3186-86-5Relevant articles and documents
Synthesis and in vitro antitumor activities of lupeol dicarboxylic acid monoester derivatives
Li, Weijie,Hao, Jing,Xiao, Yeyu
, p. 1447 - 1453 (2013)
Ten lupeol dicarboxylic acid monoester derivatives as new potent antitumor agents were synthesized and evaluated for in vitro antitumor activities against A549, LAC, HepG2 and HeLa cell lines. Among them, compounds 1-5 showed excellent antitumor activities against all tested tumor cell lines and compounds 6-10 exhibited high activities against A549, HepG2 and HeLa cells, exceeded lupeol, lupanol and doxorubicin. Compound 2 displayed the highest potent antitumor activities with IC50 values of 5.78 μM against A549 cell, 2.38 μM against LAC cell, 6.14 μM against HepG2 cell and 0.00842 μM against HeLa cell.
Preparation and molecular rearrangement of 2α, 3α-epoxy lupan-1-one catalysed by boron trifluoride and by ultraviolet irradiation+
Bose,Chanda
, p. 510 - 514 (2007/10/03)
Using lupeol 7 as lead compound 2α, 3α-epoxy lupan-1-one 11 has been synthesised by a sequence of reactions. Boron trifluoride catalysed molecular rearrangement of 11 in benzene yields 2-formyl-A-nor-lupan-1-one 15 (enolized). Same rearrangement is also achieved in dioxane under photolytic condition.
Studies on reactions of 2-bromo-3-ketotriterpenoids: Part III - Reduction of 2α-bromo and 2,2-dibromo derivatives of lupanone and methyl dihydrobetulonate with lithium aluminium hydride and sodium borohydride
Pradhan, B P,Ghosh, Pranab
, p. 1178 - 1180 (2007/10/02)
Reduction of methyl 2α-bromodihydrobetulonate/2α-bromolupanone (1/2) and methyl 2,2-dibromodihydrobetulonate/2,2-dibromolupanone (1a/2a) with LAH at room temperature results in the formation of methyl 2α-bromo-3β-hydroxydihydrobetulonate/2α-bromo-3β-hydroxylupane (3/4), methyl dihydrobetulinate/lupanol (3b,4b) and methyl 2α-bromo dihydrobetulonate/2α-bromolupanone (1/2), methyl dihydrobetulinate/lupanol (3b/4b), lupan-2β-3β-diol (5)(from 2a) respectively, while the reduction of 1/2 and 1a/2a with NaBH4 affords 3/4, 3b/4b and methyl dihydrobetulonate/lupanone (1b/2b), 3b/4b respectively.
The synthesis of nor- and bisnorlupanes
Wahhab, Amal,Ottosen, Margaret,Bachelor, Frank W.
, p. 570 - 577 (2007/10/02)
In course of our studies on geochemical biomarkers we required a series of lupane standards.We report here an efficient synthesis of lupane (1) in three steps from betulin (3) in an overall yield of 47.2 percent. 17β(H)-28-Norlupane (2) was obtained in 90
Reduction of Steroid and Triterpenoid α,β-Unsaturated Ketones with Lithium/Ethylenediamine
Pradhan, Bhim Prasad,Chakraborty, Satyajit
, p. 263 - 265 (2007/10/02)
Reduction of less sterically hindered ketone, glochidone (1) with lithium/ethylenediamine (Li/EDA) leads to the reduction of the double bond followed by that of the carbonyl group to afford thermodynamically stable alcohol, lupanol (1b).The sterically hindered α,β-unsaturated ketones such as 11-keto-triterpenoids also furnish saturated alcohols but in small proportions; the other compounds formed are obtained with reduction of the carbonyl group accompanied by dehydration or even deoxygenation.
FUNCTIONALISATION OF UNACTIVATED METHYL GROUPS THROUGH CYCLOPALLADATION REACTIONS
Baldwin, Jack E.,Jones, Richard H.,Najera, Carmen,Yus, Miguel
, p. 699 - 712 (2007/10/02)
The transformation of the organopalladium compound (3) into the corresponding deuteriated, chlorinated, or oxidized derivatives (7), (8), or (9), (11), and (12) respectively, is described.The palladation of compound (9) takes place regioselectively leadin
Lithium-Ethylenediamine as a Reducing Agent
Pradhan, Bhim Prasad,Chakrabarti, Dilip Kumar,Chakraborty, Satyajit
, p. 1115 - 1116 (2007/10/02)
In a series of triterpenoids, ketones have been converted into sterically more stable secondary alcohols, aldehydes to primary alcohols, hindered esters to acids and isopropenyl groups to isopropyl groups on reduction with lithium in ethylenediamine in high yields.
METABOLITES OF BIRD'S NEST FUNGI-19 NEW TRITERPENOID CARBOXYLIC ACIDS FROM CYATHUS STRIATUS AND CYATHUS PYGMAEUS
Ayer, William A.,Flanagan, Richard J.,Reffstrup, Torsten
, p. 2069 - 2082 (2007/10/02)
The bird's nest fungus Cyathus Striatus Willd. ex.Pers. yielded the known triterpenes glochidone (1), glochidonol (2), glochidiol (3) and glochidiol diacetate (4) as well as four new triterpenoic acids, cyathic acid (5), striatic acid (6), cyathadonic acid (7) and epistriatic acid (8).Another species, Cyathus pygmaeus Lloyd, contained cyathic acid (5) and an additional new compound, pygmaeic acid (9).The structural assignments are based on spectroscopic data and chemical correlations.
Structures of Four New Oxygenated Lupanes from Pleurostylia opposita (Celastraceae)
Dantanarayana, Anura P.,Kumar, N. Savitri,Sultanbawa, M. Uvais S.,Balasubramaniam, Sinnathamby
, p. 2717 - 2723 (2007/10/02)
Four new oxygenated lupanes isolated from the steam bark of Pleurostylia opposita (Wall) Alston (Celastraceae) have been shown to be lupa-5,20(29)-dien-3-one (2), 6β,20-dihydroxylupan-3-one (5), 3β,6β-dihydroxylup-20(29)-ene (6), and 6β,28-dihydroxylup-20(29)-en-3-one (8).The structures of these compounds were established on the basis of spectroscopic (1H n.m.r. and mass spectra) and chemical evidence.Deshielding of three methyl signals in the 1H n.m.r. spectra of 6β-hydroxylupane derivatives has been attributed to 1,3-diaxial interaction between the relevant methyl group and the 6β-hydroxy-group.
