ABSTRACT
A solution to the long-standing problem presented by the oxidative cyclization of a phenolic 3-arylpropionamide to a spirolactam has been developed in this laboratory via oxazoline chemistry. This research was motivated by our interest in some novel tricyclic azaspirane natural products formally derived from tyrosine, such as FR901483 and TAN1251C. In this paper, we disclose full details of the total synthesis of these substances.
Subject(s)
Immunosuppressive Agents/chemical synthesis , Organophosphorus Compounds/chemical synthesis , Aza Compounds/chemical synthesis , Spiro Compounds/chemical synthesisABSTRACT
[structure: see text]. The total synthesis of FR901483, a structurally novel immunosuppressant, has been accomplished by the use of technology recently developed in this laboratory for the oxidative cyclization of phenolic oxazolines to spirolactams. Our approach may reflect the biosynthetic pathway leading to the natural product.
Subject(s)
Immunosuppressive Agents/chemical synthesis , Organophosphorus Compounds/chemical synthesis , Cyclization , Fungi/chemistry , Oxidation-ReductionABSTRACT
The oxidative cyclization of a phenolic amide to a spirolactam has long been regarded as an "impossible" reaction, because exposure of the substrates to a variety of oxidants results in formation of spirolactones with consequent loss of the amine segment. We recently communicated that this heretofore unknown transformation may be achieved by oxidation of oxazoline analogues of phenolic and indolic amides. Herein, we provide full details of our work.
