Total Synthesis of (+)-Frondosin A. Application of the Ru-Catalyzed [5+2] Cycloaddition
摘要:
The first total synthesis of (+)-frondosin A was accomplished in 19 longest linear and 21 total steps from commercially available materials. The key features of the synthesis include a Ru-catalyzed [5+2] cycloaddition, a Claisen rearrangement, and a ring expansion to construct the core of the frondosin A in a diastereoselective and regioselective fashion. This is the first application of a Ru-catalyzed [5+2] cycloaddition in the total synthesis of a natural product. Through this synthesis, the absolute configuration of (+)-frondosin A was established.
An Ester Enolate–Claisen Rearrangement Route to Substituted 4-Alkylideneprolines. Studies toward a Definitive Structural Revision of Lucentamycin A
作者:Sujeewa Ranatunga、Jinsoo S. Kim、Ujjwal Pal、Juan R. Del Valle
DOI:10.1021/jo201727g
日期:2011.11.4
substituted α-allylglycine products with good to excellent diastereoselectivities. Resolution of dipeptide diastereomers and cyclization to form the pyrrolidine rings provide rapid access to stereopure prolyl dipeptides. We have applied this strategy to the synthesis of four Emp-containing isomers of lucentamycin A in pursuit of a definitive stereochemical revision of the naturalproduct. Our studies indicate
Total Synthesis of (+)-Frondosin A. Application of the Ru-Catalyzed [5+2] Cycloaddition
作者:Barry M. Trost、Yimin Hu、Daniel B. Horne
DOI:10.1021/ja073272b
日期:2007.9.1
The first total synthesis of (+)-frondosin A was accomplished in 19 longest linear and 21 total steps from commercially available materials. The key features of the synthesis include a Ru-catalyzed [5+2] cycloaddition, a Claisen rearrangement, and a ring expansion to construct the core of the frondosin A in a diastereoselective and regioselective fashion. This is the first application of a Ru-catalyzed [5+2] cycloaddition in the total synthesis of a natural product. Through this synthesis, the absolute configuration of (+)-frondosin A was established.
An approach toward the total synthesis of subergorgic acid
作者:John C. Gilbert、Jiandong Yin
DOI:10.1016/j.tet.2008.04.005
日期:2008.6
Ireland–Claisenrearrangement of a substituted alkenyl cyclopentanecarboxylate provided a monocyclic isomer containing the proper stereochemistry for four of the five stereogenic centers in subergorgic acid. Efforts to construct the additional rings in the molecule were thwarted as a result of steric and other factors. The results provide insights regarding the Ireland–Claisenrearrangement in five-membered