title: A complete gear system in N-benzoyl-carbazole derivatives.
abstract: 2',6'-Disubstituted N-benzoylated carbazole derivatives were found to exhibit atropisomerism. The bulky substituents restricted rotation about the N-C7' and C7'-C1' bonds to separate four atropisomers, in which rotation about the C7'-C1' bond was in perfect concert with rotation about the N-C7' bond. Complete geared rotation without slippage at 37 °C for 7 days was observed for the first time. Conformational analysis clarified the preference for the gear system over other internal conversion pathways.
authors.affiliation: Faculty of Pharma Sciences, Teikyo University , 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan.
authors.forename: Hidetsugu
authors.initials: H
authors.lastname: Tabata
authors.forename: Susumu
authors.initials: S
authors.lastname: Kayama
authors.forename: Yuka
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Norihiko
authors.initials: N
authors.lastname: Tani
authors.forename: Shintaro
authors.initials: S
authors.lastname: Wakamatsu
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Tasaka
authors.forename: Tetsuta
authors.initials: T
authors.lastname: Oshitari
authors.forename: Hideaki
authors.initials: H
authors.lastname: Natsugari
authors.forename: Hideyo
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D002227:Carbazoles / Q000737:chemistry*; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D002227:Carbazoles