MICROWAVE INDUCED DRY-MEDIA SYNTHESIS OF SPIRO[INDOLE-THIAZOLIDINONES/ THIAZINONES] AS POTENTIAL ANTIFUNGAL AND ANTITUBERCULAR AGENTS AND STUDY OF THEIR REACTIONS

A series of new spiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-diones (IV) and spiro[3H-indole-3,2′-tetrahydro-1,3-thiazine]-2,4′(1H)-diones (V) have been synthesized in 85–93% yield by the one-pot environmentally benign microwave induced technique involving the cyclocondensation of 3-arylimino-2H-indol-2-ones (III) with thioacids viz. mercapto aceticacid (a)/3-mercapto propionicacid (b) using montmorillonite KSF as inorganic solid support. Intermediates (III) were synthesized in situ by the reaction of indole-2,3-diones (I) and substituted anilines (II). The spiro compounds have been further subjected to solvent-free acetylation, aminoalkylation and thiation under microwave irradiation using solid supports. The synthesized compounds have been screened in vitro for antifungal activity against Rhizoctonia solani, Fusarium oxysporum, and Collectotrichum capsici, and antitubercular acivity against Mycobacterium tuberculosis.     

Studies in spiroheterocycles. Part XIII. Synthesis of a novel spiro system: Spiro[9H-acridine-9,3′-[3h]indol]-2′(1′H)-one and related compounds from new fluorinated spiro[3H-indole-3,9′-[9H]xanthen]-2(1H)-ones

A new spiroheterocyclic system spiro[9H-acridine-9,3′-[3H]indol]-2′(1′H)-one and related compounds have been prepared by the reaction of spiro[3H-indole-3,9′-[9H]xanthen]-2(1H)-ones with aromatic amine or ammonium acetate. The latter were prepared by heating fluorinated indole-2,3-diones with m-/p-cresols or α-naphthol in the presence of sulphuric acid at 230-240°. The synthesized compounds have been characterized on the basis of their elemental analyses, ir, nmr (1_H, 13_C, 19_F) and mass spectral data.     

Synthesis of spiro[2H-indole-2,1′-1H-isoindole]-3,3′-diones,spiro[1H-isobenzofuran-1,2′-2H-indole]-3,3′-diones and spiro[benzofuran-2,1′-isobenzofuran]-3,3′-diones via transannular reactions of eight membered ring intermediates

An auto oxidation-rearrangement product 4 was isolated from a high dilution reaction of ninhydrin with 3,4,5-trimethoxyaniline in water. A general synthesis of this compound and its derivatives 4–6 was devised by oxidation of tetrahydroindeno[1,2-b]indol-10-ones 1–3 with sodium periodate to give isoindolo[2,1-a]-indole-6,11-diones 4–6 in good yield. Compounds 4–6 can be easily transformed into spiro[1H-isobenzofuran-1,2′-2H-indole]-3,3′-diones 8–10 , spiro[2H-indole-2,1′-1H-isoindole]-3,3′-diones 11–13 and isoindole[1,2-a:2′,1′-b]pyrimidine-5,15-diones 15, 16 in high yields. Analogous reactions were performed on 3-amino-5a, 10a-dihydroxybenzo[b]indeno[2,1-d]furan-10-one ( 17 ) to give a dibenzoxocintrione 18 , spiro-[benzofuran-2,1′-isobenzofuran]-3,3′-dione 19 and an isoindol-1-one 20 .     

Spiro[1,3-benzoxathiepin-4(5H),1′-cyclohexa[2,4]diene]-2,2′-dione,a Novel Heterocyclic Ring System

The 4,4′,6,6′-tetrasubstituted 2,2′-alkylidenebis(phenols) 1 reacted with CISCOI to give spiro[1,3-benzoxathiepin-4(5H), 1′-cyclohexa[2,4]diene]-2,2′-diones 4 , together with cyclic carbonates 5 . The structures of the products were elucidated mainly by ¹³C-NMR and ¹H-NMR spectroscopy.     

Synthesis of 1,3‐thiazole and 1,2,4‐oxadiazole substituted spiro[3H‐indole‐3,2′‐thiazolidine]‐2,4′(1H)‐diones

Some new derivatives of spiro[3H‐indole‐3,2′‐thiazolidine]‐2,4′(1H)‐dione with the heterocyclic ring such as substituted thiazole and 1,2,4‐oxadiazole attached to the indolinone ring via CH₂ linkage has been synthesized in moderate yields. The synthesis have been carried out by making use of the reactivity of the NH group of the indolinone moiety present in spiro[3H‐indole‐3,2′‐thiazolidine]‐2,4′(1H)‐dione.     

Novel regioselective synthesis of 3′H,4H‐spiro[chromene‐3,2′‐[1,3,4]thiadiazol]‐4‐one containing compounds

A variety of 3″,5″‐diaryl‐3″H,4′H‐dispiro[cyclohexane‐1,2′‐chromene‐3′,2″‐[1,3,4]thiadiazol]‐4′‐ones 3a‐c were synthesized regioselectively through the reaction of 4′H,5H‐trispiro[cyclohexane‐1,2′‐chromene‐3′,2″‐[1,3,4]oxadithiino[5,6‐c]chromene‐5″,1″′‐cyclohexan]‐4′‐one ( 1 ) with nitrilimines (generated in situ via triethylamine dehydrohalogenation of the corresponding hydrazonoyl chlorides 2a‐c ) in refluxing dry toluene. Single crystal X‐ray diffraction studies of 3a,b add support for the established structure. Similarly, 3′,5′‐diaryl‐2,2‐dimethyl‐3′H,4H‐spiro[chromene‐3,2′‐[1,3,4]thiadiazol]‐4‐ones 5a‐c were obtained in a regioselective manner through the reaction of 2,2,5′,5′‐tetramethyl‐4H,5′H‐spiro[chromene‐3,2′‐[1,3,4]oxadithiino[5,6‐c]chromen]‐4‐one ( 4a ) with nitrilimines under similar reaction conditions. On the other hand, reaction of 2,5′‐diethyl‐2,5′‐dimethyl‐4H,5′H‐spiro[chromene‐3,2′‐[1,3,4]oxadithiino‐[5,6‐c]chromen]‐4‐one ( 4b ) with nitrilimines in refluxing dry toluene afforded the corresponding 3′,5′‐diaryl‐2‐ethyl‐2‐methyl‐3′H,4H‐spiro[chromene‐3,2′‐[1,3,4]thiadiazol]‐4‐ones 5d‐f as two unisolable diastereoisomeric forms.     

Novel Fluorinated Spiro [Indole-indazolyl-thiazolidine]-2,4′-diones: Design and Synthesis

The reaction of indol-2,3-diones ( 1a–i ) with 5-aminoindazole ( 2 ) has resulted in the formation of hitherto unknown 3-(indazol-5-yl)iminoindol-2-ones ( 3a–i ) in quantitative yields which, on 1,3-dipolar cyclocondensation with mercaptoacetic acid ( 4 ), has afforded a series of new spiro heterocycles, 3′-(indazol-5-yl) spiro[3H, indol-3, 2′ -thiazolidine]-2,4′-diones* ( 5a–i ).     

Potential anticonvulsants. VII. Synthesis of 5′-methylspiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-diones

The title compounds have been prepared, by the cyclocondensation of thiolactic acid with isatin-3-imines. 5′-Methyl-3′-phenyl-spiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-dione has been subjected to the Mannich condensation to give 1-substituted derivatives. With one exception, all of the products were inactive in an anticonvulsant screen.     

Synthesis of spiro[furan-3,3′-indolin]-2′-ones by PET-catalyzed [3+2] reactions of spiro[indoline-3,2′-oxiran]-2-ones with electron-rich olefins

An efficient procedure for the synthesis of spiro[furan-3,3′-indolin]-2-ones and dispiro[cycloalkane-1,2′-furan-3′,3″-indolin]-2″-ones has been achieved in high yields and stereoselectivity by photoinduced electron transfer-catalyzed [3+2] reactions of substituted spiro[indoline-3,2′-oxiran]-2-ones with olefins. The reactions proceed by ring opening of spiro[indoline-3,2′-oxiran]-2-ones via C_β–O bond cleavage and subsequent cycloaddition with olefins by using 2,4,6-triphenylpyrylium tetarfluoroborate (TPT) as a sensitizer.     

Selective Synthesis Dispiro[indoline‐3,2′‐pyrrolidine‐3′,3″‐quinoline] Derivatives and Spiro[imidazole‐4,3′‐quinoline] Derivatives via 1,3‐Dipolar Cycloaddition Reaction

A new class of spiro compounds as dispiro[indoline‐3,2′‐pyrrolidine‐3′,3″‐quinoline] and spiro[imidazole‐4,3′‐quinoline] have been developed from quinolone derivative adopting modern synthetic methodologies.     

Synthesis of 5′-halo-2′,3′-lyxo-epoxy and 2′,3′-unsaturated thieno[3,2-d]pyrimidine nucleosides

A series of thieno[3,2-d]pyrimidine-2,4-dione nucleosides modified in the carbohydrate moiety has been synthesized. In the first part, synthetic routes are described for the replacement of 5′-hydroxyl group in preformed 1-(β-D-ribofuranosyl)thieno[3,2-d]pyrimidine-2,4-dione I by fluoro, iodo or chloro atoms. Reduction of the 5′-iodo substituent of VI was then carried out catalytically using palladium on carbon as catalyst to give the expected 5′-deoxy derivative VIII. The lyxo-epoxide derivative XII was then synthesized by sequential treatment of the 5′-deoxy-5′-chloro derivative X with methanesulfonyl chloride and with sodium hydroxide. In the second part, most of attention has been devoted to apply different methods reported in the literature that allow access to 2′,3′-olefinic derivatives from the corresponding 2′,3′-dihydroxy precursor. The 5′-O-silyl protected bisxanthate XIV either on reduction with tri-n-butyltin hydride or by reductive elimination of the haloacetate XVI afforded the free 2′,3′-olefin nucleoside after removal of the 5′-protecting group. However none of the compounds in this series exhibited significant antiviral activity against HIV at the doses tested.     

Three‐Component Reaction for Construction of Spiro[indoline‐3,7′‐thiazolo[3,2‐a]pyridines] and Spiro[benzo[4,5]thiazolo[3,2‐a]pyridine‐3,3′‐indolines]

The three‐component reaction of thiazole (benzothiazole), dialkyl but‐2‐ynedioate, and isatinylidene malononitriles in toluene at 110–120°C in a sealed tube afforded a mixture of cis/trans‐isomers of functionalized diastereoisomeric spiro[indoline‐3,7′‐thiazolo[3,2‐a]pyridines] and spiro[benzo[4,5]thiazolo[3,2‐a]pyridine‐3,3′‐indolines] in good yields. Both cis‐isomers and trans‐isomers were successfully separated out and fully characterized with spectroscopy and single crystal determination. Under similar conditions, the three‐component reaction containing 2‐(1,3‐dioxo‐1H‐inden‐2(3H)‐ylidene)malononitrile resulted in spiro[indene‐2,7′‐thiazolo[3,2‐a]pyridine] derivatives.     

Synthesis of 2‐Coumarinyl and Spiroindolyl‐5‐Phenyl‐1,3,4‐Oxadiazoles

The 2H‐1‐benzo/naphthopyran‐2‐one‐4‐yl (un)substituted phenyl‐1,3,4‐oxadiazoles has been synthesized by the oxidative cyclization of benzoic acid hydrazides formed in situ by the condensation of the respective 2H‐1‐benzo/naphthopyran‐2‐one‐4‐carboxaldehyde and (un)substituted monobenzoyl hydrazide in moderate yields. Also, spiro[indoline‐thiozolidine]‐2,4′‐diones has been syhthesized in a similar way from 3‐phenyl‐spiro[3H‐indoline‐3,2′‐thiozolidine]‐2,4′‐(1 H)dione monohydrazide and (un)substituted benzaldehydes.     

A convenient synthesis for some new pyrido[3′,2′:4,5]thieno-[3,2-d]pyrimidine derivatives with potential biological activity

Ready, convenient synthesis for 8-cyano-7-ethoxy-4-oxo-9-phenyl-2-substituted-1,2,3,-4-tetrahydropyrido-[3′,2′:,4,5]thieno[3,2-d]pyrimidines 5 , 8-cyano-7-ethoxy-4-oxo-9-phenyl-2-substituted-3,4-dihydropyrido[3′,2-: 4,5]thieno[3,2-d]pyrimidines 6 , 4-chloro-8-cyano-7-ethoxy-9-phenyl-2-substitutedpyrido[3′,2′:4,5]thieno[3,2-4 -pyrimidines 7 and 8-cyano-7-ethoxy-2-(2′-nitrophenyl)-9-phenyl-4-substitutedpyrido[3′,2′:4,5]thieno[3,2- d ]pyrimidines 8-18 from 2-chloro-3,5-dicyano-6-ethoxy-4-phenylpyridine 1 via 3,5-dicyano-6-ethoxy-2-mercapto-4-phenylpyridine 2 and aminocarboxamide 4 are reported. In addition, the reaction of hydrazino derivative 12 with reagents such as formic acid and triethyl orthoformate yielded the fused tetraheterocyclic 8-cyano-9- ethoxy-5-(2′-nitrophenyl)- 7-phenylpyrido[3′,2′:4,5]thieno[2,3-e]-1, 2,4-triazolo[4,3-c]pyrimidine system 19 .     

One‐pot Multicomponent Synthesis of Isoxazolyl Spiro[indoline‐3,2′‐pyrrolidine]‐2,4′‐diones Catalyzed by CAN

An efficient CAN‐catalyzed synthesis of isoxazolyl spiro[indoline‐3,2′‐pyrrolidine]‐2,4′‐diones has been developed via one‐pot three‐component reaction of isoxazole amine, differently substituted isatins, and acetone at room temperature. Several catalysts and solvents have been screened for the efficiency, but the optimum results were obtained with CAN in THF.     

Cu(II)-β-cyclodextrin-catalyzed synthesis of spiro[indoline-3,4′-pyrano[3,2-c]chromene]-3′-carbonitrile derivatives

Cu(II)-β-cyclodextrin-catalyzed synthesis of spiro[indoline-3,4′-pyrano[3,2-c]chromene]-3′-carbonitriles through the reaction of isatin derivatives, 4-hydroxycoumarin, and malononitrile in ethanol at room temperature.     

N,N,N′,N′‐Tetrabromobenzene‐1,3‐disulfonamide Catalyzed Synthesis of New Spiro[chroman‐3,2′‐chromeno[2,3‐b]furan]‐2,4,4′‐(3′H)‐trione Derivatives

An efficient approach for one‐pot synthesis of biologically active new spiro[chroman‐3,2′‐chromeno[2,3‐b ]furan]‐2,4,4′‐(3′H )‐trione derivatives from tandem Knoevenagel–Michel addition–heterocyclization reaction between 4‐hydroxycumarin and various aldehydes in the presence of N,N,N ′,N ′‐tetrabromobenzene‐1,3‐disulfonamide as an efficient catalyst at ambient temperature under solvent‐free conditions was reported. Simple procedure, high yields, easy work‐up, and reusability of the catalyst are the significant advantages of this process.     

Synthese und Konfiguration einiger Spiro [indan-2,2′-pyrrolidin]- und Spiro [pyrrolidin-2,2′-tetralin]-Derivate,

Synthesis and configuration of some spiro [indan-2,2′-pyrrolidine] and spiro [pyrrolidine-2,2′-tetraline] derivatives Catalytic hydrogenation of the nitrosoindan and nitrosotetralin derivatives 8 yielded trans-1-hydroxy-spiro [indan-2,2′-pyrrolidin]-5′-one ( 9 ) and trans-1′-hydroxy-spiro [pyrrolidine-2,2′-tetralin]-5-one ( 10 ) respectively, whilst the corresponding cis compounds 12 and 15 were prepared via the chlorides 11 and 14 . The configurations of 10 and 13 were determined by X-Ray analysis.     

Facile synthesis of novel spiro[azetidine-2,4′(1′H)-isoquinoline-1′,3′,4(2′H)-triones]

A convenient general method for the synthesis of a new heterocycle, spiro[azetidine-2,4′(1′H)-iso-quinoline-1′,3′,4(2′H)-trione] is described. The key intermediate 2 was prepared by direct halogenation of position-4 of acid 3 with thionyl chloride, and subsequent treatment of the generated 4-Cl, 4-acetyl chloride 11 with a THF/NH₃ solution at low temperature.     

SYNTHESIS AND REACTIONS OF 2,3-DIHYDRO- 5-ARYL-5H,6H-THIAZOLO[3,2-b]-2,4-DIAZAFLUORENE-3,6-DIONES OF POTENTIAL BIOLOGICAL ACTIVITIES

Abstract

1,2,3,4-Tetrahydro-l-aryl-3,9-dioxo-2,4-diazafluorenes (2) and 1,2,3,4-tetrahydro-1-aryl-9-oxo-3-thi-oxo-2,4-diazafluorenes (3) were newly synthesized. Compounds 3 reacted with chloroacetic acid, α-bromopropanoic acid, or B-bromopropanoic acid in the presence of fused sodium acetate and acetic anhydride to give 2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (4), 2-methyl-2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (5) and 2,3-dihydro-6-aryl-6H,7H-thiazino[3,2-b]2,4-diazafluorene-4,7-diones (6), respectively.

2,3-Dihydro-2-arylmethylene-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (7) were prepared by the reaction of compounds (3) with chloroacetic acid and aromatic aldehydes in the presence of fused sodium acetate and acetic anhydride or by the reactions of (4) with aromatic aldehydes in the presence of acetic anhydride.

2-(Arylhydroazono)-5-aryl-2,3-dihydro-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (8) were synthesized by coupling (4) with aryldiazonium salts in the presence of pyridine.