Bicyclic Diterpenoids Research Articles

Racemic syntheses of agelasimine-A and agelasimine-B, bicyclic diterpenoids from the marine sponge Agelas mauritiana

The first racemic syntheses of agelasimines-A and -B, adenine-related bicyclic diterpenoids from the marine sponge Agelas mauritiana, have been accomplished by means of routes through the diol 10 as a key intermediate for their common diterpene portion. As a result, their structures and relative stereochemistries have been unequivocally established to be those represented by formulas (±)- 1a and (±)- 2a, respectively.

Taxachitrienes A and B, two new bicyclic taxane diterpenoids from Taxus chinensis

Two new bicyclic taxane diterpenoids, taxachitrienes A(1) and B(2), were isolated from the needles of Taxus chinensis. Their structure were elucidated on the basis of spectroscopic data. The crystal structure of 2 was also presented. It is the first time for the isolation of bicyclic diterpenoid which is proposed as the biogenetic precursor for taxanes.

ChemInform Abstract: Tobacco Chemistry. Part 73. 4,6,8‐Trihydroxy‐11‐capnosene‐2,10‐dione, a New Cembrane‐Derived Bicyclic Diterpenoid from Tobacco.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Tobacco chemistry. 73. 4,6,8-trihydroxy-11-capnosene-2,10-dione, a new cembrane-derived bicyclic diterpenoid from tobacco.

A new diterpenoid containing a rare carbobicyclic cembrane-derived skeleton, the capnosane skeleton, has been isolated from flowers of Greek tobacco. It has been identified as (1S*,3R*,4S*,6R*,7R*,8R*,11Z)-4,6,8-trihydroxy-11-capnosene- 2,10-dione by spectral methods and X-ray analysis of the corresponding benzoate. A full account of the X-ray work is given.

Palominol, a new diterpene based on the dolabellane skeleton from the caribbean gorgonian octocorals eunicea calyculata and eunicea laciniata

A new bicyclic diterpenoid, palominol ( 2), of the dolabellane ring system has been isolated from the Caribbean gorgonians Eunicea calyculata and Eunicea laciniata . The structure of this new compound was assigned on the basis of chemical and spectral studies, particularly heteronuclear chemical shift correlation methods, homonuclear spin decoupling experiments and nuclear Overhauser enhancement difference spectroscopy (NOEDS).

Two New Bicyclic Diterpenoids from the Brown Alga Glossophora kuntii

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTwo New Bicyclic Diterpenoids from the Brown Alga Glossophora kuntiiA. Patricio Rivera, Luis A. Astudillo, Antonio G. Gonzalez, Eduardo Manta, and Fernando CataldoCite this: J. Nat. Prod. 1987, 50, 5, 965–967Publication Date (Print):September 1, 1987Publication History Published online1 July 2004Published inissue 1 September 1987https://doi.org/10.1021/np50053a038RIGHTS & PERMISSIONSArticle Views115Altmetric-Citations4LEARN 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 (200 KB) Get e-Alerts Get e-Alerts

Agelasine-A, -B, -C and -D, novel bicyclic diterpenoids with a 9-methyladeninium unit possessing inhibitory effects on na,K-atpase from the okinawa sea sponge [formula omitted] sp. 1)

Agelasine-A, -B, -C and -D, novel bicyclic diterpenoids having inhibitory effects on enzymic reactions of Na,K-ATPase, have been isolated from the orange colored Okinawan sea sponge Agelas sp. and the structures have been determined on the basis of their spectral data and chemical conversions.

MERCURY(II) TRIFLATE—AMINE COMPLEX-INDUCED CYCLIZATION OF GERANYLGERANYL p-NITROBENZOATE: SYNTHESIS OF SPONDIAN AND LABDANE DITERPENOIDS

Abstract Biomimetic cyclization of geranylgeranyl p-nitrobenzoate by the mercury(II) triflate—N,N-dimethylaniline complex and subsequent reductive demercuration provide a tricyclic and two bicyclic diterpenoids in moderate yields. This is the first example of the cyclization of geranylgeraniol to the tricyclic diterpene.

The structure of vulgarol — A new diterpenoid from Marrubium vulgare

The structure and stereochemistry of a new minor diterpenoid, vulgarol, isolated from the plantMarrubium vulgare L. has been shown. It has been established that it belongs to the bicyclic diterpenoids with the cis (5β, 10β) linkage of the A/B rings.

Dehydrobromination of methyl 11α-bromo-12-oxopodocarpan-19-oate

The configuration and stereochemistry of methyl 11α-bromo-12-oxopodocarpan-19-oate 1 have been determined by application of the nuclear Overhauser effect. The dehydrobromination of 1 with dimethylacetamide–calcium carbonate results in a predominant 1,4-elimination process which for short reaction periods yields the non-conjugated ketone 8 and for long reaction periods yields the conjugated ketone 2. The 1,2-elimination of hydrogen bromide is a minor process and takes place to the extent of 20–22%. The ketone 8 has been oxidatively cleaved to the keto-acid 11, a valuable intermediate for the synthesis of bicyclic diterpenoids.

Optical rotation and structure in the labdane series of diterpenoids

The correlation between optical rotation and structure in the labdane series of bicyclic diterpenoids is discussed with reference to 143 compounds.