Toxicological investigation and antinociceptive property of potassium thiophene-3-trifluoroborate

RMD86, a thiophene derivative, promotes antinociceptive and antipyretic activities in mice

Treatment of pain and fever remains an important challenge for modern medicine. Non-steroidal anti-inflammatory drugs (NSAIDs) are the pharmacological options most often used, but their frequent use exposes the patient to serious side effects and dangerous drug interactions. In this context, thiophene derivatives are promising therapeutic alternatives. In this study, we evaluated the in vivo and in silico antinociceptive and antipyretic properties of RMD86, a thiophene derivative. At 100 mg/kg, RMD86 induced no significant changes in the motor coordination of mice in the Rotarod test. At 25, 50, and 100 mg/kg RMD86 significantly reduced the number of abdominal contortions induced by acetic acid (antinociceptive activity) in mice when compared to the control. In the formalin test, for the first phase, there was a reduction in licking times at doses of 50 and 100 mg/kg. In the second phase, reduction occurred at all doses. In the hot plate test, RMD86 (at 100 mg/kg) increased latency time in the first 30 min. For antipyretic activity, RMD86, when compared to the reference drug acetaminophen (250 mg/kg), significantly reduced pyrexia at 30, 60, and 120 min, at dosages of 25, 50 and 100 mg/kg. Molecular docking studies revealed that RMD86 presents a greater number of interactions and lower energy values than both the co-crystallized ligand and the reference drug (meloxicam) against COX-1 and COX-2 isoenzymes. The results give evidence of the analgesic and antipyretic properties like NSAIDs suggesting its potential for pain therapy.

Physicochemical characterisation of novel tetrabutylammonium aryltrifluoroborate ionic liquids

While there have been many studies on the physicochemical characterisation of ILs, little work has previously been reported on the properties unique to the trifluoroborate anion. Here we have characterised the thermal properties, viscosity, liquid nanostructure and intramolecular interactions of 15 novel aryltrifluoroborate ILs. These ILs all contained a tetrabutylammonium cation paired with either meta- or para-substituted aryltrifluoroborate anions, or di-anionic substituted aryltrifluroborate anions. It was found that of the 15 samples analysed, 4 would technically be considered molten salts as they have melting points greater than 100 °C. Overall the structure-property relationship trends of these samples are similar to those previously reported for alkyl and perfluoroalkyltrifluoroborate ILs which contained K+ or Cs+ cations, with the big difference being the ILs in this study having considerably lower melting points.

Further analysis of acute antinociceptive and anti-inflammatory actions of 4-phenylselenyl-7-chloroquinoline in mice

A new quinoline containing selenium, 4-phenylselenyl-7-chloroquinoline (4-PSQ), was described and synthetized by our research group. Recently, we demonstrated the potential antinociceptive and anti-inflammatory of 4-PSQ. For this reason, the first objective of this study was to expand our previous findings by investigating the contribution of glutamatergic, serotonergic, and nitrergic systems to the acute antinociceptive action of this compound. Pretreatment with 4-PSQ (0.01-25 mg/kg, p.o.) reduced the nociception induced by glutamate. MK-801 (an uncompetitive antagonist of the N-Methyl-d-aspartate (NMDA) receptor) blocked the antinociceptive effect exerted by 4-PSQ (25 mg/kg, p.o.) in the acetic acid-induced abdominal writhing test. The pretreatment with WAY100635 (a selective antagonist of 5-HT_1A receptor), ketanserin (a selective antagonist of 5-HT_2A/2C receptor), and pindolol (a nonselective antagonist of 5-HT_1A/1B receptors) partially blocked the antinociceptive effect caused by 4-PSQ (25 mg/kg, per oral, p.o.) in the acetic acid-induced abdominal writhing test. Nitric oxide precursor, l-arginine hydrochloride, partially reversed antinociception caused by 4-PSQ or ω-nitro-l-arginine (l-NOARG). Treatments did not modify the locomotor and exploratory activities of mice. Additionally, the acute anti-inflammatory effect of 4-PSQ in a model of pleurisy induced by carrageenan in mice was investigated. 4-PSQ reduced the cellular migration, pleural exudate accumulation, and myeloperoxidase activity induced by carrageenan exposure. 4-PSQ protected against the increase in reactive species levels and reduction of nonprotein thiol levels induced by carrageenan. Data presented here showed that the modulation of serotonergic, nitrergic, and glutamatergic systems contributed to the antinociceptive effect of 4-PSQ and it reinforced the therapeutic potential of this quinolinic compound for acute inflammation.

Boron chemicals in diagnosis and therapeutics

Advances in the field of boron chemistry have expanded the application of boron from material use to medicine. Boron-based drugs represent a new class of molecules that possess several biomedical applications including use as imaging agents for both optical and nuclear imaging as well as therapeutic agents with anticancer, antiviral, antibacterial, antifungal and other disease-specific activities. For example, bortezomib (Velcade(®)), the only drug in clinical use with boron as an active element, was approved in 2003 as a proteasome inhibitor for the treatment of multiple myeloma and non-Hodgkin's lymphoma. Several other boron-based compounds are in various phases of clinical trials, which illustrates the promise of this approach for medicinal chemists working in the area of boron chemistry. It is expected that in the near future, several boron-containing drugs should become available in the market with better efficacy and potency than existing drugs. This article discusses the current status of the development of boron-based compounds as diagnostic and therapeutic agents in humans.

Allylation of functionalized aldehydes by potassium allyltrifluoroborate catalyzed by 18-crown-6 in aqueous media

An efficient method for the allylation of aldehydes containing a broad range of functional groups using potassium allyltrifluoroborate is described. The reaction utilizes a catalytic amount of 18-C-6 in biphasic media under open atmosphere and room temperature to provide the corresponding homoallylic alcohols in high yields and without the necessity of any subsequent purification.

(1)H, (13)C, (19)F and (11)B NMR spectral reference data of some potassium organotrifluoroborates

Complete (1)H, (13)C, (19)F and (11)B NMR spectral data for 28 potassium organotrifluoroborates are described. The resonance for the carbon bearing the boron atom is described for most of the studied compounds. A modified (11)B NMR pulse sequence was used and better resolution was observed allowing the observation of (11)B-(19)F coupling constants for some of the studied compounds.