Enzymatic Desaturation of Fatty Acids: Δ11 Desaturase Activity on Cyclopropane Acid Probes
摘要:
The formation of methylenecyclopropanes by enzymatic desaturation of 11-cyclopropylundecanoic acid (1) and its disubstituted derivatives cis- and trans-3-5 has been investigated using the Delta(11) desaturase of Spodoptera littoralis as model enzyme. Gas chromatography coupled to mass spectrometry analyses of methanolyzed lipidic extracts from tissues incubated with each probe revealed that all the cyclopropyl fatty acids were transformed into the corresponding 11-cyclopropylidene acids, except for compound trans-5 (5b), which was not desaturated at C11. The formation of methylenecyclopropane 9 as the only reaction product from 1 indicates that a potential radical intermediate is too short-lived to allow rearrangement reactions. Information on the Delta(11) desaturase substrate binding domain is provided considering the cyclopropyl probes 3-5 as conformationally restricted analogues of the straight-chain substrates.
Enzymatic Desaturation of Fatty Acids: Δ11 Desaturase Activity on Cyclopropane Acid Probes
摘要:
The formation of methylenecyclopropanes by enzymatic desaturation of 11-cyclopropylundecanoic acid (1) and its disubstituted derivatives cis- and trans-3-5 has been investigated using the Delta(11) desaturase of Spodoptera littoralis as model enzyme. Gas chromatography coupled to mass spectrometry analyses of methanolyzed lipidic extracts from tissues incubated with each probe revealed that all the cyclopropyl fatty acids were transformed into the corresponding 11-cyclopropylidene acids, except for compound trans-5 (5b), which was not desaturated at C11. The formation of methylenecyclopropane 9 as the only reaction product from 1 indicates that a potential radical intermediate is too short-lived to allow rearrangement reactions. Information on the Delta(11) desaturase substrate binding domain is provided considering the cyclopropyl probes 3-5 as conformationally restricted analogues of the straight-chain substrates.
stereochemistry of the chiral centers could not be determined because it was difficult to collect a sufficient amount of the natural pheromone, the plain structures of I and II were confirmed by synthesis of the racemic mixtures starting from diols. These methyl-branched ketones have not been identified as a natural product, indicating that they constitute a new chemical group of lepidopteran female sex pheromones
developed for the synthesis of aliphatic fluorinated methyl ethers (ROCH2RF), specifically monofluoromethyl ethers (ROCH2F) and trifluoromethylthiomethyl ethers (ROCH2SCF3), through pyridinium-type salt intermediates derived from methoxymethyl (MOM) ethers. The addition of a fluorine source (F− or SCF3−) to the pyridinium-type salts afforded the corresponding fluorinated methyl ethers in good yields under
CYCLOPHOSPHAZENE COMPOUND, LUBRICANT COMPRISING SAME, AND MAGNETIC DISK
申请人:MORESCO Corporation
公开号:EP2565198A1
公开(公告)日:2013-03-06
A cyclophosphazene compound of the formula (I), and lubricants and magnetic disks using the compound
wherein n is 2, 3 or 4, m is an integer of 1 to 12, R is C1-4 fluoroalkyl and Rf is -CF2O(CF2CF2O)x(CF2O)yCF2- or -CF2CF2O(CF2CF2CF2O)zCF2CF2- in which x, y and z are each 0 or a positive real number to give a number average molecular weight of 500 to 4000 to a fluoropolyether of the formula HOCH2-Rf-CH2OH including said Rf, the fluoropolyether having a molecular weight distribution (PD) of 1.0 to 1.5.
The formation of methylenecyclopropanes by enzymatic desaturation of 11-cyclopropylundecanoic acid (1) and its disubstituted derivatives cis- and trans-3-5 has been investigated using the Delta(11) desaturase of Spodoptera littoralis as model enzyme. Gas chromatography coupled to mass spectrometry analyses of methanolyzed lipidic extracts from tissues incubated with each probe revealed that all the cyclopropyl fatty acids were transformed into the corresponding 11-cyclopropylidene acids, except for compound trans-5 (5b), which was not desaturated at C11. The formation of methylenecyclopropane 9 as the only reaction product from 1 indicates that a potential radical intermediate is too short-lived to allow rearrangement reactions. Information on the Delta(11) desaturase substrate binding domain is provided considering the cyclopropyl probes 3-5 as conformationally restricted analogues of the straight-chain substrates.