np9b00655_si_001.pdf (2.82 MB)
Pigments of the Moss Paraleucobryum longifolium: Isolation and Structure Elucidation of Prenyl-Substituted 8,8′-Linked 9,10-Phenanthrenequinone Dimers
journal contribution
posted on 2020-02-20, 12:42 authored by Dezső Csupor, Tibor Kurtán, Martin Vollár, Norbert Kúsz, Katalin E. Kövér, Attila Mándi, Péter Szűcs, Marianna Marschall, Seyyed A. Senobar Tahaei, István Zupkó, Judit HohmannIn a search for new secondary metabolites from mosses, leucobryns
A–E, axially chiral 9,10-phenanthrenequinone dimers, were isolated
from Paraleucobryum longifolium (1–5), together with diosmetin triglycoside. Leucobryns B (2) and C (3) were proved to be homodimeric atropodiastereomers
containing both axial and central chirality elements, while leucobryns
D (4) and E (5) were found to be heterodimeric
atropodiastereomers containing central chirality in only one of the
two monomeric units. Axial chirality of the compounds was determined
by ECD measurements and sTDA ECD calculations, while the central chirality
elements were assigned by TDDFT-SOR calculations. Leucobryns represent
the first 9,10-phenanthrenequinone dimers, the monomers of which are
linked through their C-8 atoms. Leucobryns B–E contain an uncommon
C10 monoterpenoid side chain, in which isoprenoid units
are joined by 3,4 linkages. Leucobryns A and B exhibited weak antiproliferative
activity against several human cancer cell lines.