A detailed investigation of the multicomponent reaction of salicylaldehyde, ethyl acetoacetate and isocyanides under microwave heating

The status of isocyanide-based multi-component reactions in Iran (2010-2018)

Isocyanides as key intermediates and magic reactants have been widely applied in organic reactions for direct access to a broad spectrum of remarkable organic compounds. Although the history of these magical compounds dates back more than 100 years, it still has been drawing widespread attention of chemists who confirmed their versatility and effectiveness. Because of their wide spectrum of pharmacological, industrial and synthetic applications, many reactions with the utilization of isocyanides are reported in the literature. In this context, Iranian scientist played a significant role in the growth of isocyanides chemistry. The present review article covers literature from the period starting from 2010 onward and encompasses new synthetic routes and organic transformation involving isocyanides by Iranian researchers. During this period, a diverse range of isocyanide-based multi-component reactions (I-MCRs) has been reported such as a new modification of Ugi, post-Ugi, Passerini and Groebke-Blackburn-Bienayme condensation reactions, isocyanide-based [1 + 4] cycloaddition reactions, isocyanide-acetylene-based MCRs, isocyanide and Meldrum's acid-based MCRs, several unexpected reactions besides green mediums and novel catalytic systems for the synthesis of diverse kinds of pharmaceutically and industrially remarkable heterocyclic and linear organic compounds. This review also emphasizes the neoteric applications of I-MCR for the synthesis of valuable peptide and pseudopeptide scaffolds, enzyme immobilization and functionalization of materials with tailorable properties that can play important roles in the plethora of applications.

Peroxycarbenium Ions as the "Gatekeepers" in Reaction Design: Assistance from Inverse Alpha-Effect in Three-Component β-Alkoxy-β-peroxylactones Synthesis

Stereoelectronic interactions control reactivity of peroxycarbenium cations, the key intermediates in (per)oxidation chemistry. Computational analysis suggests that alcohol involvement as a third component in the carbonyl/peroxide reactions remained invisible due to the absence of sufficiently deep kinetic traps needed to prevent the escape of mixed alcohol/peroxide products to the more stable bisperoxides. Synthesis of β-alkoxy-β-peroxylactones, a new type of organic peroxides, was accomplished by interrupting a thermodynamically driven peroxidation cascade. The higher energy β-alkoxy-β-peroxylactones do not transform into the more stable bisperoxides due to the stereoelectronically imposed instability of a cyclic peroxycarbenium intermediate as a consequence of amplified inverse alpha-effect. The practical consequence of this fundamental finding is the first three-component cyclization/condensation of β-ketoesters, H₂ O₂ , and alcohols that provides β-alkoxy-β-peroxylactones in 15-80 % yields.

Design, Synthesis, Anticancer Evaluation and Docking Studies of Novel Heterocyclic Derivatives Obtained via Reactions Involving Curcumin

Curcumin, a widely utilized flavor and coloring agent in food, has been shown to demonstrate powerful antioxidant, antitumor promoting and anti-inflammatory properties in vitro and in vivo. In the present work, synthesis of new heterocyclic derivatives based on Curcumin was studied. Compound 3 was synthesized via the reaction of furochromone carbaldehyde (1) with Curcumin (2) using pipredine as catalyst. Also, novel, 4,9-dimethoxy-5H-furo [3, 2-g] chromen-5-one derivatives 4a–d, 6a–d, 7, 8a–d, 9 and 10 were synthesized by the reactions of furochromone carbaldehyde (1) with different reagents (namely: appropriate amine 3a–d, appropriate hydrazine 5a–d, hydroxylamine hydrochloride, urea/thiourea, malononitrile, malononitrile with hydrazine hydrate). The structure of the synthesized products had been confirmed from their spectroscopic data (IR, ¹H-NMR, ¹³C-NMR and mass spectra). In the present investigation, the newly synthesized products were screened using the MTT colorimetric assay for their in vitro inhibition capacity in two human cancer cell lines (hepatocellular carcinoma (HEPG2) and breast cancer (MCF-7) as well as the normal cell line (human normal melanocyte, HFB4) in comparison to the known anticancer drugs: 5-flurouracil and doxorubicin. The anticancer activity results indicated that the synthesized products 4c and 8b showed growth inhibition activity against HEPG2 cell line and synthesized products 4b and 8a showed growth inhibition activity against MCF-7, but with varying intensities in comparison to the known anticancer drugs, 5-flurouracil and doxorubicin. Cyclin dependent kinase 2 (CDK2), a major cell cycle protein, was identified as a potential molecular target of Curcumin. Furthermore, Curcumin induced G1 cell cycle arrest, which is regulated by CDK2 in cancer cells. Therefore, we used molecular modelling to study in silico the possible inhibitory effect of CDK2 by Curcumin derivatives as a possible mechanism of these compounds as anticancer agents. The molecular docking study revealed that compounds 4b, 8a and 8b were the most effective compounds in inhibiting CDk2, and, this result was in agreement with cytotoxicity assay.

Diastereoselective Synthesis of Symmetrical and Unsymmetrical Tetrahydropyridines Catalyzed by Bi(III) Immobilized on Triazine Dendrimer Stabilized Magnetic Nanoparticles

Unsymmetrical 1,2,5,6-tetrahydropyridine-3-carboxylates were obtained for the first time from a five-component Fe₃O₄@TDSN-Bi(III)-catalyzed reaction of aryl aldehydes, aryl amines, and ethyl acetoacetate. This magnetically separable catalyst enabled the selective incorporation of two different aryl amines or two different aryl aldehydes into the product, and provided excellent yields, short reaction times, mild reaction conditions, satisfactory catalyst recyclability, and low catalyst loading.

1,3,5-Tris(2-hydroxyethyl)isocyanurate functionalized graphene oxide: a novel and efficient nanocatalyst for the one-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones

The preparation and characterization of a novel 1,3,5-tris(2-hydroxyethyl)isocyanurate functionalized graphene oxide (GO–THEIC) nanomaterial and its catalytic application for the Biginelli reaction are described.

Synthesis of 3-[(coumarinyl)carbonyl]-3a,8b-dihyroindeno[1,2-b]pyrrole-4(1H)-ones and their conversion to coumarin bearing spiro[isobenzofuran-1,2′-pyrrole] moiety compounds via oxidative cleavage reaction

The synthesis of substituted coumarin derivatives bearing indenopyrrole and spiro[isobenzofuran-1,2′-pyrrole] in a four-component sequential reaction and following oxidative cleavage reaction.