have developed a novel synthetic route to nitrogen-containing heterocycles via radical addition–ionic cyclization reaction. Treatment of oxime ethers carrying the tosyloxy group with Et3B and alkyl iodide in the presence of Lewis acid gave the substituted pyrrolidines and piperidines. The reaction of oxime ethers carrying the methoxycarbonyl group proceeded under the same conditions to give the amino
Total Synthesis of Pyrrolidine and Piperidine Natural Products via TMSOTf-Mediated “5/6-<i>endo-dig</i>” Reductive Hydroamination of Enynyl Amines
作者:Santosh J. Gharpure、Raj K. Patel、Krishna S. Gupta
DOI:10.1021/acs.orglett.3c02115
日期:2023.8.11
acid-mediated 5/6-endo-dig reductive hydroamination cascade of enynyl amines. The brevity of the developed strategy allowed for the collective stereoselective totalsynthesis of various alkaloids, including (±)-pyrrolidine cis-225H, (±)-epi-197B, (±)-epi-225C, the family of (+)-solenopsins and (+)-isosolenopsins, and the formal synthesis of (±)-bgugaine and (+)-azimic acid.
Design and synthesis of conformationally constrained 3-(N-alkylamino)propylphosphonic acids as potent agonists of sphingosine-1-phosphate (S1P) receptors
作者:Lin Yan、Jeffrey J. Hale、Christopher L. Lynch、Richard Budhu、Amy Gentry、Sander G. Mills、Richard Hajdu、Carol Ann Keohane、Mark J. Rosenbach、James A. Milligan、Gan-Ju Shei、Gary Chrebet、James Bergstrom、Deborah Card、Hugh Rosen、Suzanne M. Mandala
DOI:10.1016/j.bmcl.2004.07.049
日期:2004.10
A series of conformationallyconstrained 3-(N-alkylamino)propylphosphonic acids were systematically synthesized and their activities as S1P receptoragonists were evaluated. Several pyrrolidine and cyclohexane analogs had S1P receptor profiles comparable to the acyclic lead compound, 3-(N-tetradecylamino)propylphosphonic acid (3), lowered circulating lymphocytes in mice after iv administration and