The association constants Kb of three receptors (I-III), designed to have both enhanced hydrogen bonding donor strength and conformational preorganization, with biotin analogues (1-5) are reported. 1H-NMR titrations using the saturation conditions have been employed to determine the association constants Kb.

In this study, a series of five ring-substituted 2-styrylquinazolin-4(3H)-one and five ring-substituted 4-chloro-2-styrylquinazoline derivatives were prepared. The procedures for synthesis of the compounds are presented. The compounds were analyzed using RP-HPLC to determine lipophilicity. They were tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. Primary in vitro screening of the synthesized compounds was also performed against four mycobacterial strains. Several compounds showed biological activity comparable with or higher than the standard isoniazid. For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds are discussed, as well as their structure-activity relationships (SAR).

Experimental–theoretical works explain the energetics of the packing of a virus with deoxyribonucleic acid (DNA) and the injection of the DNA into a cell. Washing has a limited effect on enteric viruses in food. Alternatives are needed to acidic matrixes. Feline calicivirus is not a good control model. Various protocols are being prepared. New challenges are: new methods, impact of new technologies, significance of detection, new virus models and emergent–re-emergent viruses. The forthcoming step is to re-develop the virus to direct it and contain the most common contaminants in food: salmonella, listeria, staphylococcus and Mycobacterium tuberculosis.

The synthesis and the physicochemical characterization of a new contrast agent for magnetic resonance imaging (MRI), Gd-C4-thyroxin-DTPA, which has a high affinity for human serum albumin (HSA), are reported. The results show that this chelate is characterized by a relatively high relaxivity, which increases moreover with the concentration. This reflects an aggregation of the molecules in solution. It is also characterized by a better stability versus the transmetallation with the zinc ion than the parent compound, the Gd-DTPA (Magnevist®, Bayer Healthcare). The study of its interaction with human serum albumin was performed by the proton relaxometry technique, which has revealed a relatively high affinity (Ka of the order of 10000 M-1, with 2 binding sites). Finally, competition experiments with ibuprofen and salicylate, of which the binding sites on HSA are known, were performed by the NMR diffusometry method. The results suggest that the chelate shares one of the binding site of ibuprofen.

This study describes a promising one-pot synthesis of [2-(5-benzyl-4-phenyl-4H- [1,2,4]triazol-3-thio)-acetyl]-amino acid methyl esters 6a-h and dipeptides 10a-e were successfully synthesized starting from amino acid esters 5a-h, 9a-e and azides 4, 8a,b respectively. On the other hand, azide 4 underwent Curtius rearrangement to the corresponding isocyanate which subsequently reacted with selected aliphatic and/or aniline derivatives to give the corresponding urea derivatives 11 and 12a, b. Also reaction of isocyanate with secondary amines gave amide derivatives 13a, b.

A library of 19 novel 4-(4-phenylpiperazine-1-yl)benzamidines has been synthesized and evaluated in vitro against Pneumocystis carinii. Among these compounds, N-ethyl and Nhexyl 4-(4-phenylpiperazine-1-yl)benzamidines emerged as the most promising compounds with inhibition percentages at 0.1μg/ml of 61(percent) and 56(percent) respectively.

The synthesis of a new disazo dyes containing 4,4'-diaminostilbene-2,2'-disulfonic acid as middle component is presented. The synthesized dye was analyzed by thin layer chromatography (TLC), electronic spectra (VIS) and HPLC technique. The structure was elucidated by FT/IR and 13CNMR spectroscopy. The colouristic evaluation of the synthesized dye indicates that this dye could be ranged as a direct dye, suitable for application on cellulosic substrates. Further, an in vivo imagistic skin study was performed in order to evaluate the individual human skin tolerance for this new disazo dye.

Skin penetration enhancers are used to allow formulation of transdermal delivery systems for drugs that are otherwise insufficiently skin-permeable. The series of seven esters of 6-(2,5-dioxopyrrolidin-1-yl)-2-(morpholin-4-yl)hexanoic acid as potential transdermal penetration enhancers was formed by multistep synthesis. The general synthetic approach of all newly synthesized compounds is presented. Structure confirmation of all generated compounds was accomplished by IR, 1H, 13C NMR and HR-MS spectroscopy. All the prepared compounds were analyzed using RP-HPLC method for the lipophilicity measurement and their lipophilicity (log k) was determined.

A concise approach towards trisubstituted optically active azetidines, including a study of the scope and limitations of the synthetic sequence, is reported. The synthesis comprises the L-proline organocatalyzed three component reaction between substituted benzaldehydes, anilines and an enolizable aldehyde, followed by the in situ reduction of the resulting β-aminoaldehydes to the corresponding β-aminoalcohols and final intramolecular cyclization of the latter by way of the intermediate tosylates.

A series of halogen containing 1,4-naphthoquinon derivatives (1-4,5a-f) were synthesized and studied for their antifungal activities against C. albicans ATCC10231, C. albicans 955, T. mentagrophytes and M. gypseum. The results indicate that compound 2-hydroxy-3-chloro-1,4-naphthoquinone (2), 2-(N-acetyl)- acetamido-3-chloro- 1,4-napthoquinone (3) and 2-(N-acetyl)-acetamido-3-chloro- 1,4- napthoquinone (4) have potent antifungal activity. Among these promising antifungal candidates, 2 and 4 showed better activity than that of clinically antifungal drug clotrimazole (MIC = 8 μg/ml) with MIC = 1 μg/ml and 4 μg/ml, respectively against C.albicans ATCC10231. Compound 2 also exhibited an extremely potent activity (MIC = 0.25 μg/ml) against C.albicans 955 strain compared with clotrimazole (MIC = 16 μg/ml). Structure and activity relationship (SAR) study demonstrated that replacing of 3-position in 1,4- naphthoquinon by a Cl group is essential for antifungal activity. Meanwhile, antifungal activity was decreased considerably when the hydrogen atom at position-2 in naphthoquinone structure were replaced by a bulky group (e.g. diacetyl of phenyl group).