title: Diversity-oriented synthetic approach to naturally abundant S-amino acid based benzannulated enantiomerically pure medium ring heterocyclic scaffolds employing inter- and intramolecular mitsunobu reactions.
abstract: The diversity-oriented organic synthesis of enantiomerically pure benzannulated oxazepine, diazepine, thiazepine, oxazocine, and diazocine scaffolds is described from easily accessible naturally occurring S-amino acids as chiral synthons. Inter- and intramolecular Mitsunobu reactions for the formation of carbon-nitrogen, carbon-oxygen, and carbon-sulfur bonds have been used as key transformations to construct these biologically important privileged heterocycles. This is the first example where the Mitsunobu approach has been utilized for the construction of S-amino acid based seven- and eight-membered ring systems.
authors.affiliation: Medicinal and Process Chemistry Division, Central Drug Research Institute, Lucknow-226001, UP, India.
authors.forename: Jitendra Kumar
authors.initials: JK
authors.lastname: Mishra
authors.forename: Gautam
authors.initials: G
authors.lastname: Panda
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D006571:Heterocyclic Compounds