The search for a wide spectrum of antimicrobial agents that can avoid resistance while maintaining reasonable side effects has led to ozonated oils experiencing an increase in scientific interest and clinical applications. The treatment of vegetable oils with ozone leads to the creation of a reservoir of ozone that slowly releases into the skin thanks to the fact that ozone can be held as ozonides of unsaturated fatty acids. Interest in the use of ozonated oils has meant that several ozonated-vegetable-oil-containing products have been commercialized as cosmetic and pharmaceutical agents, and in innovative textile products with antibacterial activity. New approaches to the delivery of ozonated oils have very recently appeared in an attempt to improve their characteristics and reduce drawbacks, such as an unpleasant odor, high viscosity and undesired effects on skin, including irritation and rashes. The present review focuses on the current status of delivery agents that use ozonated oils as antimicrobial agents in topical (dermal, skin, and soft tissues) treatments. Challenges and future opportunities for these delivery systems will also be discussed.

This protocol is for the ultrasound (US)-assisted 1,3-dipolar cycloaddition reaction of azides and alkynes using metallic copper (Cu) as the catalyst. The azido group is a willing participant in this kind of organic reaction and its coupling with alkynes is substantially improved in the presence of Cu(I). This protocol does not require additional ligands and proceeds with excellent yields. The Cu-catalyzed azide-alkyne cycloaddition (CuAAC) is generally recognized as the most striking example of 'click chemistry'. Reactions involving metals represent the favorite domain of sonochemistry because US favors mechanical depassivation and enhances both mass transfer and electron transfer from the metal to the organic acceptor. The reaction rate increases still further when simultaneous US and microwave irradiation are applied. The US-assisted click synthesis has been applied for the preparation of a wide range of 1,4-disubstituted 1,2,3-triazole derivatives starting both from small molecules and oligomers such as cyclodextrins (CDs). Using this efficient and greener protocol, all the adducts can be synthesized in 2-4 h (including work-up and excluding characterization). Click chemistry has been shown to be able to directly link chemistry to biology, thus becoming a true interdisciplinary reaction with extremely wide applicability.

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Glycerol has the potential to be both an excellent renewable solvent in modern chemical processes and a versatile building block in biorefineries. Both of these potential applications may be made easier and more convenient by microwave and/or ultrasound ir radiation. As glycerol is a nontoxic, biodegradable compound, it will provide important environmental benefits to new platform products. Furthermore, significant markets in polymers, polyethers, fuel additives, nanoparticles and other valuable compounds may well be opened up by cutting down the high purification cost of glycerol. The aim of this review is to highlight the best literature examples of glycerol being used, either as solvent or as a reagent, to give interesting results under microwave or ultrasound irradiation.

The ultrasound-assisted cross-linking of chitosan with hexamethylene diisocyanate with the simultaneous incorporation of Pd(OAc)2 resulted in a catalyst which is suitable for the solid-state Suzuki cross-coupling of poorly reactive (hetero)aryl chlorides with phenylboronic acid. Reactions were carried out solvent-free in planetary ball mill allowing the catalyst to be recycled several times.

Chitosan (CTS), a biocompatible, biodegradable, non-toxic polymer, dissolves in water only if pH is lowered under 6.5, when a substantial fraction of the amino groups is protonated. Its range of application has been much extended by partially depolymerising it or converting it to water-soluble derivatives. Working under high-intensity ultrasound at 17.8-18.5 kHz, using either a simple horn or a cup horn, we achieved a controlled depolymerization of CTS, also prepared in high yields several derivatives that can be useful intermediates for further chemical modification, as well as several water-soluble derivatives that lend themselves to a host of industrial applications. Compared to conventional methods, all these reactions went to completion in considerably shorter times at lower temperatures.

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