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1.
Org Biomol Chem ; 20(35): 7011-7016, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36000782

RESUMO

Herein, an economical copper-catalyzed reaction of α,ß-unsaturated N-tosylhydrazones with diaryliodonium salts to construct both N-arylpyrazoles and diaryl sulfones has been developed. Both the p-toluenesulfonyl anion and the 3-arylpyrazole intermediates were formed in situ from N-tosylhydrazones. Subsequently, the former reacted rapidly with diaryliodonium salts to give diaryl sulfones and aryl iodide intermediates, and the latter reacted with aryl iodide to give N-arylpyrazoles under copper-catalyzed conditions. Using unsymmetrical mesityl phenyliodonium salts as substrates, mesityl p-toluenesulfide was obtained as the major product. This reaction took full advantage of the "waste" part of substrates to form an extra diaryl sulfone.


Assuntos
Cobre , Sais , Catálise , Iodetos , Sulfonas
2.
Neoplasma ; 69(5): 1019-1028, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35900318

RESUMO

Systematic treatments including chemotherapy, endocrine therapy, and HER2-targeted therapy are important therapeutic approaches to breast cancer. However, drug resistance is a major barrier to achieving a cure in breast cancer (BC) patients. Hence, it is urgent to gain insight into the drug-resistance mechanisms in order to improve the prognosis of BC patients. Genetic alternations, epigenetic alternations, and other non-genetic mechanisms such as BC stem-like cells, metabolic reprogramming, and tumor microenvironment contribute to drug resistance of BC. With the development of single-cell sequencing of circulating tumor cell and next-generation sequencing of matched pre- and post- progression tumor biopsies or ctDNA from BC patients with drug resistance, new mechanisms of resistance are being discovered. An increasing number of microRNAs and long non-coding RNAs have been found to be associated with the drug resistance of BC. However, there are few reports on the role of circular RNAs (circRNAs) as master regulators of drug resistance. Therefore, there is still much to say in the field of drug resistance-related circRNAs. In this review, we mainly focus on literature evidence for the detailed mechanisms associated with systematic treatments' resistance of BC and how circRNAs intensify or weaken drug resistance. Exogenous expression of tumor suppressive circRNAs or knockdown of oncogenic circRNAs has been verified to reverse drug resistance of BC cells, which highlights that circRNAs may function as potential biomarkers and/or therapeutic targets of BC. Treatment targeting abnormally expressed circRNAs alone or combined with other systemic treatments may be a promising approach to conquering drug resistance.


Assuntos
Neoplasias da Mama , MicroRNAs , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , MicroRNAs/genética , Prognóstico , RNA Circular/genética , Microambiente Tumoral
3.
Chemistry ; 27(13): 4312-4316, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326645

RESUMO

Herein, a [3+2] cycloaddition of aza-oxyallylic cations with ethynylbenziodoxolones for synthesis of new λ3 -iodanes containing spirocyclic 4-oxazolidinone has been developed. This cyclic λ3 -iodanes display stability in air and excellent solubility in organic solvent. Using them as substrate, both the 4,1-benzoxazepine-2,5-diones and symmetrical 1,3-diynes derivatives were afforded in high yield under copper(I)-catalyzed conditions.

4.
Org Biomol Chem ; 17(37): 8561-8570, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31513227

RESUMO

An efficient method for the synthesis of N-sec-alkylpyrazoles through a base-promoted cascade cyclization/Michael addition reaction of α,ß-unsaturated N-tosylhydrazones with ortho-hydroxybenzyl alcohols has been developed. The desired products containing di- or triaryl groups at the same carbon atom were afforded in good to excellent yields with excellent regioselectivities (>20 : 1). Moreover, a three-component reaction of ortho-hydroxybenzyl alcohols, α,ß-unsaturated N-tosylhydrazones and saturated N-tosylhydrazones also took place to afford pyrazoles in good yields. This reaction offers a new route to triarylmethanes with a simple operation and is applicable for large-scale synthesis.

5.
J Chem Ecol ; 43(3): 236-242, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28251439

RESUMO

Holotrichia parallela (Coleoptera: Scarabaeoidea) is a notorious pest of many crops. To improve the effectiveness of its female-produced sex pheromone (L-isoleucine methyl ester:(R)-(-)-linalool = 6:1), 14 plant volatiles, including dodecanoic acid, dodecanal, farnesol, α-farnesene, (Z)-3-hexen-1-ol, (E)-2-hexen-1-ol, (Z)-3-hexenyl acetate, (E)-2-hexenyl acetate, (R)-(+)-limonene, α-phellandrene, α-pinene, ocimene, methyl benzoate, and benzaldehyde, were individually evaluated using electroantennography and olfactometer assays. (E)-2-Hexenyl acetate and (Z)-3-hexenyl acetate were found to elicit the strongest responses in both males and females. Further testing of these two compounds in mixtures with the sex pheromone indicated that (E)-2-hexenyl acetate had a stronger synergistic effect than (Z)-3-hexenyl acetate. Field evaluations showed that mixtures of (E)-2-hexenyl acetate and the sex pheromone resulted in significantly higher catches than the sex pheromone alone. Using a 5:1 mixture of the sex pheromone and (E)-2-hexenyl acetate, the maximum number of females per trap per day was 14, showing a synergistic effect of a factor of four. For males, a 3:1 mixture of the sex pheromone and (E)-2-hexenyl acetate yielded a maximum number of 310 individuals per trap per day, equivalent to a synergistic effect of 175%. These results may provide the basis for the development of efficient pest management systems against H. parallela using plant volatiles and insect sex pheromones.


Assuntos
Besouros/química , Besouros/efeitos dos fármacos , Plantas/química , Atrativos Sexuais/farmacologia , Compostos Orgânicos Voláteis/farmacologia , Animais , Sinergismo Farmacológico , Feminino , Masculino , Controle Biológico de Vetores , Olfato/efeitos dos fármacos , Compostos Orgânicos Voláteis/química
6.
Yao Xue Xue Bao ; 51(4): 507-16, 2016 04.
Artigo em Zh | MEDLINE | ID: mdl-29859518

RESUMO

Hydrogen sulfide (H(2)S) is considered as a new member of gasotransmitter family, following nitric oxide (NO) and carbon monoxide (CO). H2S exerts important biological effects in mammals, which has drawn more and more attention in recent years. It is proved that H(2)S has a role in the regulation of physiological and pathophysiological processes in the cardiovascular system and the nervous system. Several cardiovascular and nervous diseases are connected to H(2)S. H(2)S-releasing agents (also known as H(2)S donors) have been widely used not only as useful research tools but also potential therapeutic agents. In this review, we provide an overview of the chemistry and biology of H(2)S, and summarize the chemistry and biological activity of some natural and synthetic H(2)S donors. We introduce the developments of currently available H(2)S-releasing drugs including H(2)S-non-steroidal anti-inflammatory drugs, H(2)S-nervous system drugs and NO-H(2)S-releasing drugs. We hope this review will be a value reference in the development of H(2)S-releasing drugs in the treatment of cardiovascular and nervous diseases.


Assuntos
Anti-Inflamatórios não Esteroides/química , Fármacos do Sistema Nervoso Central/química , Sulfeto de Hidrogênio/química , Animais , Doenças Cardiovasculares , Doenças do Sistema Nervoso
7.
Arch Insect Biochem Physiol ; 87(4): 177-200, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25099623

RESUMO

The dark black chafer, Holotrichia parallela, is an economically important pest in China and worldwide. Traps based on chemical communication are being developed as an alternative control measure to pesticides for this pest, and studies to reveal chemical communication mechanisms in this pest are highly desirable. To systematically analyze genes potentially involved in chemical communication in this pest, we generated a comprehensive transcriptome with combined samples derived from multiple tissues and developmental stages. A total of 43,967 nonredundant sequences (unigenes) with average length of 806 bp were obtained. These unigenes were annotated into different pathways using gene ontology analysis and cluster analysis of orthologous groups of proteins, and kyoto encyclopedia of genes and genomes. In total, 25 transcripts encoding odorant-binding proteins (OBPs) and 16 transcripts encoding chemosensory proteins (CSPs) were identified based on homology searches. Tissue-specific expression profile indicates that OBP17 and CSP7 are likely responsible for male sex pheromone recognition, whereas OBP1-4, OBP9, OBP13-14, OBP17-18, OBP20, OBP22, OBP25, CSP1-7, CSP11, and CSP12-15 are likely responsible for chemical communication between the beetle and environments. Our data shall provide a foundation for further research on the molecular aspects of chemical communication of this insect, and for comparative genomic studies with other species.


Assuntos
Besouros/genética , Feromônios/genética , Receptores Odorantes/genética , Receptores de Feromônios/genética , Transcriptoma , Sequência de Aminoácidos , Comunicação Animal , Animais , Sequência de Bases , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/genética , Masculino , Receptores Odorantes/química
8.
Yi Chuan ; 35(3): 255-61, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23575531

RESUMO

The mammalian SWI/SNF complex is one of ATP-dependent chromatin-remodeling complexes, which plays important roles in cell proliferation, differentiation, development and tumor suppression. ARID1A (AT-rich interactive domain-containing protein 1A) is a large subunit of SWI/SNF complex, and also an ARID family member with non- sequence-specific DNA binding activity. ARID1A is a tumor suppressor gene which is frequently mutated in many cancers, such as ovarian, bladder and gastric cancers. ARID1A can suppress cell proliferation through the up-regulation of p21 and the down-regulation of E2F-responsive genes. These findings on ARID1A and its role of tumor suppression contribute to understanding the mechanism of cancer development and developing new therapy for cancer.It is introduced in the review that ARID1A basic characteristic, related to cancer development, and biological role for full understanding of ARID1A.


Assuntos
Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Proteínas de Ligação a DNA , Humanos , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética
9.
Bioorg Med Chem Lett ; 22(24): 7688-92, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23102889

RESUMO

New quinolone derivatives bearing a cis- or trans-cyclohexane side chain at the C-7 position have been synthesized and evaluated for their antibacterial activities against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using the agar dilution method. The activities of compound 53 against these three bacteria were superior to those of the reference drug lomefloxacin. Compounds bearing a cis-cyclohexane side chain generally exhibited greater antibacterial activity than their corresponding trans-isomers.


Assuntos
Antibacterianos/farmacologia , Cicloexanos/química , Escherichia coli/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Fluoroquinolonas/síntese química , Fluoroquinolonas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o574, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412491

RESUMO

In title compound, C(16)H(9)ClO(4), the coumarin ring system is approximately planar [maximum deviation = 0.056 (1) Å] and is oriented with respect to the benzene ring at an angle of 22.60 (7)°. Inter-molecular C-H⋯O hydrogen bonding is present in the crystal.

11.
Yi Chuan ; 34(11): 1501-4, 2012 Nov.
Artigo em Zh | MEDLINE | ID: mdl-23208148

RESUMO

Susumu Tonegawa is a Japanese molecular biologist who won the Nobel Prize for Physiology or Medicine in 1987 for his discovery of "the genetic principle for generation of antibody diversity". Susumu Tonegawa is also famous for his important contributions on neuroscience, who explored the molecular and cellular mechanisms underlying learning and memory. In this article, the life and research on Susumu Tonegawa was introduced.


Assuntos
Anticorpos/genética , Diversidade de Anticorpos , Anticorpos/imunologia , História do Século XX , História do Século XXI , Japão , Prêmio Nobel
12.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): o3363, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22199857

RESUMO

The asymmetric unit of the title compound, C(12)H(16)BrNO(3)S, contains two independent mol-ecules. In each mol-ecule, the azetidine four-membered ring adopts a nearly planar conformation, the maximum deviations being 0.087 (3) and 0.079 (3) Å. The mean azetidine plane is twisted by 75.2 (2) and 73.6 (2)° with respect to the plane of the benzene ring in the two independent mol-ecules. The crystal packing is stabilized by O-H⋯O hydrogen bonds.

13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): o439, 2011 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-21523103

RESUMO

THE TITLE COMPOUND [SYSTEMATIC NAME: 6ß,10-dihy-droxy-1α,14α,16ß-trimeth-oxy-4-methyl-7ß,8-(methyl-enedi-oxy)-20-ethyl-aconitan-6-yl acetate], C(27)H(41)NO(8), is a C(19)-diterpenoid alkaloid and a major diterpenoid alkaloid component of the roots of Delphinium delavayi Franch. var. pogonanthum (Hand.-Mazz.) W. T. Wang. The mol-ecule has a lycoctonine carbon-atom skeleton with four six-membered rings and three five-membered rings among; three of the six-membered rings adopt chair conformations with the fourth adopting a boat conformation while all of the five-membered rings exhibit envelope conformations. Inter-molecular O-H⋯O hydrogen bonding is present in the crystal structure.

14.
Yi Chuan ; 33(2): 117-22, 2011 Feb.
Artigo em Zh | MEDLINE | ID: mdl-21377967

RESUMO

The gene fusions between transmembrane protease serine 2 (TMPRSS2) and E26 (ETS) transcription factors are present in over 50% of patients with prostate cancer. TMPRSS2-ERG is the most common gene fusion type. The ERG overexpression induced by TMPRSS2-ERG gene fusion contributes to the development of prostate cancer. Both androgen receptor binding and genotoxic stress induce chromosomal proximity and TMPRSS2-ETS gene fusions. TMPRSS2-ERG gene fusion functions as a biomarker for prostate cancer, which can be easily detected in urine. This review focuses on the characteristics, oncogenic and rearranged mechanism, and clinical application of TMPRSS2-ETS gene fusions.


Assuntos
Fusão Gênica , Neoplasias da Próstata/genética , Proteína Proto-Oncogênica c-ets-1/genética , Serina Endopeptidases/genética , Humanos , Masculino , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Serina Endopeptidases/metabolismo , Transativadores/genética , Transativadores/metabolismo , Regulador Transcricional ERG
15.
Yi Chuan ; 32(4): 295-300, 2010 Apr.
Artigo em Zh | MEDLINE | ID: mdl-20423883

RESUMO

Fetal hemoglobin (HbF) is the main type of hemoglobin in the fetus and few in adult, but retains high levels in some people and patients with beta-thalassemia major or sickle cell disease. High HbF levels are beneficial to ameliorating the disease severity of the anemia. Previous researches had established that quantitative trait loci were associated with 6q23 and 2p15. Recent researches indicated that HBS1L-MYB in 6q23 and BCL11A in 2p15 are highly correlated to HbF levels. These discoveries not only help to understanding of mechanism in HbF expression, but also provide potential drug targets for therapy of sickle cell disease. The progress on genes related to fetal hemoglobin quantitative trait and potential applications was summarized in this review.


Assuntos
Hemoglobina Fetal/genética , Locos de Características Quantitativas/genética , Proteínas de Transporte/genética , Regulação da Expressão Gênica , Genes myb/genética , Humanos , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras
16.
Chem Pharm Bull (Tokyo) ; 57(9): 1000-3, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19721265

RESUMO

Two new triterpenoid saponins, brachyposide A (1) {3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl-2beta,3beta,16alpha,23-tetrahydroxyolean-12-en-28-oic acid 28-O-beta-D-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl ester} and brachyposide B (2) {3-O-beta-D-glucopyranosyl-(1-->3)-beta-D-galactopyranosyl-(1-->3)-beta-D-glucuronopyranosyl-2beta,3beta,23-trihydroxyolean-12-en-28-oic acid 28-O-beta-D-xylopyranosyl-(1-->4)-[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester}, together with four known triterpenoid saponins, including tabguticoside A, nipponoside D, palmatoside E and ciwujianoside A(1), were isolated from the stem bark of Acanthopanax brachypus. Their structures were elucidated on the basis of spectroscopic and chemical evidence.


Assuntos
Eleutherococcus/química , Saponinas/química , Triterpenos/química , Espectroscopia de Ressonância Magnética , Caules de Planta/química , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação
17.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): o1408, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-21583251

RESUMO

The title compound, C(11)H(19)NO(6), is an important inter-mediate for the synthesis of cephalosporin derivatives. The N atom is in a planar configuration. In the crystal, mol-ecules are linked into zigzag layers parallel to (100) by O-H⋯O hydrogen bonds.

18.
Zhong Yao Cai ; 32(2): 173-6, 2009 Feb.
Artigo em Zh | MEDLINE | ID: mdl-19504955

RESUMO

OBJECTIVE: To investigate the influential factors and establish culture method for G. uralensis callus. METHODS: To study the possible effective factors of culture condition by comparing with different explants, light, plant hormones and its ratio. RESULTS: The hypocotyl was the best among different explants, its inducing ratios was 94%, and the callus occurred earliest. When the calluses were inoculated on MS + 6 - BA (1.0-2.0) mg/L + NAA (0.5-1.0) mg/L, adventitious buds formed. 2,4-D could induce non-embryogenic callus, the compounding proportions of 6 - BA and NAA could induce embryogenic callus. Light influenced induction and growth of callus. CONCLUSION: Different explants, components of hormone and light are the influencial factors of callus induction and growth of G. uralensis.


Assuntos
Glycyrrhiza uralensis/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/farmacologia , Plantas Medicinais/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/métodos , Ácido 2,4-Diclorofenoxiacético/farmacologia , Meios de Cultura , Glycyrrhiza uralensis/classificação , Glycyrrhiza uralensis/efeitos dos fármacos , Hipocótilo/efeitos dos fármacos , Hipocótilo/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Plantas Medicinais/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Luz Solar
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