RESUMEN
A palladium-catalyzed annulative π-extension reaction of bay-iodinated triphenylenes with aryl iodides/o-chloroaromatic carboxylic acids was developed. This approach enabled the synthesis of diverse polycyclic aromatic compounds, including dibenzo[fg,op]tetracenes, azadibenzo[fg,op]tetracenes, and tribenzo[a,g,m]coronenes. Initial studies indicate that the resulting product, 2,3,8,9,14,15-hexakis(decyloxy)tribenzo[a,g,m]coronene, exhibits good liquid-crystalline properties.
RESUMEN
A palladium-catalyzed bay-region annulative π-extension reaction of o-halobiphenyls with o-chloropyridinecarboxylic acids was developed. The reaction was carried out with a 1 : 1 ratio of substrates. A variety of azatriphenylene derivatives could be synthesized by this approach. This transformation could be applied to the synthesis of ionic liquid-crystalline molecules.
Asunto(s)
Compuestos Aza , Paladio , Paladio/química , Catálisis , CrisenosRESUMEN
Flavors and fragrances (F&F) are interesting organic compounds in chemistry. These compounds are widely used in the food, cosmetic, and medical industries. Enzymatic synthesis exhibits several advantages over natural extraction and chemical preparation, including a high yield, stable quality, mildness, and environmental friendliness. To date, many oxidoreductases and hydrolases have been used to biosynthesize F&F. Ene-reductases (ERs) are a class of biocatalysts that can catalyze the asymmetric reduction of α,ß-unsaturated compounds and offer superior specificity and selectivity; therefore, ERs have been increasingly considered an ideal alternative to their chemical counterparts. This review summarizes the research progress on the use of ERs in F&F synthesis over the past 20 years, including the achievements of various scholars, the differences and similarities among the findings, and the discussions of future research trends related to ERs. We hope this review can inspire researchers to promote the development of biotechnology in the F&F industry.
Asunto(s)
Aromatizantes , Aromatizantes/química , Aromatizantes/metabolismo , Aromatizantes/síntesis química , Biocatálisis , Oxidorreductasas/metabolismo , Oxidorreductasas/química , Oxidorreductasas/genética , Perfumes/química , BiotecnologíaRESUMEN
With the continuous development of drug screening technology, new screening methodologies and technologies are constantly emerging, driving drug screening into rapid, efficient and high-throughput development. Microfluidics is a rising star in the development of innovative approaches in drug discovery. In this article, we summarize the recent years' progress of microfluidic chip technology in drug screening, including the developmental history, structural design, and applications in different aspects of microfluidic chips on drug screening. Herein, the existing microfluidic chip screening platforms are summarized from four aspects: chip structure design, sample injection and drive system, cell culture technology on a chip, and efficient remote detection technology. Furthermore, this review discusses the application and developmental prospects of using microfluidic chips in drug screening, particularly in screening natural product anticancer drugs based on chemical properties, pharmacological effects, and drug cytotoxicity.
Asunto(s)
Técnicas de Cultivo de Célula , Microfluídica , Evaluación Preclínica de Medicamentos/métodosRESUMEN
BACKGROUND: Gut microbiota is an emerging field of research, with related research having breakthrough development in the past 15 years. Bibliometric analysis can be applied to analyze the evolutionary trends and emerging hotspots in this field. AIM: To study the subject trends and knowledge structures of gut microbiota related research fields from 2004 to 2018. METHODS: The literature data on gut microbiota were identified and downloaded from the PubMed database. Through biclustering analysis, strategic diagrams, and social network analysis diagrams, the main trend and knowledge structure of research fields concerning gut microbiota were analyzed to obtain and compare the research hotspots in each period. RESULTS: According to the strategic coordinates and social relationship network map, Clostridium Infections/microbiology, Clostridium Infections/therapy, RNA, Ribosomal, 16S/genetics, Microbiota/genetics, Microbiota/immunology, Dysbiosis/immunology, Infla-mmation/immunology, Fecal Microbiota Transplantation/methods, Fecal Microbiota Transplantation can be used as an emerging research hotspot in the past 5 years (2014-2018). CONCLUSION: Some subjects were not yet fully studied according to the strategic coordinates; and the emerging hotspots in the social network map can be considered as directions of future research.