RESEARCH group knows, b e e n found in nature. T w o other chemists tackled t h e aglycon structure. Erich Mosettig a n d Wil liam R. Ν es found that t h e aglycon also is unusual. It possesses a perhydrop h e n a n t h r e n e skeleton t o which a fivemembered ring is attached, b u t not at the 1,2-positions as in the steroids. T h e ring is analogous t o t h e structures or' t h e diterpenoid hydrocarbons phyllocladene a n d isophyllocladene, as well as t h e diterpenoid alkaloids like t h e Garrya alkaloids veatehine, garryine, cuauchichicine, a n d laurifoline. It ap pears likely that aglucon is a diter penoid acid and as such is remarkable in t h a t it exists i n n a t u r e as a glucoside, which may tentatively be assigned the structure shown ( p a g e 124) . • As α S w e e t e n e r . As a natural product, stevioside might b e attractive as a sweetening agent, particularly if the Government were t o rule against synthetic sweeteners. F o r the present, however, it cannot compete with a cheap, safe, and well established syn thetic sweetener such as saccharin. Cultivation of the shrub is difficult since t h e seeds are largely sterile, a n d repro duction must be m a d e b y subdivision, a laborious and costly process. While Paraguayan users of t h e leaves have re ported no ill effects, long term, con trolled studies would h a v e to b e made to determine the safety. T h e Bethesda g r o u p n o w hopes to g e t larger quanti ties of stevioside for chronic toxicity a n d other pharmacological tests.
GASES can
be
φ
purified
φ
recovered
φ
separated
φ
deodorized
with A D S O R B I T E activated carbon Tell u s y o u r p r o b l e m , no o b l i g a t i o n .
BRRNEBe-OlEffî CASSAD.Y A t E I G H T H :/ÇpLUMBU S 19, O H ΙΟ In Conodo: BARNEBiY-CHENfY L T D . . St. Johni. Qu«btc
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