronic materials. DPP-based conjugated materials are usually synthesized via Suzuki, Stille, or Negishi cross-coupling reactions, which require organometallic precursors. In this paper, a series of novel phenyl-cored DPP molecules, including five meta-phenyl-cored molecules and four para-phenyl-cored molecules, have been synthesized in moderate to good yields, in a facile manner, through the Pd-catalyzed direct arylation of C-H bonds, and their optoelectrical properties have been investigated in detail. All new molecules have been fully characterized by NMR, MALDI-TOF MS, elemental analysis, UV-visible spectroscopy, and cyclic voltammetry. This synthetic strategy has evident advantages of atom- and step-economy and low cost, compared with traditional cross-coupling reactions.


Assuntos
Estrutura Molecular , Polímeros/síntese química , Pirróis/síntese química , Catálise , Eletrônica , Polímeros/química , Pirróis/química
8.
Org Lett ; 21(10): 3610-3614, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31033299

RESUMO

An expedient synthesis of tetrahydroindoles and tetrahydrocyclopenta[ b]pyrroles, highlighted by Brønsted acid catalyzed formal [2 + 2 + 1] annulation reaction, is reported. Using three readily accessible reaction components, i.e., an electrophilic species in silyloxyallyl cations and two distinct nucleophiles in silylenol ethers and amines, our chemistry enables the assembly and functionalization of these biologically important N-heterocycles in a highly modular manner.


Assuntos
Aminas/química , Éteres/química , Indóis/síntese química , Pirróis/síntese química , Catálise , Indóis/química , Estrutura Molecular , Pirróis/química
9.
Molecules ; 24(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013677

RESUMO

An efficient arylation of SEM-protected pyrroles by the Suzuki-Miyaura coupling reaction has been developed. The reaction can be carried out under mild conditions to provide aryl-substituted pyrroles in moderate to excellent yields. The scope and limitations of the methodology were evaluated, and the reaction was tolerant of a wide range of functionalities. Compared to the reported methods, the protocol has some advantages, such as commercially available materials, no debrominated by-products being formed, and the amine-protecting group being stable under the reaction conditions. The synthetic utility of the product has also been demonstrated, with several common transformations of the aryl-substituted pyrrole product being conducted. This protocol will offer the opportunity to explore other metal-catalyzed cross-coupling reactions employing SEM-protected pyrroles.


Assuntos
Pirróis/química , Pirróis/síntese química , Catálise , Estrutura Molecular
10.
Nat Commun ; 10(1): 1501, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940810

RESUMO

Riboswitches are naturally occurring RNA aptamers that regulate gene expression by binding to specific small molecules. Riboswitches control the expression of essential bacterial genes and are important models for RNA-small molecule recognition. Here, we report the discovery of a class of synthetic small molecules that bind to PreQ1 riboswitch aptamers. These molecules bind specifically and reversibly to the aptamers with high affinity and induce a conformational change. Furthermore, the ligands modulate riboswitch activity through transcriptional termination despite no obvious chemical similarity to the cognate ligand. X-ray crystallographic studies reveal that the ligands share a binding site with the cognate ligand but make different contacts. Finally, alteration of the chemical structure of the ligand causes changes in the mode of RNA binding and affects regulatory function. Thus, target- and structure-based approaches can be used to identify and understand the mechanism of synthetic ligands that bind to and regulate complex, folded RNAs.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Pirimidinonas/química , Pirimidinonas/metabolismo , Pirróis/química , Pirróis/metabolismo , Riboswitch , Aptâmeros de Nucleotídeos/genética , Cristalografia por Raios X , Ligantes , Conformação de Ácido Nucleico , Pirimidinonas/síntese química , Pirróis/síntese química , Dobramento de RNA
11.
Int J Biol Macromol ; 133: 1299-1310, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30940586

RESUMO

Pseudomonas fluorescens lipase (PFL) was covalently immobilized on carbon nanofiber (CNF) using 1­ethyl­3­[3­dimethylaminopropyl] carbodiimide (EDC)/N­hydroxysuccinimide (NHS). Surface functionalization of carbon nanofiber augments dispersibility as well as efficiency of covalent immobilization. Crucial parameters for immobilization such as pH, enzyme-support ratio, reaction time and mixing rate were optimized using one factor at a time (OFAT) approach. The nanobiocatalyst prepared under optimized conditions demonstrated a ten-fold increase in enzyme activity and the advantage of high thermal stability (up to 85 °C) along with 10 cycles of reusability. Subsequently practical application of the nanobiocatalyst was explored in the kinetic resolution of racemic 1­phenylethanol into (S)­1­phenylethanol [C = 49.1%, eep = 99.5%, ees = 98.5% and E value = 151.4] followed by Mitsunobu reaction with a substituted pyrrole, giving an enantiopure (R)-carboetomidate analogue (yield = 83%).


Assuntos
Carbono/química , Enzimas Imobilizadas/química , Lipase/química , Nanofibras/química , Pseudomonas fluorescens/enzimologia , Pirróis/química , Pirróis/síntese química , Biocatálise , Técnicas de Química Sintética , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Lipase/metabolismo , Reciclagem , Estereoisomerismo
12.
Curr Top Med Chem ; 19(9): 741-752, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30931859

RESUMO

Background & Introduction: Pyrrolobenzodiazepine (PBD) dimers are highly potent DNA cross-linking agents used as warheads in Antibody Drug Conjugates (ADCs) for cancer therapy. We propose to investigate the correlation existing between the lipophilicity of those molecules and their activity (both in vitro and in vivo) as well as any effect observed during conjugation. MATERIALS AND METHODS: Reaction progress was monitored by Thin-Layer Chromatography (TLC) using Merck Kieselgel 60 F254 silica gel, with a fluorescent indicator on aluminium plates. Visualisation of TLC was achieved with UV light or iodine vapour unless otherwise stated. Flash chromatography was performed using Merck Kieselgel 60 F254 silica gel. RESULTS: We have successfully designed and synthesized a novel PBD warhead (SG3312) with enhanced physicochemical properties. The warhead also displayed increased potency in vitro. After overcoming some epimerization issues, the synthesis of enantiomerically pure payload was achieved (SG3259) and fulfilled our criteria for a simplified and more efficient conjugation. No addition of propylene glycol was required, and high DAR and excellent monomeric purity were achieved. CONCLUSION: The ADC (Herceptin-maia-SG3259) has been shown to release the active warhead (SG3312) upon exposure to Cathepsin B and demonstrated encouraging activity both in vitro and in vivo.


Assuntos
Antineoplásicos/farmacologia , Benzodiazepinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Benzodiazepinas/síntese química , Benzodiazepinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia em Camada Delgada , Dimerização , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Géis/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Dióxido de Silício/química , Relação Estrutura-Atividade
13.
Macromol Rapid Commun ; 40(10): e1800915, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30924258

RESUMO

Conjugated polymers, especially their second generation with a donor-acceptor alternating structure, have promising properties. These are suitable for two emerging fields, thermoelectrics and bioelectronics, if appropriate structural designs are implemented. This review aims to give a perspective for the potential and challenges of novel conjugated polymers in such applications. In particular, the aspects of synthetic design and the consequences of modifications of the chemical structure on the charge transport in selected second-generation conjugated polymers are reviewed. By understanding the effects of structural motifs on the overall material properties, polymers can be specifically tailored for the respective application. The basics of charge transport measurements are briefly summarized, as the charge transport plays an important role for thermoelectrics as well as for bioelectronics. In particular, the correlation between the reported charge carrier mobility values and the structural design of the polymers is reviewed. Examples of the application of second-generation conducting polymers in thermoelectrics and bioelectronics are shown to demonstrate the current state of research. Finally, the prospect of a purposeful design of new materials for these two emerging fields is discussed.


Assuntos
Polímero Poliacetilênico/química , Polímeros/química , Pirróis/química , Estrutura Molecular , Polímero Poliacetilênico/síntese química , Polímeros/síntese química , Polímeros/classificação , Pirróis/síntese química , Semicondutores
14.
Eur J Med Chem ; 169: 121-143, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30875504

RESUMO

A series of 7H-pyrrolo[2,3-d]pyrimidine derivatives were designed and synthesized as reversible BTK inhibitors, and evaluated their kinase selectivity, anti-proliferation against the B-cell lymphoma cell lines (Ramos, Jeko-1) and cell line BTK enhanced (Daudi) in vitro. Among them, compound 28a exhibited the most excellent potency (IC50 = 3.0 nM against BTK enzyme, 8.52 µM, 11.10 µM and 7.04 µM against Ramos, Jeko-1, Daudi cells, respectively), good kinase selectivity and inhibited BTK Y223 auto-phosphorylation and PLCγ2 Tyr1217 phosphorylation. Importantly, 28a showed efficacy anti-arthritic effect on collagen-induced arthritis (CIA) model in vivo. 28a 60 mg/kg dose level once a day group displayed markedly reduced joint damage and cellular infiltration without any bone and cartilage morphology change.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Desenho de Drogas , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Tirosina Quinase da Agamaglobulinemia/metabolismo , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/metabolismo , Colágeno , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Camundongos Endogâmicos DBA , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirimidinas/síntese química , Pirimidinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
15.
Carbohydr Res ; 475: 48-55, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30825721

RESUMO

Six different types of O-benzyl protected proline derivatives have been synthesized from D-glycals and 2C-formyl-glycals. One of the di-O-benzyl protected proline derivatives has been utilized for the synthesis of polysubstituted pyrrolizidines via [3 + 2] cycloaddition in a stereoselective manner. Further, we also report on the stereoselective synthesis of biologically active 1C-aryl/alkyl pyrrolidines i.e. 4-epi-radicamine B, 4-epi-radicamine A, 1C-butyl and 1C-methyl pyrrolidines through double reductive amination of a variety of D-glucal derived diketones with p-methoxybenzylamine.


Assuntos
Desoxiglucose/análogos & derivados , Prolina/síntese química , Pirróis/síntese química , Desoxiglucose/química , Estrutura Molecular , Prolina/química , Pirróis/química
16.
Colloids Surf B Biointerfaces ; 177: 346-355, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30772669

RESUMO

With an excellent near-infrared (NIR) light-responsive property, polypyrrole (PPy) nanoparticle has emerged as a promising NIR photothermal transducing agent for tumor photothermal therapy (PTT). Herein, we reported the PVP mediated one-pot synthesis of colloidal stable and biocompatible PPy nanoparticles (PPy-PVP NPs) for combined tumor photothermal-chemotherapy. The influence of molecular weight and PVP concentration on the spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency of the resultant PPy-PVP NPs was systematically studied. By choosing PVP with a molecular weight of 360 kDa (concentration of 5 mg/mL) as the template and surface modifier during the synthesis, PPy-PVP NPs with optimal spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency were synthesized. Findings in this study are anticipated to provide an in-depth understanding of the important character of surface engineering in the rational design and biomedical applications of PPy NPs.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Nanopartículas/química , Fototerapia , Polímeros/farmacologia , Pirróis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Coloides/química , Coloides/farmacologia , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Raios Infravermelhos , Camundongos , Camundongos Endogâmicos , Tamanho da Partícula , Polímeros/síntese química , Polímeros/química , Pirróis/síntese química , Pirróis/química , Propriedades de Superfície , Células Tumorais Cultivadas
17.
Chem Asian J ; 14(7): 1059-1065, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30776197

RESUMO

By using a copper-promoted alkyne-azide cycloaddition reaction, two boron dipyrromethene (BODIPY) derivatives bearing a bis(1,2,3-triazole)amino receptor at the meso position were prepared and characterized. For the analogue with two terminal triethylene glycol chains, the fluorescence emission at 509 nm responded selectively toward Hg2+ ions, which greatly increased the fluorescence quantum yield from 0.003 to 0.25 as a result of inhibition of the photoinduced electron transfer (PET) process. By introducing two additional rhodamine moieties at the termini, the resulting conjugate could also detect Hg2+ ions in a highly selective manner. Upon excitation at the BODIPY core, the fluorescence emission of rhodamine at 580 nm was observed and the intensity increased substantially upon addition of Hg2+ ions due to inhibition of the PET process followed by highly efficient fluorescence resonance energy transfer (FRET) from the BODIPY core to the rhodamine moieties. The Hg2+ -responsive fluorescence change of these two probes could be easily seen with the naked eye. The binding stoichiometry between the probes and Hg2+ ions in CH3 CN was determined to be 1:2 by Job's plot analysis and 1 H NMR titration, and the binding constants were found to be (1.2±0.1)×1011 m-2 and (1.3±0.3)×1010 m-2 , respectively. The overall results suggest that these two BODIPY derivatives can serve as highly selective fluorescent probes for Hg2+ ions. The rhodamine derivative makes use of a combined PET-FRET sensing mechanism which can greatly increase the sensitivity of detection.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Mercúrio/análise , Pirróis/química , Triazóis/química , Compostos de Boro/síntese química , Fluorescência , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/síntese química , Limite de Detecção , Pirróis/síntese química , Rodaminas/síntese química , Rodaminas/química , Espectrometria de Fluorescência/métodos , Triazóis/síntese química
18.
J Enzyme Inhib Med Chem ; 34(1): 230-243, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30734610

RESUMO

Two new series of heterocyclic derivatives with potential anticancer activity, in which a pyrrolo[1,2-b]pyridazine or a pyrrolo[2,1-a]phthalazine moiety was introduced in place of the 3'-hydroxy-4'-methoxyphenyl ring of phenstatin have been synthesised and their structure-activity relationship (SAR) was studied. Fourteen of the new compounds were evaluated for their in vitro cytotoxic activity by National Cancer Institute (NCI) against 60 human tumour cell lines panel. The best five compounds in terms of in vitro growth inhibition were screened in the second stage five dose-response studies, three of them showing a very good antiproliferative activity with GI50<100 nM on several cell lines including colon, ovarian, renal, prostate, brain and breast cancer, melanoma and leukemia. Docking experiments on the biologically active compounds showed a good compatibility with the colchicine binding site of tubulin.


Assuntos
Antineoplásicos/farmacologia , Ftalazinas/farmacologia , Piridazinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Ftalazinas/síntese química , Ftalazinas/química , Piridazinas/síntese química , Piridazinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
19.
Molecules ; 24(4)2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-30781470

RESUMO

Following two orthogonal synthetic routes, a series of all four possible A-ring amino derivatives of the natural product Luotonin A (a known Topoisomerase I inhibitor) was synthesized. In both strategies, intramolecular cycloaddition reactions are the key step. The target compounds were obtained in good yields by mild catalytic transfer hydrogenation of the corresponding nitro precursors. In-vitro evaluation of the antiproliferative activity towards human tumor cell lines revealed the 4-amino compound (5b) to be the most effective agent, showing an interesting profile of cytotoxic activity. Among other effects, a significant G2/M cell cycle arrest was observed for this compound, suggesting that either Topoisomerase I is not the only biological target, or that some atypical mechanism is responsible for inhibition of this enzyme.


Assuntos
Alcaloides/síntese química , Alcaloides/farmacologia , Pirróis/síntese química , Pirróis/farmacologia , Quinonas/síntese química , Quinonas/farmacologia , Alcaloides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pirróis/química , Quinonas/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Inibidores da Topoisomerase I/síntese química , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/farmacologia
20.
Chemistry ; 25(14): 3617-3626, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30600841

RESUMO

The synthesis of a conjugate molecule between an unusual red-fluorescent diketopyrrolopyrrole (DPP) unit and a bis-phosphonate (BP) precursor by a click-chemistry strategy to target bone tissue and monitor the interaction is reported. After thorough investigation, conjugation through a triazole unit between a γ-azido rather than a ß-azido BP and an alkyne-functionalized DPP fluorophore group turned out to be the winning strategy. Visualization of the DPP-BP conjugate on osteoclasts and specific antiresorption activity were successfully demonstrated.


Assuntos
Osso e Ossos/diagnóstico por imagem , Difosfonatos/química , Corantes Fluorescentes/química , Cetonas/química , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Pirróis/química , Alquinos/síntese química , Alquinos/química , Animais , Catálise , Bovinos , Química Click , Difosfonatos/síntese química , Corantes Fluorescentes/síntese química , Cetonas/síntese química , Pirróis/síntese química
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