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Updated: Jun 1, 2026

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Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis
Published on: November 17, 2011
9-Eth-oxy-1,5,13-trimethyl-8,10-dioxa-tetra-cyclo-[7.7.1.0.0]hepta-deca-2,4,6,11,13,15-hexa-ene
Abstract:
The reaction of ethyl acetoacetate with meta-cresol in an acidic ionic liquid yielded a complex mixture of condensation products. 4,7-Dimethyl-coumarin and the title compound, C(20)H(22)O(3), were isolated. The title compound shows chemical but not crystallographic mirror symmetry. The two aromatic rings are inclined at an angle of 73.55 (6)°.
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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...
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Cyclic ethers are heterocyclic compounds with an oxygen atom in the ring along with carbon atoms. They are named depending on the number of carbon atoms present in their ring system. Cyclic ethers with a three-membered ring system are called “oxirane”, four-membered ring systems as “oxetane”, five-membered ring systems as “oxolane”, and six-membered ring systems as “oxane”. The cyclic structure of these rings imposes angle strain, and this strain is more in the ring having a smaller number of...
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Based on their attached substituent groups, ethers can be classified into two...
Ethers are organic compounds with an ether functional group which is characterized by an oxygen atom connected to two — identical or different — alkyl, aryl, or vinyl groups. The C–O–C linkage in dimethyl ether — the simplest ether — has an approximately tetrahedral bond angle of 110.3 degrees. The oxygen atom is sp3- hybridized, with the C–O distance being about 140 pm.
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In cyclohexane, the substituents can occupy different positions generating distinct isomers.
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Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
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