Design, synthesis, antibacterial activity and toxicity of novel quaternary ammonium compounds based on pyridoxine and fatty acids

A diverse series of 43 novel "soft antimicrobials" based on quaternary ammonium pyridoxine derivatives which include six-membered acetals and ketals of pyridoxine bound via cleavable linker moieties (amide, ester) with a fragment of fatty carboxylic acid was designed. Nine compounds exhibited in vitro promising antibacterial activity against Gram-positive and Gram-negative bacterial strains with MIC values comparable with reference antiseptics miramistin, benzalkonium chloride and chlorohexidine. On various clinical isolates, the lead compounds 6i and 12a exhibited antibacterial activity comparable with that of benzalkonium chloride while higher than that of miramistin. Moreover, 6i and 12a were able to kill bacteria embedded into the matrix of mono- and dual species biofilms. The treatment of bacterial cells by either 6i and 12a lead to fast depolarization of the membrane suggesting that the membrane is an apparent molecular target of compounds. 6i and 12a were non mutagenic neither in SOS-chromotest nor in Ames test and non-toxic in vivo at acute oral (LD₅₀ > 2000 mg/kg) and cutaneous administration (LD₅₀ > 2500 mg/kg) on mice. Taken together, our data allow suggesting described active compounds as promising starting point for the new antibacterial agents development.

Drug Discovery for Soft Drugs on TRPV1 and TRPM8 Channels Using the Passerini Reaction

Multicomponent transformations, such as Ugi and Passerini reactions, allow for the fast synthesis of libraries of medium complexity, avoiding the formation of waste residues and significantly reducing time and money expenditure. Although the Ugi reaction has found a vast number of uses in medicinal chemistry, the employment of the Passerini reaction has received scant attention due to the formation of an α-acyloxyamide, which hardly resists the hydrolytic enzymes in the body. On the other hand, an overlooked possibility with the Passerini products is to exploit the presence of an ester group in the design and synthesis of soft drugs. We started to fill this gap, designing and synthesizing a series of TRPV1 and TRPM8 agonists able to act as soft drugs by using the Passerini reaction.

Energy drinks and escalation in drug use severity: An emergent hazard to adolescent health

The aim of the current study is to determine whether energy drink consumption contributes to drug use and, more specifically, an escalation in the severity of drug use. We first examine the association between energy drink use and hard drug use, and subsequently investigate whether soft drug use mediates this relationship. Potential moderating influences are also investigated by testing whether the degree of mediation varies by age, gender, and race. The current study uses a nationally representative sample of 8th (ages 13-14), 10th (ages 15-16), and 12th (ages 17-18) grade adolescents from the 2015 Monitoring the Future survey. Negative binomial regression is employed to examine associations between energy drink consumption and soft and hard drug use. Mediation results indicate that energy drink consumption is significantly associated with increased soft drug use, which is, in turn, associated with significant increases in hard drug use. This cascading effect of energy drink consumption on drug use appears to be stronger among younger females and older males. Results for the moderating effect of race are mixed. Energy drinks appear to pose an important threat to adolescent health in the form of soft and hard drug use. The United States may want to consider adopting energy drink policies similar to European countries and Canada, which require warning labels on beverages with high caffeine content.

Chemical delivery systems and soft drugs: Retrometabolic approaches of drug design

Inclusion of metabolic considerations in the drug design process leads to significant development in the field of chemical drug targeting and the design of safer drugs during past few years which is a part of an approach now designated as Retro metabolic drug design (RMDD). This approach represents systematic methodologies that integrate structure-activity and structure-metabolism relationships and are aimed to design safe, locally active compounds with an improved therapeutic index. It embraces two distinct methods, chemical delivery systems and a soft drug approach. Present review recapitulates an impression of RMDD giving reflections on the chemical delivery system and the soft drug approach and provides a variety of examples to embody its concepts. Successful application of such design principles has already been applied to a number of marketed drugs like esmolol; loteprednol etc., and many other candidates like beta blockers, ACE inhibitors, alkylating agents, antimicrobials etc., are also under investigation.