- Preparation of Structurally Diverse Compounds from the Natural Product Lycorine
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The synthesis of a 52-member compound collection from the natural product lycorine is reported, highlighted by divergent cross-coupling and substitution strategies and an unusual ring rearrangement induced by reaction with aryne intermediates.
- Tasker, Sarah Z.,Cowfer, Amanda E.,Hergenrother, Paul J.
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supporting information
p. 5894 - 5898
(2018/09/25)
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- Total synthesis of (±)-Lycorine from the endo -cycloadduct of 3,5-dibromo-2-pyrone and (E)-β-borylstyrene
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A new synthetic route to (±)-lycorine, starting from the endo-cycloadduct of 3,5-dibromo-2-pyrone and (E)-β-borylstyrene, is reported. Boronate oxidation and a set of reactions including face-selective epoxidation provided the pivotal C1-OH group and C3/C3a double bond.
- Shin, Hyeong-Seob,Jung, Yong-Geun,Cho, Hyun-Kyu,Park, Yong-Gyu,Cho, Cheon-Gyu
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p. 5718 - 5720
(2015/02/19)
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- Potential intermediate, (±)-di-o-acetyl-3α-phenylselanyl-3,3a-dihydro-B-nor-6,7a- secolycorin-5-one for synthesis of the Amaryllidaceae alkaloid lycorine: Formal and total syntheses of (±)-lycorine
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Formal and total syntheses of the Amaryllidaceae alkaloid, (±)-lycorine 1, were achieved by new synthetic routes via (±)-di-o-acetyl-3α-phenylselanyl-3,3a-dihydro-B-nor-6,7a- secolycorin-5-one 32. Namely, stereoselective intramolecular Diels-Alder reaction of triene ester 5 afforded, in good yield, the cis-lactone 6, which was converted into β(stereochemical)-hydroxy-γ-lactam 23. Oxidation of silyl ether 24 with m-chloroperbenzoic acid gave only β-(tert-butyldimethylsiloxy)-α-epoxide 25, the stereostructure of which was determined by its X-ray crystallographic analysis. Payne rearrangement of compound 25 and successive acetylation furnished α(stereochemical)-acetoxy-β(stereochemical)-epoxy γ-lactam 29, which was transformed into (±)-lycorine 1 by construction of the B ring. Formal total synthesis of (±)-lycorine 1 is also described.
- Hoshino, Osamu,Ishizaki, Miyuki,Kamei, Keisuke,Taguchi, Minoru,Nagao, Takashi,Iwaoka, Kiyoshi,Sawaki, Shohei,Umezawa, Bunsuke,Iitaka, Yoichi
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p. 571 - 580
(2007/10/03)
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- A New and Stereoselective Synthetic Route to an Amaryllidaceae Alkaloid, (+/-)-Lycorine
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Formal and total syntheses of an Amaryllidaceae alkaloid, (+/-)-lycorine, were achieved by a new synthetic route via (+/-)-3-(phenylseleno)-seco-dihydro-B-norlycorin-5-one.
- Hoshino, Osamu,Ishizaki, Miyuki,Kamei, Keisuke,Taguchi, Minoru,Nagao, Takashi,et al.
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p. 1365 - 1368
(2007/10/02)
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- Phosphatidylpyrrolophenanthridine Alkaloids from Zephyranthes Flava
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Four new alkaloidal phospholipids, 2-O-glycerophosphoryllycorine, phosphatidyllycorines, phosphatidylpseudolycorines and phosphatidyllycorinium methocation, were isolated from the flowers of Zephyranthes flava.The structures of these compounds were established by comprehensive spectral analyses, chemical transformations and synthesis, where possible.The biological profile of this novel group of alkaloidal conjugates is appraised.Key Word Index - Zephyranthes flava; Amaryllidaceae; flowers; phosphatidylpyrrolophenanthridines; 2-O-glycerophosphoryllycorine, phosphatidyllycorines, phosphatidylpseudolycorines, phosphatidyllycorinium methocation; biological activity.
- Ghosal, Shibnath,Singh, Sushil K.,Unnikrishnan, Sankara G.
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p. 823 - 828
(2007/10/02)
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- Stereoselective Transformation of the Alkaloid Lycorine to O-Demethylungiminorine and Ungiminorine
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Diacetyllycorine, an Amaryllidaceae alkaloid, was transformed stereoselectively to the more heavily oxygenated congener, O-demethylungiminorine, by a route similar to that suggested for the biosynthesis of narcissidine.Similarly, acetylhippamine was converted to ungiminorine.A method of high yield conversion of lycorine to hippamine is also described. - The above transformations constitute a formal total synthesis of ungiminorine.Keywords--- Amaryllidaceae alkaloid; lycorine; hippamine; ungiminorine; O-demethylungiminorine; lycorine-chlorohydrin; permanganate oxidation; phosphoryl chloride; stereoselective hydroxylation; distorted boat conformation
- Toda, Jun,Sano, Takehiro,Tsuda, Yoshisuke,Itatani, Yoshitaka
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p. 1322 - 1332
(2007/10/02)
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- A MODIFIED TOTAL SYNTHESIS OF (+/-)-LYCORINE
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A modified total synthesis of lycorine was accomplished starting from the lactam-ester (5).Selective reduction of the lactam carbonyl of 5, followed by cyclization gave 5-oxolycorene (4).Epoxidation of 4 gave stereoselectively the α-epoxide (9).Repeated application of Sharpless method to convert epoxide into allylic alkohol and acetylation of the product gave diacetyl 5-oxolycorine (19).Lithium aluminium hydride reduction of 19 gave (+/-)-lycorine.
- Sano, T.,Kashiwaba, N.,Toda, J.,Tsuda, Y.,Irie, H.
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p. 1097 - 1100
(2007/10/02)
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