Syntheses and biological evaluation of vinblastine congeners
作者:Martin E. Kuehne、William G. Bornmann、Istvan Markó、Yong Qin、Karen L. LeBoulluec、Deborah A. Frasier、Feng Xu、Tshilundu Mulamba、Carol L. Ensinger、Linda S. Borman、Anne E. Huot、Christopher Exon、Fred T. Bizzarro、Julia B. Cheung、Susan L. Bane
DOI:10.1039/b209990j
日期:——
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 <10−6 M, and for induction of spiralization of microtubular protein, and for microtubular disassembly at 10−4 M concentrations. An ID50 range of >107 M concentrations was found for L1210 inhibition by these compounds, with the most active 1000× as potent as vinblastine.
Microbial Baeyer-Villiger Oxidation of Bicyclo[4.3.0]ketones by Two Recombinant E. coli Strains. A Novel Access to Indole Alkaloids
作者:Marko D. Mihovilovic、Bernhard Müller、Margaret M. Kayser、Peter Stanetty
DOI:10.1055/s-2002-25340
日期:——
Recombinant Escherichia coli overexpressing Pseudomonas sp. NCIMB 9872 cyclopentanone monooxygenase (CPMO; E.C. 1.14,13.16) and Acinetobacter sp. NCIMB 9871 cyclohexanonemonooxygenase (CHMO; E.C. 1.14.13.22) have been utilized in whole-cell biotransformations of prochiral bicyclo[4.3.0]ketones. The lactones produced in a biocatalytic Baeyer-Villigeroxidation represent key intermediates for the synthesis
Formation of lactones via a radical ring closure mechanism
作者:Athelstan L. J. Beckwith、Paul E. Pigou
DOI:10.1039/c39860000085
日期:——
Suitable alkenoyloxymethyl iodides or selenides are converted into lactones upon treatment with tributyl-stannane or -germane; the reaction involves highly regioselective and stereoselective ringclosure of alkenoyloxymethyl radicals (1).