Synthesis and biological activity of pyrrole, pyrroline and pyrrolidine derivatives with two aryl groups on adjacent positions

Rh(ii)-Catalyzed formation of pyrrolo[2,3-b]quinolines from azide-methylenecyclopropanes and isonitriles

Azide-methylenecyclopropanes underwent an intermolecular cyclization with isonitriles catalyzed by a Rh^IIcomplex to produce a series of pyrrolo[2,3-b]quinolines in good yields. Moreover, synthetic applications to construct useful heterocycles have also been achieved.

An MEDT study of the carbenoid-type [3 + 2] cycloaddition reactions of nitrile ylides with electron-deficient chiral oxazolidinones

A combination of the bonding evolution theory and non-covalent interactions analyses of TSs makes it possible to characterise both the carbenoid-type 32CA reaction between a NY and a chiral oxazolidinone, and the diastereoselectivity experimentally observed.

Selective synthesis of functionalized pyrroles from 3-aza-1,5-enynes

Three kinds of functionalized pyrroles were selectively synthesized from 3-aza-1,5-enynes via cyclization reactions.

Synthesis of 2-fluoro-2-pyrrolines via tandem reaction of α-trifluoromethyl-α,β-unsaturated carbonyl compounds with N-tosylated 2-aminomalonates

A simple base-mediated synthesis of synthetically valuable 2-fluoro-2-pyrrolines from α-trifluoromethyl-α,β-unsaturated carbonyl compounds and N-tosylated 2-aminomalonates was developed.

β-Cyclodextrin as a recyclable catalyst: aqueous phase one-pot four-component synthesis of polyfunctionalized pyrroles

An elegant, mild and straightforward methodology was explored for the first time towards the synthesis of polyfunctionalized pyrroles using β-cyclodextrin as a reusable supramolecular catalyst in aqueous medium.

Controlled TfOH- or AuCl-catalyzed cycloisomerization and tandem hydrolytic defluorination of 1,2-allenyl perfluoroalkyl ketones

An efficient TfOH- or AuCl-catalyzed cycloisomerization reaction of easily availablen-perfluoroalkyl 1,2-allenyl ketones occurring smoothly to form 2-perfluoroalkyl furans or 2-furyl perfluoroalkyl ketones has been reported.

Synthesis of novel 1,5-disubstituted pyrrolo[1,2-a]quinazolines and their evaluation for anti-bacterial and anti-oxidant activities

A new series of 1,5-disubstituted pyrrolo[1,2-a]quinazoline derivatives were prepared from 2-chloro-4-substituted quinazolines, propargyl alcohol, and secondary amines through novel multi-component reactions.

An isocyanide insertion approach to substituted pyrrolo[2,3-b]quinolines under metal-free and azide-free conditions

An isocyanide insertion approach to construct the pyrrolo[2,3-b]quinoline skeleton by an I₂/CHP mediated reaction of aminome-thylenecyclo-propanes (amino-MCPs) is developed.

TfOH-catalyzed domino cycloisomerization/hydrolytic defluorination of 2,3-allenyl perfluoroalkyl ketones

A unique TfOH-catalyzed domino cycloisomerization/hydrolytic defluorination reaction of easily available n-perfluoroalkyl allenones in the presence of H2O providing furanyl perfluoroalkyl ketones has been developed. The (18)O-labelling experiments confirmed that the oxygen atom of the carbonyl group in the final products originates from water.

Crystal structure of 4'-(2-meth-oxy-quinolin-3-yl)-1'-methyl-dispiro-[indan-2,2'-pyrrolidine-3',3''-indoline]-1,3,2''-trione

In the title compound, C₃₀H₂₃N₃O₄, the central 1-methyl­pyrrolidine ring adopts a twist conformation on the N—CH₂ bond. The pyrrolidin-2-one ring of the indolin-2-one ring system also has a twist conformation on the C—C bond involving the spiro C atom and the carbonyl C atom. The five-membered ring of the indene-1,3-dione moiety has an envelope conformation with the spiro C atom as the flap. The quinoline ring system adopts an almost planar conformation (r.m.s. deviation = 0.04 Å). The mean planes of the indolin-2-one ring system, the indene-1,3-dione ring system and the the quinoline ring system are inclined to the mean plane of the central 1-methyl­pyrrolidine ring by 77.97 (7), 86.98 (7) and 46.58 (6)°, respectively. In the crystal, mol­ecules are linked via N—H⋯N hydrogen bonds, forming chains along the b axis. The chains are linked via a number of C—H⋯O hydrogen bonds, and C—H⋯π and π–π inter­actions [inter-centroid distance = 3.7404 (9) Å], forming a three-dimensional network.

Crystal structure of 15-(2-chloro-phen-yl)-6b-hy-droxy-17-methyl-6b,7,16,17-tetra-hydro-7,14a-methanona-phtho[1',8':1,2,3]pyrrolo-[3',2':8,8a]azuleno[5,6-b]quinolin-14(15H)-one

In the title compound, C34H25ClN2O2, the fused pyrrolidine ring adopts an envelope conformation with the N atom as the flap. The two adjacent cyclo-pentane rings also adopt envelope conformations. The mean plane of the pyrrolidine ring makes dihedral angles of 40.53 (10) and 80.23 (10)° with the mean planes of the cyclo-pentane rings. The dihedral angle between the mean planes of the cyclo-pentane rings is 46.71 (9)°. An intra-molecular O-H⋯N hydrogen bond is observed. In the crystal, mol-ecules are linked by C-H⋯O, C-H⋯N and C-H⋯π inter-actions, forming a layer parallel to (10-2).

Stereospecific cyclization reaction of alkenyl esters and amides of ethenetricarboxylate

The stereospecificity of the cyclization reaction of (E)- and (Z)-2-alkenyl esters and amides of ethenetricarboxylate has been examined. The reaction of (E)/(Z)-2-butenyl esters with AlCl3 or FeCl3 gave trans-substituted chlorinated γ-lactone diastereomers stereospecifically. (E)/(Z)-2-butenyl and pentenyl amides undergo an intramolecular ene reaction at room temperature gradually. At 80 °C, the (Z)-alkenyl amides were transformed to cis-substituted ene adducts and the (E)-amides were transformed to cis- and trans-substituted ene adduct mixtures. The reaction of (E)/(Z)-2-alkenyl amides with ZnI2 gave trans-substituted γ-lactam diastereomers stereospecifically along with the ene adducts.

Copper-catalyzed condensation of imines and α-diazo-β-dicarbonyl compounds: modular and regiocontrolled synthesis of multisubstituted pyrroles

The Cu-catalyzed condensation of ketimines and diazodicarbonyl compounds enables the rapid and regiocontrolled synthesis of pharmaceutically relevant multisubstituted pyrroles.

In the presence of a copper(ii) catalyst, enolizable imines bearing various N-substituents and α-diazo-β-ketoesters undergo denitrogenative and dehydrative condensation to afford highly substituted pyrroles in moderate to good yields with exclusive regioselectivity. The reaction likely involves nucleophilic addition of the imine nitrogen to a copper carbenoid, tautomerization of the resulting azomethine ylide to an α-enaminoketone, and a subsequent enamine–ketone cyclocondensation. With Yb(OTf)₃ as a unique cocatalyst, α-diazo-β-diketones also participate in the same condensation reaction. The present reaction is applicable to acyclic, exocyclic, and endocyclic imines with tolerance of a broad range of functional groups and heterocyclic moieties, thus opening a new convenient route for the synthesis of the lamellarin family of natural products.

Photocatalytic generation of N-centered hydrazonyl radicals: a strategy for hydroamination of β,γ-unsaturated hydrazones

A visible-light photocatalytic generation of N-centered hydrazonyl radicals has been accomplished for the first time. This approach allows efficient intramolecular addition of hydrazonyl radical to terminal alkenes, thus providing hydroamination and oxyamination products in good yields. Importantly, the protocol involves deprotonation of an N-H bond and photocatalytic oxidation to an N-centered radical, thus obviating the need to prepare photolabile amine precursors or the stoichiometric use of oxidizing reagents.

Multicomponent one-pot synthesis of highly-functionalized pyrrole-3-carbonitriles in aqueous medium and their computational study

A one-pot green protocol involving four-components in aqueous medium is developed to synthesize highly-functionalized pyrroles in good yields. Two of the newly synthesized compounds were subjected to in silico analysis on the Pharm Mapper web-server and the human mitogen-activated protein kinase1 (MEK1) enzyme was identified as a potential target protein for these compounds. For target validation, MEK-1 inhibition was performed with two representative compounds (5g and 5h) using docking simulations. These functionalized pyrroles were also tested for their respective IC50 values on human cancer cell lines to evaluate their biocompatibility. Several of these functionalized pyrrole molecules were found to possess higher growth inhibition activity than standard doxorubicin and cisplatin.

Cu-based carbene involved in a radical process: a new crossover reaction to construct γ-peroxy esters and 1,4-dicarbonyl compounds

Herein, a novel crossover reaction of Cu-based carbene, olefin, and tert-butyl hydroperoxide (TBHP) was well developed, leading to γ-peroxy esters and 1,4-dicarbonyl compounds.

Organocatalytic multicomponent synthesis of polysubstituted pyrroles from 1,2-diones, aldehydes and arylamines

We have developed an organocatalyzed three-component reaction of 1,2-diones, aldehydes and arylamines, which provides an efficient approach to access polysubstituted pyrroles.

An efficient Au(i) catalyst for double hydroarylation of alkynes with heteroarenes

Double hydroarylation of alkynes with heteroarenes under mild conditions catalyzed by Au(i) are now reported.

Facile synthesis and characterization of bio-organometallic compounds and their biological activity contour against human pathogens

We have reported the synthesis of novel di & trisubstituted pyrroles and their biological activity.