Isolation and structure elucidation of pyridine alkaloids from the aerial parts of the Mongolian medicinal plant Caryopteris mongolica Bunge.

The seven pyridine alkaloids 1-7, the flavonoid acacetin (8), and L-proline anhydride (9) have been isolated from the aerial parts of the Mongolian medicinal plant Caryopteris mongolica Bunge. The structures of the natural products 1-9 have been assigned by MS, as well as IR, 1D NMR (H, C, DEPT), and 2D NMR (COSY, HSQC, HMBC, NOESY) spectroscopic methods. The compounds 2 and 4-7 represent new chemical structures.

The effect of organic matter humification (aromaticity and oxidation degree) on structural and nanomorphological characteristics of humic nanocomposites of metallic platinum.

Background: It has been previously found that humic substances (HSs) can serve as the environmentally benign non-toxic agent for the preparation of magnetic and noble metals nanoparticles that are increasingly used in biomedicine. The structure of HSs and, hence, their synthetic potential depend on the source of their origin. Thus, humification character, determined by conditions and duration of complex transformation of organic remains in HSs can evidence their structure, in particular their aromaticity and oxidation degree.