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1.
Org Biomol Chem ; 14(47): 11176-11182, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27834972

RESUMO

The facile tuning of the fluorescent properties of organogels is highly desirable for optical switches, light-emitting diodes, chemosensors and bioprobes. The design of organic molecules with multiple emission colors but only one molecular platform remains challenging. Herein, a new cholesterol-based organogelator N1 containing D-A pairs (salicylaldehyde and naphthalimide units) was designed. We successfully obtained multiple solvent-tuned emission colors in both the solution and gel states using a unimolecular platform. Moreover, the effects of the solvent on the gel morphology, rheology and anion-responsive properties were studied. Finally, we showed that the gel in benzene displayed reversible thermochromic properties with changes in emission color from yellow-green to red. Several experiments suggested that a short-distance and ordered array of the D-A pairs facilitated the efficient intermolecular electron transfer of the fluorophores.

2.
Bioorg Med Chem ; 24(21): 5197-5205, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27594550

RESUMO

A series of arylidene N-alkoxydiketopiperazines was designed and stereoselectively synthesized via oxime-ether formation and intramolecular acylation. Possible cyclization and acid-catalyzed rearrangement-fragmentation mechanisms were discussed. The crystal structure of the novel diketopiperazine further confirmed the rearrangement mechanism. Most compounds exhibited antitumor activity. Several compounds were more potent against caspase-3. Specifically, compounds 6e, 6g, and 6f inhibited caspase-3 at IC50 values lying within the low micromolar range and demonstrated good selectivity. The binding modes of alkoxydiketopiperazines in the active center of caspase-3 were also discussed based on the molecular docking results.


Assuntos
Antineoplásicos/farmacologia , Caspase 3/metabolismo , Dicetopiperazinas/farmacologia , Inibidores Enzimáticos/farmacologia , Peptídeos Cíclicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Dicetopiperazinas/síntese química , Dicetopiperazinas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Relação Estrutura-Atividade
3.
Bioorg Med Chem ; 23(10): 2562-7, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25865131

RESUMO

A series of open-chain analogs of cyclic peptides was designed and synthesized using sansalvamide A as a model compound. All compounds exhibited low antitumor activity. Furthermore, the evaluation of their inhibitory potency toward IMPDH, SHP2, ACHE, proteasome, MAGL, and cathepsin B showed that all of the compounds were potent against protein tyrosine phosphatase Shp2. Specifically, compounds 1a, 1d, 2b, and 2f were found to inhibit SHP2 with IC50 values in the low micromolar range and good selectivity. Based on the molecular docking results, the binding modes of the chain cyclic peptides in the active center of SHP2 were discussed.


Assuntos
Inibidores Enzimáticos/síntese química , Peptídeos Cíclicos/síntese química , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Acetilcolinesterase/química , Domínio Catalítico , Catepsina B/antagonistas & inibidores , Catepsina B/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios Enzimáticos , Inibidores Enzimáticos/farmacologia , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/química , Expressão Gênica , Células HeLa , Humanos , IMP Desidrogenase/antagonistas & inibidores , IMP Desidrogenase/química , Cinética , Simulação de Acoplamento Molecular , Peptídeos Cíclicos/farmacologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Relação Estrutura-Atividade
4.
Infect Drug Resist ; 17: 1971-1978, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779351

RESUMO

Background: Mucormycosis is a fatal invasive fungal infection that commonly affects immunocompromised children. The aim of our study was to investigate the clinical manifestations, treatments, and prognosis of pediatric patients with mucormycosis. Methods: We conducted a retrospective search in Shenzhen Children's Hospital from July 2013 to July 2023 for all patients with mucormycosis. The clinical manifestation, pathogen detection, radiology, treatments, and prognosis were analyzed. Results: Four cases were identified. Underlying conditions included acute myeloid leukemia with myeloid sarcoma (n = 1), thalassemia (post-allogeneic hematopoietic stem cell transplantation; n = 1), systemic lupus erythematosus (n = 1), and bilateral nephroblastoma (post-bilateral nephrectomy; n = 1). Two patients were disseminated mucormycosis, one case was pulmonary mucormycosis, and one case was cerebral mucormycosis. Fever, cough, and dyspnea were the main clinical symptoms of pulmonary mucormycosis, headache was the main clinical symptom of cerebral mucormycosis. Lung CT findings included consolidation, multiple nodules, halo sign, air crescent sign, and pleural effusion. The contrast-enhanced CT showed pulmonary artery and pulmonary vein occlusions in two patients and pseudoaneurysm in two patients. Amphotericin B formulations were administered as first-line therapy in all cases; in three cases, Triazole was administered in combination with amphotericin B. Conclusion: Mucormycosis is a life-threatening disease involving multiple systems. Aorta pseudoaneurysm is a rare and fatal complication, enhanced CT can assist in diagnosis. Early diagnosis and appropriate therapeutic strategies are needed.

5.
Org Biomol Chem ; 10(3): 663-70, 2012 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-22101975

RESUMO

Amorphous nickel powder (Ni(0)) was utilised as a catalyst under mild, aqueous, basic conditions for enhancing the sodium borohydride-mediated reduction of C-N multiple bonds such as oximes, imines, hydrazones and nitriles to produce the corresponding amines in good to excellent yields.


Assuntos
Boroidretos/química , Carbono/química , Níquel/química , Nitrogênio/química , Catálise , Oxirredução , Especificidade por Substrato
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): o1516, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590383

RESUMO

In the title compound, C(10)H(14)NO(4) (+)·Cl(-), the benzene ring makes a dihedral angle of 64.68 (4)° with the methyl-amino-propano-ate unit, which is bonded to the catechol ring via a methyl-ene C atom. A strong intra-molecular O-H⋯O hydrogen bond occurs. In the crystal, O-H⋯O, N-H⋯Cl and O-H⋯Cl hydrogen bonds and weak C-H⋯O inter-actions link the mol-ecules into a three-dimensional network.

7.
Org Biomol Chem ; 9(21): 7476-81, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-21918789

RESUMO

A stereoselective synthesis of arylidene N-alkoxydiketopiperazines via oxime-ether formation and intramolecular acylation is described, followed by an acid-catalysed rearrangement-fragmentation to give novel diketopiperazine hemiaminal derivatives with useful bioactivity against certain tumour cell lines.


Assuntos
Dicetopiperazinas/química , Dicetopiperazinas/síntese química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1482, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754851

RESUMO

In the title compound, C(22)H(20)N(+)·Cl(-), the anthracene system makes a dihedral angle of 72.65 (4)° with the benzene ring. The C-N-C-C torsion angles in the chain connecting the benzene ring and anthracene system are 52.24 (15) and -170.73 (11)°. The crystal structure is stabilized by inter-molecular N-H⋯Cl and C-H⋯Cl hydrogen bonds, which link the mol-ecules into tetra-mers about inversion centers.

9.
Org Lett ; 23(23): 9094-9099, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34780200

RESUMO

Iron-catalyzed direct SN2' dehydroxyboration of allylic alcohols has been developed to access (E)-stereoselective allylboronates. Allylic alcohols with diverse structures and functional groups, especially derived from natural products, underwent smooth transformation. The six-membered ring transition state formed by allylic alcohols and iron-boron intermediate was indicated to be the key component involved in transfer of the boron group, activation of the C-OH bond, and control of the stereoselectivity.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1384, 2010 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21579465

RESUMO

In the title compound, C(15)H(20)O(7), the benzene ring makes dihedral angles of 69.17 (5) and 80.81 (4)° with the two side chains of malonate. The two malonate side chains comprising C/C/O/C atoms are oriented at right angles [86.26 (6)°] with respect to each other. In the crystal structure, the crystal packing is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds, which link the mol-ecules into an infinite network.

11.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1383, 2010 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21579464

RESUMO

In the title compound, C(15)H(15)NO(4), the quinoline ring system and one of the malonate side chains are essentially coplanar (r.m.s. deviation = 0.0297 Å). The two malonate C-C(=O)-O-CH(3) side chains are oriented at right angles [89.68 (8)°] with respect to each other. The crystal packing is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds, which link the mol-ecules into dimers about inversion centers.

12.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1792, 2009 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21583498

RESUMO

In the title compound, C(25)H(23)N(3)O(5)S, the central 1,3,4-oxadiazole ring makes dihedral angles of 35.05 (7), 23.68 (7) and 82.55 (8)°, with the three benzene rings. In the crystal structure, the packing is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds, which link the mol-ecules into an infinite network.

13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o2010, 2009 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21583681

RESUMO

In the title compound, C(20)H(22)N(2)O(5), the central 1,3,4-oxadiazole ring is essentially planar [r.m.s. deviation from the best plane of 0.0011 Å] and makes dihedral angles of 4.10 (3) and 13.32 (4)° with the two benzene rings. In the crystal structure, the packing is stabilized by weak non-classical inter-molecular C-H⋯N hydrogen bonds, which link the mol-ecules into an extended network.

14.
Clin Cancer Res ; 25(6): 1989-2000, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30463848

RESUMO

PURPOSE: Our study aimed to investigate whether CAF (cancer-associated fibroblasts) were involved in long noncoding RNAs (lncRNA)-regulated radioresponse in esophageal squamous cell carcinoma (ESCC).Experimental Design: By use of lncRNAs PCR array, 38 lncRNAs were screened in esophageal cancer cells and in normal esophageal epithelial cells Het-1A. LncRNA DNM3OS was detected in tumor tissues of patients with ESCC and in matched normal esophageal epithelial tissues by qRT-PCR analysis and in situ hybridization assay. The association of DNM3OS and tumor radioresistance was investigated in vitro and in vivo. The influences of DNM3OS on DNA damage response (DDR) was investigated by Western blotting, immunofluorescence imaging, and comet assay. The mechanisms by which CAFs promoted DNM3OS expression was investigated by kinase inhibitors' screening, luciferase assay, and chromatin immunoprecipitation. RESULTS: Among the 38 lncRNAs tested, DNM3OS was found to have a much higher expression level in esophageal cancer cells than in Het-1A. In tumor tissues of 16 patients with ESCC, the expression level of DNM3OS showed an average increase of 6.3429-fold compared with that in matched normal tissues. DNM3OS conferred significant radioresistance in vitro and in vivo by regulating DDR. CAFs promoted the expression of DNM3OS with a 39.2554-fold and 38.3163-fold increase in KYSE-30 and KYSE-140, respectively. CAFs promoted the expression of DNM3OS in a PDGFß/PDGFRß/FOXO1 signaling pathway-dependent manner. FOXO1, a transcription factor downstream of PDGFß/PDGFRß signaling pathway, initiated the transcription of DNM3OS by binding to DNM3OS promoter. CONCLUSIONS: Our study highlighted CAF-promoted DNM3OS as an attractive target to reverse tumor radioresistance in ESCC.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/radioterapia , Proteína Forkhead Box O1/metabolismo , RNA Longo não Codificante/genética , Tolerância a Radiação/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Proliferação de Células , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos da radiação , Dinamina III/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Esôfago/patologia , Esôfago/efeitos da radiação , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 11): o2170, 2008 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21581030

RESUMO

In the title compound, C(20)H(15)ClN(4)O(7)S·4CH(3)COOH, the central o-vanillin group makes dihedral angles of 9.50 (11) and 42.86 (7)°, respectively, with its attached pyridine and nitro-benzene rings. The crystal packing is stabilized by N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds and C-H⋯O inter-actions, leading to an infinite three-dimensional network. A short intramolecular C-H⋯O contact is also seen.

16.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 11): o2244, 2008 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21581098

RESUMO

In the title compound, C(24)H(20)BrN(3)O(4)S, the central benzene ring makes dihedral angles of 17.13 (13), 39.83 (13) and 58.37 (13)°, respectively, with the pyrazolone ring, the bromo-benzene ring and the terminal phenyl ring. In the crystal structure, the packing is stabilized by a weak non-classical inter-molecular C-H⋯O hydrogen bond which links the mol-ecules into a chain propagating in [100].

17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 11): o2245, 2008 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21581099

RESUMO

In the title compound, C(25)H(22)N(4)O(4), the central benzene ring, makes dihedral angles of 74.35 (6), 17.01 (8) and 62.19 (7)°, respectively, with the nitro-benzyl ring, the pyrazolone ring and the terminal phenyl ring. Inter-molecular C-H⋯O hydrogen bonds help to consolidate the crystal packing.

18.
Biomed Res Int ; 2018: 3928915, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30426007

RESUMO

UHMWPE granule could induce macrophages and inflammatory responses in interfacial tissues, which eliminated the wear debris of UHMWPE component and further induced dissolution of the surrounding bone, leading aseptic loosening. However, the mechanism of synovial cells, especially fibroblast-like synovial (FLS) cells response to UHMWPE, remains unknown. Herein we choose FLS cells as research object. Vimentin (+) CD68 (-) was identified by flow cytometry and immunofluorescent staining assay, and the cells were identified as FLS cells, which was consistent with the experimental requirements. The inhibitory evaluation showed that UHMWPE could significantly promote the proliferation and inhibit apoptosis of FLS cells in dose- and time-dependent manners and increase the levels of proinflammatory cytokines, including IL-6, IL-1ß, TNF-α, PGE2, MMP2, and LOX. UHMWPE also can induce the expression of mIL-6R protein in FLS cells and further investigate the relationship between apoptosis and inflammation. Interestingly enough, when we added the interleukin-6 receptor antagonist (IL-6RA), the expression levels of proapoptosis-related proteins increased; in other words, UHMWPE-induced antiapoptosis diminished by IL-6RA (50 µg/ml). Taken together, these findings clearly demonstrated that UHMWPE promote growth in FLS cells through upregulating inflammatory factors to produce antiapoptotic effect.


Assuntos
Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Polietilenos/farmacologia , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/metabolismo , Membrana Sinovial/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Polietilenos/efeitos adversos , Membrana Sinovial/patologia
19.
ACS Appl Mater Interfaces ; 9(15): 13666-13675, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28353330

RESUMO

In this study, we show that a novel kind of cholesterol-based gelator NPS containing pyridyl and naphthalimide units can visually discriminate cyclohexane/cyclopentane from hexane/pentane on the basis of distinct optical differences in the gel platform, which is not observed in solution. The effect of congeneric solvents on the gel properties, such as morphology, rheology, and stimuli-responsive properties, is also studied. Intriguingly, NPS can form self-supporting, self-healing, fluorescent, and highly visible transmittance gels in cyclohexane that can selectively and visually respond to picric acid. It is deduced that NPS adopted H-type aggregation mode in cyclohexane, and the gel exhibits a strong green emission, whereas, in hexane, J-type aggregates of NPS molecules are observed with yellow emission. Correlations between the gelation properties and Hansen solubility parameters indicate that the dispersion interactions are the main factor for the selective gelation of NPS toward short-chain alkanes. A comparison of Hansen solvent parameters indicated that a similar energetic weight of the hydrogen-bonding units is the major contribution for the strong and specific interaction between NPS and cyclohexane. Furthermore, we demonstrated that the NPS xerogel can selectively solidify cyclohexane in the single-phase liquid of solvent mixtures, exhibiting fast gelation, high separation efficiency (>92%), and easy recycling of gelator and liquids. To the best of our knowledge, herein, we report the first paradigm that molecular gel formation is developed to visually discriminate and separate organic analogues of solvents with similar polarity.

20.
Springerplus ; 5: 400, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27047726

RESUMO

Most of polypeptides containing α,ß-dehydroamino acids have important biological activity, so exploration of synthetic method has practical significance. In this paper, dipeptides were prepared from l-threonine by protecting of c-terminal allyl acetate, and condensing reaction with a series of N-Boc amino acid. Then, treatment of dipeptides obtained with DMAP, (Boc)2O and tetramethylguanidine in the acetonitrile occured ß-elimination reaction to yield stereoselectively dehydrodipeptides. Structures of dehydrodipeptides were confirmed by (1)H NMR, (13)C NMR and MS. Analysis of (1)H NMR, 2D NMR and crystal structure showed that the dehydrodipeptides were Z-configuration.Graphical abstractDehydrodipeptides were prepared from l-threonine. Their structures were confirmed by (1)H NMR, (13)C NMR and MS.

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