Multigene evidence reveals the systematic position of Pleurocladopsis simulans (C. Massal.) R. M. Schust. within Schistochila Dumort., Schistochilaceae

The monotypic Pleurocladopsis, endemic to Chile, was established by Schuster in 1964 based on an earlier poorly known species Cephalozia (?) simulans C. Massal. The phylogenetic position of Pleurocladopsis simulans had been considered uncertain until it was placed in the family Schistochilaceae on account of the gynoecial and sporophytic characters. It has been assumed that Pleurocladopsis represents the starting point of evolution in Schistochilaceae. In the present study, the phylogenetic position and taxonomic status of Pleurocladopsis simulans are inferred from phylogenetic analysis of three chloroplast DNA sequence data. The result suggests that the genus was established solely based on the autapomorphic characters, thus obscuring its actual phylogenetic relationship with Schistochila and that these characters are later derived rather than ancestral. The result also confirms that the gynoecial and sporophytic characters are important in taxonomy, but they may be not sufficient at the infrafamilial level and at other lower taxonomic levels. In accordance with the results of the present study, Pleurocladopsis is synonymised with Schistochila, and the new combination Schistochila simulans (C. Massal.) Xiao L. He & Yu Sun is made.Peer reviewe

Synthesis of Regioselectively Acylated Quercetin Analogues with Improved Antiplatelet Activity

The aim of the present study was to report on a complete synthetic approach, namely benzylation-hydrolysis-acylation-hydrogenation, to the synthesis of regioselectively acylated quercetin analogues using low-cost rutin as a starting material. Three quercetin analogues, quercetin-3-O-propionate (Q-pr), quercetin-3-O-butyrate (Q-bu) and quercetin-3-O-valerate (Q-va), containing 3-, 4- and 5-carbon aliphatic acyl chains, respectively, were synthesized and characterized with 1H nuclear magnetic resonance (NMR), 13C NMR and mass spectrometry. Compared with quercetin, all three analogues exhibited improved lipophilicity. The lipophilicity of the analogue increased with increasing acyl chain length. Q-va exhibited the highest lipophilicity among the three analogues, but a lower water solubility compared with quercetin. By contrast, Q-pr and Q-bu exhibited 8.2- and 4.7-fold higher water solubility compared with quercetin, respectively. The in vitro and in vivo studies demonstrated that Q-pr and Q-bu were more effective whereas Q-va was less effective in inhibiting platelet aggregation compared with quercetin. These results indicated that the water solubility and the lipophilicity of the analogues must be improved in order to achieve higher antiplatelet activity, and an optimal acyl chain length is crucial for the synthesized quercetin analogues to be more effective