Methyl Dehydroabietate Research Articles

Diterpenoids. XXXVI. Synthesis of d-kaurene and d-phyllocladene from l-abietic acid.

d-Kaurene (XXXVI) and d-phyllocladene (XXXVII) were synthesized from l-abietic acid (I) via intramolecular carbenoid reaction of diazoketones and subsequent cleavage of the resulting cyclopropyl ring with Li-liq. NH3. Methyl dehydroabietate (XVI) and dehydroabietane (V) introduced from I were used as the starting materials. The improved synthesis of V was also described.

Diterpenoids. XXX. Reaction of methyl dehydroabietate derivatives with aluminum chloride under effect of electron-donating group.

Reactions of methyl dehydroabietate derivatives having electron-donating group at aromatic C-ring with aluminum chloride were examined. It became clear that the reaction proceeded through isomerisation of 9, 10-bond and/or deisopropylation and the direction of the reaction is affected by the substituent at the aromatic C-ring. For instance, the reaction of 12-hydroxy ester (7) proceeded through both routes while 14-hydroxy ester (19) was selectively deisopropylated. Interconversion between cis- and trans-stereoisomers of deisopropyl ester (e.g., 10h9) was observed and the former is predominant in the equilibrium.

Diterpenoids. XXXI. Reaction of methyl dehydroabietate derivatives with aluminum chloride under effect of electron-withdrawing group. Synthesis of methyl deisopropyldehydroabietate series.

Reaction of 12-acetyl ester (5) with aluminum chloride gave predominant trans-isomer (6) in company with the cis (7). trans-Isomer had not been observed as major product in the reactions of methyl dehydroabietate having electron-donating group at aromatic ring as described previously. In the other cases of reactions of methyl dehydroabietate derivatives having electron-withdrawing group, 7-oxo ester (20) did not react even under the drastic condition. But 7-oxo ester having a hydroxyl or a methoxyl group at 12-or 14-position was deisopropylated to give only the respective trans deisopropyl isomer.

Diterpenoids. XXIX. Nitration of Methyl Dehydroabietate Derivatives

The nitration of methyl dehydroabietate derivatives having a hydroxyl and methoxyl group as in methyl 12-hydroxy-dehydroabietate and methyl 12-methoxy-dehydroabietate gave only 11-substituted compound. However, methyl 12-bromo-dehydroabietate was nitrated in different behavior and gave more complex result.

The Thermal Behavior of Methyl Dehydroabietate at 600–800 °C

Methyl dehydroabietate was pyrolyzed on Vycor rod at 600, 700, and 800 °C with varying contact times. Some 40–60 products were observed upon g.l.p.c. analysis, with the number of products decreasing with increasing temperature and increasing contact time at 800 °C. Considerable carbon formation was found to occur at 800 °C and long contact times. The 24 major products which could readily be separated by preparative g.l.p.c. methods were collected and identified. The high yield of naphthalene-related compounds obtained is explained by the thermal rupture of the A-ring which is initiated by elimination of the carbomethoxy moiety.

Diterpenoids. XXIII. The synthesis of the C4 epimers of methyl abietate, methyl palustrate, and methyl dehydroabietate

Diterpenoids. XXIII. The synthesis of the C4 epimers of methyl abietate, methyl palustrate, and methyl dehydroabietate

Microbial degradation of methyl dehydroabietate

Microbial degradation of methyl dehydroabietate

The Oxidation of Methyl Dehydroabietate by Molecular Oxygen

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Oxidation of Methyl Dehydroabietate by Molecular OxygenPaul F. Ritchie, Thomas F. Sanderson, and Lane F. McBurneyCite this: J. Am. Chem. Soc. 1953, 75, 11, 2610–2612Publication Date (Print):June 1, 1953Publication History Published online1 May 2002Published inissue 1 June 1953https://doi.org/10.1021/ja01107a016RIGHTS & PERMISSIONSArticle Views132Altmetric-Citations9LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (429 KB) Get e-Alerts Get e-Alerts