18374-17-9Relevant academic research and scientific papers
Total syntheses of vincadifformine, 3-oxovincadifformine, pseudo- and 20-epi-pseudovincadifformine, tabersonine, and Δ18-tabersonine through radical reactions and heck reactions
Kuehne, Martin E.,Wang, Tiansheng,Seaton, Pamela J.
, p. 6001 - 6008 (1996)
The pentacyclic alkaloids vincadifformine (9), ψ-vincadifformine (15), and epi-ψ-vincadifformine (16) could be synthesized by intramolecular free-radical-induced cyclizations of the tetracyclic intermediates 7, 8, and 18, which were respectively obtained by condensation of the indoloazepine 1 with 2-(phenylselenyl)butyraldehyde and subsequent Nb-alkylation of the resulting tetracyclic amines 2 and 3, or from condensation of (phenylselenyl)acetaldehyde with the alkylated indoloazepine 17. The intermediates 2 and 3 also gave 3-oxovincadifformine (21) by an intermolecular radical alkylation with methyl acrylate. Their alkylation with (Z)-1,3-diiodopropene, phenyl selenoxide elimination, and intramolecular Heck reactions provided tabersonine (24) and 18,19-didehydrotabersonine (27).
Racemization of (-)-Vincadifformine using Microwave Oven
Takano, Seiichi,Kijima, Atsushi,Sugihara, Takumichi,Satoh, Shigeki,Ogasawara, Kunio
, p. 87 - 88 (1989)
Thermolysis of (-)-vincamine in DMF using a microwave oven has brought about total racemization via concurrent Diels-Alder cycloreversion and cycloaddition.
A Concise Synthesis of (+/-)-Vincadifformine and Related Aspidosperma Alkaloids (+/-)-Desethylvincadifformine, (+/-)-Ibophyllidine, (+/-)-20-Epi-ibophyllidine, and (+/-)-Desethylibophyllidine
Barsi, Marie-Christine,Das, Bhupesh C.,Fourrey, Jean-Louis,Sundaramoorthi, Rajeswari
, p. 88 - 89 (1985)
An expeditious total synthesis of (+/-)-vincadifformine (9) and related Aspidosperma alkaloids (+/-)-desethylvincadifformine (10), (+/-)-ibophyllidine (11), (+/-)-20-epi-ibophyllidine (12), and (+/-)-desethylibophyllidine (13) via condensation of a common indole-2-acrylate precursor (2) and an appropriate amine (4) followed by acidic treatment is reported.
Asymmetric Total Synthesis of Vincadifformine Enabled by a Thiourea-Phosphonium Salt Catalyzed Mannich-Type Reaction
Pan, Lu,Zheng, Chang-Wu,Fang, Guo-Sheng,Hong, Hao-Ran,Liu, Jun,Yu, Long-Hui,Zhao, Gang
, p. 6306 - 6310 (2019/04/26)
An asymmetric total synthesis of vincadifformine is described. The limited tactics with chiral cation-directed catalysis in total synthesis inspired the development of our strategy for accessing this alkaloid in enantionrich form. The route features a thiourea–phosphonium salt catalyzed Mannich-type reaction, a phosphine-promoted aza-Morita–Baylis–Hillman reaction and a trifluoroacetic acid promoted deprotection/amidation cascade process.
A unified synthesis of topologically diverse: Aspidosperma alkaloids through divergent iminium-trapping
Mijangos, Marco V.,Miranda, Luis D.
, p. 9409 - 9419 (2019/01/03)
Aspidospermidine, vincadifformine, 1,2-dehydroaspidospermidine, goniomitine, and quebrachamine, five Aspidosperma alkaloids distributed within three structurally diverse topologies, were synthesized from a single molecular scaffold, namely indole-valerolactam 6. This common intermediate can be divergently manipulated, through the incorporation of conformational and electronic constraints that influence the chemo-selectivity of the iminium ion derived therefrom, between three different reaction paths: N(1) vs. C(3) cyclization (indole numbering) vs. over-reduction. Moreover, a catalytic carbene insertion for direct C(3)-H indole functionalization is reported for the first time in an approach to goniomitine (4), and a following tandem ester reduction/iminium generation/cyclization secured its tetracyclic system. The development of a highly diastereoselective one-pot hemi-reduction/cyclization/deprotection process to obtain a cis-pyridocarbazole directly allowed the synthesis of pentacyclic Aspidosperma alkaloids 1, 2, and 3.
Divergent Asymmetric Total Synthesis of (+)-Vincadifformine, (-)-Quebrachamine, (+)-Aspidospermidine, (-)-Aspidospermine, (-)-Pyrifolidine, and Related Natural Products
Wang, Nengzhong,Du, Shuo,Li, Dong,Jiang, Xuefeng
supporting information, p. 3167 - 3170 (2017/06/23)
A uniformly strategic total synthesis of Aspidosperma alkaloids (+)-vincadifformine, (-)-quebrachamine, (+)-aspidospermidine, (-)-aspidospermine, (-)-pyrifolidine, and nine others from efficiently constructed tricyclic ketone 13 is reported. Highlights of these divergent and practical syntheses include (i) stereoselective intermolecular [4 + 2] cycloaddition to establish a C-E ring with one all-carbon quaternary stereocenter (C-5) and two bridged contiguous cis-stereocenters (C-12 and C-19), (ii) a Pd/C-catalyzed hydrogenation/deprotection/amidation cascade process to assemble the D ring, and (iii) Fischer indolization to forge the A-B ring.
Expeditious and Divergent Total Syntheses of Aspidosperma Alkaloids Exploiting Iridium(I)-Catalyzed Generation of Reactive Enamine Intermediates
Tan, Peng Wen,Seayad, Jayasree,Dixon, Darren J.
, p. 13436 - 13440 (2016/10/21)
A new approach for the divergent total syntheses of (±)-vincaminorine, (±)-N-methylquebrachamine, (±)-quebrachamine, (±)-minovine and (±)-vincadifformine, each in less than 10 linear steps starting from a single δ-lactam building block, is reported. Key to our route design is the late-stage generation of reactive enamine functionality from stable indole-linked δ-lactams via a highly chemoselective iridium(I)-catalyzed reduction. The efficiently formed secodine intermediates subsequently undergo either a formal Diels–Alder cycloaddition or a competitive Michael addition/reduction to access aspidosperma-type alkaloids in excellent diastereoselectivities. Product selectivity could be controlled by changing the indole N-protecting group in the reductive cyclization precursors. An asymmetric variant of this synthetic strategy for the synthesis of (+)-20-epi-ibophyllidine is also described.
Formal total syntheses of classic natural product target molecules via palladium-catalyzed enantioselective alkylation
Liu, Yiyang,Liniger, Marc,McFadden, Ryan M.,Roizen, Jenny L.,Malette, Jacquie,Reeves, Corey M.,Behenna, Douglas C.,Seto, Masaki,Kim, Jimin,Mohr, Justin T.,Virgil, Scott C.,Stoltz, Brian M.
, p. 2501 - 2512 (2015/02/19)
Pd-catalyzed enantioselective alkylation in conjunction with further synthetic elaboration enables the formal total syntheses of a number of "classic" natural product target molecules. This publication highlights recent methods for setting quaternary and tetrasubstituted tertiary carbon stereocenters to address the synthetic hurdles encountered over many decades across multiple compound classes spanning carbohydrate derivatives, terpenes, and alkaloids. These enantioselective methods will impact both academic and industrial settings, where the synthesis of stereogenic quaternary carbons is a continuing challenge.
Unified strategy to monoterpene indole alkaloids: Total syntheses of (±)-Goniomitine, (±)-1,2-Dehydroaspidospermidine, (±)-Aspidospermidine, (±)-Vincadifformine, and (±)-Kopsihainanine A
Wagnires, Olivier,Xu, Zhengren,Wang, Qian,Zhu, Jieping
supporting information, p. 15102 - 15108 (2014/12/11)
Total syntheses of (±)-goniomitine, (±)-1,2-dehydroaspidospermidine, (±)-aspidospermidine, (±)-vincadifformine, and (±)-kopsihainanine A were achieved featuring two common key steps: (1) a palladium-catalyzed decarboxylative vinylation that provides quick access to cyclopentene intermediates containing all of the carbons present in the natural products and (2) an integrated oxidation/reduction/cyclization (iORC) sequence for skeletal reorganization that converts the cyclopentenes to the pentacyclic structures of the natural products. By incorporation of a geometric constraint to iORC substrates, both the chemoselectivity (C7 vs N1 cyclization) and the stereoselectivity (trans- vs cis-fused ring system) of the cyclization process can be controlled.
Biogenetically inspired synthesis and skeletal diversification of indole alkaloids
Mizoguchi, Haruki,Oikawa, Hideaki,Oguri, Hiroki
, p. 57 - 64 (2014/01/17)
To access architecturally complex natural products, chemists usually devise a customized synthetic strategy for constructing a single target skeleton. In contrast, biosynthetic assembly lines often employ divergent intramolecular cyclizations of a polyunsaturated common intermediate to produce diverse arrays of scaffolds. With the aim of integrating such biogenetic strategies, we show the development of an artificial divergent assembly line generating unprecedented numbers of scaffold variations of terpenoid indole alkaloids. This approach not only allows practical access to multipotent intermediates, but also enables systematic diversification of skeletal, stereochemical and functional group properties without structural simplification of naturally occurring alkaloids. Three distinct modes of [4+2] cyclizations and two types of redox-mediated annulations provided divergent access to five skeletally distinct scaffolds involving iboga-, aspidosperma-, andranginine- and ngouniensine-type skeletons and a non-natural variant within six to nine steps from tryptamine. The efficiency of our approach was demonstrated by successful total syntheses of (±)-vincadifformine, (±)-andranginine and (-)-catharanthine.
