Spiro Heterocycles: Synthesis and Application of Spiro Pyrazol-3-one Derivatives

Abstract

Spiro compounds play an important role in organic chemistry, not only as key structural units in many natural products and pharmaceuticals but also as useful building blocks in synthetic chemistry. This review deals with the synthesis and application of spiro heterocycles, especially spiro pyrazol-3-ones (SPOs). SPOs represent a common scaffold present in a wide range of biological active compounds, such as antibacterial, analgesic, phosphodiesterase, inotropic, acetyl-CoA carboxylase, PPARa, RaIA, and antitumor activities, among others. The structural features of SPOs provide them with increased reactivity, and SPOs undergo a series of interesting reactions under appropriate conditions, giving efficient methods for the construction of many useful organic compounds. The exploration of SPOs novel reaction has attracted much attention of organic chemists. Generally, SPOs reaction types include nucleophilic addition, ring-opening, and ring transformation reactions. The present review summarizes the advances on SPOs during the period of 2008 to 2021 in our laboratory. CONTENTS 1. Introduction 2. Synthesis and Application of SPOs Containing Cyclopropane Moiety 3. Synthesis and Application of SPOs Containing Oxirane Moiety 4. Synthesis and Application of SPOs Containing Isoxazoline Moiety 5. Synthesis of SPOs Containing Iminolactone and/or Cyclic Imide Moiety 6. Synthesis of SPOs Containing Quinazoline Moiety 7. Synthesis and Application of SPOs Containing Cyclobutathiazole Moiety 8. Conclusion