Novel fluorinated pyrrolo[1,2-a]pyrazine-2,6-dione derivatives: Synthesis and anticonvulsant evaluation in animal models of epilepsy

1-Methylimidazole as an Organic Catalyst for [3+3]-Cyclodimerization of Acylethynylpyrroles to Bis(acylmethylidene)dipyrrolo[1,2-a:1′,2′-d]pyrazines

Acylethynylpyrroles, now readily available by the cross-coupling of pyrroles with acylbromoacetylenes in solid Al2O3 media, in the presence of 1-methylimidazole underwent unprecedentedly easy (40–45 °C) cyclodimerization into bis(acylmethylidene)dipyrrolo[1,2-a:1′,2′-d]pyrazines in up to 51% yield. Some other organic and inorganic basic catalysts can also trigger this cyclodimerization, but less efficiently.

PIFA-promoted intramolecular oxidative cyclization of pyrrolo- and indolo[1,2-a]quinoxalino-appended porphyrins: an efficient synthesis of meso,β-pyrrolo- and indolo[1,2-a]quinoxalino-fused porphyrins

We have developed an efficient protocol for the synthesis of meso,β-pyrrolo- and indolo[1,2-a]quinoxalino-fused porphyrin systems 7-9 by PIFA-promoted intramolecular oxidative cyclization of easily accessible meso-pyrrolo- and indolo[1,2-a]quinoxalino-appended porphyrins 6a-j. The absorption spectra of meso,β-pyrrolo- and indolo[1,2-a]quinoxalino-fused porphyrins 7-9 displayed bathochromic shifted (100-150 nm) and broadened Soret bands and Q bands in addition to intense band near IR region. The indolo[1,2-a]quinoxalino-fused porphyrin 9bZn with lower fluorescence quantum yield (0.003) and reduced energy gap (∼1.3 eV) was found to sensitize singlet oxygen effectively.

Recent advancement in the discovery and development of anti-epileptic biomolecules: An insight into structure activity relationship and Docking

Although there have been many advancements in scientific research and development, the cause of epilepsy still remains an open challenge. In spite of high throughput research in the field of anti-epileptic drugs, efficacy void is still prevalent before the researchers. Researchers have persistently been exploring all the possibilities to curb undesirable side effects of the anti-epileptic drugs or looking for a more substantial approach to diminish or cure epilepsy. The drug development has shown a hope to medicinal chemists and researchers to carry further research by going through a substantial literature survey. This review article attempts to describe the recent developments in the anti-epileptic agents, pertaining to different molecular scaffolds considering their structure-activity relationship, docking studies and their mechanism of actions.

Anticonvulsant and antinociceptive activity of new amides derived from 3-phenyl-2,5-dioxo-pyrrolidine-1-yl-acetic acid in mice

The aim of the present experiments was to examine the anticonvulsant and antinociceptive activity of five new amides derived from 3-phenyl-2,5-dioxo-pyrrolidine-1-yl-acetic acid in animal models of seizures and pain. The antiseizure activity was investigated in three acute models of seizures, namely, the maximal electroshock (MES), the subcutaneous pentylenetetrazole (scPTZ), and 6Hz psychomotor seizure tests in mice. The antinociceptive properties were estimated in the formalin model of tonic pain, and in the oxaliplatin-induced neuropathic pain model in mice. Considering drug safety evaluation, acute neurological toxicity was determined in the rotarod test. Three tested compounds (3, 4, and 7) displayed a broad spectrum of anticonvulsant activity and showed better protective indices than those obtained for MES/scPTZ/6Hz active reference drug - valproic acid. Furthermore, three compounds (3, 4, and 6) demonstrated a significant antinociceptive effect in the formalin test, as well as antiallodynic activity in the oxaliplatin-induced neuropathic pain model. Among the tested agents, compounds 3 and 4 displayed not only antiseizure properties, but also collateral prominent analgesic properties. The in vitro binding study indicated that the plausible mechanism of action of chosen compound (4) was the influence on neuronal voltage-sensitive sodium (site 2) and L-type calcium channels.

Piperazine scaffold: A remarkable tool in generation of diverse pharmacological agents

Piperazine is one of the most sought heterocyclics for the development of new drug candidates. This ring can be traced in a number of well established, commercially available drugs. Wide array of pharmacological activities exhibited by piperazine derivatives have made them indispensable anchors for the development of novel therapeutic agents. The review herein highlights the therapeutic significance of piperazine derivatives. Various therapeutically active piperazine derivatives developed by several chemists are reported here.

Ambient temperature synthesis of β,β′-fused nickel(ii) pyrrolo[1,2-a]pyrazinoporphyrins via a DBSA-catalyzed Pictet–Spengler approach

Synthesis of novel β,β′-fused nickel(ii) pyrrolo[1,2-a]pyrazinoporphyrins is accomplished for the first time at ambient temperature via a DBSA-catalyzed Pictet–Spengler approach.