title: Biomimetic synthesis and HPLC-ECD analysis of the isomers of dracocephins A and B.
abstract: Starting from racemic naringenin ((±)-1), a mixture of dracocephin A stereoisomers 6-(2"-pyrrolidinone-5"-yl)naringenin (±)-2a-dand its regioisomer, dracocephin B 8-(2"-pyrrolidinone-5"-yl)naringenin (±)-3a-doriginally isolated fromDracocephalum rupestre, have been synthesized in a one-pot reaction. The separation of2a-dand3a-dwas achieved by preparative HPLC. The four stereoisomers of each natural product were separated by analytical chiral HPLC and their absolute configuration was studied by the combination of HPLC-ECD measurements and TDDFT-ECD calculations. The synthesized flavonoid alkaloids were further characterized by physicochemical and in vitro pharmacological studies.
authors.affiliation: Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary.
authors.forename: Viktor
authors.initials: V
authors.lastname: Ilkei
authors.affiliation: Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Spaits
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Anita
authors.initials: A
authors.lastname: Prechl
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Áron
authors.initials: Á
authors.lastname: Szigetvári
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Béni
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Miklós
authors.initials: M
authors.lastname: Dékány
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Csaba
authors.initials: C
authors.lastname: Szántay
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Judit
authors.initials: J
authors.lastname: Müller
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: Árpád
authors.initials: Á
authors.lastname: Könczöl
authors.affiliation: Department of Organic Chemistry, University of Debrecen, P. O. Box 400, H-4002 Debrecen, Hungary.
authors.forename: Ádám
authors.initials: Á
authors.lastname: Szappanos
authors.affiliation: Department of Organic Chemistry, University of Debrecen, P. O. Box 400, H-4002 Debrecen, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Mándi
authors.affiliation: Department of Organic Chemistry, University of Debrecen, P. O. Box 400, H-4002 Debrecen, Hungary.
authors.forename: Sándor
authors.initials: S
authors.lastname: Antus
authors.affiliation: Department of Medical Microbiology and Immunobiology, University of Szeged, Dóm tér 9, H-6720 Szeged, Hungary; Permanent address: Synthetic Systems Biology Unit, Institute of Biochemistry, Biological Research Centre, Temesvári krt. 62, H-6726 Szeged, Hungary.
authors.forename: Ana
authors.initials: A
authors.lastname: Martins
authors.affiliation: Institute of Pharmacognosy, Faculty of Pharmacy, University of Szeged, Eötvös utca 6, H-6720 Szeged, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Hunyadi
authors.affiliation: Gedeon Richter Plc., Gyömrői út 19-21, H-1103 Budapest, Hungary.
authors.forename: György Tibor
authors.initials: GT
authors.lastname: Balogh
authors.affiliation: Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary.
authors.forename: György
authors.initials: G
authors.lastname: Kalaus
authors.affiliation: Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary.
authors.forename: Hedvig
authors.initials: H
authors.lastname: Bölcskei
authors.affiliation: Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Hazai
authors.affiliation: Department of Organic Chemistry, University of Debrecen, P. O. Box 400, H-4002 Debrecen, Hungary.
authors.forename: Tibor
authors.initials: T
authors.lastname: Kurtán
keywords: Dracocephalum rupestre; ECD calculation; HPLC–ECD; absolute configuration; dracocephins A–B; flavonoid alkaloids