88979-97-9Relevant academic research and scientific papers
Concise and efficient total syntheses of (±)-sarcophytols A and B, two antitumor cembrane diterpenoids, by an intramolecular Mcmurry olefination strategy
Li, Wei-Dong Z.,Li, Ying,Li, Yulin
, p. 965 - 968 (2007/10/03)
Efficient total syntheses of (±)-sarcophytol A and B, two antitumor cembrane diterpenoids isolated from marine soft corals, were presented by a low-valent titanium-mediated intramolecular McMurry olefination strategy starting from trans, trans-farnesol.
A ketal Claisen rearrangement for α-ketol isoprene unit elongation: application to a practical synthesis of sarcophytol A intermediate
Takayanagi, Hisao,Sugiyama, Shigeo,Morinaka, Yasuhiro
, p. 751 - 756 (2007/10/02)
A new ketal Claisen rearrangement using the ketal 10 for the isoprene unit elongation which affords terminal α-ketol terpenoid is presented.Its efficiency is demonstrated by successful transformation of the product of this reaction, the α-ketol 20, into 2, the acyclic precursor of sarcophytol A total synthesis, by two alternative routes via the β,γ-unsaturated aldehyde 24 and the allylic alcohol 28.
Total Synthesis of Sarcophytol A, an Anticarcinogenic Marine Cembranoid
Takayanagi, Hisao,Kitano, Yosunori,Morinaka Yasuhiro
, p. 2700 - 2706 (2007/10/02)
A highly stereo- and enantioselective total synthesis of sarcophytol A (1), a marine cembranoid promising as a cancer chemopreventive agent, is described.The nitrile 10 obtained Z-selectively (Z:E = >35:1) by the Horner-Emmons reaction of (E,E)-farnesal (5) with the phosphononitrile 9 in 91percent yield was converted to the conjugated 2(Z),4(E)-dienal 3 in which the terminal (E)-methyl group was functionalized.Intramolecular alkylation of the cyanohydrin TMS ether of 3 provided the macrocyclic ketone 2 in 79percent of overall yield from 3 without isolation of the cyclic cyanohydrin 20 as well as its TMS ether 19.Reduction of 2 with several chiral LiAlH4 reagents afforded 1 highly enantioselectively (87-93percent ee) in 78-97percent yield from which enantiomerically pure 1 (>99percent ee) was readily obtained upon a single recrystallization.
Total Syntheses of Both Enantiomers of Sarcophytols A and T Based on Stereospecific Wittig Rearrangement
Kodama, Mitsuaki,Yoshio, Suzuyo,Yamaguchi, Shinji,Fukuyama, Yoshiyasu,Takayanagi, Hisao,et al.
, p. 8453 - 8456 (2007/10/02)
Both enantiomers of sarcophytols A (1) and T (2), cembranolide diterpenes isolated from a soft coral, were syntesized from a common chiral intermediate, obtained by baker's yeast reduction, using a stereospecific Wittig rearrangement as the key step.
Stereo- and enantioselective total synthesis of sarcophytol-A
Takayanagi, Hisao,Kitano, Yasunori,Morinaka, Yasuhiro
, p. 3317 - 3320 (2007/10/02)
The first total synthesis of sarcophytol-A, a biologically important marine cembranoid, was achieved in a highly stereo- and enantioselective manner.
Stereochemical Course of the Transannular Cyclization, in Chloroform, of Epoxycembranoids Derived from the Geometrical Isomers of (14S)-14-Hydroxy-1,3,7,11-cembratetraenes
Kobayashi, Masaru,Nakano, Emiko
, p. 1947 - 1951 (2007/10/02)
A new cembranoid sarcophytol T (5a) was isolated from the soft coral Sarcophyton glaucum, and the structure was shown to be (14S)-14-hydroxy-1(E),3(Z),7(E)-cembratetraene, a geometrical isomer of the potent antitumor promoter sarcophytol A (1).Compound 5a and its geometrical isomers, sarcophytol N (6, 1Z,3Z) and sarcophytol F (7, 1E,3E), were found to be converted by autoxidation to bicyclotetradecene derivatives when kept in CHCl3 solution at room temperature, in the same way as 1 (1Z,3E).The stereochemistry of each product (4 from 1 and 5a, 12 from 6, and 16 from 7) was derived by NOE analyses and by conversion of 12 and 16 to the enantiomeric ketones 17 and 18, respectively. 4-Hydroxy-1,14-epoxy-2-ene derivatives were shown to be the immediate precursors in the transannular cyclization, while cembrene C (23), the parent hydrocarbon of 1, also reacted in CHCl3, giving the bicyclic derivatives 25.
Studies of Australian Soft Corals. XXXIII. New Cembranoid Diterpenes from a Lobophytum Species
Bowden, Bruce F.,Coll, John C.,Tapiolas, Dianne M.
, p. 2289 - 2296 (2007/10/02)
The isolation of two new cembranoid diterpenes, (14S,1E,3E,7E)-14-acetoxy-11,12-epoxycembra-1,3,7-triene and the corresponding 14-alcohol, is reported from the soft coral Lobophytum sp.A minor component in the extract (3S,4S,11S,12S,1E,7E)-3,4:11,12-bisepoxycembra-1,7-diene was identified but may be artefactual as it is the sole product of the aerial oxidation of the major metabolite (11S,12S,1E,3E,7E)-11,12-epoxycembra-1,3,7-triene.Further examples of stereospecific epoxidations are reported.
