The antitumor activity of di-n-butyltin(IV) glycylglycinate, and the correlation with the structure of dialkyltin(IV) glycylglycinates in solution

The in vivo activity of Bu2nSnGlyGly, Na(CI2GaGlyGly), and CIGaGlyGly (GlyGly2-- = glycylglycinate) has been investigated in connection with a number of tumors. Positive results have been obtained only for the Bu2nSnIV complex in the case of leukemia P-388 In order to try to interpret the pharmacological data on a molecular basis, the nature of the species present in solutions of AIK2Sn GlyGly complexes, as well as the reactivity of aqueous Me2SnGlyGly, have been studied. The presence of chelated species (I), Figure 1, in organic solvents, and the equilibrium (I) ⇌ (II), Figure 1, in water and mixed water-organic solvent systems, have been inferred from conductance measurements, as well as from studies by Mössbauer (in frozen solution), 1H, 13C, and 119Sn NMR, and ir spectroscopy. Moreover, solvated (II) would release AlK2SnIV moieties, as evidenced by the slow formation of (Me2SnO)n from aqueous Me2Sn GlyGly. The involvement of (I) and (II) in the transportation of these drugs across cell membranes is discussed. © 1985.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

N-valproyl-l-tryptophan for CNS-targeting: synthesis, characterization and efficacy in vitro studies of a new potential antiepileptic drug

A new aminoacidic derivative of valproic acid (VPA) has been synthesized and characterized by analytical and spectral data. The rationale for the preparation of such potential antiepileptic agent is based on the observation that chemical combination of the anticonvulsant pharmacophore, VPA with essential aminoacids could afford more effective and less toxic actives. The synthesis, characterization, physico-chemical parameters functional for crossing Blood Brain Barrier of N-valproyl-L-tryptophan (4) are reported. The Log D pH7.4 (0.3) indicate that (4) is adequate to cross biological membranes. Its chemical and enzymatic stability was assessed. The experiments indicate high stability of compound (4) at pH conditions of physiological fluids. Moreover, both in plasma and in cerebral enzymatic environments compound (4) doesn’t undergo cleavage after 24 h. The anticonvulsant activity of the new compound was assessed against epileptic burst discharges evoked in vitro in rat hippocampal slices (Seizure like events - SLEs) and compared with that of the widely used VPA. Compound (4), even at the lower tested concentration, when compared to VPA, showed an improved protective effect against hippocampal seizures. The collected data suggest that compound (4) could be considered a very valuable candidate for subsequent in vivo evaluation as new potential antiepileptic drug