Anthocyanins from flowers of Crocus (Iridaceae)

The perianth segments of three cultivars of Crocus were investigated by HPLC for their content of anthocyanins. The investigation revealed the presence of four known and two new anthocyanins. The novel anthocyanins were isolated from the blue flowers of C. chrysanthus 'Skyline', and identified as petunidin 3-O-(6-O-malonyl-beta-D-glucoside)-7-O-(6-O-malonyl-beta-D-glucoside) and malvidin 3-O-(6-O-malonyl-beta-D-glucoside)-7-O-(6-O-malonyl-beta-D-glucoside). The anthocyanins, isolated from the blue flowers of C. sieberi ssp. sublimis 'Tricolor', were identified as 3,5-beta-D-diglucosides of delphinidin and petunidin, and from C. chrysanthus 'Eyecatcher' were as their 3-beta-rutinosides. The complete structural determination of each compound was achieved by use of 1D and 2D NMR techniques and other spectral evidence. (C) 1998 Elsevier Science Ltd. All rights reserved.