scholarly journals Stereoselective and Stereospecific Triflate Mediated Intramolecular Schmidt Reaction: Easy Access to Alkaloid Skeletons

2021 ◽  
Author(s):  
Philippe Renaud ◽  
Lars Gnägi ◽  
Remo Arnold ◽  
Florence Giornal ◽  
Harish Jangra ◽  
...  
Keyword(s):  
Easy Access ◽  
Schmidt Reaction

Stereoselective and Stereospecific Triflate Mediated Intramolecular Schmidt Reaction: Easy Access to Alkaloid Skeletons

2020 ◽  
Author(s):  
Lars Gnägi ◽  
Remo Arnold ◽  
Florence Giornal ◽  
Harish Jangra ◽  
Ajoy Kapat ◽  
...  
Keyword(s):  
Theoretical Calculations ◽  
Easy Access ◽  
Chiral Alcohols ◽  
Schmidt Reaction ◽  
Salt Reduction ◽  
Iminium Salt ◽  
Whole Process ◽  
Structural Skeleton

The stereoselectivity and stereospecificity of the triflate mediated intramolecular Schmidt reaction of substituted 3-(1-azidocyclohexyl)propanol derivatives leading to octahydro-1<i>H</i>-pyrrolo[1,2-a]azepine, the structural skeleton of several important families of alkaloids such as the <i>Stemona</i> alkaloids, has been examined. The reaction involves an initial intramolecular S<sub>N</sub>2 reaction between the azide moiety and the triflate affording an intermediate spirocyclic aminodiazonoium salt that undergoes the expected 1,2-shift/N<sub>2</sub>-elimination followed by hydride mediated iminium salt reduction. Remarkably, chiral alcohols are converted to the azabicylic derivative with no or limited racemization. The initial asymmetric alcohol center controls the diastereoselectivity of the whole process leading to the formation of one out of the four possible diastereoisomers of disubstituted octahydro-1<i>H</i>-pyrrolo[1,2-a]azepine. The origin of the stereoselectivity is rationalized based on theoretical calculations. The concise synthesis of (–)-(<i>cis</i>)-3-propylindolizidine and (–)-(<i>cis</i>)-3-butyllehmizidine, two alkaloids found in the venom of workers of the ant <i>Myrmicaria melanogaster</i>, is reported.<br>

Framework for Semantic Search Enabled Software Component Repository (SSESCR)

2018 ◽  
Author(s):  
Vishnu Sharma ◽  
Vijay Singh Rathore ◽  
Chandikaditya Kumawat
Keyword(s):  
Software Quality ◽  
Software Reuse ◽  
Development Time ◽  
Software Component ◽  
Semantic Search ◽  
Easy Access ◽  
Software Components ◽  
Efficient Search ◽  
Systematic Reuse ◽  
New System

Software reuse can improve software quality with the reducing cost and development time. Systematic reuse plan enhances cohesion and reduces coupling for better testability and maintainability. Software reuse approach can be adopted at the highest extent if relevant software components can be easily searched, adapted and integrated into new system. Large software industries hold their own well managed component libraries containing well tested software component with the project category based classification .Access to these repositories are very limited. Software reuse is facing so many problems and still not so popular. This is due to issues of general access, efficient search and adoption of software component. This paper propose a framework which resolves all of the above issues with providing easy access to components, efficient incremental semantics based search, repository management, versioning of components.

Migration and US agricultural competitiveness

2013 ◽  
Vol 10 (2) ◽  
pp. 159-179 ◽  
Author(s):  
Philip L. Martin
Keyword(s):  
Farm Workers ◽  
Easy Access ◽  
Foreign Born ◽  
Guest Workers ◽  
Long Run ◽  
Short Run ◽  
Lower Wage ◽  
The Government ◽  
The One

Agriculture has one of the highest shares of foreign-born and unauthorized workers among US industries; over three-fourths of hired farm workers were born abroad, usually in Mexico, and over half of all farm workers are unauthorized. Farm employers are among the few to openly acknowledge their dependence on migrant and unauthorized workers, and they oppose efforts to reduce unauthorized migration unless the government legalizes currently illegal farm workers or provides easy access to legal guest workers. The effects of migrants on agricultural competitiveness are mixed. On the one hand, wages held down by migrants keep labour-intensive commodities competitive in the short run, but the fact that most labour-intensive commodities are shipped long distances means that long-run US competitiveness may be eroded as US farmers have fewer incentives to develop labour-saving and productivity-improving methods of farming and production in lower-wage countries expands.

Analisis Deskriptif Strategi Komunikasi Hotel Sakura Syariah

2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Nazwirman Nazwirman ◽  
Efendy Zein
Keyword(s):  
Local Government ◽  
Analytical Method ◽  
Marketing Mix ◽  
Communication Strategy ◽  
Easy Access ◽  
Marketing Communication ◽  
Integrated Marketing ◽  
Integrated Marketing Communication ◽  
Physical Evidence ◽  
Technology Process

The research objective describes an integrated marketing communication strategy in developing Sakura Syariah Hotel to see a comprehensive marketing communication strategy. Hotel Sakura Syariah is a 3-star syariah concept hotel which has 70 rooms. The analytical method uses the 7P (marketing mix) approach. The research results to increase the number of guests staying the strategy consisted of products, which offer a sharia concept with various types of representative rooms. Pricing, using the appropriate price preferences. Place, hotel location that is close to the center of the district capital and easy access. Promotion, with direct selling in accordance with local government and private selling by participating in various marketing events, sales proposals and advertising. People, conduct trainings to improve human resource capabilities. Physical evidence, a physical building that has Sharia characters and is supported by fairly good technology. Process, reservation service is quite fast and excellent. The development of this Sayriah hotel must be supported by related parties, especially the local government in order to increase the number of hotel guests

FLOOD ADAPTIVE SETTLEMENTS TOWARDS URBAN DEVELOPMENT IN THE RIPARIAN OF MEUREUDU RIVER, ACEH PROVINCE, INDONESIA

2019 ◽  
Vol 6 (2) ◽  
pp. 47
Author(s):  
Mirza Irwansyah ◽  
Cut Nursaniah ◽  
Laila Qadri
Keyword(s):  
Quantitative Methods ◽  
Secondary Data ◽  
Easy Access ◽  
Water Runoff ◽  
Pattern Design ◽  
The People ◽  
Large Numbers ◽  
Aceh Province ◽  
Secondary Data Sources ◽  
Residential Pattern

Meureudu Riparian in the past was a place of a collective settlements; it was then developed  to become a Meureudu City in Aceh Province, Indonesia. Initially, it was formed as traditional fishermen settlements but now has shifted into semi-modern settlements. However, the settlements developed sporadically to form an unplanned pattern of settlements. This condition resulted in low maintaining river and non-adaptive existence of the dwellings with the environment. Floods occur repeatedly in the river that affected great lost to the community. This study aimed to propose residential pattern design and adaptive settlements with Meureudu River riparian. Easy access roads to markets will facilitate economy growth to the people. This will also cause large numbers of unbridled migrants to enter and build settlements. In this study the a combination of quantitative methods based on interview data and questionnaires and qualitative exploratory methods based on field observation were used. The data were collected through observation, field measurement and secondary data sources. The results show that the condition of settlements along the river basin do not reflect the culture of the river. In order not to further aggravate the condition of the settlement and its impact on the occupants, we recommended two types of houses, namely in the form of stage and non-stage. The stage houses are located on the riverfront with an orientation overlooking the river. Additionally, undersea area can be used as security from the puddle of river water runoff during the flood and as a garden area and public while dry­­, while at a distance of 100 meters from the river non-stage houses form would be built because the runoff of flood water no longer affects the occupancy.

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