Alpha-methylene-gamma-lactone fused to steroidal ring D as potential antitumor agent

Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.

Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...

Malonic ester synthesis is a method to obtain α substituted carboxylic acids from ꞵ-diesters such as diethyl malonate and alkyl halides.

Amphotericin B is a broad-spectrum antifungal agent that exploits structural differences between fungal and mammalian cell membranes. Its amphipathic structure—featuring a hydrophobic polyene-lactone ring and a hydrophilic region containing mycosamine and carboxylic acid groups—enables selective binding to ergosterol, a sterol predominantly found in fungal plasma membranes. This selective interaction underlies the drug’s antifungal activity, although weak binding to cholesterol contributes to...