Synthesis of 5-aminolevulinic acid (ALA) and itst-butyl ester for the fluorescence detection of early cancer

New diketopiperazine alkaloid and polyketides from marine-derived fungus Penicillium sp. TW58-16 with antibacterial activity against Helicobacter pylori

Marine-derived fungi can usually produce structurally novel and biologically potent metabolites. In this study, a new diketopiperazine alkaloid (1) and two new polyketides (10 and 11), along with 8 known diketopiperazine alkaloids (2-9) were isolated from marine-derived fungus Penicillium sp. TW58-16. Their structures were fully elucidated by analyzing UV, IR, HR-ESI-MS, 1D, and 2D NMR spectroscopic data. The absolute configurations of the new compounds 1, 10 and 11 were ascertained by X-ray diffraction (Cu Kα radiation) and comparing their CD data with those reported. In addition, the antibacterial activities of these compounds against Helicobacter pylori in vitro were assessed. Results showed that compounds 3, 6, 8 and 9 displayed moderate antibacterial activity against standard strains and drug-resistant clinical isolates of H. pylori in vitro. This result demonstrates that diketopiperazine alkaloids could be lead compounds to be explored for the treatment of H. pylori infection.

[Physico-biological foundation of skin fluorescence--review]

Fluorescence is a peculiar aspect of photoluminescence. Some intrinsic components of the skin are fluorophores. Other synthetic components are metabolized into fluorophores. These characteristics may be used for identifying some specific aspects of skin physiopathology. Recent technological evolution has provided new devices bringing sensitive and specific information from the skin. This review presents a synthesis of the progress made in the field of fluorescence and specular reflexion of incident UV light on the skin.