85514-25-6Relevant academic research and scientific papers
Oxidative C-ring opening of abietane diterpenes with ammonium cerium(IV) nitrate
Marrero, Joaquín González,San Andrés, Lucía,Luis, Javier Gutiérrez
, p. 1127 - 1129 (2007)
The oxidation reaction of 11,12-di-O-methylcarnosol with ammonium cerium(IV) nitrate (CAN) gave an abietane diterpene with the C-ring opened and a diester function. The structure of this diester was established by spectroscopic analysis and by chemical means. The reaction of 11,12-di-O-dimethylgaldosol with CAN gave a similar result, yielding a δ-lactone which structure was established as 7-hydroxy-11,12-seco-8,13- abietadien-12,7:20,6β-dilacton-11-oic acid methyl ester by spectroscopic analysis and chemical means. These results could be useful to accede to other natural products like rosmic acid Georg Thieme Verlag Stuttgart.
Rearrangement of methyl 11,12-di-O-methyl-6,7-didehydrocarnosate in basic medium. Easy hemisynthesis of miltirone
Luis, Javier G.,Andres, Lucia S.,Fletcher, Winston Q.,Lahlou, El Hassane,Perales, Aurea
, p. 2207 - 2211 (2007/10/03)
Methyl 11,12-di-O-methyl-6,7-didehydrocarnosate 3, obtained from the abundant natural product carnosol 1, undergoes an interesting rearrangement when treated with potassium tert-butoxide in dimethyl sulfoxide to give 11,12-dimethoxy-20(10→7)abeo-abieta-5(10),8,11,13-tetraen-20-oic acid 4, in which an additional double bond is formed between C-5 and C-10 and the carboxylic acid group has migrated from C-10 to C-7. Deprotection of the two methyl ether moieties in 4 with BBr3 allows spontaneous air oxidation and decarboxylation of the catechol derivative to give the potent benzodiazepine agonist miltirone 10. The structure of 6 has been unequivocally elucidated by X-ray diffraction analysis and indirect chemical correlation between 4 and 6 has been established.
A New Diterpene Lactone, Rosmadial, from Rosemary (Rosmarinus officinalis L.)
Nakatani, Nobuji,Inatani, Reiko
, p. 353 - 358 (2007/10/02)
A new type of phenolic diterpene lactone, named rosmadial (1), was isolated from the leaves of rosemary (Rosmarinus officinalis L.), one of the herb spices belonging to the Family Labiatae.The structure has been determined to be 12-hydroxy-6,7-seco-11,10-epoxymethano-20-oxo-abieta-8,11,13-triene-6,7-dial by chemical and spectroscopic methods.The structure and stereochemistry were confirmed by synthesis from carnosol.
Isolation, structure determination, and absolute configuration of barbatusol: A new bioactive diterpene with a rearranged abietane skeleton from the labiate Coleus barbatus
Kelecom
, p. 3603 - 3608 (2007/10/02)
Barbatusol, isolated from the Labiate Coleus barbatus Bentham, is shown to be a new phenolic diterpene with a rearranged abietane skeleton. Absolute configuration is established by hemisynthesis of barbatusol dimethyl-ether from the known carnosol. Barbatusol is endowed with biological activity.
Antioxidative Effect of the Constituents of Rosemary (Rosmarinus officinalis L.) and Their Derivatives
Inatani, Reiko,Nakatani, Nobuji,Fuwa, Hidetsugu
, p. 521 - 528 (2007/10/02)
Antioxidative activity was measured on extracts of rosemary (Rosmarinus officinalis L.), one of the herb spices belongs to the Family Labiatae, using different solvents.Strong activity was observed in the weakly acidic fraction of the n-hexane extract, which was further fractionated and purified to afford several active compounds.An odorless and colorless compound, named rosmanol, showed high antioxidative activity in both lard and linoleic acid, and particularly in lard, was about four times more active than synthetic antioxidants, such as BHT and BHA.Furthermore, the antioxidant activities of the derivatives of rosmanol and carnosol were measured by the ferric thiocyanate method and the TBA method, to observe the correlation between chemical structure and activity as an antioxidant.
