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Molecular charge-transfer complexes of three N-aryl-N'-isopropyloxycarbonylsulfamides derivatives with π-acceptors tetracyanoethylene (TCNE), and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), were studied by using zero and second order derivative UV spectrophotometry in different solvents at four different temperatures within the range of 20-35 °C. The stoichiometries of the complexes were found to be 1:1 ratio between donors and acceptors using Job's method. The data were analyzed in terms of their stability constant (K), molar extinction coefficient (εCT), thermodynamic standard reaction quantities (ΔG°, ΔH°, ΔS°), oscillator strength (f), transition dipole moment (μEN) and ionization potential (ID). The results show that the stability constant (K) for the complexes was found to be dependant upon the nature of electron acceptor, electron donor, and polarity of used solvents., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Three series of derived compounds of N, Aryl-N',Sulfamoyloxazolidin-2-ones were synthesized starting from chloro-sulfonylisocyanate (CSI) by carbomoylation, sulfamoylation and intramolecular cyclization reactions followed by methylation and heterocyclic reopening reactions. This later is based on a new hydrolysis method which uses a solid support, in order to obtain the correspondent amino-alcohols, which allowed isolating a new amino-alcohol ester. Measurements of the hydro-solubility by determination partition coefficient (log p) in water/octanol system were carried out by spectrophotometry. The antibacterial activities in vitro of some synthesized compounds were evaluated on a "Staphylococus aureus" strain in a Mûller-Hintone medium, showing good activity for some of them. All the synthesized compounds are characterized by IR, (1)H NMR and mass spectroscopy (ESI-MS).

The kinetics decomposition of 2-chloroethylnitrososulfamides (CENS) was studied in aqueous buffered solutions with pH ranging from 0 to 14. The study was monitored by RP-LC-MS and conventional UV spectrophotometry. The reaction proceeded via a pseudo-first-order kinetic with significant correlation coefficient. The major decomposition products from CENS after incubation in phosphate buffer were isolated and identified by NMR and mass spectrometry. The results indicate that the mechanism pathway involves a denitrosation of the CENS and competitive hydrolysis with nucleophilic attack on the sulfur atom and formation of sulfamate compounds.