Abstract
Fischer’s approach for structure elucidation of linear aldohexoses is still the most widespread alternative in textbooks for carbohydrates. However, in post-Fischer era, a series of remarkable discoveries and inventions were made in different laboratories, and by their use a more comprehensive and coherent strategy for structure elucidation of linear isomeric aldohexoses can be elaborated. Fischer used the exceptional properties of d-mannose for the knowledge of configuration of C-2 and called it the key of the gate to stereochemistry. We bring the evidence that Fischer had an alternative to this monosaccharide, d-idose. Fischer discovered the correct structure of the enantiomers of tartaric acid by pure intuition but Bijvoet proved it experimentally by means of X-rays. Hybridization, a concept taken by L. Pauling from biology, reconciled physics and chemistry concerning the valence of carbon atom and explained the stereochemical picture that had been empirically elaborated by Van’t Hoff and Le Bel. Other chemical transformations of monosaccharides, useful in the elucidation of their structure, have been also discovered or invented in post-Fischer era.