Isosaccharino- and Glucosaccharino-Lactones as Chirons for the Syntheses of Natural Compounds and Analogs of Biological Relevance

α-D-lsosaccharino- and α-glucosaccharino-1,4-lactones, readily obtained by alkaline treatment of abundant sugars, represent versatile chiral non-racemic starting materials for the syntheses of molecules containing a tertiary alcohol function. Their usefulness is undoubtedly illustrated by the numerous regio- and stereocontrolled syntheses of biologically relevant molecules such as antibiotics, anticancer agents, pheromones and nucleosides. 1. Introduction 1.1. Access from natural sugars 1.2. Mechanism of Formation and Synthesis 2. α-D-Isosaccharino- 1,4-lactone as starting material for 2.1. Subunits of antibiotics or antibiotic synthesis 2.2. Frontalin pheromone synthesis 2.3. Ring A of the anthracyclinone incorporation 2.4.C-branched-chain nucleoside analogs 2.5. Miscellaneous 3. α-D-Glucosaccharino- 1,4-lactone as starting material for: 3.1. Synthesis of antibiotic subunits 3.2. Total synthesis of AK-toxin II 3.3. Incorporation of anthracyclinones in ring A 3.4. C-branched-chain nucleoside analogs