62820-81-9Relevant academic research and scientific papers
Selective Divergent Synthesis of Indanols, Indanones, and Indenes via Acid-Mediated Cyclization of (Z)- and (E)-(2-Stilbenyl)methanols and Its Application for the Synthesis of Paucifloral F Derivatives
Jongcharoenkamol, Jira,Chuathong, Patsapon,Amako, Yuka,Kono, Masato,Poonswat, Kasam,Ruchirawat, Somsak,Ploypradith, Poonsakdi
, p. 13184 - 13210 (2018/11/02)
Starting from bromo/iodobenzaldehyde derivatives, the corresponding (Z)- and (E)-(2-stilbenyl)methanols could be prepared in 2-5 steps via Pd-catalyzed cross-coupling reactions (Sonogashira and Heck reactions) followed by aryllithium/aryl Grignard addition. For the (E)-stilbenes, subsequent acid-mediated cyclization using p-TsOH immobilized on silica (PTS-Si) at low temperatures furnished the 2,3-trans-1-indanols with complete stereocontrol at the C2-C3. Further oxidization of the alcohol provided the indanones, which are structurally related to the natural product paucifloral F. At higher temperatures, 1,2- and 2,3-disubstituted indenes could be selectively prepared in good to excellent yields. On the other hand, the (Z)-stilbenes, under similar conditions (PTS-Si), did not give the indanols; only the 1,2-disubstituted indenes could be obtained. To gain further insights into the stereochemistry at C2-C3 for the (Z)-stilbenes, hydride or azide was employed as a nucleophile; the corresponding indane products were obtained with the cis stereochemistry at the C2-C3. Thus, the (Z)- or (E)-olefin geometry of the substrate directed the stereoselective indanyl cyclization to furnish the cis or trans at the C2-C3 ring junction, respectively, while reaction conditions controlled the selectivity of the product types.
Cyclic analogue of S-benzylisothiourea that suppresses kynurenine production without inhibiting indoleamine 2,3-dioxygenase activity
Fukuda, Miwa,Sasaki, Tomomi,Hashimoto, Tomoko,Miyachi, Hiroyuki,Waki, Minoru,Asai, Akira,Takikawa, Osamu,Ohno, Osamu,Matsuno, Kenji
, p. 2846 - 2849 (2018/07/30)
Kynurenine is biosynthesised from tryptophan catalysed by indoleamine 2,3-dioxygenase (IDO). The abrogation of kynurenine production is considered a promising therapeutic target for immunological cancer treatment. In the course of our IDO inhibitor programme, formal cyclisation of the isothiourea moiety of the IDO inhibitor 1 afforded the 5-Cl-benzimidazole derivative 2b-6, which inhibited both recombinant human IDO (rhIDO) activity and cellular kynurenine production. Further derivatisation of 2b-6 provided the potent inhibitor of cellular kynurenine production 2i (IC50 = 0.34 μM), which unexpectedly exerted little effect on the enzymatic activity of rhIDO. Elucidation of the mechanism of action revealed that compound 2i suppresses IDO expression at the protein level by inhibiting STAT1 expression in IFN-γ-treated A431 cells. The kynurenine-production inhibitor 2i is expected to be a promising starting point for a novel approach to immunological cancer treatment.
Novel cyclization cascades to functionalized indanes and tetrahydronaphthalenes
Khan, Zulfiqar A.,Iwaoka, Michio,Wirth, Thomas
experimental part, p. 6639 - 6646 (2010/10/19)
Cyclization cascades involving C-C bond formations followed by lactonization reactions provide fast access to structurally complex tricyclic indane and tetrahydronaphthalene derivatives. Crown Copyright
Base-catalyzed ring openings of benzocyclobutenones and -ols
Bradley, J. C.,Durst, T.
, p. 1660 - 1665 (2007/10/02)
The base-catalyzed ring opening of a number of isomeric E- and Z-benzylidenebenzocyclobutenones and -ols has been studied in both protic and aprotic solvents.Cleavage of the C1-C2 bond results in the formation of stilbenes with mainly, and at times exclusively, retained stereochemistry.For the alcohols, these results point to an oxyanion-induced carbon-carbon bond cleavage leading to a vinyl anion that is protonated with retention of configuration in the protic solvents rather than to an electrocyclic ring opening to an alkoxy o-quinodimethane.Reaction of the Z isomer of benzylidenebenzocyclobutenol with methyllithium in THF at 20 deg C causes isomerization to the E isomer, cleavage of the C1-C2 bond, and recyclization of the resultant isomerized vinyl anion. - Key words: benzylidenebenzocyclobutenones, base-catalyzed ring opening; benzylidenebenzocyclobutenols, base-catalyzed ring opening.
1,7-Electrocyclisation and Carbene Reactions of o-Alkenylaryldiazoalkanes: The Effect of Alkene Configuration on the Mode of Reaction
Munro, David P.,Sharp, John T.
, p. 849 - 858 (2007/10/02)
The 1,7-8?-electron electrocyclisation of o-alkenylaryldiazoalkanes (1) to give 1H-2,3-benzodiazepines (3) takes place readily for substrates with a cis-hydrogen atom at the cyclisation site, but is blocked by phenyl or methyl groups at that position.Such
