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Four previously unreported triterpenoid saponins named 3β-hydroxy-23-oxours-12-en-28-oic acid 28- O -β- D -glucopyranosyl ester (mannioside G) ( 1 ), 23- O -acetyl-3β-hydroxyurs-12-en-28-oic acid 28- O -β- D -glucopyranosyl ester (mannioside H) ( 2 ), ursolic acid 28- O -[α- L -rhamnopyranosyl-(1→4)-β- D -glucopyranosyl-(1→6)-β- D -glucopyranosyl] ester (mannioside I) ( 3 ), and 3β-hydroxy-23-oxolup-20(29)-en-28-oic acid 28- O -β- D -glucopyranosyl ester (mannioside J) ( 4 ) were isolated as minor constituents from the EtOAc soluble fraction of the MeOH extract of the leaves of Schefflera mannii along with the known compounds 23-hydroxyursolic acid 28- O -β- D -glucopyranosyl ester ( 5 ), ursolic acid 28- O -β- D -glucopyranosyl ester ( 6 ), pulsatimmoside B ( 7 ) betulinic acid 28- O -[α- L -rhamnopyranosyl-(1→4)-β- D -glucopyranosyl-(1→6)-β- D -glucopyranosyl] ester ( 8 ), 23-hydroxy-3-oxo-urs-12-en-28-oic acid ( 9 ), hederagenin ( 10 ), ursolic acid ( 11 ), betulinic acid ( 12 ), and lupeol ( 13 ). Their structures were elucidated by a combination of 1D and 2D NMR analysis and mass spectrometry. The MeOH extract, the EtOAc and n -BuOH fractions, and some of the isolated compounds were evaluated for their antibacterial activity against four bacteria: Staphylococcus aureus ATCC1026, Staphylococcus epidermidis ATCC 35984, Escherichia coli ATCC10536, and Klepsiella pnemoniae ATCC13882. They were also screened for their antioxidant properties, but no significant results were obtained.

Microbial infections are leading causes of death and morbidity all over the world due to the development of the resistance to antibiotics by certain microorganisms. In this study, the chemical exploration of the ethanol (EtOH) extract of the aerial part of Dracaena stedneuri (Dracaenaceae) led to the isolation of one previously unreported chalcone derivative, i.e., 2',4'-dihydroxy-2,3'-dimethoxychalcone ( 1 ), together with 12 known compounds: 8-( C )-methylquercetagetin-3,6,3'-trimethyl ether ( 2 ), methylgalangine ( 3 ), quercetin ( 4 ), kaempferol ( 5 ), 6,8-dimethylchrysin ( 6 ), ombuine-3- O -rutinoside (4',7-dimethylquercetin-3- O - α -L-rhamnopyranosyl-(1 → 6) - β -D-glucopyranoside) ( 7 ), alliospiroside A ( 8 ), β -sitosterol 3- O -glucopyranoside ( 9 ), ishigoside ( 10 ), betulinic acid ( 11 ), oleanolic acid ( 12 ), and lupeol ( 13 ). The structures were determined by spectroscopic and spectrometric analysis including 1- and 2-Dimensional Nuclear Magnetic Resonance (1D- and 2D-NMR), High-Resolution Electrospray Ionization Mass Spectrometry (HRESIMS), and comparison with literature data. The isolated secondary metabolites and crude extract displayed antibacterial activity against some multidrug-resistant strains with minimal inhibitory concentration (MIC) values ranging from 32 to 256 μg/mL. The antibacterial activity of compound 13 against Enterobacter aerogenes ATCC13048 (MIC value: 32 μg/mL) was higher than that of chloramphenicol used as the reference drug (MIC = 64 μg/mL).