Indenone Derivatives Research Articles

Innovative indenone-derivative colorimetric fluorescent probe: A approach for copper ion detection in water.

Copper (Cu2+) is a metal chemical element closely related to human life and is widely used in many fields. However, with the discharge of copper wastewater, the water quality will be seriously affected, leading to excessive intake of Cu2+ and a variety of diseases. Hence, there is a pressing need for an effective detection method for Cu2+ in aqueous environments. Leveraging the remarkable attributes of GFP chromophores and indenone derivatives, we have created a novel colorimetric fluorescent probe P-Cu2+, tailored for efficient copper ion detection. The addition of Cu2+ causes the solution to visibly change from colorless to a pronounced yellow, enabling naked-eye detection and offering promise for real sample analysis.

A HMPA-H2O mediated oxygenative carbocyclization of 2-alkynylphenyl-substituted p-quinone methides to indenones.

Herein, we report a transition-metal and base-free protocol to access a wide range of functionalized indenone derivatives through a HMPA-H2O-mediated oxygenative annulation of 2-alkynylphenyl-substituted p-quinone methides. This method worked effectively for most of the p-QMs investigated and the corresponding indenone derivatives were obtained in moderate to good yields. This methodology was further extended to the formal synthesis of one of the resveratrol based natural products, (±)-isopaucifloral F.

Antioxidative Indenone and Benzophenone Derivatives from the Mangrove-Derived Fungus Cytospora heveae NSHSJ-2.

Seven new polyketides, including four indenone derivatives, cytoindenones A-C (1, 3-4), 3'-methoxycytoindenone A (2), a benzophenone derivative, cytorhizophin J (6), and a pair of tetralone enantiomers, (±)-4,6-dihydroxy-5-methoxy-α-tetralone (7), together with a known compound (5) were obtained from the endophytic fungus Cytospora heveae NSHSJ-2 isolated from the fresh stem of the mangrove plant Sonneratia caseolaris. Compound 3 represented the first natural indenone monomer substituted by two benzene moieties at C-2 and C-3. Their structures were determined by the analysis of 1D and 2D NMR, as well as mass spectroscopic data, and the absolute configurations of (±)-7 were determined on the basis of the observed specific rotation value compared with those of the tetralone derivatives previously reported. In bioactivity assays, compounds 1, 4-6 showed potent DPPH· scavenging activities, with EC50 values ranging from 9.5 to 16.6 µM, better than the positive control ascorbic acid (21.9 µM); compounds 2-3 also exhibited DPPH· scavenging activities comparable to ascorbic acid.

Metal-free synthesis of indenone derivatives from ortho-alkynylaryl ketones mediated by the combination of dialkyl phosphonates and CBr4

A novel metal-free synthesis of indenone derivatives mediated by CBr4 and diethyl phosphonate is reported. The methodology has a relatively wide substrate scope and is suitable to access a π-extended indenone and an s-indacene-1,5-dione derivative as well.

Synthesis of Indenone Derivatives by Rh(III)-Catalyzed C-H Functionalization of Sulfoxonium Ylides with 1,3-Diynes.

The transition-metal-catalyzed C-H functionalization of sulfoxonium ylides with alkynes formally participates in [4 + 2] annulations to deliver the naphthol scaffolds. In contrast, herein we disclose the first Rh(III)-catalyzed C-H activation, followed by redox-neutral [3 + 2] annulation of sulfoxonium ylides with 1,3-diynes, which delivers the alkynated indenone derivatives. This protocol features a good functional group tolerance, a broad substrate scope, moderate to excellent yields, and mild reaction conditions. The reaction mechanism was supported through ESI-HRMS by characterizing key intermediates in the catalytic cycle.

Cationic Gold-Catalyzed Intramolecular Cyclization of Substituted 1,5-Diynes to Access Indenone Derivatives.

An efficient intramolecular cyclization reaction was developed to achieve indenone derivatives. The substituted 1,5-diyenes were converted to the corresponding indenones via a gold-catalyzed organic transformation, and moderate to excellent yields of the title molecules were obtained via formation of two C=O and one C-C bonds under mild reaction conditions in one pot.

Photoinduced C–C bond cleavage for the synthesis of 2,4-disubstituted-1-naphthols from indenone derivatives and sulfoxonium ylide

The synthesis of 2,4-disubstituted-1-naphthols has been developed employing photomediated C-C bond cleavage (UV-LED 390 nm) of cyclopropane fused-indanones generated in situ from the reaction between indenones and trimethylsulfoxonium chloride under basic conditions at room temperature. Seventeen substrates were examined in this study. The results showed that indenone precursors containing aryl substituents could smoothly provide the desired products in up to 81% yield.

Synthesis of 2-Chloro-3-amino indenone derivatives and their evaluation as inhibitors of DNA dealkylation repair.

DNA alkylation damage, emanating from the exposure to environmental alkylating agents or produced by certain endogenous metabolic processes, affects cell viability and genomic stability. Fe(II)/2-oxoglutarate-dependent dioxygenase enzymes, such as Escherichia coli AlkB, are involved in protecting DNA from alkylation damage. Inspired by the natural product indenone derivatives reported to inhibit this class of enzymes, and a set of 2-chloro-3-amino indenone derivatives was synthesized and screened for their inhibitory properties against AlkB. The synthesis of 2-chloro-3-amino indenone derivatives was achieved from 2,3-dichloro indenones through addition-elimination method using alkyl/aryl amines under catalyst-free conditions. Using an in vitro reconstituted DNA repair assay, we have identified a 2-chloro-3-amino indenone compound 3o to be an inhibitor of AlkB. We have determined the binding affinity, mode of interaction, and kinetic parameters of inhibition of 3o and tested its ability to sensitize cells to methyl methanesulfonate that mainly produce DNA alkylation damage. This study established the potential of indenone-derived compounds as inhibitors of Fe(II)/2-oxoglutarate-dependent dioxygenase AlkB.

Gold-Catalyzed Cyclization of 2-Alkynylaldehyde Cyclic Acetals via Hydride Shift for the Synthesis of Indenone Derivatives.

An efficient gold-catalyzed cyclization of 2-alkynylaldehyde cyclic acetals has been developed for the synthesis of indenone derivatives. A wide variety of functionalized indenone derivatives can be obtained in good-to-excellent yields. HMBC and NOESY NMR analyses and mechanistic elucidation experiments revealed that the cyclization occurs via a 1,5-H shift. The cyclic acetal group promoted the 1,5-H shift by activating the benzylic C-H bond and preventing the migration of the alkoxy group by tethering both alkoxy groups.

Efficient indenones synthesis via iridium-catalyzed decarboxylative annulation between 2-oxo-2-phenylacetic acids and alkynes

Efficient iridium-catalyzed decarboxylative annulation reactions between 2-oxo-2-phenylacetic acids and alkyne derivatives has been achieved. [IrCp*Cl2]2 with a (CH3OC6H4)3P ligand, AgSbF6 and Cu(OAc)2 additives was the most efficient catalytic system for this transformation. This reaction is suitable for a broad range of alkynes and 2-oxo-2-phenylacetic acids and a variety of indenone derivatives were obtained in medium to high yields. This work provides an efficient approach for the construction of indenones by iridium–catalyzed decarboxylative annulation.

Indenone derivatives as inhibitor of human DNA dealkylation repair enzyme AlkBH3

The mammalian AlkB homologue-3 (AlkBH3) is a member of the dioxygenase family of enzymes that in humans is involved in DNA dealkylation repair. Because of its role in promoting tumor cell proliferation and metastasis of cancer, extensive efforts are being directed in developing selective inhibitors for AlkBH3. Here we report synthesis, screening and evaluation of panel of arylated indenone derivatives as new class of inhibitors of AlkBH3 DNA repair activity. An efficient synthesis of 2,3-diaryl indenones from 2,3-dibromo indenones was achieved via Suzuki-Miyaura cross-coupling. Using a robust quantitative assay, we have obtained an AlkBH3 inhibitor that display specific binding and competitive mode of inhibition against DNA substrate. Finally, we established that this compound could prevent the proliferation of lung cancer cell line and enhance sensitivity to DNA damaging alkylating agent.

Iron‐Catalyzed Synthesis of Indenones through Cyclization of Carboxamides with Alkynes

AbstractThe iron/diphosphine‐catalyzed annulation of a carboxamide possessing a bidentate directing group with an internal alkyne proceeds in the presence of phenylzinc halide as a base at 40 °C to produce a variety of indenone derivatives. The reaction proceeds through iron‐catalyzed C−H bond activation of the carboxamide, followed by insertion of the alkyne into the resulting iron intermediate, and cyclization accelerated by the presence of Lewis acidic ZnII. The reaction of naphthalene and anthraceneamide yields π‐conjugated indenone derivatives.

Facile Synthesis of New Functionalized Triazacyclopenta[cd]indenones Through a Multicomponent Reaction Followed by an Intramolecular Aminolysis

An efficient tandem route to the synthesis of triazacyclopenta[cd]indenone derivatives of the cyclazine family has been developed. Target compounds were obtained in moderate to good yields by Groebke–Blackburn–Bienaymé reaction involving a potassium carbonate promoted intramolecular aminolysis. This in turn will set the stage for a wide application of this useful reaction for the synthesis of structurally diverse polyheterocyclic skeletons containing the imidazo[1,2‐a]pyridine ring.

Copper‐Catalyzed Radical Silylarylation of Ynones with Silanes: En Route to Silyl‐Functionalized Indenones

AbstractA copper‐catalyzed radical silylarylation of ynones with commercially available silanes using DCP (dicumyl peroxide) as an efficient oxidant has been developed. This approach represents an efficient route to silyl‐functionalized indenone derivatives in moderate to good yield. The resulting silyl‐functionalized structures hold potential for further post‐modification to construct complex target molecules. This protocol is distinguished by its excellent selectivity, gram scale‐up ability and broad scope as well as readily available starting materials.magnified image

Iodine‐Mediated Cyclization of ortho‐Alkynylaryl Ketones for the Synthesis of Indenone Derivatives

A new method for the synthesis of indenone derivatives based on the I2‐promoted cyclization of ortho‐alkynylaryl ketones has been developed. This method provides a metal‐free and convenient route for the regioselective synthesis of indenones using ortho‐alkynylaryl ketones with predefined substituents to give indenone products in moderate to good yields.

ChemInform Abstract: π‐Extended Pentalenes: The Revival of the Old Compound from New Standpoints

AbstractReview: [54 refs.

ChemInform Abstract: Thionyl Chloride Mediated Dehydroxylation of 3‐Hydroxyindanones to Indenones.

Abstract3‐Hydroxyindanones, prepared through aldolization of ortho‐diacylbenzenes (I) and (III), undergo SOCl2 mediated dehydroxylation to afford indenone derivatives.

ChemInform Abstract: A Domino Reaction of Tetrahalo‐7,7‐dimethoxybicyclo[2.2.1]heptenyl Alcohols Leading to Indenones and a de novo Synthesis of Ninhydrin Derivatives.

AbstractThe reaction proceeds regioselectively, thus providing 4,5‐substituted indenone derivatives with a 2,3‐dihalo moiety which are further transformed into acetylated ninhydrin derivatives.

π-Extended Pentalenes: The Revival of the Old Compound from New Standpoints.

Polycyclic conjugated systems bearing carbocyclic five-membered rings have attracted much attention due to their novel electronic properties and utility in organic electronic devices. Despite possessing a 4nπ electron periphery, dibenzopentalenes have a planar structure and are fairly stable. Thus, appropriate modifications should provide desirable electronic properties. Recently, we have discovered novel Ni-catalyzed coupling reactions that constitute a versatile new route to dibenzopentalene derivatives from readily available o-bromoethynylbenzenes. Moreover, we developed another dibenzopentalene synthesis using indenone derivatives as important intermediates. These methods are applicable to π-extended pentalene derivatives possessing various functional groups and aromatic ring systems. Among them, a dinaphthylpentalene derivative shows a high hole mobility (1.8 × 10(-3) cm(2) V(-1) s(-1) ) for an amorphous material. Furthermore, this is the first pentalene derivative that can be employed as a p-type material for organic heterojunction photovoltaic cells (PCE = 0.94%, V(OC) = 0.96 V) and as organic thin-film semiconductors.

ChemInform Abstract: Palladium‐Catalyzed Intramolecular Asymmetric C—H Functionalization/Cyclization Reaction of Metallocenes: An Efficient Approach Toward the Synthesis of Planar Chiral Metallocene Compounds.

AbstractThe synthesis of the title compounds is achieved by intramolecular cyclization to form indenone derivatives in high yields with excellent enantioselectivity.