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In view of the anticancer effect of nitrosoureas a set of four new N-(2-chloroethyl)-N-nitrosourea (CENU) derivatives was synthesized. An in silico absorption, distribution, metabolism, excretion and toxicity (ADME/Tox) prediction study revealed that the CENU derivatives satisfied all the required criteria for oral administration and introduced them as remarkable anticancer candidates in the central nervous system (CNS). A comparative solvatochromic study including the Kamlet-Taft, Catalán and Laurence models indicated that the solvatochromic behavior of the CENUs depended on both, unspecific and specific solvent-solute interactions. In detail, the solvatochromic effect of the solvent polarity on the absorption and emission maxima was significant for all CENUs, whereas the solvatochromic effect of the solvent's ability to donate or accept hydrogen bonds on the absorption and emission maxima was critically dependent on the electron density of the N'-aryl group. From the solvatochromic comparison method, excellent correlations (r ≥ 0.890) were obtained between the ADME parameters and the solvatochromic regression coefficients obtained by the Catalán model. As potential stabilizers, inclusion complexes of the investigated CENU derivatives with β-cyclodextrin (β-CD) were also explored. The spectrofluorimetric host-guest experiments included double-reciprocal Benesi-Hildebrand plots as well as the molar ratio and continuous variation plots (Job's plots), which established a 1:1 β-CD to CENU binding stoichiometry and relatively high affinities of β-CD for CENU derivatives., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The effects of solvent dipolarity/polarizability and solvent-solute hydrogen bonding on the photophysical properties of the antineoplastic drug lomustine were analysed by means of the linear solvation energy relationship (LSER) concept proposed by Kamlet and Taft. The LSER method enabled the overall solvent effects to be quantitatively estimated and separated into specific and non-specific contributions. The molecular encapsulation of lomustine by β-cyclodextrin (β-CD) has been studied using fluorescence spectroscopy. The results are discussed in terms of the binding parameter and the effect of the solvent used. It was concluded that β-CD forms a 1:1 inclusional complex with lomustine in acetonitrile solution and its association constant was calculated to be 500 M(-1). In addition, and for the first time, a simple, rapid and high sensitive fluorimetric method for the determination of lomustine was developed based upon the enhancement effect produced through complex formation with β-CD. The new approach for the quantification of lomustine in the presence of β-CD was described in aqueous and organic solutions. Better limits of detection (0.31 µg ml(-1)) and quantification (1.05 µg ml(-1)) were obtained in aqueous solution with respect to those obtained in organic solvent., (Copyright © 2015 John Wiley & Sons, Ltd.)

A study of inclusion complexes of six N-sulfamoyloxazolidinone derivatives with beta-cyclodextrin is described. The inclusion complexes were prepared in solution and in solid state with stoichiometry host-guest 1:1, and characterized. In solution, the complexation was carried out by spectrophotometric measurements at 25 degrees C. The stoichiometries and stability constants of complexes at various pHs have been determined using second-derivative spectrophotometry UV-vis. Hydrophobic properties of N-sulfamoyloxazolidinones are improved following their inclusion into beta-CD.

Host-guest association between four CENS (derivated from piperidine, dibenzylamine, dicyclohexylamine and methyl prolinate) and beta-cyclodextrin was carried out in solution and solid state. Characterisation, stoichiometry, solubility, dissociation constants and stability of such complexes were studied, showing that the inclusion with beta-CD appears as a promising mode of formulation of 2-chloroethylnitrososulfamides.