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Three known phloroglucinols (japonicine A, uliginosin A and isouliginosin B) and a new phloroglucinol (hyperbrasilol A) have been isolated from a petrol extract of the leaves and flowers of Hypericum brasiliense. Their structures were established by spectroscopic methods (UV, DCI-MS, 1H and 13C NMR, including SINEPT, HMBC, HSQC, DQFCOSY experiments). The substitution pattern of hyperbrasilol A was confirmed by X-ray crystallography. All four phloroglucinols were antibacterial against Bacillus subtilis in a TLC bioautographic assay. The flavonoids, kaempferol, luteolin, quercetin, quercitrin, isoquercitrin, hyperoside and guaijaverin, were isolated from a methanol extract of the same organs.

Three new meroterpenoid naphthoquinones, the known cordiaquinone B and a new naphthoxirene have been isolated from the roots of Cordia linnaei. Their structures were established by spectrometric methods including EI, D/CI and FAB mass spectrometry, 1H, 13C and 2D NMR experiments. The naphthoquinones showed activity against Cladosporium cucumerinum, Candida albicans and the larvae of the yellow fever-transmitting mosquito Aedes aegypti, while the naphthoxirene derivative was found to be inactive in the same bioassays.

In addition to the known cordiaquinones A and B, two novel meroterpenoid naphthoquinones, named cordiaquinones J and K, have been isolated from the roots of Cordia curassavica. Their structures were elucidated by spectrometric methods including EI, D/CI mass spectrometry, 1H, 13C and 2D-NMR experiments. The four naphthoquinones demonstrated antifungal activities against Cladosporium cucumerinum, Candida albicans and toxic properties against larvae of the yellow fever-transmitting mosquito Aedes aegypti.

Chromatography is the lynchpin of phytochemistry and is the key to obtaining pure compounds for structure elucidation, for pharmacological testing or for development into therapeuticals. It also plays a fundamental role as an analytical technique for quality control and standardisation of phytotherapeuticals. Although liquid chromatography is barely 100 years old, an extraordinary variety of instrumental and ancillary equipment is available, notably in the domain of high-performance liquid chromatography. It is impossible to touch all areas of chromatography in such a review but certain areas are worthy of mention: HPLC, HPTLC, UPLC and countercurrent chromatography. Another important addition has been the development of hyphenated techniques involving HPLC: LC/UV, LC/MS, LC/MS(n) and LC/NMR. These are indispensable nowadays for the early detection and identification of compounds in crude plant extracts.