Spirocyclopropyl pyrrolidines as a new series of α-l-fucosidase inhibitors

Advances in the Synthesis of Cyclopropylamines

Cyclopropylamines are an important subclass of substituted cyclopropanes that combine the unique electronic and steric properties of cyclopropanes with the presence of a donor nitrogen atom. In addition to their presence in a diverse array of biologically active compounds, cyclopropylamines are utilized as important synthetic intermediates, particularly in ring-opening or cycloaddition reactions. Consequently, the synthesis of these compounds has constituted a significant research topic, as evidenced by the abundant published synthetic methods. In addition to the widely used Curtius rearrangement, classical cyclopropanation methods have been adapted to integrate a nitrogen function (Simmons-Smith reaction, metal-catalyzed reaction of diazo compounds on olefins, Michael-initiated ring-closure reactions) with significant advances in enantioselective synthesis. More recently, specific methods have been developed for the preparation of the aminocyclopropane moiety (Kulinkovich reactions applied to amides and nitriles, addition to cyclopropenes, metal-catalyzed reactions involving C-H functionalization, ...). The topic of this review is to present the different methods for the preparation of cyclopropylamine derivatives, with the aim of covering the methodological advances as best as possible, highlighting their scope, their stereochemical aspects and future trends.

Synthesis and Evaluation of Biological Activities of Bis(spiropyrazolone)cyclopropanes: A Potential Application against Leishmaniasis

This work focuses on the search and development of drugs that may become new alternatives to the commercial drugs currently available for treatment of leishmaniasis. We have designed and synthesized 12 derivatives of bis(spiropyrazolone)cyclopropanes. We then characterized their potential application in therapeutic use. For this, the in vitro biological activities against three eukaryotic models-S. cerevisiae, five cancer cell lines, and the parasite L. mexicana-were evaluated. In addition, cytotoxicity against non-cancerous mammalian cells has been evaluated and other properties of interest have been characterized, such as genotoxicity, antioxidant properties and, in silico predictive adsorption, distribution, metabolism, and excretion (ADME). The results that we present here represent a first screening, indicating two derivatives of bis(spiropyrazolone)cyclopropanes as good candidates for the treatment of leishmaniasis. They have good specificity against parasites with respect to mammalian cells.

Regiospecific formation of sugar-derived ketonitrone towards unconventional C-branched pyrrolizidines and indolizidines

The synthesis of unprecedented branched pyrrolizidines and indolizidines was accomplished via nitrone chemistry.

Iminosugars Spiro-Linked with Morpholine-Fused 1,2,3-Triazole: Synthesis, Conformational Analysis, Glycosidase Inhibitory Activity, Antifungal Assay, and Docking Studies

Synthesis of iminosugars 1, 2, 3a, and 4a and N-alkyl (ethyl, butyl, hexyl, octyl, decyl, and dodecyl) derivatives 3b-g and 4b-g spiro-linked with morpholine-fused 1,2,3-triazole is described. Conformation of the piperidine ring in each spiro-iminosugar was evaluated by ¹H NMR spectroscopy, and conformational change in N-alkylated compounds 4b-g with respect to parent spiro-iminosugar 4a is supported by density functional theory calculations. Out of 16 new spiro-iminosugars, the spiro-iminosugars 3a (IC₅₀ = 0.075 μM) and 4a (IC₅₀ = 0.036 μM) were found to be more potent inhibitors of α-glucosidase than the marketed drug miglitol (IC₅₀ = 0.100 μM). In addition, 3a (minimum inhibition concentration (MIC) = 0.85 μM) and 4a (MIC = 0.025 μM) showed more potent antifungal activity against Candida albicans than antifungal drug amphotericin b (MIC = 1.25 μM). In few cases, the N-alkyl derivatives showed increase of α-glucosidase inhibition and enhancement of antifungal activity compare to the respective parent iminosugar. The biological activities were further substantiated by molecular docking studies.

Cascade assembling of pyrazolin-5-ones and benzylidenemalononitriles: the facile and efficient approach to medicinally relevant spirocyclopropylpyrazolone scaffold

A new cascade reaction provides a direct transformation of pyrazolin-5-ones and benzylidene-malononitriles by the action of bromine into substituted spirocyclopropylpyrazolones in 60–88% yields. This process can be realized in two variants, namely, (1) by treatment with bromine in the presence of base and (2) by treatment with bromine only with heating. These facile and efficient one-step cascade processes lead to the spirocyclopropylpyrazolone framework, which is present in a perspective class of compounds with prominent pharmacological and physiological activity.

Electrocatalytic stereoselective transformation of aldehydes and two molecules of pyrazolin-5-one into (R*,R*)-bis(spiro-2,4-dihydro-3H-pyrazol-3-one)cyclopropanes

The electrocatalytic transformation of aldehydes and pyrazolin-5-one stereoselectively leads to (R*,R*)-bis(spiro-2,4-dihydro-3H-pyrazol-3-one)cyclopropanes in 65–80% yields.

Diazaspiro-iminosugars and polyhydroxylated spiro-bislactams: synthesis, glycosidase inhibition and molecular docking studies

Synthesis of a new class of iminosugars 1–4 has been reported.

Stereoselective synthesis of medicinally relevant furo[2,3-d]pyrimidine framework by thermal rearrangement of spirocyclic barbiturates

The thermally initiated transformation of substituted spirocyclic barbiturates in DMSO at 100 °C results in the stereoselective formation of medicinally relevant furo[2,3-d]pyrimidines in 50–75% yields.