Nuphar rhizome

Nupharjaponicum (Nymphaeaceae) is a perennial herb that grows in shallow running water. The rhizome is called Nuphar rhizome (Kohone) and is used in complementary male fertility medicines and in women s diseases. 

As chemical components of Nuphar rhizome, several sesquiterpene alkaloids, such as nupharidine, (—)-nupharamine, and (-)-deoxynupharidine are known [l-4].Among them, the absolute configuration of (—)-nupharamine was decided by converting (—)-deoxynupharidine [5-7]into (-)-nuphara-mine [8].The racemic (—)-deoxynupharidine was synthesized [9]. 

Similar nonalkaloidal classes of compounds were isolated from Nuphar lutea thus, the presence of fraws-cinnamic, arachidic, behenic, and palmitic acids was confirmed in rhizomes (27) and that of ellagic, caffeic, p-coumaric, sinapic, and... 

Alkaloids were first detected in these plants by Dragendorff (J), who found them in 1879 in the rhizome of N. luteum. Soon thereafter Griining 2) isolated nupharine, an amorphous alkaloid to which he ascribed the formula C18H24O2N2. Not until 40 years later did Arima and Takahashi (3) obtain from Nuphar japonicum another alkaloid, which had the formula C15H23O2N and which they named nupharidine. In 1943 Kotake et al. isolated another alkaloid, deoxynupharidine, C15H23ON. 

The rhizomes of Nuphar japonicum and N. luteum (Nymphaeaceae) contain sesquiterpene-derived alkaloids that possess a quinolizidine nucleus (Howard and Michael, 1986). These compounds are based on a C15 skeleton of which part has been elaborated into a 3-substituted furan (Howard and Michael, 1986) (Fig. 36.4). 

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