Indolizidine 167B Research Articles

Chemoenzymatic Enantioselective Synthesis of (-)-Indolizidine 167B

Chemoenzymatic Enantioselective Synthesis of (-)-Indolizidine 167B

ChemInform Abstract: Stereoselective Synthesis of (.+‐.)‐Indolizidines 167B and 209D and Their trans‐Isomers Based on the Reductive Allylboration of Pyridine.

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.

ChemInform Abstract: Synthesis of Enantiopure Indolizidine Alkaloids from α‐Amino Acids: Total Synthesis of (‐)‐Indolizidine 167B.

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.

A new diastereoselective route to 5-substituted-8-methylindolizidines. Synthesis of indolizidine (−) 209B

The highly diastereoselective synthesis of the indolizidine alkaloid (−) 209B is described via the diastereoselective alkylation of a chiral cyclic β-amino ester prepared from ( R)-methylbenzylamine.

Stereoselective synthesis of (±)-indolizidines 167B and 209D and theirtrans-isomers based on the reductive allylboration of pyridine

A general method for the synthesis of 5-substituted indolizidines based on intramolecular cyclization oftrans- andcis-2-allyl-6-R-1,2,3,6-tetrahydropyridines, obtained from pyridine and triallylborane, has been elaborated. The closure of the five-membered ring is carried out by hydroboration-oxidation followed by cyclization of the resulting δ-amino alcohols in the presence of the Ph3P−CBr4−Et3N system. (Pr2BH)2 and Pr3B are used as the hydroborating reagents, and H2O2 in an acid medium is used for the oxidation of 2-[3-(dipropylboryl]-Δ2-piperideines formed. This method has been used for the synthesis of two natural alkaloids: indolizidine 209D (cis-5-hexylindolizidine) and itstrans-isomer were prepared fromcis- andtrans-2-allyl-6-hexyl-1,2,3,6-tetrahydropiridine, respectively; indolizidine 167B andtrans-5-propylindolizidine were synthesized fromcis- andtrans-2,6-diallyl-1,2,3,6-tetra-hydropyridine, respectively.

ChemInform Abstract: Total Synthesis of (.+‐.)‐Monomorine I and (.+‐.)‐Indolizidine 195B by an Aza‐[2,3]‐Wittig Rearrangement of a Vinylaziridine.

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.

Synthesis of Enantiopure Indolizidine Alkaloids from α-Amino Acids: Total Synthesis of (−)-Indolizidine 167B

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTSynthesis of Enantiopure Indolizidine Alkaloids from α-Amino Acids: Total Synthesis of (−)-Indolizidine 167BSteven R. Angle and Robert M. HenryView Author Information Department of Chemistry, University of California-Riverside, Riverside, California 92521-0403 Cite this: J. Org. Chem. 1997, 62, 24, 8549–8552Publication Date (Web):November 28, 1997Publication History Received1 April 1997Published online28 November 1997Published inissue 1 November 1997https://doi.org/10.1021/jo970591kCopyright © 1997 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views946Altmetric-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 Read OnlinePDF (181 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Amines,Chemical synthesis,Lactones,Organic compounds,Organic synthesis Get e-Alerts

Highly stereoselective construction of trans(2,3)-cis(2,6)-trisubstituted piperidines: An application to the chiral synthesis of Dendrobates alkaloids

Abstract A general and flexible route to the 5,8-disubstituted indolizidine and 1,4-disubstituted quinolizidine system found in Dendrobates alkaloids has been developed. The key step for this synthesis is the highly stereoselective Michael reaction of a didehydropiperidinecarboxylate ( 1 ) to afford a trans (2,3)- cis (2,6)-trisubstituted piperidine. In this manner, the chiral formal synthesis of indolizidines 207A and 209B and the total synthesis of indolizidines 223J, 235B' and Cl-epimer of quinolizidine 207I have been achieved.

Total synthesis of (+/-)-monomorine I and (+/-)-indolizidine 195B by an aza-[2,3]-Wittig rearrangement of a vinylaziridine.

A novel synthesis of (+/-)-monomorine I (1) and (+/-)-indolizidine 195B (2) is described in which the key step is the highly efficient aza-[2,3]-Wittig rearrangement of vinylaziridine 12 into tetrahydropyridine 13. Functional group manipulation then gave ketone 16 which could be converted into the target alkaloids by reductive amination (1:2 1.5:1).

Synthesis of (±)-Indolizidine 209B and a New 209B Diastereoisomer

Synthesis of (±)-Indolizidine 209B and a New 209B Diastereoisomer

ChemInform Abstract: Radical Cyclization of β‐Aminoacrylates: Stereoselective Synthesis of Indolizidines 167B and 209D.

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.

Radical cyclization of β-aminoacrylates: Stereoselective synthesis of indolizidines 167B and 209D

Indolizidine alkaloids 167B and 209D were synthesized via radical cyclization of β-aminoacrylates.

ChemInform Abstract: Short, Enantiospecific Syntheses of Indolizidines 209B and 209D, and Piclavine A from Diethyl‐L‐glutamate.

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.

Short, Enantiospecific Syntheses of Indolizidines 209B and 209D, and Piclavine A from Diethyl‐L‐Glutamate

AbstractThe 1H‐pyrrole derivative obtained from diethyl L‐glutamate hydrochloride and tetrahydro‐2,5‐dimethoxyfuran was cyclized with BBr3 to ethyl (5S)‐5,6,7,8‐tetrahydro‐8‐oxoindolizine‐5‐carboxylate (18). Catalytic hydrogenation of 18 over Pd/C in AcOH gave ethyl (5S,8aR)‐octahydroindolizine‐5‐carboxylate (21), whereas hydrogenation over Rh/Al2O3 in EtOH/AcOH 99:1 afforded mainly ethyl (5S,8S,8aS)‐octahydro‐8‐hydroxyindolizine‐5‐carboxylate (22). By functional‐group interconversions, 21 was transformed into piclavine A (1) and indolizidine 209D (2). Similarly, (5R,8R,8aS)‐octahydro‐5‐pentylindolizine‐8‐methanol (37), the final relay for indolizidine 209B (3), was obtained from 22.

Enantioselective total synthesis of (−)-indolizidines 209B and 209D via a highly efficient aza-[2,3]-wittig rearrangement of vinylaziridines

A novel protocol for the enantioselective synthesis of (−)-indolizidines 209B ( 2) and 209D ( 1) is described, in which the key step is the highly efficient aza-[2,3]-Wittig rearrangement of vinylaziridines 11a,b into tetrahydropyridines 12a,b. Functional group manipulation and chain elongation then gave esters 16a,b which were converted to the target alkaloids via lactams 17a,b.

Asymmetric Synthesis of Indolizidines 167B and 223AB

Asymmetric Synthesis of Indolizidines 167B and 223AB

Asymmetric Synthesis of the Indolizidine Alkaloids 207A, 209B, and 235B': 6-Substituted 2,3-Didehydropiperidine-2-carboxylate as a Versatile Chiral Building Block

The asymmetric synthesis of 5-substituted 8-methylindolizidines 1-3 was achieved via the highly stereocontrolled Michael reaction of the title compound 5

An Enantioselective Synthesis of (+)-Indolizidine 195B

A versatile enantioselective synthesis of the dendrobatid alkaloid (+)-indolizidine 195B is described, starting from the readily available lactol (1)

ChemInform Abstract: Application of the Intramolecular Schmidt Reaction to the Asymmetric Synthesis of (‐)‐Indolizidine 209B from Pulegone.

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.

An Asymmetric Synthesis of (+)-Indolizidine 195B

An asymmetric synthesis of (+)-indolizidine 195B (3-butyl-5-methylindolizidine (1) ) starting from the known pyrrolidino alcohol (1-benzyloxycarbonyl-2-butyl-5-(hydroxymethyl)pyrrolidine (2) ) available from L-norleucine has been achieved