104069-12-7Relevant articles and documents
Photocatalytic Cascade Radical Cyclization Approach to Bioactive Indoline-Alkaloids over Donor-Acceptor Type Conjugated Microporous Polymer
Ou, Wei,Zhang, Guoqiang,Wu, Jie,Su, Chenliang
, p. 5178 - 5183 (2019)
Herein, we describe a visible-light-induced radical strategy for the 1,2-formylarylation of N-arylacrylamides via the C-H activation of 1,3-dioxolane using a carbazolic-cyano conjugated microporous polymer (CC-CMP) as a metal-free photocatalyst. This process provides an efficient and mild approach for constructing highly functionalized formyl-substituted oxindoles, which are valuable building blocks that allow rapid access to various important heterocycle-fused and spirocyclic indole alkaloids. Utilizing this strategy, bioactive alkaloids, such as (±)-desoxyeseroline, (±)-esermethole, and (±)-N-Me-coerulescine, have been concisely synthesized in up to 74% overall yield from low-cost acrylamides and 1,3-dioxolane. The overall yields of our approach are much higher than those of conventional multistep methods. Gram-scale syntheses of natural alkaloids have been demonstrated, highlighting the practical utility of this protocol. The use of CC-CMP photocatalysts, which are metal-free, flexible, stable, effective, and reusable, making this strategy appealing to advanced chemical manufacturing.
Total Synthesis of (±)-Phenserine via [4+1] Cyclization of a Bis(alkylthio)carbene and an Indole Isocyanate
Rigby, James H.,Sidique, Shyama
, p. 1219 - 1221 (2007)
Figure presented A total synthesis of acetylcholine blocking agent, phenserine, has been achieved by employing a [4+1] cyclization between an appropriately substituted indole isocyanate and a bis(alkylthio)carbene.
An efficient synthesis of optically active physostigmine from tryptophan via alkylative cyclization
Kawahara, Michiaki,Nishida, Atsushi,Nakagawa, Masako
, p. 675 - 678 (2000)
(Equation Presented) Physostigmine A new and efficient synthetic route to physostigmine is described. Corey-Kim reagent reacted with tryptamine or tryptophan carbamates to give 3a-(methylthiomethyl)hexahydropyrrolo[2,3-b]indole skeletons. Formal total synthesis of racemic and chiral physostigmine was accomplished in excellent overall yields, in short steps.
The photocatalysis synthetic alkaloid (by machine translation)
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Paragraph 0126; 0127; 0128, (2018/11/22)
The present invention provides a catalytic synthesis method of living beings, the alkaloid comprises indole fused ring class and indole spiro compound, the process is as follows: in order to nitrogen aryl acrylamide as raw materials in under the photocatalysis with peroxide synthesis 3 - acetal 2 - indole compound, obtained through hydrolysis 3 - formyl - 2 - indole compound, further reducing synthetic alkaloid, the method routes mild, efficiency is high-efficient. The reaction in the illumination can occur under the room temperature, mild condition, has better substrate versatility and functional group tolerant. (by machine translation)
Pd(0)-Catalyzed Chemoselective Deacylative Alkylations (DaA) of N-Acyl 2-Oxindoles: Total Syntheses of Pyrrolidino[2,3- b]indoline Alkaloids, (±)-Deoxyeseroline, and (±)-Esermethole
Kumar, Nivesh,Gavit, Vipin R.,Maity, Arindam,Bisai, Alakesh
, p. 10709 - 10735 (2018/09/29)
We report an efficient Pd(0)-catalyzed deacylative allylation of N-acyl 3-substituted 2-oxindoles via the coupling of in situ generated nucleophiles (3 and 4) with allyl electrophiles for the synthesis of a variety of 2-oxindoles with C3-quaternary centers. Gratifyingly, this alkylation process is found to be highly chemoselective in nature, where a C-C bond formation is completely predominant over a C-N bond formation. A variety of key intermediates were synthesized utilizing an aforementioned methodology.
Metal-Free Synthesis of Oxazolidine-2,4-diones and 3,3-Disubstituted Oxindoles via ICl-Induced Cyclization
Yi, Wei,Fang, Xing-Xiao,Liu, Qing-Yun,Liu, Gong-Qing
, p. 6671 - 6681 (2019/01/04)
A metal-free method for the construction of oxazolidine-2,4-diones and oxindoles was discussed. Using iodine monochloride (ICl) as both the reaction promoter and iodide source, the iodolactonization of N-Boc acrylamides proceeded readily and provided the corresponding iodo oxazolidine-2,4-diones and oxazolidin-2-ones in good isolated yields. The obtained oxazolidine-2,4-diones can be used as key intermediates in the synthesis of toloxatone. When N-alkyl-N-arylacrylamide derivatives were subjected to the same reaction, iodocarbocyclization products 3,3-disubstituted oxindoles were obtained. The obtained oxindoles can be used as key intermediates in the synthesis of the alkaloids (±)-esermethole and (±)-physostigmine.
Synthesis of C3-Methyl-Substituted Pyrroloindolines and Furoindolines via Cascade Dearomatization of Indole Derivatives with Methyl Iodide
Yi, Ji-Cheng,Liu, Chuan,Dai, Li-Xin,You, Shu-Li
supporting information, p. 2975 - 2979 (2017/11/14)
A highly efficient method for constructing C3-methyl-substituted pyrroloindolines and furoindolines via cascade dearomatization reaction of indole derivatives with methyl iodide was developed. This protocol offers a direct approach to a wide range of C3 methyl substituted pyrroloindolines under mild conditions. The utility of this method was further demonstrated in the concise synthesis of (±)-esermethol.
Preparation method for physostigmine precursor compound
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Paragraph 0013; 0048-0051, (2017/09/13)
The invention relates to physostigmine and provides a preparation method for a physostigmine precursor compound. The physostigmine precursor compound is prepared with 5-methoxytryptamine as a starting raw material through amino protection, intramolecular cyclization, methylation and amide reduction. The preparation method has the advantages of simple synthesis route, usage of cheap and easily available synthesis reagents, simple synthesis operation, friendliness to environment and the like and is highly feasible in industrial production. In particular, a cyclization reagent, i.e., 1,3-dichloro-5,5-dimethylhydantoin, used in the key intramolecular cyclization is a commercial germicide and disinfectant and is cheap, easily available and friendly to environment. The physostigmine precursor compound used as a synthesis precursor or intermediate for physostigmine is also applicable as a synthesis precursor for phenserine and a variety of physostigmine derivatives and thus has good application value and development potential.
FeCl3-Catalyzed Allylation Reactions onto 3-Hydroxy-2-oxindoles: Formal Total Syntheses of Bis-cyclotryptamine Alkaloids, (±)-Chimonanthine, and (±)-Folicanthine
Kinthada, Lakshmana K.,Medisetty, Sai Raghavendra,Parida, Amarchand,Babu, K. Naresh,Bisai, Alakesh
, p. 8548 - 8567 (2017/08/23)
An FeCl3-catalyzed efficient strategy for the allylation reactions of 3-hydroxy-2-oxindoles with allyltrimethylsilane has been developed. The reaction affords a variety of 2-oxindoles having quaternary center at the pseudobenzylic position in an operationally simple and inexpensive procedure. Control experiments using enantioenriched 3-hydroxy-2-oxindole show that the reaction proceeds through in situ generated 2H-indol-2-one (8). The methodology presents an efficient and concise access to the pyrroloindoline alkaloids (±)-deoxyeseroline (1a), (±)-esermethole (1b), (±)-physostigmine (1c), (±)-phenserine (1d), and (±)-physovenine (1e). Eventually, we extrapolated the scope of this methodology to the formal total syntheses of dimeric cyclotyrptamine alkaloids (±)-chimonanthine (3a), (±)-folicanthine (3c), and (±)-calycanthine (4).
Tert-Butyl Iodide Mediated Reductive Fischer Indolization of Conjugated Hydrazones
Ito, Yuta,Ueda, Masafumi,Takeda, Norihiko,Miyata, Okiko
supporting information, p. 2616 - 2619 (2016/02/26)
A novel reductive Fischer indolization of readily available N-aryl conjugated hydrazones with tert-butyl iodide has been developed. In this reaction, tert-butyl iodide is used as anhydrous HI source, and the generated HI acts as a Br?nsted acid and a reducing agent. This operationally simple method allows access to various indole derivatives. Furthermore, the procedure can be applied to the synthesis of biologically active compounds.
