Glycosides Scilla

Gobmoh [67] has employed ethyl acetate-methanol (95 + 5), methyl ethyl ketone-toluene-methanol-acetic acid-water (80 +10 + 5 + 2 + 6) and ethyl acetate-chloroform (90 + 10) on silica gel G for Scilla glycosides and Steidlb [161, 162] has used butanone, saturated with water, on silica gel G, separating into zones, re-chromatographing with simitar... 

Types of Cardiac Glycoside. Three groups of plants produce cardenolides the Digitalis species, growing in temperate climates the Strophanthus species, of tropical provenance and Scilla (sea onion or squill), a Mediterranean plant. 

Scillae buibus var. alba (3-5). The white squill samples (3,4) contain predominantly pro.scillaridin, seen as a major light-brown fluorescent zone at R, 0.6 (T/a). The glycoside scillaren A (R, — 0.4/b) dominates the standardized commercial extract 5. Three additional cardenolide zones (e.g. glucoscUlaren R, — 0.2) are detectable as yellow-browii fluorescent zones. Sciliirosidin glycosides are absent in white squill. 

Scillaren. A mixture of glycosides, scillaren A and B in the proportions in which they occur in fresh squill, Ur-ginea Scilla) maritime (L.) Baker, Liliaceue, about 2 parts of A to I part of B. Isolation of scillaren and separation of A and B Stoll et al.. Helv. Cfurn. Acta 16, 703 (1933). 

Some Schilloideae plants, such as Urginea scilla are well known to contain cardiac glycosides. We have studied 21 species of this subfamily and isolated many kinds of steroidal glycosides, but have not found any cardiac glycoside. 

Scilla peruviana occrred in Portugal and North Afiica contained novel triterpene glycosides (31-32)with a rearranged carbon skeleton in which C-24 to C-27 side chain is transfered to C-22position ... 

The homoisoflavanones belong to a small family of natural products whose first member was isolated by Boehler and Tamm in 1967 from bulbs of Eucomis bicolor Bak. (9). Their discovery resulted from a systematic chemical analysis of Liliaceae for cardiac glycosides. However, unlike the botanically closely related Urginea maritima (L.) Bak. (Squill) and some species of Scilla, Ornithogalum and Dipcadi 33), Eucomis plants did not contain even traces of these compounds. 

Isol. from the partial acid hydrolysate of glycosides from Scilla maritima constit. in the repeating unit of the capsular antigen of Klebsiella K55. 

Cardiac glycosides occur in several famihes of higher plants, e.g., Liliaceae, Ranunculaceae, Asclepiadaceae, Apocynaceae, and Scrophulariaceae. Cardeno-lides are the most widespread derivatives. Bufadienolides have been isolated from only a few genera, e.g., Scilla (Liliaceae) and Helleborus (Ranunculaceae). In addition cardenolides are synthesized in certain beetles and bufadienolides in toads Bufo sp.). The cardenolides found in the locust Poekilocerus bufonius the butterfly Danaus plexippus and several other animals are derived from cardiac glycosides taken up with the diet (E 5.1). 

D-Glucopyranosyl-ij rhamnose (sciUabiose). Phenylosazone, m.p. 165° C. obtained from a glycoside isolated from Scilla maritima L. Complete hydrolysis gives D-glucose and L-rhamnose (128). 

Further investigations on red cells have confirmed these views (Fig. 1). Scilla-ren A is the most powerful inhibitory compound, being effective on Na and K transport at concentrations as low as 10 M. Its activity is 2unsaturated glycoside this substantiates the idea that an active glycoside must possess an unsaturated resonant ring, partly electrophilic in character. The same molecular features have been shown to be necessary for cardiotonic action. 

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