158982-11-7Relevant academic research and scientific papers
The scope and mechanism of phosphonium-mediated SNAr reactions in heterocyclic amides and ureas
Wan, Zhao-Kui,Wacharasindhu, Sumrit,Levins, Christopher G.,Lin, Melissa,Tabei, Keiko,Mansour, Tarek S.
, p. 10194 - 10210 (2008/04/12)
(Chemical Equation Presented) An efficient "one-step" synthesis of cyclic amidines and guanidines has been developed. Treatment of cyclic amides and ureas with benzotriazol-l-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP), base, and nitrogen nucleophiles leads to the formation of the corresponding cyclic amidines and guanidines, typically in good to excellent yields. This method has also been used to prepare heteroaryl ethers and thioethers using phenol and thiophenol nucleophiles. Time course NMR and HPLC-MS studies have facilitated explicit characterization of the proposed intermediates (the phosphonium salt and HOBt adduct); the data reveal a stepwise reaction pathway.
An efficient direct amination of cyclic amides and cyclic ureas
Wan, Zhao-Kui,Wacharasindhu, Sumrit,Binnun, Eva,Mansour, Tarek
, p. 2425 - 2428 (2007/10/03)
An efficient one-step amination of cyclic amides and ureas has been developed. Treatment of cyclic amides and cyclic ureas with BOP in the presence of DBU in various solvents led to the formation of cyclic amidines and cyclic guanidines in good to excellent yields. Concise syntheses of biologically intriguing kinetin and potent kinase inhibitor olomoucin were thus achieved in just one and two steps, respectively.
Cytokinin-derived cyclin-dependent kinase inhibitors: Synthesis and cdc2 inhibitory activity of olomoucine and related compounds
Havlí?ek, Libor,Hanu?, Jan,Vesely, Jaroslav,Leclerc, Sophie,Meijer, Laurent,Shaw, Gordon,Strnad, Miroslav
, p. 408 - 412 (2007/10/03)
Cyclin-dependent kinases (cdk) have recently raised considerable interest in view of their essential role in the regulation of the cell division cycle. The structure-activity relationships of edk inhibition showed that the 1, 3, and 7 positions of the purine ring must remain free, probably for a direct interaction, in which it behaves as a hydrogen bond acceptor. Olomoucine (6-(benzylamino)-2-[(2-hydroxyethyl)amino]-9-methylpurine, OC), roscovitine (6-(benzylamino)2(R)-[[1-(hydroxymethyl)propyl]amino]-9- isopropylpurine), and other N6,2,9-trisubstituted adenines were found to exert a strong inhibitory effect on the p34(cdc2)/cyclin B kinase. Removal or change of the side chain at position 2 or the hydrophobic group at position 9 dramatically decreased the inhibitory activity of olomoucine or roscovitine. Inhibition of cdk with OC and related compounds clearly arrests cell proliferation of many tumor cell lines at G1/S and G2/M transitions and also triggers apoptosis in the target tumor cells in vitro and in vivo. Thus, from a pharmacological point of view, OC may represent a model compound for a new class of antimitotic and antitumor drugs.
