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1.
Bioorg Med Chem ; 99: 117606, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38262304

RESUMO

Multidrug and toxin extrusion (MATE) inhibitors improve the antimicrobial susceptibility of drug-resistant bacteria by preventing the efflux of administered antibiotics. In this study, we optimized the chemical structure of a previously identified bacterial-selective MATE inhibitor 1 (EC50 > 30 µM) to improve its activity further. Compound 1 was divided into three fragments (aromatic part, linker part, and guanidine part), and each part was individually optimized. Compound 31 (EC50 = 1.8 µM), a novel pentafluorosulfanyl-containing molecule synthesized following optimized parts, showed antimicrobial activity against MATE-expressing strains at concentrations lower than conventional inhibitor 1 when co-administrated with norfloxacin. Furthermore, 31 was not cytotoxic at effective concentrations. This suggests that compound 31 can be a promising candidate for combating bacterial infections, particularly those resistant to conventional antibiotics by MATE expression.


Assuntos
Antibacterianos , Proteínas de Membrana Transportadoras , Proteínas de Membrana Transportadoras/metabolismo , Antibacterianos/farmacologia , Norfloxacino/farmacologia , Transporte Biológico , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo
2.
Beilstein J Org Chem ; 20: 1341-1347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887571

RESUMO

A novel Rh-catalyzed one-pot homo-coupling reaction of aryl Grignard reagents was achieved. The reaction with bromobenzenes having an electron-donating group or a halogen substituent gave the corresponding homo-coupling products in good yields, although the reaction using heterocyclic or aliphatic bromides scarcely proceeded. A Rh(III)-bis(aryl) complex, which might be formed from RhCl(PPh3)3 and the aryl Grignard reagents, plays an important role in giving the homo-coupling products in this reaction. Furthermore, we applied the reaction to the synthesis of a novel inhibitor for integrins which is critical for several diseases.

3.
Chem Rec ; 23(9): e202300029, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37017496

RESUMO

In recent years, hydrofluorocarbon compounds such as chlorofluorocarbons, hydrochlorofluorocarbons, and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) have been used as fluorine-containing building blocks to construct functional fluorine-containing compounds, e. g., polymers, liquid crystals, and medicines. Hydrofluorocarbons promote the formation of reactive fluoroalkyl or fluoroalkenyl species via anionic or radical processes, and these species can act as nucleophiles or electrophiles depending on the reaction conditions. Progress in fluorine chemistry using hydrofluorocarbons in the last 30 years is described in this review and diverse reactions are discussed, including the fluoroalkyl/alkenyl products and proposed mechanisms involved.

4.
Exp Aging Res ; : 1-17, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37942547

RESUMO

The ability to predict collisions with moving objects deteriorates with aging. We followed the affordance-based model to identify optical variables that older adults had difficulty using for collision prediction. We reproduced a modified version of the interception task used in Steinmetz (Steinmetz, Layton, Powell, & Fajen, 2020, "Affordance-based versus current - future accounts of choosing whether to pursue or abandon the chase of a moving target," Journal of Vision, 20(3), 8) in a virtual reality (VR) environment and newly introduced perturbation for each of three optical variables (vertical and horizontal expansions of a moving object and the bearing angle produced between participants and a moving object). We expected that perturbation would negatively affect the performance only for those who rely on the optical variable to perform the interception task effectively. We tested 18 older and 15 younger adults and showed that older participants were not negatively affected by the perturbation for the vertical and horizontal expansion of a moving object, while they showed decreased performance when the perturbation was introduced with a bearing angle. These findings suggest that predicting collisions with moving objects deteriorates with aging because the perception of object expansion is impaired with aging.

5.
Bioorg Med Chem Lett ; 72: 128868, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35764276

RESUMO

Although cytochrome P450 3A4 (CYP3A4) inhibitors are used as boosters to increase drug absorption, the inhibition of CYP3A4 activity may affect the metabolism of other co-administered drugs. Therefore, we screened for and developed a new class of boosters to improve the oral availability of drugs. We identified benzyloxyphenyl imidazole and phenethylphenyl imidazole derivatives as new types of CYP3A4 inhibitors. Among the compounds synthesized, an ester 5c was found to inhibit CYP activity and the compound 5c was gradually converted to an inactive metabolite 5d under physiological conditions, indicating that the ester 5c may represent a novel ante-drug type booster.


Assuntos
Inibidores do Citocromo P-450 CYP3A , Nitroimidazóis , Inibidores de 14-alfa Desmetilase , Antifúngicos , Inibidores do Citocromo P-450 CYP2C9 , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacologia , Ésteres , Imidazóis/farmacologia
6.
Bioorg Med Chem ; 74: 117042, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36215813

RESUMO

Drug efflux pump inhibitors for the multidrug resistance protein HmrM, a member of the multidrug and toxin extrusion (MATE) family of transporters, were investigated to increase the drug susceptibility of multidrug-resistant bacteria and restore the antimicrobial effect of fluoroquinolones, such as norfloxacin. The lead inhibitor, prepared from the known hMATE1 inhibitor cimetidine, reduced the norfloxacin resistance of HmrM-expressing strains by 92% at non-cytotoxic concentrations in human cells, and multidrug resistance protein MdtK-expressing strains by 86%. These results indicated that the inhibitor is a lead candidate for the development of drugs with a novel mechanism of action against infections caused by multidrug-resistant bacteria that act synergistically with antimicrobial drugs.


Assuntos
Anti-Infecciosos , Norfloxacino , Humanos , Norfloxacino/farmacologia , Proteínas de Bactérias/metabolismo , Proteínas de Membrana Transportadoras , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Bactérias/metabolismo
7.
Beilstein J Org Chem ; 18: 1567-1574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483094

RESUMO

A series of aryl fluoroalkenyl ethers that contain chlorine and bromine as well as fluorine atoms were prepared in moderate to good yields via the reactions of phenols and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) in the presence of KOH. This simple reaction enabled the construction of highly halogenated compounds with the potential for further functionalization. The reaction involved a highly reactive difluoroethylene intermediate, which was produced by the reaction between halothane and KOH.

8.
Beilstein J Org Chem ; 18: 1642-1648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530534

RESUMO

A rhodium-catalyzed intramolecular reductive aldol-type cyclization is described to give ß-hydroxylactones with high diastereoselectivities. The stereoselectivity of this cyclization is highly solvent dependent and can give syn- or anti-ß-hydroxylactones with high diastereoselectivity. This methodology was also applied to the synthesis of a chiral necic acid lactone which is a structural component of the pyrrolizidine alkaloid monocrotaline.

9.
Chem Pharm Bull (Tokyo) ; 69(9): 905-912, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34470955

RESUMO

Herein, we describe the design and synthesis of cimetidine analogs, as well as their inhibitory activity toward the human multidrug and toxin extrusion transporter 1 (hMATE1), which is related to nephrotoxicity of drugs. Cimetidine is the histamine H2-receptor antagonist, but also inhibits hMATE1, which is known to cause renal impairment. We designed and synthesized cimetidine analogs to evaluate hMATE1 inhibitory activity to reveal whether the analogs could reduce the inhibition of hMATE1. The results showed that all analogs with an unsubstituted guanidino group exhibited hMATE1 inhibitory activity. On the other hand, there was a clear difference in the hMATE1 inhibitory activity for the other compounds. That is, compounds with a methylimidazole ring exhibited hMATE1 inhibition, while compounds with a phenyl ring did not. The results suggest that the ability to form hydrogen bonds at the azole moiety is strongly involved in the hMATE1 inhibition.


Assuntos
Azóis/farmacologia , Cimetidina/farmacologia , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Azóis/química , Cimetidina/síntese química , Cimetidina/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
10.
Chem Pharm Bull (Tokyo) ; 69(6): 557-563, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34078802

RESUMO

Sperm activation is an essential process by which the male gametes become capable of fertilization. Because the process in Caenorhabditis elegans is readily reproducible in vitro, this organism serves as an excellent model to investigate it. C. elegans sperm activation in vivo occurs during spermiogenesis. Membranous organelles (MOs) contained within spermatids fuse with the plasma membrane, resulting in extracellular release of their contents and relocation of some proteins indispensable for fertilization from the MO membrane onto the sperm surface. Intriguingly, these cytological alternations are exhibited similarly in mouse spermatozoa during the acrosome reaction, which also represents a form of sperm activation, prompting us to hypothesize that C. elegans and mice share a common mechanism for sperm activation. To explore this, we first screened a chemical library to identify compounds that activate C. elegans spermatozoa. Because a quinolinol analog named DDI-6 seemed to be a candidate sperm activator, we synthesized it to use for further analyses. This involved direct dechlorination and hydrogenolysis of commercially available 5-chloro-8-quinolinol, both of which are key steps to yield 1,2,3,4-tetrahydro-8-quinolinol, and we subsequently introduced the sulfonamide group to the compound. When C. elegans spermatids were stimulated with solvent alone or the newly synthesized DDI-6, approx. 3% and approx. 28% of spermatids became MO-fused spermatozoa, respectively. Moreover, DDI-6 triggered the acrosome reaction in approx. 20% of mouse spermatozoa, while approx. 12% became acrosome-reacted after mock stimulation. Thus, DDI-6 serves as a moderately effective activator for both C. elegans and mouse spermatozoa.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Hidroxiquinolinas/farmacologia , Espermatozoides/efeitos dos fármacos , Animais , Caenorhabditis elegans/metabolismo , Hidroxiquinolinas/síntese química , Hidroxiquinolinas/química , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Espermatozoides/metabolismo
11.
Nihon Ronen Igakkai Zasshi ; 58(2): 272-283, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34039804

RESUMO

AIM: We developed a program to promote community activities for preventing frailty using the Community-as-Partner model. We aimed to clarify whether or not participants' extent of practice relating to frailty prevention activities increased after the classroom, as well as the effectiveness of the program for preventing frailty. METHODS: The participants were recruited from among pre-frailty and frailty individuals in a cohort study of community-dwelling older adults. Thirty-two participants completed the classroom intervention. Thereafter, every three months, through a telephone survey, the participants were asked about the extent of practice regarding their frailty prevention activities. The Kihon Checklist and Japanese version of the Cardiovascular Health Study (J-CHS) frailty index were surveyed as outcome measures during the cohort study conducted six months before the classroom (baseline [BL]) as well as approximately one year after this intervention (follow-up [FL]). The changes in the outcome measures between the BL and FL in the intervention group were compared to those in the control group matched by the propensity score. RESULTS: The frailty prevention activities saw a maximum increase around six to nine months after the classroom. The J-CHS frailty index showed a group × time-of-survey significant interaction (F = 6.531, p=0.012) and significantly decreased from 1.3 at BL to 0.8 at FL in the intervention group (p=0.009). CONCLUSIONS: The practice of activities relating to frailty prevention increased after the classroom, and the participants also showed improvements in their physical frailty. The present program seems likely to be effective preventing frailty.


Assuntos
Fragilidade , Idoso , Estudos de Coortes , Idoso Fragilizado , Fragilidade/prevenção & controle , Avaliação Geriátrica , Humanos , Vida Independente , Inquéritos e Questionários
12.
Beilstein J Org Chem ; 17: 89-96, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33519995

RESUMO

An efficient and convenient method for the synthesis of structurally unique and highly functionalized aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers has been developed. This approach exhibits a broad reaction scope, a simple operation and without the need of any expensive transition-metal catalyst, highly toxic or corrosive reagents. Notably, we demonstrate the potential utility of halothane for the synthesis of aryl gem-difluoroalkyl ethers containing the bromochloromethyl group.

13.
J Magn Reson Imaging ; 51(3): 727-733, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31373136

RESUMO

BACKGROUND: An understanding of potential age-related changes in brain stiffness and its regional variation is important for further clinical application of MR elastography. PURPOSE: To investigate the effect of age on global and regional brain stiffness in young and middle-aged adults. STUDY TYPE: Prospective. SUBJECTS: Fifty subjects with normal brains and aged in their 20s, 30s, 40s, 50s, or 60s (five men, five women per decade). FIELD STRENGTH/SEQUENCE: 3.0T MRI and elastography with a vibration frequency of 60 Hz. ASSESSMENT: Stiffness was measured in nine brain regions (cerebrum, temporal lobes, sensorimotor areas, frontotemporal composite region, deep gray matter and white matter (deep GM/WM), parietal lobes, occipital lobes, frontal lobes, and cerebellum) using an atlas-based region-of-interest approach. The influence of age on regional brain stiffness was evaluated. STATISTICAL TESTS: Multiple linear regression analysis, followed by Dunnett's multiple comparisons test, using subjects in their 20s as controls. RESULTS: Following adjustment for sex, multiple linear regression revealed a significant negative correlation between age and stiffness of the cerebrum (P < 0.0001), temporal lobes (P < 0.0001), sensorimotor areas (P < 0.0001), frontotemporal composite region (P < 0.0001), deep GM/WM (P = 0.0028), parietal lobes (P < 0.0001), occipital lobes (P = 0.0055), and frontal lobes (P < 0.0001). Dunnett's multiple comparison test showed that the stiffness of the sensorimotor areas, frontotemporal composite region, and frontal lobes was significantly decreased in subjects in their 40s (P < 0.0367), 50s (P < 0.0001), and 60s (P < 0.0001), while that of the cerebrum, temporal lobes, and parietal lobes was significantly decreased only in subjects in their 50s (P < 0.0012) and 60s (P < 0.0031) when compared with the controls. DATA CONCLUSION: There is an age-related decrease in brain stiffness that varies across the different regions. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:727-733.


Assuntos
Cérebro , Técnicas de Imagem por Elasticidade , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
J Org Chem ; 85(7): 5104-5108, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32141749

RESUMO

A mild and convenient reaction for oxidative trifluoromethylation of terminal alkenes was developed using in situ generated AgCF3 in the presence of a copper catalyst. The reaction proceeded under an air atmosphere to afford trifluoromethylated allylic compounds in moderate to good yield. This reaction, with no need for highly hygroscopic or corrosive reagents, features not only a simple operation but also various functional group tolerances.

15.
J Org Chem ; 85(2): 1253-1258, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31851516

RESUMO

A series of aniline-based fluorophores were newly synthesized. To increase their fluorescence quantum yields, it was particularly important to substitute 3,3,3-trifluoroprop-1-enyl (TFPE) groups next to the amino group to benefit from an extended π-electron delocalization. Among these, 5-CN-2-TFPE-aniline was found to behave as an excellent fluorophore with a reasonable fluorescence quantum yield of 0.89 even in aqueous solution. l-Alanine peptide, a nonfluorescent analogue of 5-CN-2-TFPE-aniline, was synthesized and successfully employed as an enzyme probe to detect aminopeptidase N activity.


Assuntos
Corantes Fluorescentes/síntese química , Processos Fotoquímicos , Elétrons , Fluorescência
16.
Nihon Koshu Eisei Zasshi ; 67(8): 518-527, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32879238

RESUMO

Objectives We hypothesized that the motivation for improving physical function could be increased by increasing the awareness of social role expectations among frail community-dwelling older adults through an intervention based on the Community-as-Partner (CAP) model. We also developed a program for supporting community activities to prevent frailty, utilizing the CAP model. Program feasibility was assessed by implementing it under the local government's frailty prevention service.Methods The CAP-based program consisted of a "learning period," a "regional issue extraction period," and a "practice period," scheduled once a week for four months. Public health nurses and/or physical therapists assisted with the program. The intervention was conducted with a cohort study of community-dwelling older adults. About 160 participants identified as frail and pre-frail on the Kihon Checklist were recruited. Program feasibility was assessed through participation rate, number of pre-frail and frail individuals, and drop-out rate; scores of a pre-post intervention questionnaire assessing the understanding of frailty and regional resources; and behavioral change stage on frailty prevention.Results A total of 42 participants were recruited (participation rate=26.3%; 25 were pre-frail and 17 were frail). The drop-out rate was 23.8% (n=10). The scores on four out of five items and six out of eleven items on the understanding of frailty and regional resources, respectively, improved significantly after the intervention. Regarding the behavioral change stage, 26 participants (81.2%) maintained or improved.Conclusion The participation rate was approximately 30%, similar to conventional programs with direct professional intervention. Conversely, a higher drop-out rate compared to conventional programs suggested the importance of explaining the workshop in the program introduction and publicizing the workshop. The results indicated that the program improved the understanding of frailty and regional resources, and led to behavioral change for frailty prevention.


Assuntos
Fragilidade/prevenção & controle , Educação de Pacientes como Assunto , Serviços Preventivos de Saúde , Saúde Pública , Apoio Social , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Vida Independente , Masculino , Inquéritos e Questionários
17.
Beilstein J Org Chem ; 16: 1411-1417, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32647543

RESUMO

Fluorescent molecules based on a fluorinated isoxazole scaffold were synthesized and investigated for their photochemical properties. The introduction of a fluorine substituent into 3,5-diarylisoxazoles led to an increase of fluorescence intensity and exhibited a redshift in the emission intensity. α-Fluorinated boron ketoiminates (F-BKIs) were also synthesized via a ring-opening reaction of 4-fluoroisoxazoles and exhibited highly fluorescent luminescence and aggregation-induced emission (AIE), showing promise as a new fluorophore.

18.
Org Biomol Chem ; 17(10): 2818-2823, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30801599

RESUMO

Fluorine-alkoxy group exchange reactions of fluorinated isoxazoline derivatives promoted by Lewis acids to give various 5-alkoxylated 4,4-difluoroisoxazolines via SN1 type processes in good to excellent yields are reported. Sterically demanding phenol substrates such as 2,6-diphenylphenol gave novel aryl substituted products via electrophilic aromatic substitution.

19.
Bioorg Med Chem ; 27(9): 1789-1794, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30898436

RESUMO

We have synthesized a fluorinated analogue of indomethacin bearing a 3,3,3-trifluoroprop-1-enyl group at its 2-position and evaluated its inhibitory activity towards the COX-1 and COX-2 enzymes in vitro. The results revealed that this fluorinated analogue exhibited much greater inhibitory activity and selectivity towards COX-2 than indomethacin. The increased affinity between the fluorinated analogue and COX-2 was attributed to a significant increase in van der Waals contacts (i.e. van der Waals contributions in ΔG were -13.80 kcal/mol for COX-1 and -18.46 kcal/mol for COX-2), explaining an effect of the fluorine substituent in enzyme selectivity. This newly synthesized fluorinated analogue therefore represents a potent and selective COX-2 inhibitor.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Indometacina/química , Sítios de Ligação , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/metabolismo , Indometacina/metabolismo , Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína , Eletricidade Estática
20.
Rinsho Ketsueki ; 59(3): 269-274, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-29618683

RESUMO

A 73-year-old man with left parotid gland swelling over 2 months was referred to our hospital in March 201X. Purpura on the lower legs had been recurrent for >20 years. Biopsy of the parotid gland demonstrated diffuse infiltration of abnormal lymphocytes that were negative for CD10 and positive for CD19, CD20, and κ-chain. The Ki-67 positivity was <10%; lymphoepithelial lesions were observed. The patient was diagnosed with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). Chromosome analysis revealed t (X;14) (p11.2;q32), and fluorescence in situ hybridization (FISH) of metaphase spreads showed three signals of the immunoglobulin heavy chain (IGH) gene on the derivative chromosomes X and 14, besides the normal chromosome 14. CT findings of parotid glands were suggestive of Sjogren syndrome, and biopsy of the purpura on the leg demonstrated leukocytoclastic vasculitis. In the literature, only seven patients with lymphoma and t (X;14) translocation have been reported. Of these, five patients had MALT lymphoma, one had nodal marginal zone lymphoma, and one had diffuse large B-cell lymphoma. In all patients, lymphoma evolved from previous autoimmune diseases. It is suggested that MALT lymphoma with the t (X;14) translocation forms a new entity of lymphoma.


Assuntos
Linfoma de Zona Marginal Tipo Células B/diagnóstico , Vasculite Leucocitoclástica Cutânea/patologia , Idoso , Cromossomos Humanos Par 14/genética , Cromossomos Humanos X/genética , Humanos , Hibridização in Situ Fluorescente , Linfoma de Zona Marginal Tipo Células B/genética , Masculino , Translocação Genética
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