4-Aminopiperidine derivatives as a new class of potent cognition enhancing drugs

Piperazines as nootropic agents: New derivatives of the potent cognition-enhancer DM235 carrying hydrophilic substituents

The piperazine ring of the potent nootropic drug DM235 has been decorated with H-bond donor and acceptor groups (CH₂OH, CH₂OMe, CH₂OCOMe, COOEt); the aim was to insert new functional groups, suitable for further chemical manipulation. The influence of these modifications on nootropic activity was assessed by means of the mouse passive avoidance test; some of the newly synthesized molecules (alcohol 7b, acetate 8b and ester 10d) showed interesting in vivo potency. This makes it possible to use these functional groups for adding other residues, in order to increase molecular diversity, or for anchoring a biotin group, to obtain compounds useful to capture the biological target. Moreover, the new compounds will improve our knowledge of structure activity relationships of this family of drugs.

Synthesis and pharmacological evaluation of donepezil-based agents as new cholinesterase/monoamine oxidase inhibitors for the potential application against Alzheimer's disease

In a continuing effort to develop multitargeted compounds as potential treatment agents against Alzheimer's disease (AD), a series of donepezil-like compounds were designed, synthesized and evaluated. In vitro studies showed that most of the designed compounds displayed potent inhibitory activities toward AChE, BuChE, MAO-B and MAO-A. Among them, w18 was a promising agent with balanced activities, which exhibited a moderate cholinesterase inhibition (IC₅₀, 0.220 μM for eeAChE; 1.23 μM for eqBuChE; 0.454 μM for hAChE) and an acceptable inhibitory activity against monoamine oxidases (IC₅₀, 3.14 μM for MAO-B; 13.4 μM for MAO-A). Moreover, w18 could also be a metal-chelator, and able to cross the blood-brain barrier with low cell toxicity on PC12 cells. Taken together, these results suggested that w18 might be a promising multitargeted compound for AD treatment.

Unifi nootropics from the lab to the web: a story of academic (and industrial) shortcomings

This paper is a review of the work of my former academic group of research in the past 15 years, in the field of cognition enhancers (also called nootropics) that identified two very potent molecules: Unifiram and Sunifiram that for a variety of reasons were not protected by a patent. Some 12 years after their disclosure (2000) I casually found that on the web, there were dozens of sites offering Unifiram and Sunifiram as drugs that improve cognition in healthy individuals even if only few preclinical studies were done and their long-term toxicity was unknown.

Pharmacological characterization of DM232 (unifiram) and DM235 (sunifiram), new potent cognition enhancers

DM232 (unifiram) and DM235 (sunifiram) are potent cognition-enhancers, which are four order of magnitude more potent than piracetam. These compounds, although not showing affinity in binding studies for the most important central receptors or channels, are able to prevent amnesia induced by modulation of several neurotransmission systems. These compounds are able to increase the release of acetylcholine from rat cerebral cortex, and, as far as unifiram is concerned, to increase the amplitude of fEPSP in rat hippocampal slices. In vitro experiments, performed on hippocampal slices, also supported the hypothesis of a role of the AMPA receptors for the cognition-enhancing properties of unifiram and sunifiram.

Structure–activity relationship studies on unifiram (DM232) and sunifiram (DM235), two novel and potent cognition enhancing drugs

Structure-activity relationships on two novel potent cognition enhancing drugs, unifiram (DM232, 1) and sunifiram (DM235, 2), are reported. Although none of the compounds synthesised reached the potency of the parent drugs, some fairly active compounds have been identified that may represent new leads to develop other cognition enhancing drugs. An interesting result of this research is the identification of two compounds (13 and 14) that are endowed with amnesing activity (the opposite of the activity of the original molecules) and are nearly equipotent to scopolamine. Moreover, two compounds of the series (5 and 6) were found endowed with analgesic activity on a rat model of neuropathic pain at the dose of 1 mg/kg.