A New Four‐Component Reaction for the Synthesis of Spiro[4H‐indeno[1,2‐b]pyridine‐4,3′‐[3H]indoles]

A new four‐component synthesis of spiro[4H‐indeno[1,2‐b]pyridine‐4,3′‐[3H]indoles] and spiro[acenaphthylene‐1(2H),4′‐[4H‐indeno[1,2‐b]pyridines] by the reaction of indane‐1,3‐dione, 1,3‐dicarbonyl compounds, isatins (=1H‐indole‐2,3‐diones) or acenaphthylene‐1,2‐dione, and AcONH₄ in refluxing toluene in the presence of a catalytic amount of pyridine is reported.     

Diastereoselective Synthesis of (Z)‐6‐(2‐Oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐diones

Two efficient and diastereoselective procedures for the synthesis of (Z)‐6‐(2‐oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐diones by aldol‐crotonic condensation of 1,3‐dimethyl‐3a,9a‐diphenyl‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐dione with isatins under acidic or basic catalysis are reported. Isomerization in (Z)‐7‐(1‐allyl‐2‐oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐1,3‐dimethyl‐3a,9a‐diphenyl‐1,3a,4,9a‐tetrahydroimidazo[4,5‐e]thiazolo[2,3‐c]‐1,2,4‐triazin‐2,8(3H,7H)‐dione was observed under basic conditions.     

Two isomeric 2‐[4‐chloro‐2‐fluoro‐5‐(prop‐2‐ynyloxy)phenyl]hexahydro­isoindole‐1,3‐dione compounds

The molecular structures of 2‐[4‐chloro‐2‐fluoro‐5‐(prop‐2‐ynyloxy)phenyl]‐1,3,4,5,6,7‐hexahydro­isoindole‐1,3‐dione, C₁₇H₁₃ClFNO₃, (I), and the isomeric compound 2‐[4‐chloro‐2‐fluoro‐5‐(prop‐2‐ynyloxy)phenyl]‐cis‐1,3,3a,4,7,7a‐hexahydro­isoindole‐1,3‐dione, (II), are, as anticipated, significantly different in their conformations and in the distances between the farthest two atoms. The six‐membered ring of the 1,3,4,5,6,7‐hexahydro­isoindole‐1,3‐dione moiety in (I) adopts a half‐chair conformation. The dihedral angle between the five‐membered dione ring of (I) and the benzene ring is 50.96 (7)°. The six‐membered ring of the cis‐1,3,3a,4,7,7a‐hexahydro­isoindole‐1,3‐dione moiety in (II) adopts a boat conformation. The dihedral angle in (II) between the five‐membered dione ring and the benzene ring is 61.03 (13)°. In the crystal structures, the molecules are linked by C—H⋯O hydrogen bonds and weak π–π interactions. Compound (I) is a much more potent herbicide than (II). The Cl⋯H distances between the farthest two atoms in (I) and (II) are 11.37 and 9.97 Å, respectively.     

Spiro[4H–pyran‐3,3′‐oxindoles] Derived from 9,10‐dihydroacridine

Reaction 6H‐pyrrolo[3,2,1‐de ]acridine‐1,2‐dione ( 7 ) with cyclic 1,3‐dicarbonyl compounds in the presence of malononitrile or ethyl cyanoacetate generates spiro[4H‐pyran‐3,3′‐oxindoles] 8 .     

Spiro[4H‐2,3‐dihydropyran‐3,3′‐oxindoles] derived from 1,2,3,4‐tetrahydroquinoline

Knoevenagel condensation of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione 3 with aryl cyanomethyl ketones 9 generates 3‐(aroyl(cyano)methylidene)oxindoles 10 that react with cyclic 1,3‐diketones 11 to generate polycyclic hemiacetal spiro[4H‐2,3‐dihydropyran‐3,3′‐oxindoles] 13 .     

Synthesis and heterocyclizations of 3‐alkynyl‐6,8‐dimethylpyrimido‐[4,5‐c]pyridazine‐5,7(6H,8H)‐diones and their lumazine analogues

Synthesis of some condensed pyrrolo‐, thieno‐, furo‐, pyrido‐ and pyranopteridines as well as isomeric pyrrolo‐ and thienopyrimido[4,5‐c]pyridazines from alkynyl derivatives of 6,8‐dimethylpyrimido[4,5‐c]pyridazine‐5,7(6H,8H)‐dione and 1,3‐dimethyllumazine is represented.     

Synthesis of Hexahydrospiro[pyrazolo[3,4‐b]quinoline‐4,1′‐pyrrolo[3,2,1‐ij]quinoline‐2′,5(1H,4′H)‐diones] from 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione Using Fe3O4@Cu(OH)x as a Nanocatalyst

The tricyclic isatin, 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione, undergoes three‐component, one‐pot reactions with 1‐aryl‐3‐methylpyrazole‐5‐amines and cyclohexane‐1,3‐diones producing hexacyclic spiro products, hexahydrospiro[pyrazolo[3,4‐b]quinoline‐4,1‐pyrrolo[3,2,1‐ij]quinoline‐2′,5(1H,4′H)‐diones]. Comparable spiro condensation products are also obtained using 4‐hydroxy‐2H‐1‐benzopyran‐2‐one in place of cyclohexane‐1,3‐diones.     

An Efficient Five‐Component Reaction for the Synthesis of 4,4′‐((2‐Oxoindoline‐3,3‐diyl)bis(methylene))bis(2‐aryl‐1H‐pyrrolo[3,4‐c]quinoline‐1,3(2H)‐dione) Derivatives

An efficient cascade process five‐component reaction of isatins and 3‐oxo‐N‐arylbutanamide for the synthesis of 4,4′‐((2‐oxoindoline‐3,3‐diyl)bis(methylene))bis(2‐aryl‐1H‐pyrrolo[3,4‐c]quinoline‐1,3(2H)‐dione) derivatives was reported under mild condition. The advantages of this strategy are easy to obtain raw materials, convenient one‐pot procedure, and simple operation.     

Convenient One‐Pot Room Temperature Synthesis of 2‐(trifluoromethyl)‐1,2,3,4,7,8‐hexahydroquinolin‐5(6H)‐one derivatives via Catalyst‐Free Multicomponent Reactions

This paper describes an efficient approach for the synthesis of 2‐(trifluoromethyl)‐1,2,3,4,7,8‐hexahydroquinolin‐5(6H)‐one derivatives via a one‐pot four‐component reaction of aromatic aldehyde, 5,5‐dimethylcyclohexane‐1,3‐dione, 4,4,4‐trifluoro‐1‐(thien‐2‐yl)butane‐1,3‐dione, and NH₄OAc with excellent yields at room temperature. In this synthesis, the trifluoromethyl was efficiently introduced in hexahydroquinoline structure, and they may be valuable the drug candidates. This approach also offered several other advantages, such as catalyst‐free, mild conditions, and simple experimental operation.     

Four 7‐aryl‐substituted pyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐diones: similar molecular structures but different crystal structures

Molecules of 1,3‐dimethyl‐7‐(4‐methylphenyl)pyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₁₆H₁₅N₃O₂, (I), are linked by paired C—H...O hydrogen bonds to form centrosymmetric R₂²(10) dimers, which are linked into chains by a single π–π stacking interaction. A single C—H...O hydrogen bond links the molecules of 7‐(biphenyl‐4‐yl)‐1,3‐dimethylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₂₁H₁₇N₃O₂, (II), into C(10) chains, which are weakly linked into sheets by a π–π stacking interaction. In 7‐(4‐fluorophenyl)‐3‐methylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₁₄H₁₀FN₃O₂, (III), an N—H...O hydrogen bond links the molecules into C(6) chains, which are linked into sheets by a π–π stacking interaction. The molecules of 7‐(4‐methoxyphenyl)‐3‐methylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₁₅H₁₃N₃O₃, (IV), are also linked into C(6) chains by an N—H...O hydrogen bond, but here the chains are linked into sheets by a combination of two independent C—H...π(arene) hydrogen bonds.     

Spiro[4H‐pyran‐3,3′‐oxindoles] Derived from 1,2,3,4‐Tetrahydroquinoline

Three‐component reactions of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione with malononitrile, or ethyl cyanoacetate, and cyclic six‐membered or a five‐membered 1,3‐diketone, produce spiro[4H‐pyran‐3,3′‐oxindoles].     

2‐Phenyl­malonpiperadide and 2‐phenyl­malonmorpholide

The structures of 2‐phenyl­malonpiperadide [systematic name: 2‐phenyl‐1,3‐bis­(piperidin‐1‐yl)­propane‐1,3‐dione, C₁₉H₂₆N₂O₂, (I)] and 2‐phenyl­malonmorpholide [systematic name: 1,3‐dimorpholino‐2‐phenyl­propane‐1,3‐dione, C₁₇H₂₂N₂O₄, (II)], have been determined and both their molecular conformations and packing arrangements compared. Although chemically similar, compounds (I) and (II) exhibit different molecular conformations. The only general conformational similarities are that their respective carbonyl groups are orientated in the same direction and the heterocyclic rings exist in the chair arrangement. General similarities in the packing arrangements arise due to both compounds having the same space group (P2₁2₁2₁) and a similar alignment of their phenyl‐substituted backbone with respect to the c axis. Similar C—H⋯O hydrogen‐bonding associations are listed for the carbonyl O atoms, while only one of the morpholine O atoms is involved in any such association.     

Synthesis of new 3‐(4‐oxo‐4H‐chromen‐3‐yl)‐3a,6a‐dihydropyrrolo[3,4‐d]isoxazole‐4,6‐dione derivatives by 1,3‐dipolar cycloaddition reaction

A series of new 3‐(4‐oxo‐4H‐chromen‐3‐yl)‐3a,6a‐dihydropyrrolo[3,4‐d]isoxazole‐4,6‐dione have been synthesized by the reaction of N‐arylmaleimides with nitrile oxide, prepared from α‐chloro‐4‐oxo‐4H‐chromen‐carbaldehyde oximes in situ through 1,3‐dipolar cycloaddition reaction. The structures of all new compounds were confirmed by elemental analysis, ir,¹H nmr and mass spectral data.     

5‐Fluoro‐1‐octanoyl­uracil

The crystal structure of 5‐fluoro‐1‐octanoyl­uracil [5‐fluoro‐1‐octanoyl­pyrimidine‐2,4(1H,3H)‐dione, C₁₂H₁₇FN₂O₃], a lipophilic prodrug of 5‐fluoro­uracil, is described. The 5‐fluoro­pyrimidine‐2,4(1H,3H)‐dione moiety is similar to the known structure of 1‐acetyl‐5‐fluoro­uracil. The 1‐octanoyl group and the 5‐fluoro­uracil moiety are essentially coplanar, with the octanoyl carbonyl group oriented towards the the ring C—H group and away from the nearer ring carbonyl group. The torsion angle C—N—C—O (from the ring CH group to the octanoyl carbonyl group) of 9.2 (2)° is similar to the corresponding torsion angles reported for 1‐acetyl‐5‐fluoro­uracil (17.3 and 1.6°) and 1,3‐di­acetyl‐5‐fluoro­uracil (8.8°).     

Synthesis of heterocyclic nitrogen derivatives from aryl‐1,4‐benzoquinones

Treatment of 2‐aryl‐3,6‐bis(arylamino)‐1,4‐benzoquinones 2a‐h with different acid chlorides, namely acetyl, phenylacetyl and chloroacetyl chloride yields 3a,7a‐dihydropyrrolo[2,3‐f]indole‐2,6‐dione 3, 5‐(N‐phenylacetylarylamino)‐3‐phenylindole‐2,6‐dione 4 and 3‐chloro‐5‐(N‐chloroacetylarylamino)indole‐2,6‐dione 5 respectively. Stirring 2‐aryl‐1,4‐benzoquinones ( 1 ) with ethylenediamine and/or o‐phenyl‐enediamine in methylene chloride gives pyrazino[2,3‐g]quinoxalines derivative 6 and/or tetrapentacene derivative 7 respectively. The products 5‐aryl‐ and 6‐aryl‐1/H‐indazole‐4,7‐diones 8 and 9 were obtained in the 1,3‐dipolar cycloaddition of diazomethane to ( 1 ).     

Spiro[4H‐pyran‐3,3′‐oxindoles] Derived from 1,2,3,4‐tetrahydroquinoline—Part 2

Reaction of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij ]quinoline‐1,2‐dione ( 3 ) with two equivalents of cyclic 1,3‐dicarbonyl compounds under acid catalysis generates spiro[4H‐pyran‐3,3′‐oxindoles] 7 . In contrast, though base catalysis also achieves double addition, the final products 8 result from subsequent ring opening of the five‐membered lactam via intramolecular attack by enolate; these products can be converted into the spiro[4H‐pyran‐3,3′‐oxindoles] by treatment with acid.     

Spiro[pyrido[3,2,1‐ij]pyrimido[4,5‐b]quinoline‐7,5′‐pyrrolo[2,3‐d]pyrimidines] and Spiro[pyrimido[4,5‐b]quinoline‐5,1′‐pyrrolo[3,2,1‐ij]quinolines] Derived from 5,6‐Dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione

Reaction of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione ( 1 ) with two equivalents of some 6‐aminouracils (or 6‐amino‐2‐thiouracil) generates spirocyclic tetrahydrobenzo[if]quinolizines ( 7 ). The one‐pot, three‐component reaction of amido ketone ( 1 ) with 6‐aminouracil (or 6‐amino‐2‐thiouracil) and a cyclic six‐membered 1,3‐diketone produces spirocyclic tetrahydropyrrolo[3,2,1‐ij]quinolinones ( 15 ).     

Yb(OTf)3: An Efficient Catalyst for the Synthesis of 11‐Aryl‐7H‐cyclopenta[b][4,7]phenanthrolin‐10(11H)‐One Derivatives

A mild and efficient method for the synthesis of 8,9‐dihydro‐11‐aryl‐7H‐cyclopenta[b][4,7]phenanthrolin‐10(11H)‐one derivatives via three‐component reaction of aromatic aldehyde, quinolin‐6‐amine and cyclopentane‐1,3‐dione is described catalyzed by Yb(OTf)₃. The features of this procedure are mild reaction conditions, good to high yields, and operational simplicity.     

Synthesis and Anti‐influenza Virus Activity of Novel bis(4H‐chromene‐3‐carbonitrile) Derivatives

An efficient and convenient method for the synthesis of bis(4H‐chromene‐3‐carbonitrile) derivatives by one‐pot, multicomponent reaction of bis‐aldehydes, malononitrile, and dimedone in the presence of a catalytic amount of piperidine is reported. Bis(2‐benzylidene‐1H‐indene)‐1,3‐(2H )‐dione derivatives were obtained as the main products as a result of reaction of the bis(arylidenemalononitriles) with indandione. The anti‐influenza H5N1 virus activities of the newly prepared bis‐chromene derivatives are also investigated.     

New synthesis and reactivity of 3‐bromoacetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one with binucleophilic amines

3‐(Bromoacetyl)‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one was synthesized by the reaction of dehydroacetic acid (DHAA) with bromine in glacial acetic acid. Novel heterocyclic products were synthesized from the reaction of bromo‐DHAA with alkanediamines, phenylhydrazines, ortho‐phenylenediamines, and ortho‐aminobenzenethiol. The obtained new products 3‐(2‐N‐substituted‐acetyl)‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐ones, 4‐hydroxy‐3‐[1‐hydroxy‐2‐(2‐phenylhydrazinyl)vinyl]‐6‐methyl‐2H‐pyran‐2‐one, 1‐(2,4‐dinitrophenyl)‐7‐methyl‐2,3‐dihydro‐1H‐pyrano[4,3‐c]pyridazine‐4,5‐dione, 3‐(3,4‐dihydroquinoxalin‐2‐yl)‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one/3‐(3,4‐dihydroquinoxalin‐2‐yl)‐6‐methyl‐2H‐pyran‐2,4(3H)‐dione, 6‐methyl‐3‐(3,4‐dihydroquinoxalin‐2‐yl)‐2H‐pyran‐2,4(3H)‐dione, and (E)‐3‐(2H‐benzo[b][1,4]thiazin‐3(4H)‐ylidene)‐6‐methyl‐2H‐pyran‐2,4(3H)‐dione were fully characterized by IR, ¹H and ¹³C NMR, and mass spectra. J. Heterocyclic Chem., 2011.