154422-25-0Relevant academic research and scientific papers
A highly selective Ir-catalyzed borylation of 2-substituted indoles: a new access to 2,7- and 2,4,7-substituted indoles
Lo, Wei Fun,Kaiser, Hanns Martin,Spannenberg, Anke,Beller, Matthias,Tse, Man Kin
, p. 371 - 375 (2007)
The selective CH-functionalization of 2-substituted indoles is presented. Using bis(pinacolato)diboron (2) in the presence of iridium complexes, a novel catalytic mono-borylation is observed preferentially at the 7-position of the indole. This allows for
Design and synthesis of calindol derivatives as potent and selective calcium sensing receptor agonists
Kiefer, Lionel,Beaumard, Floriane,Gorojankina, Tatiana,Faure, Hélène,Ruat, Martial,Dodd, Robert H.
, p. 554 - 569 (2016/02/09)
We report the first comprehensive structure-activity study of calindol (4, (R)-N-[(1H-indol-2-yl)methyl]-1-(1-naphthyl)ethanamine), a positive allosteric modulator, or calcimimetic, of the calcium sensing receptor (CaSR). While replacement of the naphthyl moiety of calindol by other aromatic groups (phenyl, biphenyl) was largely detrimental to calcimimetic activity, incorporation of substituents on the 4, 5 or 7 position of the indole portion of calindol was found to provide either equipotent derivatives compared to calindol (e.g., 4-phenyl, 4-hydroxy, 5-hydroxycalindol 44, 52, 53) or, in the case of 7-nitrocalindol (51), a 6-fold more active calcimimetic displaying an EC50 of 20 nM. Unlike calindol, the more active CaSR calcimimetics were shown not to act as antagonists of the closely related GPRC6A receptor, suggesting a more selective profile for these new analogues.
Indoles via Knoevenagel-Hemetsberger reaction sequence
Heaner Iv, William L.,Gelbaum, Carol S.,Gelbaum, Leslie,Pollet, Pamela,Richman, Kent W.,Dubay, William,Butler, Jeffrey D.,Wells, Gregory,Liotta, Charles L.
, p. 13232 - 13242 (2013/09/02)
A series of substituted indoles have been synthesized by the sequential reaction of aromatic aldehydes with ethyl azidoacetate in the presence of sodium ethoxide to form the corresponding ethyl α-azido-β-arylacrylates (Knoevenagel process) followed by a solvent mediated thermolysis (Hemetsberger process). The isolated yields of the ethyl α-azido-β-arylacrylates were significantly increased when employing the sacrificial electrophile ethyl trifluoroacetate. 1H NMR and coupled 1H-13C NMR analysis of the ethyl α-azido-β-arylacrylates indicate that the condensation is stereospecific - only the Z-isomer could be detected. Solvent mediated thermal treatment of the meta-substituted ethyl α-azido-β- arylacrylates resulted in the formation of both the 5- and 7- substituted indoles - the 5-regioisomer being slightly favored over the 7-regioisomer. Analogous thermal treatment of (2Z, 2Z′)-diethyl 3,3′-(1,3- phenylene)bis(2-azidoacrylate) and (2Z, 2Z′)-diethyl 3,3′-(1,4- phenylene)bis(2-azidoacrylate) exclusively produced pyrroloindoles, diethyl 1,5-dihydropyrrolo[2,3-f]indole-2,6-dicarboxylate and diethyl 1,5-dihydropyrrolo[2,3-f]indole-2,6-dicarboxylate, respectively. Results are also reported which indicate that the α-azido-β-arylacrylates can be used in the subsequent Hemetsberger indolization process without prior purification.
Fischer indolization of variously ortho-substituted phenylhydrazones (Fischer indolization and its related compounds. XXV)
Murakami,Watanabe,Yokoyama,Naomachi,Iwase,Watanabe,Morihata,Okuyama,Kamakura,Takahashi,Atoda,Tojo,Morita,Ishii
, p. 1910 - 1919 (2007/10/02)
Various kinds of ethyl pyruvate 2-(2-substituted phenyl)hydrazones (1) were subjected to Fischer indolization with acid catalysts. All the phenylhydrazones gave corresponding normal 7-substituted indoles (2). In addition, phenylhydrazones whose ortho-substituent is electron-donative or has a central atom with an unshared electron pair tended to give the 4- or 5- substituted indole (3), which was produced by migration of the ortho- substituent during cyclization, whereas those whose ortho-substituent is electron-attractive tended to give little or no such abnormal product. The kind of acid catalyst used had some effect on the yield ratio of products but not on the kind of products.
