Relation between chemical structure and insecticidal activity in pyrethroid compounds. I. An analogue of chrysanthemic acid containing chlorine in the side chain

1959 ◽  
Vol 24 (7) ◽  
pp. 2230-2236 ◽  
Author(s):  
J. Farkaš ◽  
P. Kouřím ◽  
F. Šorm
Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1789
Author(s):  
Dmitry Tolmachev ◽  
George Mamistvalov ◽  
Natalia Lukasheva ◽  
Sergey Larin ◽  
Mikko Karttunen

We used atomistic molecular dynamics (MD) simulations to study polyelectrolyte brushes based on anionic α,L-glutamic acid and α,L-aspartic acid grafted on cellulose in the presence of divalent CaCl2 salt at different concentrations. The motivation is to search for ways to control properties such as sorption capacity and the structural response of the brush to multivalent salts. For this detailed understanding of the role of side-chain length, the chemical structure and their interplay are required. It was found that in the case of glutamic acid oligomers, the longer side chains facilitate attractive interactions with the cellulose surface, which forces the grafted chains to lie down on the surface. The additional methylene group in the side chain enables side-chain rotation, enhancing this effect. On the other hand, the shorter and more restricted side chains of aspartic acid oligomers prevent attractive interactions to a large degree and push the grafted chains away from the surface. The difference in side-chain length also leads to differences in other properties of the brush in divalent salt solutions. At a low grafting density, the longer side chains of glutamic acid allow the adsorbed cations to be spatially distributed inside the brush resulting in a charge inversion. With an increase in grafting density, the difference in the total charge of the aspartic and glutamine brushes disappears, but new structural features appear. The longer sides allow for ion bridging between the grafted chains and the cellulose surface without a significant change in main-chain conformation. This leads to the brush structure being less sensitive to changes in salt concentration.


2003 ◽  
Vol 69 (3) ◽  
pp. 1670-1679 ◽  
Author(s):  
Annett Mikolasch ◽  
Elke Hammer ◽  
Frieder Schauer

ABSTRACT Sixty-one strains of alkane-oxidizing bacteria were tested for their ability to oxidize N-(2-hexylamino-4-phenylimidazol-1-yl)-acetamide to imidazol-2-yl amino acids applicable for pharmaceutical purposes. After growth with n-alkane, 15 strains formed different imidazol-2-yl amino acids identified by chemical structure analysis (mass and nuclear magnetic resonance spectrometry). High yields of imidazol-2-yl amino acids were produced by the strains Gordonia rubropertincta SBUG 105, Gordonia terrae SBUG 253, Nocardia asteroides SBUG 175, Rhodococcus erythropolis SBUG 251, and Rhodococcus erythropolis SBUG 254. Biotransformation occurred via oxidation of the alkyl side chain and produced 1-acetylamino-4-phenylimidazol-2-yl-6-aminohexanoic acid and the butanoic acid derivative. In addition, the acetylamino group of these products and of the substrate was transformed to an amino group. The product pattern as well as the transformation pathway of N-(2-hexylamino-4-phenylimidazol-1-yl)-acetamide differed in the various strains used.


Author(s):  
Renato IORI ◽  
Gina R. DE NICOLA ◽  
Manuela BAGATTA ◽  
Eleonora PAGNOTTA

Dietary intake of Brassicaceae (Crucifers) provides not only nutrients, but also a highly interesting class of secondary metabolites beneficial to health, known as glucosinolates (GLs). These compounds possess a -D-glucopyranosyl unit connected to a O-sulfated anomeric Z-thiohydroximate function, and a side chain R which is the only variable part of the chemical structure. Up to now, more than 120 naturally-occurring GLs have been carachterized


2011 ◽  
Vol 250-253 ◽  
pp. 984-989 ◽  
Author(s):  
Zhi Yong Liu ◽  
Chong Cui ◽  
Li Li

Based on the analysis of the chemical structure of polycarboxylate-type SPs grafted PEO side chains, as well as sulfonic and carboxylic acid groups, a kind of polycarboxylate-based SPs grafted varied PEO side chains were synthesized by using radical polymerisation techniques.The relative dispersing effectiveness of the SPs was evaluated in cement paste and concrete by measuring paste flow and concrete slumps. The test results indicat that the copolymers with shorter PEO side chains (with 9 and 14 EO units) give lower initial dispersing power but higher time retention,with the prolonging of PEO side chains the higher initial dispersing effect and the lower time retention can be received. The excellent dispersing property and time retention of synthesized SPs for cementious systems can be achieved by grafted long side chain(with 45 EO units) integrated with short side chain(9 or 14 EO) at the backbone of anionic polymer.


2012 ◽  
Vol 236-237 ◽  
pp. 731-735
Author(s):  
Chang Su ◽  
Ling Min Wang ◽  
Li Huan Xu ◽  
Jun Lei Liu ◽  
Fang Yang ◽  
...  

A copolymer of 4-(1H-pyrrol-1-yl)phenol (PLPY) and pyrrole ( P(PLPY-co-Py) )was synthesized. And the chemical structure and battery performance of the prepared materials were characterized comparably by 1H NMR, FT-IR spectra and galvanostatic charge-discharge testing using simulant lithium ion half-cell method, respectively. The results shows that the introduction of the phenol group to the pyrrole as a rigid side chain could prevent the polymer from agglomeration and optimize the particle morphology of the resulting polymers, all of which made it demonstrate a significantly improved specific capacity (73.9 mAh•g-1) compared with PPy (21.4 mAh•g-1)


1961 ◽  
Vol 39 (10) ◽  
pp. 1906-1914 ◽  
Author(s):  
A. G. McInnes ◽  
F. P. Cooper ◽  
J. A. MacDonald

The distillable esters of heated linseed oil contain a fraction, designated NAFD, which fails to form an adduct with urea. NAFD itself has now been separated into three fractions by gas-liquid partition chromatography. The chemical structure of these component esters was investigated by means of their infrared spectra and by analysis of the products obtained on oxidation of the esters with periodate–permanganate. It is concluded that all the components have the same carbon skeleton, namely, 1-propyl-2-alkenecarboxycyclohexene, but differ in the position of the double bond in the side chain.


1964 ◽  
Vol 160 (979) ◽  
pp. 246-257 ◽  

Previously reported work in this series (Brown, Rimington & Sawyer 1963) produced evidence that icterogenic activity (i.a.) of the pentacyclic triterpene acids is based upon the presence of a β-equatorially orientated hydroxyl group at C (3), or a hydroxyl at C (24), and a 22β-angeloyloxy side chain in the molecule of the particular active compound. The second part of this work, dealing with certain structural variations in triterpenes of the oleanane, 24-noroleanane (hedragane) and ursane series, is reported in this paper. These variations involve i.a. esterification of the C (28) carboxyl, saturation of the 22β-angeloyl side chain or replacement of this by simple saturated aliphatic acids. Assays are recorded of a further thirteen of these compounds for icterogenic activity using the modified technique described in the second paper of this series (Brown et al . 1963). It has been concluded from this work that the icterogenicity of 3β- or 24β-hydroxy triterpene acids is undoubtedly associated with the 22β-angeloyloxy side chain. Removal of the esterifying group at C (22) or its replacement by a simple saturated fatty acid residue is followed by complete loss of activity. Esterification of the C (28) carboxyl produces a considerable decrease in icterogenic potency due, probably, to a decrease in solubility of the compound.


Author(s):  
Yamada Yuzo ◽  
Inouye Goro ◽  
Tahara Yasutaka ◽  
Kondo Keiji

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