171564-64-0Relevant academic research and scientific papers
Total synthesis of (-)-balanol
Miyabe, Hideto,Torieda, Mayumi,Inoue, Kyoko,Tajiri, Kazumi,Kiguchi, Toshiko,Naito, Takeaki
, p. 4397 - 4407 (2007/10/03)
The efficient total synthesis of (-)-balanol, a potent inhibitor of the protein kinase C, is described (-)-Balanol consists of a chiral hexahydroazepine-containing fragment and a benzophenone fragment, both of which were prepared via novel synthetic routes. The hxahydroazepine fragment was prepared in racemic form through either Bu3SnH- or SmI2-promoted radical cyclization of oxime ethers 2ab intramolecularly connected with the formyl group. SmI2-promoted radical cyclization of 2b was found to be particularly successful in the selective synthesis of the seven-membered trans-amino alcohol 8b. Preparation of the enantiomerically pure hexahydroazepine-containing fragment was achieved through the enantioselective enzymatic acetylation of racemic alcohol 9, employing the immobilized lipase from Pseudomonas sp. The benzophenone fragment was prepared in short steps through a biomimetic oxidative anthraquinone ring cleavage starting from commercially available natural chrysophanic acid 15c. This reaction proceeded via [4 + 2]-cycloaddition of single of oxygen to anthracene derivative 17c, followed by Baeyer-Villiger-type rearrangement of the resulting hydroperoxide to afford the benzophenone derivatives 22 and 23.
Total synthesis of (-)-balanol
Miyabe, Hideto,Torieda, Mayumi,Kiguchi, Toshiko,Naito, Takeaki
, p. 580 - 582 (2007/10/03)
The total synthesis of (-)-balanol, a potent protein kinase C inhibitor, is described. The synthesis includes a radical cyclization approach to the hexahydroazepine-containing fragment and a biomimetic route to the benzophenone fragment.
Total Synthesis of Balanol and Designed Analogues
Nicolaou, K. C.,Koide, Kazunori,Bunnage, Mark E.
, p. 454 - 466 (2007/10/03)
The total synthesis of balanol, a potent protein kinase C inhibitor isolated from the fungus Verticillium balanoides, is described.The hexahydroazepine fragment was prepared from D-serine through a sequence of reactions including the diastereoselective allylboration of a derived amino aldehyde and a base-induced 7-exo-tet ring closure as key steps.The benzophenone fragment was secured through the initial coupling of the two functionalised aromatic components through an ester linkage, followed by intramolecular nucleophilic attack of an aryl lithium derivative to form the desired ketone bridge.After coupling of the two balanol domains, the adoption of benzyl-derived protecting groups for the latent functionalities then allowed the liberation of balanol in a single step by catalytic hydrogenolysis.Finally, the newly developed synthetic strategy was applied to the synthesis of a variety of designed balanol analogues for biological evaluation. - Keywords: antitumor agents, balanol, enzyme inhibitor, natural product, total synthesis
