Studies on gibberellin synthesis. The preparation of phenanthrenoid intermediates for the synthesis of gibberellin A21

1981 ◽  
Vol 34 (9) ◽  
pp. 1913 ◽  
Author(s):  
LN Mander ◽  
GJ Potter ◽  
SG Pyne ◽  
M Woolias
Keyword(s):  
Conjugate Addition ◽  
Dimethyl Malonate ◽  
Conventional Methods

Methyl 3-(6'-oxo-4'-methoxy-5',6',7',8'-tetrahydronaphthalen-1'-yl)propanoate (11) was converted by conventional methods into diazoketone (17) which underwent acid-promoted cyclization to dienone (18). Refunctionalization gave dienone (20) which was subjected to a tandem alkylation, conjugate addition process with the sodium enolate of dimethyl malonate to furnish a 2: 1 mixture of dimethyl (2RS,8aSR,10aSR)-2-methoxymethyloxy-10,12-dioxo-2,3,4,5,6,7,8a,9,10-decahydro-1 H-2,10a-ethano- phenanthrene-8,8-dicarboxylate (21) and its 8a-epimer, respectively. Subsequent manipulations led to lactone (26), but attempts to convert this compound into a gibbane derivative were unsuccessful.

Epalons: Synthesis of New 16α-Carboxymethyl Derivatives

1999 ◽  
Vol 64 (9) ◽  
pp. 1479-1484 ◽  
Author(s):  
Barbora Slavíková ◽  
Alexander Kasal
Keyword(s):  
Formic Acid ◽  
Conjugate Addition ◽  
Dimethyl Malonate ◽  
Diethyl Azodicarboxylate

The title compounds (16α-carboxymethyl-3α-hydroxy-5α-pregnan-20-one and its sodium and triethylammonium salts) were prepared from 20-oxopregna-5,16-dien-3β-yl acetate by conjugate addition of dimethyl malonate and decarboxylation. Inversion of configuration at carbon C-3 was carried out by Mitsunobu acylation with diethyl azodicarboxylate and formic acid in the presence of triphenylphosphine.

Spin-polarized Scanning Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 768-769
Author(s):  
Kazuyuki Koike ◽  
Hideo Matsuyama
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Speed ◽  
Magnetic Thin Films ◽  
Electron Spin Polarization ◽  
Acquisition Time ◽  
Magnetization Direction ◽  
Spin Polarized ◽  
Conventional Methods ◽  
Scanning Electron

Spin-polarized scanning electron microscopy (spin SEM), where the secondary electron spin polarization is used as the image signal, is a novel technique for magnetic domain observation. Since its first development by Koike and Hayakawa in 1984, several laboratories have extensively studied this technique and have greatly improved its capability for data extraction and its range of applications. This paper reviews the progress over the last few years.Almost all the high expectations initially held for spin SEM have been realized. A spatial resolution of several hundreds angstroms has been attained, which is nearly one order of magnitude higher than that of conventional methods for thick samples. Quantitative analysis of magnetization direction has been performed more easily than with conventional methods. Domain observation of the surface of three-dimensional samples has been confirmed to be possible. One of the drawbacks, a long image acquisition time, has been eased by combining highspeed image-signal processing with high speed scanning, although at the cost of image quality. By using spin SEM, the magnetic structure of a 180 degrees surface Neel wall, magnetic thin films, multilayered films, magnetic discs, etc., have been investigated.

The Need Inventory of Sensation Seeking (NISS)

2012 ◽  
Vol 28 (1) ◽  
pp. 11-18 ◽  
Author(s):  
Marcus Roth ◽  
Philipp Hammelstein
Keyword(s):  
Sensation Seeking ◽  
Reliability And Validity ◽  
Assessment Method ◽  
Factorial Structure ◽  
Conventional Methods ◽  
New Research ◽  
Sensation Seeking Scale ◽  
Temperamental Trait ◽  
Nonclinical Study

Based on the conception of sensation seeking as a need rather than a temperamental trait ( Hammelstein, 2004 ), we present a new assessment method, the Need Inventory of Sensation Seeking (NISS), which is considered to assess a motivational disposition. Three studies are presented: The first examined the factorial structure and the reliability of the German versions of the NISS; the second study compared the German and the English versions of the NISS; and finally, the validity of the NISS was examined in a nonclinical study and compared to the validity of conventional methods of assessing sensation seeking (Sensation Seeking Scale – Form V; SSS-V). Compared to the SSS-V, the NISS shows better reliability and validity in addition to providing new research possibilities including application in experimental areas.

Eco-Friendly Synthesis of Pyrazoline Derivatives

2017 ◽  
Vol 9 (04) ◽  
Author(s):  
Mahesh G. Kharatmol ◽  
Deepali Jagdale
Keyword(s):  
Ionic Liquids ◽  
Microwave Irradiation ◽  
Organic Synthesis ◽  
Ultrasonic Irradiation ◽  
Minimal Energy ◽  
Anticancer Activities ◽  
Conventional Methods

Pyrazoline class of compounds serve as better moieties for an array of treatments, they have antibacterial, antifungal, antiinflammatory, antipyretic, diuretic, cardiovascular activities. Apart from these they also have anticancer activities. So, pertaining to its importance, many attempts are made to synthesize pyrazolines. Since conventional methods of organic synthesis are energy and time consuming. There are elaborate pathways for green and eco-friendly synthesis of pyrazoline derivatives including microwave irradiation, ultrasonic irradiation, grinding and use of ionic liquids which assures the synthesis of the same within much lesser time and by use of minimal energy

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