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15 N NMR data are a suitable and sensitive means for characterizing long-range electronic substituent effects. Additionally, 13 C NMR data for these compounds are presented.

A new betacyanin endogenously occurring in fruits of nine Mammillaria species, i.e., M. roseo-alba (Boedecker), M. donatii (Berge), M. coronata (Scheidweiler), M. karwinskiana (Martius), M. gummifera (Engelmann), M. infernillensis (Craig), M. centricirrha (Lemaire), M. krameri (Muehlenpfordt), and M. magnimamma (Haworth), was studied by means of spectroscopic techniques. The betacyanin was identified as betanidin 5-O-(6'-O-malonyl)-beta-sophoroside for which the trivial name mammillarinin is proposed. In some Mammillaria species this compound was reported as a dominating pig-ment. Except for its epimer, two other isomers of mammillarinin were tentatively identified as betanidin/isobetanidin 5-O-(4'-O-malonyl)-beta-sophoroside present in the fruits as acyl migration products.

Formation of complexes between crown ethers and cyclodextrins has been studied using diffusion measurements. The structures of the complexes have been proposed on the basis of the theoretical calculations and the results obtained. Relation between the structural parameters (rings' diameter and symmetry) and the tendency of molecules' interactions are discussed.