scholarly journals Establishing the concept of aza-[3 + 3] annulations using enones as a key expansion of this unified strategy in alkaloid synthesis

2013 ◽  
Vol 9 ◽  
pp. 1170-1178 ◽  
Author(s):  
Aleksey I Gerasyuto ◽  
Zhi-Xiong Ma ◽  
Grant S Buchanan ◽  
Richard P Hsung

A successful enone version of an intramolecular aza-[3 + 3] annulation reaction is described here. Use of piperidinium trifluoroacetate salt as the catalyst and toluene as the solvent appears to be critical for a successful annulation. We also demonstrated for the first time that microwave irradiation can accelerate aza-[3 + 3] annulation reactions. An attempt to expand the scope of the enone aza-[3 + 3] annulation was made in the form of propyleine synthesis as a proof of concept. While synthesis of the enone annulation precursor was successfully accomplished, the annulation proved to be challenging and was only modestly successful.

2020 ◽  
Vol 54 (2) ◽  
pp. 497-513 ◽  
Author(s):  
L. N. Beldiman ◽  
I. N. Urbanavichene ◽  
V. E. Fedosov ◽  
E. Yu. Kuzmina

We studied in detail a moss-lichen component of Shokalsky Island vegetation for the first time and identified 79 species of mosses and 54 species and 2 subspecies of lichens and lichenicolous fungi. All species of mosses and 23 species and 2 subspecies of lichens and lichenicolous fungi are recorded for the first time for the island. The study is based on collections made in South West part of the island, in arctic tundra. We also explored the participation of the mosses and lichens in the main types of plant communities and the species distribution in 10 ecotopes. The paper describes the noteworthy findings (Abrothallus parmeliarum, Aongstroemia longipes, Arthonia peltigerea, Caloplaca caesiorufella, Catillaria stereocaulorum, Ceratodon heterophyllus, Lecanora leptacinella, Sphagnum concinnum, S. olafii) and features of bryo- and lichenoflora of Shokalsky Island.


2012 ◽  
Vol 6 ◽  
pp. CMC.S8976 ◽  
Author(s):  
Yousif Ahmad ◽  
Gregory Y.H. Lip

Atrial fibrillation is the commonest arrhythmia worldwide and is a growing problem. AF is responsible for 25% of all strokes, and these patients suffer greater mortality and disability. Warfarin has traditionally been the only successful therapy for stroke prevention, but its limitations have resulted in underutilisation. Major progress has been made in AF research, leading to improved management strategies. Better risk stratification permits identification of truly low-risk patients who do not require anticoagulation and we are able to simplify ourevaluation of a patient's bleeding risk. The advent of novel anticoagulants means warfarin is no longer the only choice for stroke prophylaxis. These drugs circumvent many of warfarin's inconveniences, but only long-term study and use will conclusively demonstrate how they compare to warfarin. The landscape of stroke prevention in AF has changed with effective alternatives to warfarin available for the first time in 60 years—but each new option brings new considerations.


1988 ◽  
Vol 135 ◽  
Author(s):  
M. O. Manasreh ◽  
D. O. Pederson ◽  
T. S. Aurora

AbstractMeasurements of the ultrasonic attenuation and velocity have been made in solid electrolytes with fluorite structure, PbF2, BaF2, and CdF2, from room temperature to temperature at or above the diffuse solid electrolyte transition temperature, Tc. The ultrasonic attenuation peaks observed in this class of materials are associated only with the ionic conductivity saturation rather than in combination with crystallographic phase transition found in many other solid electrolytes. The relaxation rates and Arrhenius activation energies for anion motion above the transition temperature were obtained from the temperature dependence of the ultrasonic attenuation and the theory of local site fluctuations. The ultrasonic attenuation peaks observed for the first time in CdF2was used to define the diffuse transition temperature in this material. An Anomalous peak is also observed in the linear thermal expansion coefficient of PbF2.


2020 ◽  
Vol 12 (4) ◽  
pp. 358-367
Author(s):  
Nikolai V. Belenov

Introduction. The article presents the results of research of the geographical vocabulary of the Shilan dialect, one of the Erzya-Mordovian dialects of the Samara region, common among Erzya population of Shilan village in Krasnoyarsk region. The dialect belongs to rare Mordovian dialects of the Samara Volga region that were formed in the region since the middle of the XIX century, and therefore its research is of extra interest. Materials and Methods. The research methods are determined by the purpose and objectives of the study. The analysis of the geographical vocabulary of the Shilan dialect is carried out with the involvement of relevant items made in other Mordovian dialects of Samara region, adjacent territories of neighboring regions, as well as other territories of settlement of the Mordovians. Data on geographical vocabulary of the dialect introduced into research for the first time. The main source materials for the article is based on field studies in Silane village during the field seasons in 2017 and 2020, as well as in other Erzya-Mordovian and Moksha-Mordovian villages of Samara region and adjacent territories in 2015 – 2020. Results and Discussion. The study showed that the geographical vocabulary of the Shilan dialect of the Erzya-Mordovian language is significantly different from the corresponding lexical clusters in other dialects of the Mordovian region, which can be explained by natural geographical conditions surrounding Shilan village and the original composition of this lexical cluster of Erzya immigrants who founded this village. Conclusion. The analysis of the geographical vocabulary of the Shilan dialect allowed, on the one hand, to identify specific features of this cluster that distinguish it from the corresponding materials of other Mordovian dialects of the region, and, on the other hand, to identify common isoglosses between it and a number of the Erzya-Mordovian dialects of the Samara Volga region.


2021 ◽  
pp. 8-20

Micellar therapy has become a usefully viable treatment arm in various fields, ranging from oncology to bioimaging. As such, research leading to any improvements or adaptations in administration and techniques can have far-reaching consequences. Potential aspects of prebiotic chemistry may also be explored in such research as well. To that end, proof-of-concept experiments were performed to elucidate a possible mechanism of action for prebiotic protocell division. Representative potentially prebiotically plausible biomolecules, i.e., a fatty acid, amino acid, and nucleotide were mixed and heated in water and subjected to microscopic examination for observation of possible self-division and laboratory testing for the presence of polypeptides and polynucleotides (Biuret, MALDI mass-spec, etc.) with and without the presence of nucleotide. The results are presented for the first time here and a mechanism is proposed that best fits the data obtained. The evolutionary, e.g., prebiotic biomolecular cooperativity, and clinical, e.g., potential antineoplastic micellar/vesicular therapy, ramifications are discussed as well. Keywords: Micelle; Liposome; Protocell; MRNA; Self-division; Mechanism; Solid tumors


Author(s):  
Ivan Zykin

In the period of New Economic Policy in the USSR industrialization issues became very topical. In timber industry complex, the solutions were related to the development of forested areas in Northeastern regions of the country as well as to the construction and reconstruction of enterprises. The article provides the first-time analysis of maps and forest industry location, based on the results of the First Five-Year Plan published in the atlas “The Industry in the USSR and the beginning of the Second Five-Year Plan“ and statistical collection materials ”Social Construction of the USSR”. The analysis was made in order to define the situation in the industry, the main directions of production as well as the regional specificities. Using the example of wood machining sphere the author presents the analysis of enterprise groups according to different criteria. The research resulted in conclusions about highest intensity of enterprise reconstruction and construction in timber sawing, in furniture industry and intra-sectoral combination. In timber industry, the majority of enterprises were small and middle companies, which greatly contributed to its development. Regional specificities of timber industry location included concentration of main facilities in northwestern, western and central parts of the country, in the Volga region and in Ural. However only several regions had developed wood machining and deep processing spheres, such as Leningrad oblast, the Gorky Krai, Belarusian and the Ukrainian Soviet Republics.


Author(s):  
Maya Montañez Smukler

Elaine May began her career as a filmmaker during the 1970s when the mythology of the New Hollywood male auteur defined the decade; and the number of women directors, boosted by second wave feminism, increased for the first time in forty years. May’s interest in misfit characters, as socially awkward as they were delusional, and her ability to seamlessly move them between comedy and drama, typified the New Hollywood protagonist who captured America’s uneasy transition from the hopeful rebellion of the 1960s into the narcissistic angst of the 1970s. However, the filmmaker’s reception, which culminated in the critical lambast of her comeback film Ishtar in 1987, was uneven: her battles with studio executives are legendary; feminist film critics railed against her depiction of female characters; and a former assistant claimed she set back women directors by her inability to meet deadlines. This chapter investigates Elaine May’s career within the lore 1970s Hollywood to understand the industrial and cultural circumstances that contributed to the emergence of her influential body of work; and the significant contributions to cinema she made in spite of, and perhaps because of, the conflicts in which she was faced.


2020 ◽  
pp. 137-179
Author(s):  
Iain Crawford

Building on the case made in chapter 3, chapter 4 tunes to consider Martin Chuzzlewit and examines the ways in which the novel addresses the relationship between literacy, print media, and the experience of modern urbanism. Together eith its predecessor, the chapter argues that for Dickens America was far more than what has been generally perceived as an increasingly negative experience that chastened his understanding of the press and of mass culture. Rather, and notwithstanding all his complaints about Americans, tobacco, and spit, the encounter with America in fact provided him with a new sense, at once disturbing and alluring, of the potential power of a cheap mass-market press led by entrepreneurial editors operating in a print environment unconstrained by state controls. Moreover, in writing about America, and above all in writing about its newspapers in both American Notes and Martin Chuzzlewit, Dickens for the first time discovered a methodology for fusing fiction and the press in ways that would be foundational his most significant contribution to Victorian journalism, Household Words and its successor, All the Year Round.


Author(s):  
Robin R. Hurst ◽  
Julia Tucker Lloyd ◽  
Jennifer C. Miller

This chapter provides a case study describing the process of using theory in practice in implementing higher level evaluation of training initiatives within one unit of a global financial services organization. The organization has used Kirkpatrick's level one and two evaluations for many years to evaluate training. This case describes the first time a level three evaluation was used, covering why it was necessary, the process for developing, as well as the outcomes of the evaluation. This chapter also describes the influence of organizational culture in the decisions made in the implementation of the evaluation strategy.


2019 ◽  
Vol 47 (14) ◽  
pp. e82-e82
Author(s):  
Choong Yong Ung ◽  
Mehrab Ghanat Bari ◽  
Cheng Zhang ◽  
Jingjing Liang ◽  
Cristina Correia ◽  
...  

Abstract With the emergence of genome editing technologies and synthetic biology, it is now possible to engineer genetic circuits driving a cell's phenotypic response to a stressor. However, capturing a continuous response, rather than simply a binary ‘on’ or ‘off’ response, remains a bioengineering challenge. No tools currently exist to identify gene candidates responsible for predetermining and fine-tuning cell response phenotypes. To address this gap, we devised a novel Regulostat Inferelator (RSI) algorithm to decipher intrinsic molecular devices or networks that predetermine cellular phenotypic responses. The RSI algorithm is designed to extract gene expression patterns from basal transcriptomic data in order to identify ‘regulostat’ constituent gene pairs, which exhibit rheostat-like mode-of-cooperation capable of fine-tuning cellular response. Our proof-of-concept study provides computational evidence for the existence of regulostats and that these networks predetermine cellular response prior to exposure to a stressor or drug. In addition, our work, for the first time, provides evidence of context-specific, drug–regulostat interactions in predetermining drug response phenotypes in cancer cells. Given RSI-inferred regulostat networks offer insights for prioritizing gene candidates capable of rendering a resistant phenotype sensitive to a given drug, we envision that this tool will be of great value in bioengineering and medicine.


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