193071-75-9Relevant academic research and scientific papers
Epothilones C, E and F
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Page 8, (2008/06/13)
Epothilone derivatives are obtained by: (1) cultivation of Sorangium cellulosum DSM 6773 in the presence of an absorption resin; (2) separation of the resin and culture followed by washing with aqueous methanol; (3) eluting the washed resin with methanol and reducing the extract; (4) partitioning the extract between methanol and hexane; (5) reducing the methanolic phase and fractionating it on a Sephadex column, and (6) isolation of the epothilones by chromatography using a methanol/water mixture. Epothilone A is followed by epothilone B, and two further fractions.
Total synthesis of epothilone A through stereospecific epoxidation of the p-methoxybenzyl ether of epothilone C
Liu, Zhi-Yu,Chen, Ze-G,Yu, Cheng-Zhi,Wang, Rui-Fang,Zhang, Ru-Zhou,Huang, Chu-Sheng,Yan, Zheng,Cao, De-Rong,Sun, Jian-Bo,Li, Gang
, p. 3747 - 3756 (2007/10/03)
The total synthesis of epothilone A is described by the coupling four segments 4 - 7a. Three of the segments, 4, 5 and 7a, have only one chiral center; all other chiral centers were introduced by simple asymmetric catalytic reactions. The key steps are the ring opening of epoxide 5 with acetylide 8 for the construction of the C12-C13 cis double bond and a practical hydrolytic kinetic resolution (HKR) developed by Jacobsen group for the introduction the chiral center at C3. Especially, the stereospecific epoxidation of 3-O-PMB epothilone C 3b through long-range effect of 3-O-PMB protecting group gave high yields of the C12 - C13 α-epoxide for the synthesis of target molecule.
Epothilone derivatives, their preparation and utilization
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Page 15-16, (2008/06/13)
Epothilone derivatives of formula (I)-(III) are new. R = H or 1-4C alkyl; Y Z = H, halo, pseudohalogen, OH, 1-6C acyloxy, 1-6C alkoxy or benzoyloxy; or Y+Z = bond or O; (a) R' = Q; A = H; B = OR1; and R" = R2; or R"+B = C(O)O, C(S)O, S(O)O, Si(R")2O or C(
Synthesis and biological activity of novel epothilone aziridines.
Regueiro-Ren,Borzilleri,Zheng,Kim,Johnson,Fairchild,Lee,Long,Vite
, p. 2693 - 2696 (2007/10/03)
[reaction: see text]. A series of 12alpha,13alpha-aziridinyl epothilone derivatives were synthesized in an efficient manner from epothilone A. The final semisynthetic route involves a formal double-inversion of stereochemistry at both the C12 and C13 posi
The olefin metathesis approach to epothilone A and its analogues
Nicolaou,He,Vourloumis,Vallberg,Roschangar,Sarabia,Ninkovic,Yang,Trujillo
, p. 7960 - 7973 (2007/10/03)
The olefin metathesis approach to epothilone A (1) and several analogues (39-41, 42-44, 51-57, 58-60, 64-65, and 67-69) is described. Key building blocks 6-8 were constructed in optically active form and were coupled and elaborated to olefin metathesis pr
Total Synthesis of Epothilones A and B
Dongfang, Meng,Bertinato, Peter,Balog, Aaron,Su, Dai-Shi,Kamenecka, Ted,et al.
, p. 10073 - 10092 (2007/10/03)
Convergent, stereocontrolled total syntheses of the microtubule-stabilizing macrolides epothilones A (2) and B (3) have been achieved. Four distinct ring-forming strategies were pursued (see Scheme 1). Of these four, three were reduced to practice. In one approach, the action of a base on a substance possessing an acetate ester and a nonenolazable aldehyde brought about a remarkably effective macroaldolization see (89 -> 90 + 91; 99 -> 100 + 101), simultaneously creating the C2-C3 bond and the hydroxyl-bearing stereocenter at C-3. Alternatively, the 16-membered macrolide of the epothilones could be fashioned through a C12-C13 ring-closing olefin metathesis (e.g. see 111 -> 90 + 117; 122 -> 105 + 123) and through macrolactonization of the appropriate hydroxy acid (e.g. see 88 -> 93). The application of a stereospecific B-alkyl Suzuki coupling strategy permitted the establishment of a cis-C12-C13 olefin, thus setting the stage for an eventual site- and diastereoselective epoxidation reaction (see 96 -> 2; 106 -> 3). The development of a novel cyclopropane solvolysis strategy for incorporating the geminal methyl groups of the epothilones (see 39 -> 40 -> 41), and the use of Lewis acid catalyzed diene-aldehyde cyclocondensation (LACDAC) (see 35 + 36 -> 37) and asymmetric allylation (see 10 -> 76) methodology are also noteworthy.
Total synthesis of epothilone A: The olefin metathesis approach
Yang,He,Vourloumis,Vallberg,Nicolau
, p. 166 - 168 (2007/10/03)
A flexible alterative route to the total synthesis of the antitumor agent epothilone A has been achieved by a highly convergent strategy involving olefin metathesis as a key step. The strategy may allow the chemical synthesis of a library of designed epothilones for biological screening.
Totalsynthese von (-)-Epothilon A
Balog, Aaron,Meng, Dongfang,Kamenecka, Ted,Bertinato, Peter,Su, Dai-Shi,et al.
, p. 2976 - 2978 (2007/10/03)
Keywords: Cyclisierungen; Epothilone; C-C-Kupplungen; Naturstoffe; Synthesemethoden
