1. Charge-reversal nanoparticles: novel targeted drug delivery carriers
Xinli Chen, Lisha Liu, Chen Jiang Acta Pharm Sin B. 2016 Jul;6(4):261-7. doi: 10.1016/j.apsb.2016.05.011. Epub 2016 Jun 8.
Spurred by significant progress in materials chemistry and drug delivery, charge-reversal nanocarriers are being developed to deliver anticancer formulations in spatial-, temporal- and dosage-controlled approaches. Charge-reversal nanoparticles can release their drug payload in response to specific stimuli that alter the charge on their surface. They can elude clearance from the circulation and be activated by protonation, enzymatic cleavage, or a molecular conformational change. In this review, we discuss the physiological basis for, and recent advances in the design of charge-reversal nanoparticles that are able to control drug biodistribution in response to specific stimuli, endogenous factors (changes in pH, redox gradients, or enzyme concentration) or exogenous factors (light or thermos-stimulation).
2. Expanding the chemical space of 3(5)-functionalized 1,2,4-triazoles
Dmytro M Khomenko, et al. Chem Heterocycl Compd (N Y). 2022;58(2-3):116-128. doi: 10.1007/s10593-022-03064-z. Epub 2022 Mar 23.
An efficient approach to the gram-scale synthesis of 3(5)-substituted, 1,3- and 1,5-disubstituted 1,2,4-triazole-derived building blocks is described. The key synthetic precursors - 1,2,4-triazole-3(5)-carboxylates (20 examples, 35-89% yield) were prepared from readily available acyl hydrazides and ethyl 2-ethoxy-2-iminoacetate hydrochloride. Further transformations were performed following the convergent synthetic strategy and allowed the preparation of 1,3- and 1,5-disubstituted 1,2,4-triazole-derived esters (16 examples, 25-75% yield), 3(5)-substituted, 1,3- and 1,5-disubstituted carboxylate salts (18 examples, 78-93% yield), amides (5 examples, 82-93% yield), nitriles (5 examples, 30-85% yield), hydrazides (6 examples, 84-89% yield), and hydroxamic acids (3 examples, 73-78% yield). Considering wide applications of the 1,2,4-triazole motif in medicinal chemistry, these compounds are valuable building blocks for lead-oriented synthesis; they have also great potential for coordination chemistry. Supplementary information: The online version contains supplementary material available at 10.1007/s10593-022-03064-z.
