- A revision of the positive sign of the optical rotation and its maximum value of α-eudesmol
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The ether extract of the liverwort Porella perrottetiana afforded (-)- α-eudesmol, which showed an opposite sign of the optical rotation to that found in higher plants. Present work on the absolute configuration and an optical purity of (-)-α-eudesmol strongly suggested that the positive values (e.g. + 28.5°) described in many previous papers should be revised. Since the absolute configuration of (-)-α-eudesmol was identical to that of (+)- β-eudesmol found in the higher plants, it was apparent that the expression of the positive sign might be revised to (-)-α-eudesmol. The optical purity, reconfirmation of the absolute configuration and synthesis of (-)-α-eudesmol will be discussed.
- Toyota, Masao,Yonehara, Yumiko,Horibe, Isao,Minagawa, Kazuyuki,Asakawa, Yoshinori
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- TERPENOIDS FROM PLANTS OF THE FAMILY CUPRESSACEAE. SESQUITERPENE ALCOHOLS FROM THE NEEDLES OF Microbiota decussata
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The sesquiterpene alcohols 5S,8S-germacra-1E,6E-dien-5-ol, (+)-α-bisabolol, hedycaryol, and β-eudesmol and also the previously undescribed alcohols thujopsan-2α-ol (I) and microbiotol.Microbiotol is a tricyclic tertiary alcohol with the empirical formula C15H26O, mp 112-113 deg C, containing in its molecule four tertiary methyl groups and cyclopropane ring.
- Raldugin, V. A.,Storozhenko, V. G.,Rezvukhin, A. I.,Pentegova, V. A.,Gorovoi, P. G.,Baranov, V. I.
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- Stereoselective total synthesis of (-)-α-eudesmol, a P/Q-type calcium channel blocker
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Practical and stereoselective total synthesis of (-)-αeudesmol 1, a P/Q-type calcium channel blocker, has been achieved with the key step being a cyclopropane ring opening accompanying introduction of a hydroxyl group. (+)-Carissone is used as a key intermediate.
- Aoyama,Araki,Konoike
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- Unified Approach to ent -Eudesmane-Type Terpenoid Synthesis: Total Synthesis of Sinupol and Eutyscoparin A
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ent-Eudesmane-type terpenoids constitute a large class of natural products derived from plants, animals, and bacteria. We describe a synthetic approach to two ent-eudesmane-type terpenoids, sinupol and eutyscoparin A, that relies on a key π-facial-and endo/exoselective intramolecular Diels Alder reaction to set the C-5 C-10 stereotriads. Further key transformations of trans-fused decalin include conversion to methyl ketone via a versatile thioester intermediate and appropriate functionalization toward target compounds.
- Ota, Koichiro,Kamaike, Kazuo,Miyaoka, Hiroaki
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p. 689 - 696
(2021/10/29)
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- Short and efficient hemisynthesis of α-eudesmol and cryptomeridiol
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The aerial part of Dittrichia viscosa yielded two sesquiterpenes, isocostic acid (1) and ilicic acid (2), on multigram scale. These acids are appropriate starting materials for short and facile syntheses of α-eudesmol (5) and cryptomeridiol (6), natural products featuring anti-Alzheimer and anti-spasmodic properties. Compounds 5 and 6 were obtained in three steps in overall yields of 70% and 52%, respectively.
- Tebbaa, Mohamed,El Hakmaoui, Ahmed,Benharref, Ahmed,Akssira, Mohamed
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p. 3769 - 3771
(2011/08/06)
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- Ilicic Acid as a Natural Quiron for the Efficient Preparation of Bioactive α- and β-Eudesmol
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An efficient procedure for the isolation of the sesquiterpene ilicic acid (3) on a multigram scale of extracts obtained from aerial parts of Inula viscosa (Asteraceae) was developed. Acid 3 is an appropriate starting material for short, enantio-specific s
- Barrero, Alejandro F.,Herrador, M. Mar,Arteaga, Pilar,Catalan, Julieta V.
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experimental part
p. 3589 - 3594
(2009/12/01)
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- An efficient synthetic strategy for introduction of C3-C4 double bond into eudesmane skeleton: First total synthesis of (+)-chrysanthemol
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The first enantioselective synthesis of (+)-chrysanthemol 1 was carried out starting from (+)-dihydrocarvone in ten steps. In our studies, a facile synthetic strategy has been developed for introduction of C3-C4 double bond into a eudesmane skeleton.
- Chen, Yonggang,Zhou, Gang,Xiong, Zhaoming,Liu, Lijun,Li, Yulin
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p. 261 - 264
(2007/10/03)
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- Total synthesis of neohedycaryol. Its possible role in the biosynthesis of eudesmane sesquiterpenes
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The total synthesis of neohedycaryol (4), the C(9)-C(10) double bond regioisomer of the germacrane sesquiterpene hedycaryol, was accomplished in 10 steps from the known dione 6. A Marshall fragmentation of the intermediate mesylate 14 was used to prepare the trans,trans-cyclodeca-1,6-diene ring present in neohedycaryol. During the synthesis of 14, a pronounced example of through-bond interactions (TBI) was observed. The preferred elongated chair conformation of neohedycaryol was demonstrated spectroscopically and by chemical conversion into α-, β-, and γ-eudesmol. These findings indicate that the occurrence of neohedycaryol as a precursor in the biosynthesis of epi-eudesmanes as proposed in the literature is unlikely. The preference of neohedycaryol for the elongated chair conformation further shows that the compound occupies the meso form. This implies that neohedycaryol may act as a precursor in the biosynthesis of both ent- and usual eudesmanes.
- Minnaard, Adriaan J.,Stork, Gerrit A.,Wijnberg, Joannes B.P.A.,De Groot, Aede
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p. 2344 - 2349
(2007/10/03)
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- First total synthesis of (+)-chrysanthemol
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The first total synthesis of (+)-chrysanthemol (1) has been described starting from (+)-dihydrocarvone (4). The features of our synthesis are the high yield introduction of C3-C4 double bond into eudesmane skeleton and rearrangement of epoxide to allylic alcohol promoted by BF3?OEt2-Bu4NI reagent. In our synthesis, (+)-α-eudesmol (5) has been used as a key intermediate.
- Chen, Yonggang,Xiong, Zhaoming,Zhou, Gang,Yang, Jiong,Li, Yulin
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p. 1289 - 1290
(2007/10/03)
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- Biotransformation of (+/-)-4,8-dimethylcyclodeca-3(E),7(E)-dien-1β-ol and (+)-Hedycaryol by Cichorium intybus
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The biotransformation of the synthetic (E,E)-1,5-cyclodecadienol 5 and (+)-hedycaryol (11) by a root suspension of fresh chicory has been investigated.Incubation of 5 with a root suspension gave a 2:1 mixture of epimeric eudesmanediols 7a and 7b whereas 11 was selectively converted into cryptomeridiol (12).An explanation for the obtained results is proposed.
- Piet, Dennis P.,Minnaard, Adriaan J.,Heyden, Karel A. van der,Franssen, Maurice C. R.,Wijnberg, Joannes B. P. A.,Groot, Aede de
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p. 243 - 254
(2007/10/02)
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