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A highly efficient multigram synthesis of spirocyclic and fused isoxazoline building blocks is described. Isoxazoline‐3‐carboxylates were synthesized via a regioselective 1,3‐dipolar cycloaddition reaction of 2‐chloro‐2‐(hydroxyimino)acetate and carbo‐ or heterocyclic alkenes bearing endo‐ or exocyclic C=C double bonds, resulting in fused or spirocyclic isoxazolines, respectively. The preparation of up to 300 g of these compounds was achieved in a single run. The ester group of isoxazolines was then subjected to common synthetic transformations for the synthesis of corresponding building blocks, including alcohols, chlorides, azides, amines, aldehydes, carboxylic acids, amino acids and their derivatives, difluoromethyl‐substituted compounds, and bicyclic γ‐lactones. Additionally, a direct cycloaddition‐based approach to the synthesis of aminoalkyl‐ and chloromethyl‐substituted isoxazolines was proposed to improve their preparation. The described isoxazoline building blocks are expected to be valuable tools for drug discovery. [ABSTRACT FROM AUTHOR]

A review with 636 references. The literature on saturated amino sulfonic acids with primary/secondary amino group and their derivatives from XIX century to 2016 is surveyed, focusing mainly on results published in the last two decades. Synthesis of saturated amino sulfonic acids and their derivatives, their occurrence among natural products, as well as their use for design of peptidomimetics, conjugates with various molecules of practical significance, applications as building blocks for drug discovery and for other reasons are discussed. [ABSTRACT FROM AUTHOR]