This paper describes synthetic studies towards carolacton, a highly potent antibiotic against dental caries and endocarditis related bacterium Streptococcus mutans. The synthesis of the 12-membered lactone with a diversely functionalized keto acid side chain was accomplished by utilizing a blend of chiral pool and aldol strategies. Carbon chain C1-C8 was derived by utilizing Paterson aldol methodology and a Corey-Fuchs reaction. The C9-C19 chain was prepared by means of iterative Evans asymmetric alkylations and an E-selective cross-metathesis reaction.

An eco-friendly simple and efficient synthesis of 3,3'-bis(indolyl)methanes was carried out by electrophilic substitution reaction of indole with structurally divergent aldehydes by using succinic acid as green catalyst and water as green solvent under microwave irradiation. The advantages of this protocol are excellent yields, higher availability, inexpensive catalyst, lack of toxicity, shorter reaction time and more environmentally friendly catalyst. The reaction is chemoselective applicable only to aldehydes.

A highly convergent stereoselective total synthesis of achaetolide, a ten-membered lactone is described. The ring-closing metathesis reaction was used to construct the macrocycle and E-olefinic moiety in the molecule. The key acid and alcohol fragments were synthesized from a single chiral pool material D-mannitol.