- Synthesis of a new class of bisheterocycles via the Heck reaction of eudesmane type methylene lactones with 8-bromoxanthines
-
The eudesmane-type methylene lactones (isoalantolactone, alantolactone, 4,15-epoxyisoalantolactone, 2′,2′-dichloro-4H-spiro[cyclopropane-1′,4-eudesma-11(13)-en-8β,12-olide], and alantolactone) react with 8-bromoxanthines (8-bromocaffeine, 8-bromotheobromine, 8-bromo-3-butyltheobromine, 8-bromotheophylline, 8-bromo-9-butyltheophylline) under Heck reaction conditions to produce the target (E)-13-(2,6-dioxo-2,3-dihydro-1H-purin-8-yl)eudesma-4(15),11(13)-dien-8β,12-olides and the subsequent endocyclic isomers - 11-(2,6-dioxo-2,3-dihydro-1H-purin-8-yl)-13-normethyleudecma-4(15)-7(11)-dien-8α,12-olides. It was revealed that the yield and product ratio depends on the reaction conditions and the structure of methylene lactone. The effectiveness of Pd(OAc)2–caffeine catalytic system has been demonstrated in this reaction. The electric eel acetylcholinesterase inhibitory activity of the eudecmanolide-xanthine hybrids was evaluated. Among the new type bisheterocycles compound 27 with butyl and 2-oxodecahydronaphtho[2,3-b]furan-3(2H)-ylidene)methyl substituents at C-7 and C-8 of the xanthine core showed moderate activity with IC50 value of 40?μM.
- Patrushev, Sergey S.,Rybalova, Tatyana V.,Ivanov, Igor D.,Vavilin, Valentin A.,Shults, Elvira E.
-
p. 2717 - 2726
(2017/04/14)
-
- A general, concise, 'collective' approach to eudesmanolide sesquiterpenoids: Total synthesis of bioactive atractylenolides I-IV and related natural products
-
Total synthesis of seven bioactive atractylenolide-type eudesmanolides from Hagemann's ester, following, a short, scalable, adaptable, and diversity oriented protocol, has been accomplished. This effort opens a gateway to access through synthesis an exceptionally potent and promising group of natural products and their congeners of contemporary interest.
- Ramesh, Subburethinam,Mehta, Goverdhan
-
p. 5545 - 5548
(2015/09/21)
-
- Synthetic transformations of methylenelactones of eudesmanic type. Behavior of isoalantolactone under the conitions of heck reaction
-
By Heck reaction of isoalantolactone with aryl bromides or aryl iodides (3aR,4aS, 8aR,9aR,E)-3-arylmethylidene-8a-methyl-5- methylidenedecahydronaphtho[2,3-b]furan-2(3H)-ones and (4aS,8aR,9aS)-3- arylmethyl-8a-methyl-5-methylidene-4a,5,6,7,8,8a,9,9a-octahydronaphtho[2,3-b] furan-2(4H)-ones, products of the double bond shift, were synthesized. The yields of the arylation products depend on the nature of the catalytic system and on the structure of the aryl halide. The structures of (3aR,4aS,8aR,9aR,E)- 3-(3,4-dimethoxybenzylidene)-8amethyl-5-methylidenedecahydronaphtho[2,3-b] furan-2(3H)-one and (4aS,8aR,9aS)-3-(2-methylsulfanylbenzyl)-8amethyl-5- methylidene-4a,5,6,7,8,8a,9,9a-octahydronaphtho[2,3-b]furan-2(4H)-one were proved by XRD analysis. Pleiades Publishing, Ltd., 2010.
- Belovodskii,Shults,Shakirov,Bagryanskaya,Gatilov,Tolstikov
-
experimental part
p. 1719 - 1734
(2011/03/18)
-
- Dimerization of butenolide structures. A biomimetic approach to the dimeric sesquiterpene lactones (±)-biatractylolide and (±)- biepiasterolide
-
The biomimetic synthesis of the bisesquiterpene lactones (±)-biatractylolide 1 and (±)-biepiasterolide 2 via dimerization of the captodative stabilized radical 8 is reported. Atractylon 7 has also been shown to be a possible intermediate during the biosynthesis of biatractylolide 1, biepiasterolide 2, atractylolide 3, and hydroxyatractylolide 4.
- Bagal, Sharanjeet K.,Adlington, Robert M.,Baldwin, Jack E.,Marquez, Rodolfo
-
p. 9100 - 9108
(2007/10/03)
-
- Biomimetic synthesis of biatractylolide and biepiasterolide
-
(Matrix presented) The biomimetic synthesis of the bisesquiterpenoids biatractylolide 1 and biepiasterolide 2 is reported.
- Bagal, Sharanjeet K.,Adlington, Robert M.,Baldwin, Jack E.,Marquez, Rodolfo,Cowley, Andrew
-
p. 3049 - 3052
(2007/10/03)
-
- Isolation and Structural Elucidation of Four Sesquiterpenes from Chloranthus japonicus (Chloranthaceae)
-
The four sesquiterpenes shizukanolide (1), dehydro-shizukanolide (2), glechomanolid (3) and isofuranodiene (4) were isolated from Chloranthus japonicus Seib. (Hitori-shizuka in Japanese, Chloranthaceae).Their absolute structures have been established on the basis of their phisycal and chemical properties.Dehydro-shizukanolide showed moderate antifungal activity.
- Kawabata, Jun,Tahara, Satoshi,Mizutani, Junya
-
p. 1447 - 1454
(2007/10/02)
-
- An Annelation Approach to the Synthesis of Eudesmane and Elemane Sesquiterpene Lactones. Total Synthesis of dl-Dihydrocallitrisin, dl-7,8-Epialantolactone, dl-7,8-Epiisoalantolactone, and dl-Atractylon
-
An annelation approach to the synthesis of eudesmane sesquiterpenes is described.The 1,6-annelation reagent α-carbomethoxy-β-methyl-γ-methylidene-Δα,β-butenolide (1) is used to construct the linear tricyclic lactone 2,5,6,7,8,8a,9,9aβ-octahydro-8aβ-methyl-2-oxonaphthofuran-3-carboxylic acid methyl ester (2).The conversion of 2 to dl-dihydrocallitrisin (3), dl-7,8-epialantolactone (4), dl-7,8-epiisoalantolactone (5), and dl-atractylon (6) is detailed.Studies directed toward synthesis of the elemane sesquiterpene lactones vernomenin and vernolepin also are presented.
- Schultz, Arthur G.,Godfrey, Jollie D.
-
p. 2414 - 2428
(2007/10/02)
-
