Medicinal Chemistry - Volume 8, Issue 5, 2012

The reaction of K2PtCl4 with anticancer-alkylating agent mechlorethamine hydrochloride (CH3NH(C2H4Cl)2 x HCl = HN2xHCl), in the molar ratio 1 : 2, affords the complex [H2N2]2[PtCl4]. In vitro antimicrobial and lipoxygenase inhibitory activities of the complex and its precursor were evaluated. Antimicrobial activity of the HN2xHCl and [H2N2]2[PtCl4] complex was investigated against 29 species of microorganisms. Testing is performed by microdilution method. Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) have been determined. The difference between antimicrobial activity of precursor and corresponding platinum(II) complex is noticed and the activity of the precursor was higher. Tested compounds demonstrated the high and significant antifungal activity and low to moderate antibacterial activity. It was shown that the gram-positive bacteria were more sensitive than the gramnegative. UV absorbance-based enzyme assays were performed with HN2xHCl and [H2N2]2[PtCl4] complex, in order to evaluate their in vitro inhibitory activity of soybean lipoxygenase (LOX), also. Assay with LOX showed significantly greater inhibitory activity of the complex, than the precursor.

A series of compounds including N-aryl substituents of phthalimide and 4-nitrophthalimide were synthesized and evaluated for their anticonvulsant properties. The in vivo screening data suggest that all the analogs have the ability to protect against pentylenetetrazole-induced seizures. These compounds exerted their maximal effects 30 min after administration. The most potent compound in both, tonic and clonic seizure was 1-naphthyl derivative (comp. 6), which was more active than the reference drug known as Phenytoin. Using an open pore model of the Na channel, these anticonvulsants were docked in the active site and examined in relation to the residues identified by mutagenesis as important for their binding energies. Docking studies revealed that all compounds (1-13) interacted mainly with residues II-S6 of NaV1.2 by making hydrogen bonds and additional hydrophobic interactions with domain I and II in the channel's inner pore.

Tolbutamide (N-[(butylamino)carbonyl]-4-methylbenzenesulfonamide, CAS 64-77-7, I) is the first generation of potassium channel blocker and sulfonylurea oral hypoglycemic drug that imparts marked blood glucose lowering effect in type 2 diabetes or non-insulin dependent diabetes mellitus (NIDDM) patients. In this study, I and its two new analogs with substituting butylamine side by 3-diethylamino-1-propylamine (3) and 3-triethoxysilyl-1-propylamine (4) were synthesized and their antidiabetic and hypolipidemic activities were evaluated applying known procedures, and compared with both I and glibenclamide (II, well known second-generation sulfonylurea antidiabetic drug). The results showed that these new drugs (III and IV) were more potent than I and II and it could be concluded that changing the amine side of I would produce more potentials in new drugs (III and IV) of the first generation, to be named as the third generation. Also investigations on hypoglycemic and lipid lowering effects of these drugs proved that IV could reduce glucose, triglyceride (TG) and a low density lipoprotein (VLDL) level in blood serum more than others (I-III), 16 days after STZ injection.

We have studied inhibition of Plasmodium falciparum lactate dehydrogenase (pfLDH) by dihydroxynaphthoic acid (DHNA) analogues derivatives of hemigossypol-sesquiterpene found in cottonseed known to exhibit antimalarial activity. Molecular models of pfLDH-DHNA complexes were prepared from high-resolution crystal structures containing DHNA and azole inhibitors and binding affinities of the inhibitors were computed by molecular mechanics – polarizable continuum model of solvation (MM-PCM) approach. The 3D structures of the pfLDH-DHNA complexes were validated by a QSAR model, which confirmed consistency between the computed binding affinities and experimental inhibition constants for a training set and validation set of twelve DHNA inhibitors obtained from literature. Novel more potent DHNA analogs were identified by structure-based molecular design and predicted to inhibit pfLDH in the low nanomolar concentration range. In addition, the designed DHNA analogs displayed favorable predicted ADME-related profiles and an elevated selectivity for the pfLDH over the human isoform.

A simple and practical synthetic approach for tasigna was described here in six steps with high yield (40%). All of the intermediates and final target compound were isolated cleanly in high yield without a need for chromatographic purification. Significantly, the facile synthetic route proposed in this work has the characteristics of mild synthetic conditions, inexpensive reagents, high yield and simple operation.