467-55-0Relevant articles and documents
Steroidal saponins from the underground parts of Hosta longipes and their inhibitory activity on tumor promoter-induced phospholipid metabolism
Mimaki,Kanmoto,Kuroda,Sashida,Nishino,Satomi,Nishino
, p. 1190 - 1196 (1995)
Phytochemical study on the underground parts of Hosta longipes gave six new steroidal saponins together with a known one. The structures of the new compounds were determined by detailed analysis of their 1H- and 13C-NMR spectra including two-dimensional NMR spectroscopy, acid-catalyzed hydrolysis followed by chemical correlation, and by comparison with spectral data of known compounds. The isolated saponins and their aglycones were examined for inhibitory activity on 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated 32P-incorporation into phospholipids of HeLa cells to identify new antitumor-promoter compounds.
The cephalostatins. 23. Conversion of hecogenin to a steroidal 1,6-dioxaspiro[5.5]nonane analogue for cephalostatin 11
Pettit, George R.,Moser, Bryan R.,Herald, Delbert L.,Knight, John C.,Chapuis, Jean-Charles,Zheng, Xing
, p. 1067 - 1072 (2015)
Cephalostatin 1 (1) has proved to be a remarkably potent cancer cell growth inhibitor. Since this steroidal alkaloid constituent of the marine worm Cephalodiscus gilchristi possesses a complex structure, providing preclinical supplies by total synthesis continues to be challenging. Therefore, syntheses of less complex structural modifications of this important pyrazine have also received substantial attention. Herein are summarized the synthesis of [5.5]spiroketal 5, a simplified right-side steroidal unit of 1, in seven steps from hecogenin acetate (11) with an overall yield of 4.6%. Consistent with other SAR studies, such reduction in structural complexity compared to 1 led to loss of cancer cell growth inhibitory activity against the P388 lymphocytic leukemia cell line.
SPIROSTANOL GLYCOSIDES FROM AGAVE CANTALA
Pant, G.,Sati, O. P.,Miyahara, K.,Kawasaki, T.
, p. 1491 - 1494 (1986)
Two spirostanol glycosides, cantalasaponins -2 and -4 were isolated from the methanolic extract of the rhizomes of Agave cantala and were characterized.The first glycoside was found to be lethal against Biomphalaria glabrata, tha snail vector of the disease schistosomiasis, at a concentration of 7 ppm. Key Word Index - Agave cantala; Agavaceae; saponins; spirostanol glycosides; schistosomiasis; Biomphalaria glabrata.
A TRIGLUCOSIDE OF HECOGENIN FROM FRUITS OF AGAVE CANTALA
Varshney, I. P.,Jain, D. C.,Srivastava, H. C.
, p. 239 - 240 (1982)
The fruits of Agave cantala contain a steroidal saponin which is a glycoside of hecogenin with three molecules of glucose.Its structure has been established as α-D-glucopyranosyl(1->4)α-D-glucopyranosyl(1->4)α-D-glucopyranosyl(1->3)hecogenin.Key Word Index - Agave cantala; Agavaceae; saponin; hecogenin triglucoside.
Deoxygenative Borylation of Secondary and Tertiary Alcohols
Friese, Florian W.,Studer, Armido
supporting information, p. 9561 - 9564 (2019/06/21)
Two different approaches for the deoxygenative radical borylation of secondary and tertiary alcohols are presented. These transformations either proceed through a metal-free silyl-radical-mediated pathway or utilize visible-light photoredox catalysis. Readily available xanthates or methyl oxalates are used as radical precursors. The reactions show broad substrate scope and high functional-group tolerance, and are conducted under mild and practical conditions.
Photoinduced Deoxygenative Borylations of Aliphatic Alcohols
Wu, Jingjing,B?r, Robin M.,Guo, Lin,Noble, Adam,Aggarwal, Varinder K.
, p. 18830 - 18834 (2019/11/22)
A photochemical method for converting aliphatic alcohols into boronic esters is described. Preactivation of the alcohol as a 2-iodophenyl-thionocarbonate enables a novel Barton–McCombie-type radical deoxygenation that proceeds efficiently with visible light irradiation and without the requirement for a photocatalyst, a radical initiator, or tin or silicon hydrides. The resultant alkyl radical is intercepted by bis(catecholato)diboron, furnishing boronic esters from a diverse range of structurally complex alcohols.
Synthetic pathway to 22,23-dioxocholestanic chain derivatives and their usefulness for obtaining brassinosteroid analogues
Gómez-Calvario, Víctor,Arenas-González, Ailed,Meza-Reyes, Socorro,Montiel-Smith, Sara,Vega-Báez, José Luis,Sandoval-Ramírez, Jesús,Hernández-Linares, María Guadalupe
, p. 902 - 908 (2014/02/14)
Recognizing the functionality of the pentacyclic steroidal derivative 7a as important synthon to obtain new brassinosteroid analogs, we have accomplished the derivatization of hecogenin, a sapogenin from the 25R serie containing a carbonyl group at C-12, to a 22,23-dioxocholestanic chain derivative. Starting from hecogenin acetate (5a) or hecogenin tosylate (5b), we obtained two pentacyclic derivatives (7a and 7b) which were subjected to an oxidation reaction on the double bond at C-12(23) to obtain a 22,23- dioxocholestanic chain, with the regeneration of the carbonyl group at C-12. Reduction of the carbonyl groups lead to the 20-epi-12,23-dihydroxy-22-oxo system 11a-b. The absolute configuration of compound 11a was established by X-ray diffraction analysis.
Steroidal glycosides from the bulbs of Bessera elegans and their cytotoxic activities
Matsuo, Yukiko,Akagi, Nana,Hashimoto, Chisato,Tachikawa, Fumito,Mimaki, Yoshihiro
, p. 244 - 256 (2014/01/06)
Examination of the bulbs of Bessera elegans (Liliaceae) led to isolation of nine new and five known steroidal glycosides. The structures of the nine compounds were determined based on the results of spectroscopic analysis, including two-dimensional NMR, and hydrolysis followed by chromatographic and spectroscopic analysis. The isolated compounds and derivatives were evaluated for cytotoxicity against HL-60 human promyelocytic leukemia cells, A549 human lung adenocarcinoma cells, and TIG-3 normal human diploid fibroblasts. One compound, the pseudo-furostanol glycoside, induced apoptosis in HL-60 and A549 cells in a time-dependent manner and cell-cycle arrest at the G0/G1 phase in A549 cells.
Synthesis of the antiproliferative agent hippuristanol and its analogues via Suárez cyclizations and Hg(II)-catalyzed spiroketalizations
Ravindar, Kontham,Reddy, Maddi Sridhar,Lindqvist, Lisa,Pelletier, Jerry,Deslongchamps, Pierre
experimental part, p. 1269 - 1284 (2011/04/26)
A full account of the synthesis of hippuristanol and its analogues is described. Hecogenin acetate was identified as a suitable and economical starting material for this work, and substrate-controlled stereoselection was obtained throughout the construction of the key spiroketal unit. Suárez cyclization was first used, but Hg(II)-catalyzed spiroketalization of the 3-alkyne-1,7-diol motif was finally identified as the most convenient strategy.(Figure Presented)
Efficient synthetic approach to potent antiproliferative agent hippuristanol via Hg(II)-catalyzed spiroketalization
Ravindar, Kontham,Reddy, Maddi Sridhar,Lindqvist, Lisa,Pelletier, Jerry,Deslongchamps, Pierre
supporting information; experimental part, p. 4420 - 4423 (2010/12/18)
Figure Presented. The steroidal natural product hippuristanol targets eukaryotic translation initiation factor (eIF)4A which plays a pivotal role in translation in eukaryotic cells. Now an efficient synthesis of hippuristanol from 11-ketotigogenin is reported. The synthesis features a rapid construction of a spiroketal unit via Hg(OTf)2-catalyzed oxidation/ spiroketalization of the 3-alkyn-1,7-diol motif.
