title: Crystal structure of methyl (3RS,4SR,4aRS,11aRS,11bSR)-5-oxo-3,4,4a,5,7,8,9,10,11,11a-deca-hydro-3,11b-ep-oxy-azepino[2,1-a]iso-indole-4-carboxyl-ate.
abstract: The title compound, C15H19NO4, is the a product of the esterification of the corresponding carbonic acid with methanol. The mol-ecule comprises a fused tetra-cyclic system containing three five-membered rings (2-pyrrolidinone, tetra-hydro-furan and di-hydro-furan) and one seven-membered ring (azepane). The five-membered rings have the usual envelope conformations, with the quaternary C atom being the flap atom for the 2-pyrrolidinone ring, and the ether O atom being the common flap atom for the remaining rings. The seven-membered azepane ring adopts a chair conformation with the methine and middle methyl-ene C atoms lying above and below the mean plane defined by the remaining five atoms. The carboxyl-ate substituent is rotated by 77.56 (5)° with respect to the base plane of the tetra-hydro-furan ring. In the crystal, the mol-ecules are bound by weak C-H⋯O hydrogen-bonding inter-actions into puckered layers parallel to (001).
authors.affiliation: Department of Chemistry, University of Douala, Faculty of Sciences, PO Box 24157, Douala, Republic of Cameroon.
authors.forename: Flavien A A
authors.initials: FA
authors.lastname: Toze
authors.affiliation: Department of Organic Chemistry, Peoples' Friendship University of Russia, 6 Miklukho-Maklay St, Moscow 117198, Russian Federation.
authors.forename: Dmitry S
authors.initials: DS
authors.lastname: Poplevin
authors.affiliation: Department of Organic Chemistry, Peoples' Friendship University of Russia, 6 Miklukho-Maklay St, Moscow 117198, Russian Federation.
authors.forename: Fedor I
authors.initials: FI
authors.lastname: Zubkov
authors.affiliation: Department of Organic Chemistry, Peoples' Friendship University of Russia, 6 Miklukho-Maklay St, Moscow 117198, Russian Federation.
authors.forename: Eugeniya V
authors.initials: EV
authors.lastname: Nikitina
authors.affiliation: Department of Chemistry & Biology, New Mexico Highlands University, 803 University Ave, Las Vegas, NM 87701, USA.
authors.forename: Ciara
authors.initials: C
authors.lastname: Porras
authors.affiliation: Department of Chemistry & Biology, New Mexico Highlands University, 803 University Ave, Las Vegas, NM 87701, USA ; Department of Inorganic Chemistry, Peoples' Friendship University of Russia, 6 Miklukho-Maklay St, Moscow 117198, Russian Federation.
authors.forename: Victor N
authors.initials: VN
authors.lastname: Khrustalev
keywords: 3,6a-ep­oxy­iso­indoles; C—H⋯O hydrogen bonds; azepane; crystal structure; intra­molecular cyclo­addition