sucrose. This strategy paid off with a molecule that is approximately
six hundred times sweeter than sucrose: sucralose, originally mar-
keted under the brand name Splenda, has three of sucrose’s hydroxyl
(-OH) groups replaced by chlorine atoms.
Another synthetic sweetener resulted when a similar strategy of
molecular modification was applied by chemists working for one of
the companies that manufactures aspartame. They chose to start
with aspartame, because it is already two hundred times sweeter than
sucrose, and produce molecular derivatives, hoping to find something
interesting. They did: neotame, a derivative of aspartame formed by
the addition of a six-carbon branched chain onto the aspartic acid,
is fifty times sweeter than aspartame and thus an astounding ten
thousand times sweeter than sucrose! As carfentanil is to morphine,
so neotame is to sucrose. How these vast differences in potency are
generated by the specific molecular changes these substances possess
is not presently understood.
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SucraloseOne more sweeter-than-sucrose example—not a synthetic one, but
one found in a plant: Stevia rebaudiana grows in the Amazon jungle
of South America and is appreciated by the native inhabitants of the
area for the sweet taste of its leaves. (It is a rare leaf that tastes sweet
—many plant leaves taste bitter.) Dehydrated extracts of the leaves are
marketed as a nonnutritive sweetener. Being a plant extract, there are