scholarly journals Systematic syntheses and characterization of dodecadien-1-ols with conjugated double bond, lepidopterous sex pheromones.

1985 ◽  
Vol 49 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Tetsu ANDO ◽  
Yuichi KUROTSU ◽  
Mieko KAIYA ◽  
Masaaki UCHIYAMA
Keyword(s):  
Double Bond ◽  
Sex Pheromones

scholarly journals Systematic Syntheses and Characterization of Dodecadien-1-olswith Conjugated Double Bond, Lepidopterous Sex Pheromones

1985 ◽  
Vol 49 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Tetsu Ando ◽  
Yuichi Kurotsu ◽  
Mieko Kaiya ◽  
Masaaki Uchiyama
Keyword(s):  
Double Bond ◽  
Sex Pheromones

scholarly journals Channeling of Eukaryotic Diacylglycerol into the Biosynthesis of Plastidial Phosphatidylglycerol

2006 ◽  
Vol 282 (7) ◽  
pp. 4613-4625 ◽  
Author(s):  
Markus Fritz ◽  
Heiko Lokstein ◽  
Dieter Hackenberg ◽  
Ruth Welti ◽  
Mary Roth ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Double Bond ◽  
Transgenic Plants ◽  
Phosphatidic Acid ◽  
Lipid Analysis ◽  
Photosynthetic Apparatus ◽  
Hexadecenoic Acid ◽  
Transgenic Tobacco Plants ◽  
Tobacco Plants

Plastidial glycolipids contain diacylglycerol (DAG) moieties, which are either synthesized in the plastids (prokaryotic lipids) or originate in the extraplastidial compartment (eukaryotic lipids) necessitating their transfer into plastids. In contrast, the only phospholipid in plastids, phosphatidylglycerol (PG), contains exclusively prokaryotic DAG backbones. PG contributes in several ways to the functions of chloroplasts, but it is not known to what extent its prokaryotic nature is required to fulfill these tasks. As a first step toward answering this question, we produced transgenic tobacco plants that contain eukaryotic PG in thylakoids. This was achieved by targeting a bacterial DAG kinase into chloroplasts in which the heterologous enzyme was also incorporated into the envelope fraction. From lipid analysis we conclude that the DAG kinase phosphorylated eukaryotic DAG forming phosphatidic acid, which was converted into PG. This resulted in PG with 2–3 times more eukaryotic than prokaryotic DAG backbones. In the newly formed PG the unique Δ3-trans-double bond, normally confined to 3-trans-hexadecenoic acid, was also found in sn-2-bound cis-unsaturated C18 fatty acids. In addition, a lipidomics technique allowed the characterization of phosphatidic acid, which is assumed to be derived from eukaryotic DAG precursors in the chloroplasts of the transgenic plants. The differences in lipid composition had only minor effects on measured functions of the photosynthetic apparatus, whereas the most obvious phenotype was a significant reduction in growth.

C60 Framework Response to Halogen Addition: the Stable Isomers of C60Br2m

1994 ◽  
Vol 47 (1) ◽  
pp. 131 ◽  
Author(s):  
JB Peel ◽  
RG Rothwell
Keyword(s):  
Double Bond ◽  
Molecular Orbital ◽  
High Stability ◽  
Structural Information ◽  
Spectroscopic Characterization ◽  
The Other ◽  
Semiempirical Calculations ◽  
Elementary Model ◽  
Local Distortion

The isolation and spectroscopic characterization of halogenated fullerene-60 compounds has not advanced greatly during the 2 years of effort in this area. While the fully fluorinated C60F60 has been studied in some detail, other halogen addition processes have indicated chlorination up to C60Cl24 and bromination up to C60Br24. However, definitive structural information has to date only been provided for three compounds, namely C60Br6, C60Br6 and C60Br24. Iodine does not appear to form genuine addition compounds. In the work reported here semiempirical calculations using the AM1 approximation with the MOPAC molecular orbital program have been directed to comparing the possible stable isomers of the 1:1 addition compounds C60X2 for X = F, Cl and Br. The favoured isomers can be described as 1,2-additions (to a double bond at a hexagon-hexagon fusion) and 1,4-additions (to the terminal carbons of a butadiene moiety) with higher-energy isomers resulting from 1,6- and 1,8-additions. The other isomers represented by 1,3- 1,5- and 1,7-additions are only stable relative to dissociation in the case of the fluorine addition compounds. By contrast for Br2 addition only the 1,2- and 1,4-isomers are stable toward dissociation. The calculations show that, at and near the addition site carbons, X2 addition is adequately described in terms of local distortion of the C60 sphere. The elementary model of C60 as comprising formal single and double bonds is relevant since C60 behaves as a 'poly- alkene ', with sp3 carbons replacing sp2 carbons at the addition sites. This model offers an explanation for the unique structures observed for C60Br6 and C60Br24 which the AM1calculations show to be very stable toward dissociation. However, the experimental C60Br8 structure is found to be relatively less stable than another isomer. Also high-stability isomers of C60Br4, C60Br10, C60Br12 and C60Br18 are predicted.

scholarly journals Preparation and Characterization of Reactive Type Dripping Agent Containing a-Double Bond

2014 ◽  
Vol 26 (24) ◽  
pp. 8577-8580
Author(s):  
Wenfei Li ◽  
Ruixiang Yao ◽  
Yang Lin ◽  
Zhanhai Yao ◽  
Shumei Liu
Keyword(s):  
Double Bond

The Characterization of Chitosan Nanoparticles by Raman Spectroscopy

2014 ◽  
Vol 665 ◽  
pp. 367-370 ◽  
Author(s):  
Xiao Dan Ren ◽  
Qing Shan Liu ◽  
Hui Feng ◽  
Xiao Ying Yin
Keyword(s):  
Raman Spectroscopy ◽  
Double Bond ◽  
Chitosan Nanoparticles ◽  
Carbon Double Bond

To study the performance of chitosan nanoparticles systematically, we characterized MMA, chitosan and synthesized chitosan nanoparticles by Raman spectroscopy. Through analyzing the characteristic peaks of each substance, we found MMA grafted chitosan by opening its carbon-carbon double bond. So Raman spectroscopy is a very effective way in terms of the characterization of nanomaterials .

scholarly journals Biocatalytic Asymmetric Alkene Reduction: Crystal Structure and Characterization of a Double Bond Reductase from Nicotiana tabacum

ACS Catalysis ◽  
2013 ◽  
Vol 3 (3) ◽  
pp. 370-379 ◽  
Author(s):  
David J. Mansell ◽  
Helen S. Toogood ◽  
John Waller ◽  
John M. X. Hughes ◽  
Colin W. Levy ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Nicotiana Tabacum ◽  
Double Bond Reductase

On Characterization of the CC Double Bond in Alkenes

1999 ◽  
Vol 10 (5) ◽  
pp. 451-471 ◽  
Author(s):  
M. Randić ◽  
M. Pompe
Keyword(s):  
Double Bond

Silyl-substituted α,β-Unsaturated Ketones from the Reaction of Silylvinylmetallic Reagents with Acid Anhydrides

1973 ◽  
Vol 51 (12) ◽  
pp. 2024-2032 ◽  
Author(s):  
A. G. Brook ◽  
J. M. Duff
Keyword(s):  
Double Bond ◽  
Low Temperatures ◽  
Silyl Group ◽  
Unsaturated Ketones ◽  
Carbon Double Bond ◽  
Benzoic Anhydride ◽  
Acid Anhydrides ◽  
By Products

The reactions of a series of silyl-substituted vinylmetallic reagents with acetic and benzoic anhydride have been investigated as a general route to α,β-unsaturated ketones having a silyl group attached to the carbon–carbon double bond. The reaction has been found to be generally applicable for acetyl derivatives provided low temperatures are used but the reaction with benzoic anhydride gives poorer results. The i.r. and u.v. spectra of the ketones are discussed. The characterization of novel 1,4-dienes obtained as by-products in the syntheses is also described.

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