42900-89-0Relevant articles and documents
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Kraiss et al.
, p. 2359 (1973)
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Acceleration effect of an allylic hydroxy group on ring-closing enyne metathesis of terminal alkynes: Scope, application, and mechanistic insights
Imahori, Tatsushi,Ojima, Hidetomo,Yoshimura, Yuichi,Takahata, Hiroki
supporting information; experimental part, p. 10762 - 10771 (2009/12/01)
An interesting acceleration effect of an allylic hydroxy group on ring-closing enyne metathesis has been found. Ring-closing enyne metathesis of terminal alkynes possessing an allylic hydroxy group proceeded smoothly without the ethylene atmosphere generally necessary to promote the reaction. The synthesis of (+)-isofagomine with the aid of this efficient reaction has been demonstrated. Mechanistic studies of the acceleration effect were also carried out. Results of NMR studies suggested that the reaction proceeded via an "ene-then-yne" pathway. Kinetic studies indicated switching of the rate-determining step as a consequence of the presence of an allylic hydroxy group. These results suggest acceleration of the reentry step of Ru-carbene species by the allylic hydroxy group.
Syntheses and biological evaluation of vinblastine congeners.
Kuehne, Martin E,Bornmann, William G,Marko, Istvan,Qin, Yong,LeBoulluec, Karen L,Frasier, Deborah A,Xu, Feng,Mulamba, Tshilundu,Ensinger, Carol L,Borman, Linda S,Huot, Anne E,Exon, Christopher,Bizzarro, Fred T,Cheung, Julia B,Bane, Susan L
, p. 2120 - 2136 (2007/10/03)
Sixty-two congeners of vinblastine (VLB), primarily with modifications of the piperidine ring in the carbomethoxycleavamine moiety of the binary alkaloid, were synthesized and evaluated for cytotoxicity against murine L1210 leukemia and RCC-2 rat colon cancer cells, and for their ability to inhibit polymerization of microtubular protein at 10(7) M concentrations was found for L1210 inhibition by these compounds, with the most active 1000x as potent as vinblastine.