title: 6,7,8,9-Tetrahydro-3-methyl-1H-pyrano-[4,3-b]quinolin-1-one.
abstract: The condensation reaction of 4-amino-6-methyl-2-pyrone with 1-cyclohexenecarboxaldehyde and a catalytic amount of (S)-(+)-10-camphorsulfonic acid in toluene at 358 K gave a 1:2.5 ratio of the title compound, (1) (C13H13NO2), and 7,8,9,10-tetrahydro-1H-pyrano[4,3-c]isoquinoline-1-one, (2). The formation of (2) presumably proceeds through an intermediate imine. Both (1) and (2) show inhibitory activities against acetylcholinesterase and human aldose reductase. Of the three linear-fused rings of (1), both ring A and ring B are planar and the angle between these planes is 0.46 (13) degrees. While the two C atoms of cyclohexane ring C attached to its common atoms with ring B are in the plane of the latter, as expected, the remaining two C atoms of ring C are out of this plane, by 0.342 (4) and -0.402 (3) A, respectively.
authors.affiliation: Department of Chemistry, Kansas State University, Manhattan 66506, USA.
authors.forename: D H
authors.initials: DH
authors.lastname: Hua
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.forename: H S
authors.initials: HS
authors.lastname: Sin
authors.forename: P D
authors.initials: PD
authors.lastname: Robinson
authors.forename: C Y
authors.initials: CY
authors.lastname: Meyers
authors.forename: E M
authors.initials: EM
authors.lastname: Perchellet
authors.forename: J P
authors.initials: JP
authors.lastname: Perchellet
authors.forename: P K
authors.initials: PK
authors.lastname: Chiang
authors.forename: J F
authors.initials: JF
authors.lastname: Biellmann
mesh_terms: D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors; D002800:Cholinesterase Inhibitors / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry*; D006801:Humans; D015394:Molecular Structure; D011714:Pyrans / Q000737:chemistry*; D011804:Quinolines / Q000737:chemistry*
chemical_list: C402962:6,7,8,9-tetrahydro-3-methyl-1H-pyrano-(4,3-b)quinolin-1-one; D002800:Cholinesterase Inhibitors; D004791:Enzyme Inhibitors; D011714:Pyrans; D011804:Quinolines; D000449:Aldehyde Reductase