- Synthesis, olfactory evaluation and determination of the absolute configuration of the β- and γ-Iralia isomers
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The regioselective synthesis of the methyl-ionone isomers 6-9 is described. The enantiomers of the γ-isomers 8 and 9 are prepared by enzyme-mediated resolution of the corresponding 4-hydroxy derivatives followed by reductive elimination of the hydroxy group. The absolute configuration of the latter compound is determined by chemical correlation with the known α-isomers. Since all the isomers obtained are components of the artificial violet odourants sold under the trade name of Iralia, their odour properties are evaluated by professional perfumers.
- Barakat, Assem,Brenna, Elisabetta,Fuganti, Claudio,Serra, Stefano
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experimental part
p. 2316 - 2322
(2009/04/11)
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- Retinoids and related compounds. Part 22. Synthesis of β-ionone analog tricarbonyliron complexes
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The synthesis of β-ionone analog tricarbonyliron complexes was investigated. N-Methoxy-N-methyl-(2,6,6-trimethyl-1-clohexen-1-yl)-2- propenamide (Weinreb amide), prepared from the corresponding ethyl ester and N,O-dimethylhydroxylamine hydrochloride, reacted smoothly with various organometallic reagents to afford the β-ionone analogs in good to excellent yields. Treatment of these compounds with dodecacarbonyltriiron afforded the corresponding tricarbonyliron complexes in high yields.
- Wada, Akimori,Fujioka, Naoko,Ito, Masayoshi
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p. 171 - 176
(2007/10/03)
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- Cycloalkane derivatives
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A cycloalkane derivative represented by the formula (I): STR1 wherein A, R2, R3, R4, R5, R6, R7, Z, and n are as defined in the specification. The compounds of formula (I) exhibit activities against peptic ulcers and are useful as therapeutic and prophylactic agents for peptic ulcers.
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- Synthesis of three retinal models, including the 10-s-cis-locked retinal, all-E-12,19-methanoretinal
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All-E-12,19-methanoretinal (1) is distinguished by the presence of the locked 10-s-cis conformation in the cyclohexadiene ring in the conjugated chain. 1 has been prepared together with its 13-Z isomer in an overall yield of 0.5percent. 1 and 13-Z-1 photochemically interconvert in a clean way.In this system, only photoisomerization around the C13=C14 double bond is observed.In the photostationary state, the 13-Z isomer is predominant.All-E-12-ethyl-19-methylretinal (2) and all-E-12-ethylretinal (3) were prepared in good overall yields (20percent and 30percent) from β-ionone using the novel synthon, 3-methyl-4-(diethylphosphono)-2-hexenenitrile (11).The photochemistry of these retinal derivatives is very similar to that of retinal.The 9-Z, 11-Z and 13Z isomers of 2 and 3 were photochemically prepared.The 13C NMR spectra of these new compounds gave information about the structural elements of alkyl groups in conjugated systems and about the conformation of the conjugated chain.
- Groesbeek, M.,Steen, R. van der,Vliet, J. C. van,Vertegaal, L. B. J.,Lugtenburg, J.
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p. 427 - 436
(2007/10/02)
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