Synthesis of the Privileged 8‑Arylmenthol Class by Radical Arylation of Isopulegol

Hydrogen atom transfer (HAT) circumvents a disfavored Friedel–Crafts reaction in the derivatization of the inexpensive monoterpene isopulegol. A variety of readily prepared aryl and heteroaryl sulfonates undergo a formal hydroarylation to form 8-arylmenthols, privileged scaffolds for asymmetric synthesis, as typified by 8-phenylmenthol. High stereoselectivity is observed in related systems. This use of HAT significantly extends the chiral pool from the inexpensive monoterpene isopulegol

Modulation of a Photoswitchable Dual-Color Quantum Dot containing a Photochromic FRET Acceptor and an Internal Standard

Photoswitchable semiconductor nanoparticles, quantum dots (QDs), couple the advantages of conventional QDs with the ability to reversibly modulate the QD emission, thereby improving signal detection by rejection of background signals. Using a simple coating methodology with polymers incorporating a diheteroarylethene photochromic FRET acceptor as well as a spectrally distinct organic fluorophore, photoswitchable QDs were prepared that are small, biocompatible, and feature ratiometric dual emission. With programmed irradiation, the fluorescence intensity ratio can be modified by up to ∼100%

Synthesis of the Privileged 8‑Arylmenthol Class by Radical Arylation of Isopulegol

Hydrogen atom transfer (HAT) circumvents a disfavored Friedel–Crafts reaction in the derivatization of the inexpensive monoterpene isopulegol. A variety of readily prepared aryl and heteroaryl sulfonates undergo a formal hydroarylation to form 8-arylmenthols, privileged scaffolds for asymmetric synthesis, as typified by 8-phenylmenthol. High stereoselectivity is observed in related systems. This use of HAT significantly extends the chiral pool from the inexpensive monoterpene isopulegol

Synthesis of the Privileged 8‑Arylmenthol Class by Radical Arylation of Isopulegol

Hydrogen atom transfer (HAT) circumvents a disfavored Friedel–Crafts reaction in the derivatization of the inexpensive monoterpene isopulegol. A variety of readily prepared aryl and heteroaryl sulfonates undergo a formal hydroarylation to form 8-arylmenthols, privileged scaffolds for asymmetric synthesis, as typified by 8-phenylmenthol. High stereoselectivity is observed in related systems. This use of HAT significantly extends the chiral pool from the inexpensive monoterpene isopulegol

Validation of Smart Nanoparticles as Controlled Drug Delivery Systems: Loading and pH-Dependent Release of Pilocarpine

Micelles are good devices for use as controlled drug delivery systems because they exhibit the ability to protect the encapsulated substance from the routes of degradation until they reach the site of action. The present work assesses loading kinetics of a hydrophobic drug, pilocarpine, in polymeric micellar nanoparticles (NPs) and its pH-dependent release in hydrophilic environments. The trigger pH stimulus, pH 5.5, was the value encountered in damaged tissues in solid tumors. The new nanoparticles were prepared from an amphiphilic block copolymer, [(HEMA_19%-DMA_31%)-(FMA_5%-DEA_45%)]. For the present research, three systems were validated, two of them with cross-linked cores and the other without chemical stabilization. A comparison of their loading kinetics and release profiles is discussed, with the support of additional data obtained by scanning electron microscopy and dynamic light scattering. The drug was loaded into the NPs within the first minutes; the load was dependent on the degree of cross-linking. All of the systems experienced a boost in drug release at acidic pH, ranging from 50 to 80% within the first 48 h. NPs with the highest degree (20%) of core cross-linking delivered the highest percentage of drug at fixed times. The studied systems exhibited fine-tuned sustained release features, which may provide a continuous delivery of the drug at specific acidic locations, thereby diminishing side effects and increasing therapeutic rates. Hence, the studied NPs proved to behave as smart controlled drug delivery systems capable of responding to changes in pH