Stereoselective synthesis of (E)- and (Z)-1-azabicyclo[3.1.0]hex-2-ylidene dehydroamino acid derivatives
摘要:
Bromination of dehydroamino acid derivatives with NBS or Br2/2,6-lutidine yields (E)- or (Z)-beta-bromo-dehydroamino acid derivatives selectively. Subsequent intramolecular Michael addition-elimination of an aziridine proceeds with complete retention of olefin geometry to provide the 1-azabicyclo[3.1.0]hex-2-ylidene ring system proposed for the azinomycin series of antitumor antibiotics.
Dehydroamino acid derivatives from D-arabinose and L-serine: synthesis of models for the azinomycin antitumor antibiotics
摘要:
Synthesis of aldehydes 17 from D-arabinose and 31 from L-serine provided key precursors for the generation of highly functionalized dehydroamino acid derivatives upon condensation with glycyl phosphonates. Subsequent bromination and intramolecular addition/elimination afforded the azabicyclo[3.1.0]hex-2-ylidene ring system postulated to exist in the azinomycin antitumor antibiotics.