The extraction of the stinging nettle leaves was performed with 20 kg/h flow rate of supercritical CO2. The influence of the working parameters: pressure (140 bar, 210 bar and 350 bar), temperature (from 40 oC to 60 oC) on the quantity of extract and contents of chlorophyll a+b and b-carotene in it is determined. The biggest quantity of extract (4.48% in relation to the dry matter) with 0.88% contents of chlorophyll a+b and 0.50% b-carotene is obtained at 350 bar, 60 oC, 6h extraction time.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCarbon-13 nuclear magnetic resonance: aconitine-type diterpenoid alkaloids from Aconitum and Delphinium speciesS. W. Pelletier and Z. DjarmatiCite this: J. Am. Chem. Soc. 1976, 98, 9, 2626–2636Publication Date (Print):April 1, 1976Publication History Published online1 May 2002Published inissue 1 April 1976https://pubs.acs.org/doi/10.1021/ja00425a036https://doi.org/10.1021/ja00425a036research-articleACS PublicationsRequest reuse permissionsArticle Views952Altmetric-Citations86LEARN 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 InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

AbstractZwischen den 13 C‐chemischen Verschiebungen des Carbinyl‐CU) von 28 untersuchten Estern und den pKa‐Werten der zugrunde liegenden Carbonsäuren R‐COOH (mit R: ‐CH3, ‐CMe3, ‐Ph, p‐NO, ‐C6H4 , ‐CH2Cl, ‐CHCI2 , ‐CC13) existiert eine lineare Beziehung.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAlkaloids of Delphinium staphisagria. The structure and stereochemistry of delphisine, neoline, chasmanine, and homochasmanineS. W. Pelletier, Z. Djarmati, S. Lajsic, and Wilson H. De CampCite this: J. Am. Chem. Soc. 1976, 98, 9, 2617–2625Publication Date (Print):April 1, 1976Publication History Published online1 May 2002Published inissue 1 April 1976https://pubs.acs.org/doi/10.1021/ja00425a035https://doi.org/10.1021/ja00425a035research-articleACS PublicationsRequest reuse permissionsArticle Views276Altmetric-Citations38LEARN 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 InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCarbon-13 nuclear magnetic resonance spectroscopy of polycyclic .delta.-lactonesMiroslav J. Gasic, Zoltan Djarmati, and S. William PelletierCite this: J. Org. Chem. 1976, 41, 7, 1219–1221Publication Date (Print):April 1, 1976Publication History Published online1 May 2002Published inissue 1 April 1976https://pubs.acs.org/doi/10.1021/jo00869a029https://doi.org/10.1021/jo00869a029research-articleACS PublicationsRequest reuse permissionsArticle Views74Altmetric-Citations19LEARN 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 InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The diterpene alkaloid chasmanine, previously reported to have a 1β-methoxy-substituent, has been shown to have a 1α-methoxy-group by X-ray crystallography; it is shown that the reported chemical correlation between browniine and chasmanine is in error.

AbstractAnhand der Röntgen‐ Spektralanalyse, NMR‐Spektren (Abbildung) und chemischer Untersuchungen werden für Delphisin (Ia) die absolute Konfiguration 1S, 4S, 5R, 6R, 7R, 8R, 9R, IOR, 11S, 13R, 14S, 16S, 17R, die Wannenform für den Ring A, sowie die Zugehörigkeit zu dem Typ der Aconitin‐Alkaloide ermittelt.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe structures of staphigine and staphirine. Two novel bisditerpene alkaloids from Delphinium staphisagriaS. William Pelletier, Naresh V. Mody, Zoltan Djarmati, and Stevan D. LajsicCite this: J. Org. Chem. 1976, 41, 18, 3042–3044Publication Date (Print):September 1, 1976Publication History Published online1 May 2002Published inissue 1 September 1976https://pubs.acs.org/doi/10.1021/jo00880a032https://doi.org/10.1021/jo00880a032research-articleACS PublicationsRequest reuse permissionsArticle Views110Altmetric-Citations14LEARN 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 InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The 13C chemical shifts of the 28 carboxylic esters have been determined by high-resolution NMR spectroscopy with the aid of proton decoupling. A linear relationship is shown to exist between the 13C chemical shifts of the carbinyl carbon (C-1) of the esters and the pKa values of the acids from which they are derived. This is a consequent of the polar character of the bond. Similarly, if the carboxyl group is kept constant, but the alcoholic part of the ester is varied from primary to secondary and tertiary alcohols, the esterification effect on C-1 can be correlated with the increasing stability of the +δ charge on the carbinyl carbon. The smallest esterification effect at C-1 (1.3 ppm, relative to the parent alcohol) is observed for methyl pivalate (pKa 5.03 for the parent acid), and the highest effect (17.7 ppm) for 2-methyl-2-propyl trichloroacetate (pKa 0.70). In contrast, the C-2 esterification effect has been found to be essentially constant (−3.8±0.7 ppm), which is in agreement only with a conformation of the ester group in which the carbinyl carbon is cis with respect to the CO group.

Chemischer InformationsdienstVolume 6, Issue 8 Natural Products ChemInform Abstract: STRUCTURE OF NEOLINE, CHASMANINE, AND HOMOCHASMANINE S. W. PELLETIER, S. W. PELLETIERSearch for more papers by this authorZ. DJARMATI, Z. DJARMATISearch for more papers by this authorS. D. LAJSIC, S. D. LAJSICSearch for more papers by this author S. W. PELLETIER, S. W. PELLETIERSearch for more papers by this authorZ. DJARMATI, Z. DJARMATISearch for more papers by this authorS. D. LAJSIC, S. D. LAJSICSearch for more papers by this author First published: February 25, 1975 https://doi.org/10.1002/chin.197508469AboutPDF 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 onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume6, Issue8February 25, 1975 RelatedInformation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNaturally occurring terpenes. Synthesis of (+)- and (+-)-14,15-bisnor-8.alpha.-hydroxylabd-11(E)-en-13-one, (+)-drimane-8,11-diol, and (-)-drimenolS. William Pelletier, Stevan Lajsic, Yasuo Ohtsuka, and Zoltan DjarmatiCite this: J. Org. Chem. 1975, 40, 11, 1607–1609Publication Date (Print):May 1, 1975Publication History Published online1 May 2002Published inissue 1 May 1975https://pubs.acs.org/doi/10.1021/jo00899a019https://doi.org/10.1021/jo00899a019research-articleACS PublicationsRequest reuse permissionsArticle Views232Altmetric-Citations30LEARN 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 InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The cycloaddition of diazoalkanes, diazoesters and diazoketones to 2(5H)-furanones followed by thermal decomposition of the respective adducts is shown to provide a general method for the preparation of a variety of alkylated 2(5H)-furanones. Reduction of the latter compounds with diisobutylaluminum hydride affords the corresponding substituted furans in good yield.

AbstractDie Furanone (I) addieren die Diazoalkane (II) unter praktisch quantitativer Bildung der Pyrazolincarbonsäurelactone (III), die beim Erhitzen in Dioxan in die Furanone (IV) übergehen.

Chemischer InformationsdienstVolume 6, Issue 8 Physical Organic Chemistry ChemInform Abstract: STRUCTURE AND ABSOLUTE CONFIGURATION OF DELPHISINE, A NEW DITERPENE ALKALOID FROM DELPHINIUM STAPHISAGRIA S. W. PELLETIER, S. W. PELLETIERSearch for more papers by this authorW. H. DE CAMP, W. H. DE CAMPSearch for more papers by this authorS. D. LAJSIC, S. D. LAJSICSearch for more papers by this authorZ. DJARMATI, Z. DJARMATISearch for more papers by this authorA. H. KAPADI, A. H. KAPADISearch for more papers by this author S. W. PELLETIER, S. W. PELLETIERSearch for more papers by this authorW. H. DE CAMP, W. H. DE CAMPSearch for more papers by this authorS. D. LAJSIC, S. D. LAJSICSearch for more papers by this authorZ. DJARMATI, Z. DJARMATISearch for more papers by this authorA. H. KAPADI, A. H. KAPADISearch for more papers by this author First published: February 25, 1975 https://doi.org/10.1002/chin.197508098AboutPDF 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 onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume6, Issue8February 25, 1975 RelatedInformation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of neoline, chasmanine, and homochasmanineS. W. Pelletier, Z. Djarmati, and S. LajsicCite this: J. Am. Chem. Soc. 1974, 96, 25, 7817–7818Publication Date (Print):December 1, 1974Publication History Published online1 May 2002Published inissue 1 December 1974https://pubs.acs.org/doi/10.1021/ja00832a038https://doi.org/10.1021/ja00832a038research-articleACS PublicationsRequest reuse permissionsArticle Views143Altmetric-Citations14LEARN 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 InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts