Crystal structure, Hirshfeld surface analysis and DFT studies of 2-(2,3-di-hydro-1H-perimidin-2-yl)phenol.

The asymmetric unit of the title compound, C17H14N2O, contains two independent mol-ecules each consisting of perimidine and phenol units. The tricyclic perimidine units contain naphthalene ring systems and non-planar C4N2 rings adopting envelope conformations with the C atoms of the NCN groups hinged by 44.11 (7) and 48.50 (6)° with respect to the best planes of the other five atoms. Intra-molecular O-H⋯N hydrogen bonds may help to consolidate the mol-ecular conformations. The two independent mol-ecules are linked through an N-H⋯O hydrogen bond. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (52.9%) and H⋯C/C⋯H (39.5%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Density functional theory (DFT) optimized structures at the B3LYP/ 6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

Chemical findings and in vitro biological studies to uphold the use of Ficus exasperata Vahl leaf and stem bark.

Ficus exasperata Vahl, commonly known as sandpaper, is a terrestrial Afro-tropical tree used in popular medicine. Despite the existence of some works on the biological activities of this species, its chemical composition is still poorly known. The aim of this study was to extend the knowledge on the phytochemistry and biological properties of this species. Aqueous extracts from F. exasperata leaves and stem bark were analysed. Thirty-one phenolic compounds, comprising cinnamoyl derivatives, flavonoid-O-glycosides, flavonoid-mono-C-glycosides, flavonoid-di-C-glycosides and one furanocoumarin, were determined by HPLC-DAD-ESI/MSn and UPLC-ESI-QTOF-MS, 26 of them being reported for the first time in this species. The profile of organic acids, characterized by HPLC-UV, was also reported for the first time. The best radical scavenging activity was observed for the aqueous extract from leaves (IC50 values of 222.5, 510.0 and 50.0 µg/mL against DPPH•, •NO and O2•-, respectively). In addition, both aqueous extracts of the leaves and stem bark displayed a weak effect on α-amylase, and no cytotoxicity against gastric adenocarcinoma cell line, AGS. This study contributes to the valorisation of these vegetal materials, which may have application in functional foods and/or nutraceuticals.