Synthesis, ex vivo and in vitro hydrolysis study of an indoline derivative designed as an anti-inflammatory with reduced gastric ulceration properties.

The compound 1-(2,6-dichlorophenyl)indolin-2-one (1), planned as a pro-drug of diclofenac (2), was easily synthesized in 94% yield by an intramolecular reaction in the presence of coupling agent (i.e., EDC). Compound 1 showed anti-inflammatory and analgesic activity without gastro-ulcerogenic effects. The chemical and enzymatic hydrolysis profile of the lactam derivative 1 does not indicate conversion to diclofenac (2). This compound is a new non-ulcerogenic prototype for treatment of chronic inflammatory diseases.

Synthesis and total 1H- and 13C-NMR assignment of cephem derivatives for use in ADEPT approaches.

We report the synthesis and total NMR characterization of 5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylic acid-3-[[[(4''-nitrophenoxy)carbonyl]oxy]-methyl]-8-oxo-7-[(2-thienyloxoacetyl)amino]-diphenylmethyl ester-5-dioxide (5), a new cephalosporin derivative. This compound can be used as the carrier of a wide range of drugs containing an amino group. The preparation of the intermediate product, 5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid-3-[methyl 4-(6-methoxyquinolin-8-ylamino)pentylcarbamate]-8-oxo-7-[(2-thienyloxoacetyl)amino]-diphenylmethyl ester-5-dioxide (6), as well as the synthesis of the antimalarial primaquine prodrug 5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid-3-[methyl 4-(6-methoxyquinolin-8-ylamino)pentylcarbamate]-8-oxo-7-[(2-thienyloxoacetyl)amino]- 5-dioxide (7) are also described, together with their total (1)H- and (13)C-NMR assignments.

Prodrugs for the treatment of neglected diseases.

Recently, World Health Organization (WHO) and Medicins San Frontieres (MSF) proposed a classification of diseases as global, neglected and extremely neglected. Global diseases, such as cancer, cardiovascular and mental (CNS) diseases represent the targets of the majority of the R&D efforts of pharmaceutical companies. Neglected diseases affect millions of people in the world yet existing drug therapy is limited and often inappropriate. Furthermore, extremely neglected diseases affect people living under miserable conditions who barely have access to the bare necessities for survival. Most of these diseases are excluded from the goals of the R&D programs in the pharmaceutical industry and therefore fall outside the pharmaceutical market. About 14 million people,mainly in developing countries, die each year from infectious diseases. From 1975 to 1999,1393 new drugs were approved yet only 1% were for the treatment of neglected diseases[3]. These numbers have not changed until now, so in those countries there is an urgent need for the design and synthesis of new drugs and in this area the prodrug approach is a very interesting field. It provides, among other effects, activity improvements and toxicity decreases for current and new drugs, improving market availability. It is worth noting that it is essential in drug design to save time and money, and prodrug approaches can be considered of high interest in this respect. The present review covers 20 years of research on the design of prodrugs for the treatment of neglected and extremely neglected diseases such as Chagas' disease (American trypanosomiasis), sleeping sickness (African trypanosomiasis), malaria, sickle cell disease, tuberculosis, leishmaniasis and schistosomiasis.

Design, synthesis and biological evaluation of new aryl thiosemicarbazone as antichagasic candidates.

The present work reports on the synthesis, biological assaying and docking studies of a series of 12 aryl thiosemicarbazones, which were planned to act over two main enzymes, cruzain and trypanothione reductase. These enzymes are used as targets of trypanocidal activity in Chagas disease control with a minimal mutagenic profile. Three p-nitroaromatic thiosemicarbazones showed high activity against Trypanosoma cruzi in in vitro assays (IC50 < 57 µM), and no mutagenic profile was observed in micronucleous tests. Although the in vitro inhibition test showed that 10-µM doses of eight compounds inhibited cruzain activity, no correlation was found between cruzain inhibition and trypanocidal activity.

A nonstaining and tasteless hydrophobic salt of chlorhexidine.

Chlorhexidine (CHX) remains one of the most effective and widely used antiplaque agents around the world, although its side effects still limit a long-term usage as the patient compliance for oral treatment with CHX. We hypothesize that a less water-soluble tetracation salt of CHX might be able to interact weakly with tooth enamel and oral taste cells, reducing those undesirable side effects of CHX. The chlorhexidine tetrapalmitate (CHXTP) was obtained and the antimicrobial activity was evaluated by hole-plate diffusion method and twofold tube dilution method; for measurement of its propensity to stain, we used the in vitro method of polymethylmethacrylate blocks in an infusion with black tea solution; the rate of its removal from oral cavity was studied by high-performance liquid chromatography measurement of CHX extracted from human saliva samples; and its effect on the human taste perception was evaluated by taste confusion matrix method. The results showed that CHXTP salt is very active against Streptococcus mutans, with no interference on taste perception and a low tendency to stain; however, chlorhexidine digluconate shows a better retention in saliva. The use of polyvinylpyrrolidone turned possible a nonstaining and tasteless CHXTP formulation to linger in mouth.

Wound healing properties and mucilage content of Pereskia aculeata from different substrates

Physiologic growth parameters Wound healing Pereskia aculeata Mill., Cactaceae, is a cactus with high mucilage production, well-known for its nutritional properties. Folk use consists on skin injuries, and mucilage is probably involved in the wound healing activity. This work studied some aspects of its cultivation, specifically regarding soil (substrate), to correlate the effects of nutritional content to mucilage production and to the wound-healing property. Plants were grown under five different soil treatment (sand, crude soil, sand and soil, sand and cattle manure, soil and cattle manure), and after eight months extracts were prepared by turbo-extraction to obtain a crude hydroethanolic extract. We evaluated the effects of these extracts on swelling index, cytotoxicity, and in vitro wound healing property. The results show that the substrate used in cultivation may interfere with mucilage production, but not with cytotoxicity and wound healing, this shows the safety of its use, despite the soil treatment received along the various biomes where P. aculeata is cultivated. Furthermore, morphological studies demonstrated the beneficial effect of the mucilage-containing extract on the fibroblast cell culture, corroborating its folk use for wound healing.