Preface Eric F. V. Scriven and Christopher Antony Ramsden 1. Recent advances in the Synthesis of Benzo[b]furans Majid M. Heravi 2. Recent Advances in the Synthesis of 6-Membered Heterocycles via Domino and Multicomponent Reactions (from 2017-2022) Vahideh Zadsirjan 3. Multi-component synthesis of isatin based bioactive heterocycles Bubun Banerjee 4. Recent advances in the chemistry of pyrazolo[1,5-a]pyrimidines. Jaime Antonio Portilla Salinas Sr. 5. The Literature of Heterocyclic Chemistry, Part XXI, 2021 Galina A. Gazieva 6. Advances in applications of dihydropyridines in organic chemistry Rashad Karimov 7. Strategies for the annulation of five-membered sulfur-nitrogen rings to benzene and heterocycles Oleg A. Rakitin