Tricyclic Intermediates Research Articles

The synthesis of the cyathins. Part 1. Synthesis of a tricyclic intermediate

The tricyclic diketoalcohol 5(3-phenylthio-6,9,10-trimethyl-12-hydroxytricyclo[7.4.0.02,6]trideca-2,10-diene-4,8-dione), a potential intermediate in the synthesis of the cyathins, has been prepared starting from 2,5-dimethyl-p-benzoquinone. The structure and stereochemistry of 5 was proven by an X-ray crystallographic study of the corresponding p-bromobenzoate (6). Attempts to isomerize the cis BC ring junction in 5 to give the corresponding trans compound were unsuccessful. Removal of the thiophenyl group from 5 gave compound 18a which on base-catalyzed isomerization provided an equilibrium mixture of the cis and trans compounds.

Reactions of phthalans with dienophiles. I. Synthesis of naphthalenes from phthalans and activated acetylenes

Diethoxyphthalans and activated acetylenes react at temperatures of 140–160 °C to yield substituted naphthalenes. It is proposed that the reaction occurs through the intermediacy of 1-ethoxyisobenzofurans generated thermally from the phthalans. The transient 1-ethoxyisobenzofurans are postulated to add to the acetylenes in a cycloaddition reaction to yield tricyclic intermediates that are transformed to naphthalenes at the elevated temperature of the reaction. Reactions with unsymmetrical acetylenes provided information on the regioselectivity of the reaction.

Steric control in prostaglandin synthesis involving bicyclic and tricyclic intermediates

Steric control in prostaglandin synthesis involving bicyclic and tricyclic intermediates

ChemInform Abstract: STEREOSPECIFIC TOTAL SYNTHESIS OF GIBBERELLIC ACID. A KEY TRICYCLIC INTERMEDIATE

Chemischer InformationsdienstVolume 10, Issue 12 Natural Products ChemInform Abstract: STEREOSPECIFIC TOTAL SYNTHESIS OF GIBBERELLIC ACID. A KEY TRICYCLIC INTERMEDIATE E. J. COREY, E. J. COREYSearch for more papers by this authorR. L. DANHEISER, R. L. DANHEISERSearch for more papers by this authorS. CHANDRASEKARAN, S. CHANDRASEKARANSearch for more papers by this authorP. SIRET, P. SIRETSearch for more papers by this authorG. E. KECK, G. E. KECKSearch for more papers by this authorJ.-L. GRAS, J.-L. GRASSearch for more papers by this author E. J. COREY, E. J. COREYSearch for more papers by this authorR. L. DANHEISER, R. L. DANHEISERSearch for more papers by this authorS. CHANDRASEKARAN, S. CHANDRASEKARANSearch for more papers by this authorP. SIRET, P. SIRETSearch for more papers by this authorG. E. KECK, G. E. KECKSearch for more papers by this authorJ.-L. GRAS, J.-L. GRASSearch for more papers by this author First published: March 20, 1979 https://doi.org/10.1002/chin.197912389Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume10, Issue12March 20, 1979 RelatedInformation

Total synthesis of gibberellic acid. A new and effective route to a key tricyclic intermediate

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTotal synthesis of gibberellic acid. A new and effective route to a key tricyclic intermediateE. J. Corey and Janice Gorzynski SmithCite this: J. Am. Chem. Soc. 1979, 101, 4, 1038–1039Publication Date (Print):February 1, 1979Publication History Published online1 May 2002Published inissue 1 February 1979https://doi.org/10.1021/ja00498a044RIGHTS & PERMISSIONSArticle Views1451Altmetric-Citations42LEARN 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 (302 KB) Get e-Alerts Get e-Alerts

Stereospecific total synthesis of gibberellic acid. A key tricyclic intermediate

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStereospecific total synthesis of gibberellic acid. A key tricyclic intermediateE. J. Corey, Rick L. Danheiser, Srinivasan Chandrasekaran, Patrice Siret, Gary E. Keck, and Jean Louis GrasCite this: J. Am. Chem. Soc. 1978, 100, 25, 8031–8034Publication Date (Print):December 1, 1978Publication History Published online1 May 2002Published inissue 1 December 1978https://doi.org/10.1021/ja00493a055RIGHTS & PERMISSIONSArticle Views4755Altmetric-Citations168LEARN 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 (599 KB) Get e-Alerts Get e-Alerts

Total Synthesis of 1,11- and 3,11-Diazasteroids

The 2- and 6-methoxy derivatives of 8-aminoquinoline, as well as 5-aminoisoquinoline, condensed with 2-ethoxycarbonylcyclopentanone to give tricyclic intermediates in 86-90% yield. These secosteroids were cyclized in 35-6s yield with polyphosphoric acid to 2-methoxy- 1,11 -diaza-, 7-methoxy- 1,11 -diaza-, and 3,II -diaza-1,3,5,7,9,13-gonahexaen-12-ones, respectively. The latter exhibits slight antileukemic activity.

Novel polycyclic heterocycles. XIV. Diels‐alder adducts of 11,12‐dihydropyrido[2,1‐b][1,3] benzodiazepine, 6H‐pyrido[1,2‐c] [1,3,5]‐ benzoxadiazepines, and 6H‐pyrido[1,2‐c] [1,3,5] benzothiadiazepine and their hydrogenation products

Journal of Heterocyclic ChemistryVolume 12, Issue 4 p. 805-807 Note Novel polycyclic heterocycles. XIV. Diels-alder adducts of 11,12-dihydropyrido[2,1-b][1,3] benzodiazepine, 6H-pyrido[1,2-c] [1,3,5]- benzoxadiazepines, and 6H-pyrido[1,2-c] [1,3,5] benzothiadiazepine and their hydrogenation products† Harry L. Yale, Corresponding Author Harry L. Yale Squibb Institute for Medical Research, Princeton, NJ 08540Squibb Institute for Medical Research, Princeton, NJ 08540Search for more papers by this authorJ. A. Bristol, J. A. Bristol Squibb Institute for Medical Research, Princeton, NJ 08540Search for more papers by this author Harry L. Yale, Corresponding Author Harry L. Yale Squibb Institute for Medical Research, Princeton, NJ 08540Squibb Institute for Medical Research, Princeton, NJ 08540Search for more papers by this authorJ. A. Bristol, J. A. Bristol Squibb Institute for Medical Research, Princeton, NJ 08540Search for more papers by this author First published: August 1975 https://doi.org/10.1002/jhet.5570120443Citations: 2 † The synthesis of the tricyclic intermediates employed in these Diels-Alder reactions has been reported previously; cf. R. B. Petigara and H. L. Yale, J. Heterocyclic Chem., 11, 331 (1974). AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume12, Issue4August 1975Pages 805-807 RelatedInformation

Mirestrol. I. Preparation of the tricyclic intermediate.

Mirestrol. I. Preparation of the tricyclic intermediate.

Studies on intramolecular alkylation. I. The preparation of tricyclic intermediates for the synthesis of diterpene alkaloids

The tricyclic dienones (14), (16), and (16) have been prepared by the Ar1-6 cyclization of a diastereomeric mixture of 7-[(2?-bromo-1?- tetrahydropyranyloxy)-ethyl]-5,6,7,8-tetrahydro-2-naphthols (11) and of 7-diazoacetyl-5,6,7,8-tetrahydro-2-naphthol (17). Intermediates (11) and (17) were prepared by standard procedures from 1,2,3,4-tetrahydro- 7-hydroxy-2-naphthoic acid.

Selective reactions and modification of functional groups in steroid chemistry

THE last ten years have seen a concentrated effort in the partial and total synthesis of steroids, occasioned in particular by the discovery of the adrenocortical hormones and of their physiological activity. This effort has involved conducting selective reactions on multifunctional compounds, and protection of one type of functional group against the consequence of reactions aimed at another. It seems desirable to give a review of such selective reactions and modifications; not only for the benefit of workers in the steroid field itself, but also as a guide for those working in other fields of organic synthesis, some of whom tend to assume that steroid chemistry is an exclusive domain. This review covers the more important literature from 1948 through 1957, but it is not intended to be exhaustive. Work on tricyclic intermediates in steroid total synthesis has been included, but facts published in communication form are not dealt with unless such communications mention a modicum of experimental detail.

Totalsynthese des Aldosterons. A. (21→4)‐Lacton der d,l‐δ8a‐1‐Oxo‐ 2α‐methallyl‐4 β‐hydroxy‐4b β‐methyl‐7‐äthylendioxy‐4a α, 10a β‐dodecahydro‐phenanthren‐2 β‐carbonsäure. Über Steroide, 147. Mitteilung

AbstractStarting from d,l‐δ8a‐1‐oxo‐4 β‐hydroxy‐4b β‐methyl‐7‐ethylene‐ dioxy‐l,2,3,4, 4a α, 4b β, 5,6,7,8,10,10a β‐dodecahydro‐phenanthrene (I) the preparation of several tricyclic intermediates substituted at carbon atom 2 is described. The structure of these compounds has been established by a series of transformations.