The Red Bull effect
Caffeine and glucose (also called grape sugar) has each a well-known effect.
Caffeine acts particularly in the brain by blocking the receptor(s) for the inhibitory neurotransmitter adenosine.
The adenosine level increases by physical efforts and by the time we are awake.
The caffeine molecule resembles the adenosine molecule.
Maybe the effect of caffeine and glucose can be enhanced by creation of a stuff that resembles adenosine even more
than caffeine alone does, in a reaction between caffeine and glucose.
It should make up a stuff with an effect stronger than obtainable by the usual table sugar (the disaccharide sucrose) + coffee/caffeine.
The Red Bull drink contains both caffeine and glucose, and the reason why this drink works so well could be a chemical reaction between glucose and caffeine.
Chemically it is fully feasible that there will be created a compound which resembles adenosine more than caffeine alone does.
Thus there will be a stronger effect, ie a better blockage of the receptor(s).
See picture attachment – it shows the common formation of a glycosidic bond,
where nitrogen attaches to the anomeric carbon in a nucleophilic substitution reaction. Acidic pH will catalyze this reaction.
I have not tried to blend coffee and glucose. I don`t know the health risks, not even for the legal Red Bull drink.
Please be responsible.