26503-67-3Relevant academic research and scientific papers
A Gold(I)-Catalyzed Hydroamination/Cycloisomerization Cascade: Concise Synthesis of (±)-seco-Antofine and (±)-Septicine
Tian, Guilong,Song, Liangliang,Li, Zhenghua,Robeyns, Koen,Van Meervelt, Luc,Van Der Eycken, Erik V.
, p. 8441 - 8445 (2020)
A concise and flexible procedure for the synthesis of highly functionalized N-heterocyclic 1,6-annulated 2-pyridones and 2,3-annulated 4-pyrimidinones has been elaborated through a gold-catalyzed tandem hydroamination/cycloisomerization cascade. This novel and highly efficient method allows the rapid construction of these diverse N-heterocyclic scaffolds starting from readily available building blocks, and shows a wide scope and good functional group tolerance. The total synthesis of (±)-seco-antofine and (±)-septicine were realized employing this strategy.
Total Synthesis of Indolizidine Alkaloids via Nickel-Catalyzed (4 + 2) Cyclization
Renner, Jonas,Thakur, Ashish,Rutz, Philipp M.,Cowley, Jacob M.,Evangelista, Judah L.,Kumar, Puneet,Prater, Matthew B.,Stolley, Ryan M.,Louie, Janis
, p. 924 - 928 (2020/02/04)
A Ni-catalyzed (4 + 2) cycloaddition of alkynes and azetidinones toward piperidinones was used as key reaction in the enantioselective synthesis of naturally occurring indolizidine alkaloids. The reaction benefits from the use of an easily accessible azet
Formal Synthesis of Indolizidine and Quinolizidine Alkaloids from Vinyl Cyclic Carbonates
Cristòfol, àlex,B?hmer, Christian,Kleij, Arjan W.
, p. 15055 - 15058 (2019/11/16)
Cyclic carbonates have long been considered relatively inert molecules acting as protecting groups in complex multistep synthetic routes. This study shows that a concise, yet modular synthesis of indolizidine and quinolizidine alkaloids can be developed from vinyl-substituted cyclic carbonate (VCC) intermediates. Through a highly stereoselective palladium-catalyzed allylic alkylation reaction, these alkaloid motifs can be assembled in four synthetic and only two column purification steps. The combined results help to further advance functionalized cyclic carbonates as useful and reactive intermediates in natural product synthesis.
A General Cp*CoIII-Catalyzed Intramolecular C?H Activation Approach for the Efficient Total Syntheses of Aromathecin, Protoberberine, and Tylophora Alkaloids
Lerchen, Andreas,Knecht, Tobias,Koy, Maximilian,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 12149 - 12152 (2017/09/13)
Herein, we report a Cp*CoIII-catalyzed C?H activation approach as the key step to create highly valuable isoquinolones and pyridones as building blocks that can readily be applied in the total syntheses of a variety of aromathecin, protoberberine, and tylophora alkaloids. This particular C?H activation/annulation reaction was achieved with several terminal as well as internal alkyne coupling partners delivering a broad scope with excellent functional group tolerance. The synthetic applicability of this protocol reported herein was demonstrated in the total syntheses of two Topo-I-Inhibitors and two 8-oxyprotoberberine cores that can be further elaborated into the tetrahydroprotoberberine and the protoberberine alkaloid core. Moreover these building blocks were also transformed to six different tylophora alkaloids in expedient fashion.
Cyano Group Removal from Cyano-Promoted Aza-Diels-Alder Adducts: Synthesis and Structure-Activity Relationship of Phenanthroindolizidines and Phenanthroquinolizidines
Chang, Chi-Fen,Li, Chien-Fu,Tsai, Chia-Chen,Chuang, Ta-Hsien
supporting information, p. 638 - 641 (2016/03/01)
Phenanthroindolizidines and phenanthroquinolizidines were concisely synthesized by the reductive decyanization of cyano-promoted intramolecular aza-Diels-Alder cycloadducts followed by aryl-aryl coupling. Cyano groups were removed from α-aminoacrylonitriles via treatment with sodium borohydride in 2-propanol in almost quantitative yields; a possible mechanism was proposed and examined using D-labeling experiments. A systematic study of the effects of the phenanthrene substitution pattern on the anticancer activity against three human cancer cell lines was discussed. (Chemical Equation Presented).
Iminium ion-enamine cascade cyclizations: Facile access to structurally diverse azacyclic compounds and natural products
Hanessian, Stephen,Chattopadhyay, Amit Kumar
, p. 232 - 235 (2014/01/23)
A one-pot, mild, two-component iminium ion-enamine cascade reaction to construct structurally diverse azacyclic frameworks from l-proline and l-pipecolic acid, and its application to indolizidine and quinolizidine alkaloids and azasteroids, is reported.
Synthesis of (+)-septicine using intramolecular McMurry coupling: A Chiron approach
Reddy, K. Umamaheshwar,Reddy, A. Panasa
, p. 2678 - 2684 (2013/07/26)
Total synthesis of secophenanthroindolizidine alkaloid (+)-septicine 1 was accomplished using the McMurry coupling for the construction of indolizidine ring, using L-glutamicacid as chiral source. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications to view the free supplemental file.
Rhodium(III)-catalyzed intramolecular annulation through C-H activation: Total synthesis of (±)-antofine, (±)-septicine, (±)-tylophorine, and rosettacin
Xu, Xianxiu,Liu, Yu,Park, Cheol-Min
supporting information, p. 9372 - 9376 (2012/10/29)
Annulation: The efficient synthesis of 3-hydroxyalkyl isoquinolones and 6-hydroxyalkyl 2-pyridones is enabled through the intramolecular annulation of alkyne-tethered hydroxamic esters (see scheme, Cp= pentamethylcyclopentadienyl). The reaction features high regioselectivity, broad substrate scope, and excellent functional-group tolerance, proceeds under mild reaction conditions with low catalyst loading, and obviates the need for an external oxidant.
Novel 6,7-diphenyl-2,3,8,8a-tetrahydro-1H-indolizin-5-one analogues as cytotoxic agents
Sharma, Vedula M.,Adi Seshu,Vamsee Krishna,Prasanna,Chandra Sekhar,Venkateswarlu,Rajagopal, Sriram,Ajaykumar,Deevi, Dhanvanthri S.,Rao Mamidi,Rajagopalan
, p. 1679 - 1682 (2007/10/03)
A series of 6,7-diphenyl-2,3,8,8a-tetrahydro-1H-indolizin-5-one analogues were synthesized and evaluated for cytotoxic activity against eight human cancer cell lines. Compounds 18, 21, 28, 29, 30 and 31 showed cytotoxic activity with GI50 value
A unified strategy for the synthesis of phenanthroizidine alkaloids: Preparation of sterically congested pyridines
Ciufolini, Marco A.,Roschangar, Frank
, p. 12082 - 12089 (2007/10/03)
Total syntheses of the representative phenanthroizidine alkaloids, tylophorine and antofine, and of their seco congeners, septicine and julandine, have been completed from sterically congested 3,4-diarylpyridines prepared by a modified Knoevenagel-Stobbe
