The discovery of glucose, among other findings, we owe to Joseph Louis Proust, a French chemist who developed most of his work in Spain.
He is also known for developing Proust's Law or Law of Defined Proportions; This law comes to say that when two or more elements are combined to give rise to a compound, they always do so in the same proportion, regardless of their physical state and the way in which it is obtained.
He is considered the founder of modern chemistry.