- Total synthesis of incargranine A
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Synthetic studies into the origins of the alkaloid incargranine A have resulted in the development of a four-step (longest linear sequence) total synthesis. This synthesis has been scaled-up to provide gram-scale quantities of material, which would alternatively require extraction of several metric-tons of dried-whole Chinese Trumpet-Creeper plants (Incarvillea mairei var. grandiflora).
- Brown, Patrick D.,Lawrence, Andrew L.
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supporting information
p. 1698 - 1702
(2019/02/20)
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- Total synthesis of incarvilleatone and incarviditone: Insight into their biosynthetic pathways and structure determination
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A concise biomimetic total synthesis of incarvilleatone and incarviditone is achieved in one pot via the highly stereoselective hetero-and homodimerization of (±)-rengyolone, respectively. The structure of incarviditone is revised on the basis of spectroscopic and computational evidence.
- Zhao, Kun,Cheng, Gui-Juan,Yang, Hongzhi,Shang, Hai,Zhang, Xinhao,Wu, Yun-Dong,Tang, Yefeng
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supporting information
p. 4878 - 4881
(2013/01/15)
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- Tandem sequence of phenol oxidation and intramolecular addition as a method in building heterocycles
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A tandem phenol oxidation-Michael addition furnishing oxo- and -aza-heterocycles has been developed. Dirhodium caprolactamate [Rh 2(cap)4] catalyzed oxidation by T-HYDRO of phenols with alcohols, ketones, amides, carboxylic acids, and N-Boc protected amines tethered to their 4-position afforded 4-(tert-butylperoxy)cyclohexa-2,5-dienones that undergo Bronsted acid catalyzed intramolecular Michael addition in one-pot to produce oxo- and -aza-heterocycles in moderate to good yields. The scope of the developed methodology includes dipeptides Boc-Tyr-Gly-OEt and Boc-Tyr-Phe-Me and provides a pathway for understanding the possible transformations arising from oxidative stress of tyrosine residues. A novel method of selective cleavage of O-O bond in hindered internal peroxide using TiCl4 has been discovered in efforts directed to the construction of cleroindicin F, whose synthesis was completed in 50% yield over just 3 steps from tyrosol using the developed methodology.
- Ratnikov, Maxim O.,Farkas, Linda E.,Doyle, Michael P.
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p. 10294 - 10303
(2013/01/15)
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- Enantioselective total synthesis of all of the known chiral cleroindicins (C-F): Clarification among optical rotations and assignments
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(Chemical Equation Presented) Enantioselective syntheses of all of the named chiral members of the cleroindicin family (C-F) are reported. This effort demonstrates the synthetic utility of a 2,4-dihydroxybenzaldehyde as a starting material for natural pro
- Wenderski, Todd A.,Huang, Shenlin,Pettus, Thomas R. R.
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supporting information; experimental part
p. 4104 - 4109
(2009/09/25)
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- Oxidative de-aromatization of para-alkyl phenols into para-peroxyquinols and para-quinols mediated by oxone as a source of singlet oxygen
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(Chemical Equation Presented) Easy does it: Easily handled and environmentally safe oxone generates singlet oxygen which effects the simple and selective oxidative de-aromatization of para-alkyl phenols 1 into para-peroxyquinols 2 under very mild conditions with good to excellent yields. A one-pot access to para-quinols 3 from 1 is also possible after treatment of the crude reaction mixture with sodium thiosulfate.
- Carreno, M. Carmen,Gonzalez-Lopez, Marcos,Urbano, Antonio
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p. 2737 - 2741
(2007/10/03)
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- ISOLATION OF CORNOSIDE FROM OLEA EUROPAEA AND ITS TRANSFORMATION INTO HALLERIDONE
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Olea europaea contains, besides oleuropein, demethyloleuropein, verbascoside and ligstroside, cornoside which can be easily transformed into halleridone.Key Word Index - Olea europea; Oleaceae; oleuropein; cornoside; halleridone; secoiridoid.
- Bianco, Armandodoriano,Scalzo, Roberto Lo,Scarpati, Maria Luisa
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p. 455 - 457
(2007/10/02)
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- BIOGENESIS-LIKE TRANSFORMATION OF SALIDROSIDE TO RENGYOL AND ITS RELATED CYCLOHEXYLETANOIDS OF FORSYTHIA SUSPENSA
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Photooxygenation of salidroside (8) in methanol in presence of Rose Bengal afforded cornoside (9), which, on high pressure hydrogenation with 5percent palladium on activated carbon, yielded rengyoside B (6).Reduction of 6 with sodium borohydride gave rengyoside A(5) stereoselectively.By enzymatic hydrolysis, 9, 6 and 5 furnished rengyolone (4), rengyoxide (3) and rengyol (1), respectively. Similerly, p-hydroxyphenylethanol (10), the aglycone part of salidroside (8), was oxygenated photochemically to a dienone alcohol, which cyclized spontaneously to rengyolone (4).Hallerone (17) was obtained by the photooxygenation of p-hydroxyphenylethyl acetate (10b).Thus the plausible biosynthetic routes from salidroside (8) to rengyol (1) and the related natural cyclohexylethanoids were simulated chemically.
- Endo, Katsuya,Seya, Kazuhiko,Hikino, Hiroshi
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p. 3673 - 3682
(2007/10/02)
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