Hexane skeleton

Modular Construction of Nine Classes of Spiro[2.3]hexane Scaffolds Using Three Four-Membered-Ring Sulfonium Salts: Synthetic Methodology and Bioisosteric Evaluation

Spiro[2.3]hexane consists of a three-membered ring and a four-membered ring sharing a single spiro atom. The two numbers in “[2.3]” indicate the numbers of atoms in the two rings excluding the shared spiro atom. The entire scaffold therefore contains six ring atoms.