Design, synthesis and structure–activity relationships of a series of 9-substituted adenine derivatives as selective phosphodiesterase type-4 inhibitors
Adenine derivatives substituted in position 9 have been demonstrated to have potent cyclic nucleotide phosphodiesterase (PDE) inhibition properties with high selectivity toward PDE-4. Starting from our initial lead compound 9-(2-fluorobenzyl)-N(6)-methyl-2-trifluoromethyladenine (4, NCS613), we designed and synthesized a new series of 9-substituted derivatives for developing structure-activity relationship
Exo-Selective Diels−Alder Reactions of Vinylazepines. Origin of Divergent Stereoselectivity in Diels−Alder Reactions of Vinylazepines, Vinylpiperideines, and Vinylcycloalkenes
作者:Brant Boren、Jennifer S. Hirschi、Joseph H. Reibenspies、Matthew D. Tallant、Daniel A. Singleton、Gary A. Sulikowski
DOI:10.1021/jo034462h
日期:2003.11.1
Diels-Alderreactions of vinylazepines with N-phenylmaleimide afforded exclusively the exo cycloadduct, while high endo stereoselectivity was observed, as previously reported, in analogous reactions of vinylpiperideines. This curious contrast was confirmed by X-ray analysis of cycloadducts not susceptible to epimerization. The stereoselectivity of Diels-Alderreactions of vinylazepines, vinylpiperideines