Heterocyclic Organic Chemistry Heterocycles, Nomenclature, Aromaticity, Five-membered heterocycles: Pyrroles, Indoles, Diazoles, Synthesis, Reactions, Cycloaddition Reactions, Six-membered heterocycles, Pyridine, quinoline, Basicity, Synthesis, Reactions. Heterocyclic compounds versus microbes, Antibiotics, antitumors and as Dyes. Biologically important Heterocycles, Uracils and Purins. Carbohydrates, Definition, Nomenclature, Classification, Monosaccarides: absolute configuration, cyclic structures, oxidation, reduction, osazones, ascorbic acid, amino sugars.