Chemical modifications of bile acids under high-intensity ultrasound or microwave irradiation.

High-intensity ultrasound (HIU) and microwave (MW) irradiation, having emerged as effective promoters of organic reactions, were exploited for the synthesis of bile acids derivatives. Esterification, amidation, hydrolysis, oxidation, and reduction were investigated. Compared to conventional methods, both techniques proved much more efficient, increasing product yields and dramatically cutting down reaction times. Scaled-up studies are now under way.