103665-39-0Relevant articles and documents
BITRANSFORMATION OF 1,8--CINEOLE BY CULTURED CELLS OF EUCALYPTUS PERRINIANA
Orihara, Yutaka,Furuya, Tsutomu
, p. 641 - 644 (1994)
Four new biotransformation products, (1R,2R,4S)-1,8-epoxy-p-menthan-2-yl O-β-D-glucopyranoside, (1S,3R,4R)- and (1R,3S,4S)-1,8-epoxy-p-menthan-3-yl O-β-D-glucopyranosides, and (1S,2S,4R)-1,8-epoxy-p-menthan-2-yl O-β-D-glucopyranosyl-(1-->6)-β-D-glucopyranoside, together with a known (1S,2S,4R)-1,8-epoxy-p-menthan-2-yl O-β-D-glucopyranoside were isolated from a cell suspension culture of Eucalyptus perriniana following administration of 1,8-cineole.
Cineole biodegradation: Molecular cloning, expression and characterisation of (1R)-6β-hydroxycineole dehydrogenase from Citrobacter braakii
Slessor, Kate E.,Stok, Jeanette E.,Cavaignac, Sonia M.,Hawkes, David B.,Ghasemi, Younes,De Voss, James J.
, p. 81 - 86 (2010)
The first steps in the biodegradation of 1,8-cineole involve the introduction of an alcohol and its subsequent oxidation to a ketone. In Citrobacter braakii, cytochrome P450cin has previously been demonstrated to perform the first oxidation to produce (1R)-6β-hydroxycineole. In this study, we have cloned cinD from C. braakii and expressed the gene product, which displays significant homology to a number of short-chain alcohol dehydrogenases. It was demonstrated that the gene product of cinD exhibits (1R)-6β-hydroxycineole dehydrogenase activity, the second step in the degradation of 1,8-cineole. All four isomers of 6-hydroxycineole were examined but only (1R)-6β-hydroxycineole was converted to (1R)-6-ketocineole. The (1R)-6β-hydroxycineole dehydrogenase exhibited a strict requirement for NAD(H), with no reaction observed in the presence of NADP(H). The enzyme also catalyses the reverse reaction, reducing (1R)-6-ketocineole to (1R)-6β-hydroxycineole. During this study the N-terminal His-tag used to assist protein purification was found to interfere with NAD(H) binding and lower enzyme activity. This could be recovered by the addition of Ni2+ ions or proteolytic removal of the His-tag.
Syntheses of chiral 1,8-cineole metabolites and determination of their enantiomeric composition in human urine after ingestion of 1,8-cineole- containing capsules
Schaffarczyk, Monika,Balaban, Teodor Silviu,Rychlik, Michael,Buettner, Andrea
, p. 77 - 85 (2013/06/27)
The chiral metabolites in human urine were investigated after ingestion of a 1,8-cineole (eucalyptol)-containing enterocoated capsule (Soledum). For identification of the various enantiomers the enantiomerically pure (-/+)-α2-hydroxy-1,8- cineole, (-/+)-β2-hydroxy-1,8-cineole, (-/+)-9-hydroxy-1,8-cineole, and (-/+)-2-oxo-1,8-cineole were prepared. To achievethis aim, after acetylation of the synthesized racemic 2-and 9-hydroxy-1,8-cineoles, pig liver esterase- or yeast-mediated hydrolysis provided the (-)-alcohols with their antipodal(+)-acetates with enantiomeric excess of 33-100 %. Dess-Martin periodinane oxidation of the alcohol (+)-α2-hydroxy-1,8-cineole, obtained by hydrolysis of the resolved acetate, provided the corresponding (+)-2-oxo-1,8-cineole, meanwhile the oxidation of (-)-α2-hydroxy-1,8-cineole gave (-)-2-oxo-1,8-cineole. Using these standards seven metabolites (+/-)-α2-hydroxy-1,8-cineole, (+/-)-β2-hydroxy-1,8-cineole, (+/-)-α3-hydroxycineole,(+/-)-3-oxo-1, 8-cineole, 4-hydroxy-1,8-cineole, 7-hydroxy-1,8-cineole, and (+/-)-9-hydroxy-1,8-cineole, all liberated from their glucuronides, were identified in urine by GCMS on a chiral stationary phase after consumption of 10 mg of 1,8-cineole. Metabolite screening using 2H3-1,8- cineol as the internal standard revealed (+/-)-α2-hydroxy-1,8-cineole as the predominant metabolite followed by (+/-)-9-hydroxy-1,8-cineole. Furthermore, the results showed that one enantiomer is always formed preferentially.
Enantiomeric purity and odor characteristics of 2- and 3-acetoxy-1,8- cineoles in the rhizomes of Alpinia galanga Willd.
Kubota, Kikue,Someya, Yuki,Yoshida, Reiko,Kobayashi, Akio,Morita, Tetsu-Ichiro,Koshino, Hiroyuki
, p. 685 - 689 (2007/10/03)
(S)-(+)-O-methylmandelate esters of trans- and cis-1,3,3-trimethyl-2- oxabicyclo[2.2.2]octan-5- and 6-ols (2- and 3-hydroxy-1,8-cineoles) were prepared, and eight diastereomers were separated. The absolute configuration of the asymmetric carbons of the cineole moiety of each diastereomer was determined by 1H NMR data according to the Mosher theory. Each mandelate was reduced with LiAlH4 to obtain optically pure hydroxy-1,8-cineoles, this being followed by acetylation to afford optically pure acetoxy-1,8-cineoles. These acetates were subjected to chiral GC, using a cyclodextrin column, and the enantiomeric purity of trans- and cis-1,3,3-trimethyl-2- oxabicyclo[2.2.2]octan-5-and 6-yl acetates in the aroma concentrate from the rhizomes of Alpinia galanga was determined as 93.9 (5S), 19.4 (5R), 63.5 (6R), and 100 (6R) % ee, respectively. The aroma character of each enantiomer was also evaluated by GC-sniffing.
