Skeletal and appendage diversity as design elements in the synthesis of a discovery library of nonaromatic polycyclic 5-iminooxazolidin-2-ones, hydantoins, and acylureas
Amino-acid derived cross-conjuggated trienes were used as a starting point for the synthesis of a discovery library of over 200 polycyclic 5-iminooxazolidin-2-ones, hydantoins, and acylureas. The main feature of this library synthesis is a triple branching strategy, which provides efficient access to five skeletally diverse scaffolds. In addition, four sets of building blocks were applied in both a front end and a back end diversification strategy. Multiple fused rings were obtained by cyclization of diamides with phosgene and stereoselective Diels-Aider reactions with maleimides. The 5-iminooxazolidin-2-one scaffold was rearranged into the isomeric hydantoin scaffold through a sequence of ring-opening and ring-closing reactions. (C) 2008 Elsevier Ltd. All rights reserved.
Rhodium(I)-Catalyzed Allenic Carbocyclization Reaction Affording δ- and ε-Lactams
作者:Kay M. Brummond、Thomas O. Painter、Donald A. Probst、Branko Mitasev
DOI:10.1021/ol062842u
日期:2007.1.1
This letter extends the scope of the rhodium(I)-catalyzedallenic Alder-ene carbocyclization reaction to the preparation of delta- and epsilon-lactams from amides. A variety of allenic propiolamides were cycloisomerized to give a number of unsaturated delta-lactams. In addition, allenic propargylamides give good yields of the corresponding epsilon-lactams. Formation of lactams possessing these ring
Cycloaddition Reactions of Amino-Acid Derived Cross-Conjugated Trienes: Stereoselective Synthesis of Novel Heterocyclic Scaffolds
作者:Kay M. Brummond、Branko Mitasev、Bingli Yan
DOI:10.3987/com-06-s(w)36
日期:——
obtained via a Rh(I)-catalyzed allenic Alder-ene reaction represent a new class of compounds. The synthesis of heterocyclic compounds containing multiple fused rings was accomplished via sequential Diels-Alder reactions of amino-acid derived cross-conjugated trienes. Newly synthesized imino-oxazolidinone fused trienes were used to control the stereoselectivity in an intermolecular cycloaddition sequence