Investigation of the reactions of fluorine containing 3-hydrazino-5H-1, 2, 4-triazino[5, 6-b]indoles with ethyl acetoacetate. Synthesis of some novel tetracyclic ring systems

Novel tetracyclic ring systems viz. 3-methyl-1-oxo-12H-1, 2, 4-triazepino[3′,4′:3, 4][1, 2, 4]triazino[5, 6-b]indole ( 4a ) and 3-methyl-5-oxo-12H-1, 2, 4-triazepino[4′,3′:2, 3][1, 2, 4]triazino[5, 6-b]indole ( 5a ), having angular and linear structures respectively, were synthesized by the cyclization of 3-oxobutanoic acid [5H-1, 2, 4-triazino-[5, 6-b]indole-3-yl]hydrazone ( 3a ). However, cyclization of 3b (R = CH_a, R¹ = R² = H) afforded the angular product 4b exclusively. Moreover, cyclization of 3c (R = R³ = H, R¹ = F) yielded 7-fluoro-1-0xo-10H-1, 3-imidazo[2′,3′:3, 4][1, 2, 4]triazino[5, 6-b]indole ( 6c ) and 7-fluoro-3-oxo-10H-1, 3-imidazo[3′,2′:2, 3][1, 2, 4]triazino-[5, 6-b]indole ( 7c ) instead of the expected triazepinone derivatives. Compound 3d (R = R¹ = H, R² = CF₃) also gave an imidazole derivative but only one angular product was obtained. In all these reactions, formation of the angular product involving cyclization at N-4 is favoured. Characterization of these products have been done by elemental analyses, ir, pmr, ¹⁹F nmr and mass spectral studies.     

Synthesis of 1,2-diazepino[3,4-b]quinoxalines and pyrido[3′,4′:9,8][1,5,6]oxadiazonino[3,4-b]quinoxalines via a 1,3-dipolar cycloaddition reaction

The reaction of 6-chloro-2-(1-methylhydrazino)quinoxaline 4-oxide 8 with furfural, 3-methyl-2-thiophene-carbaldehyde, 2-pyrrolecarbaldehyde, 4-pyridinecarbaldehyde and pyridoxal hydrochloride gave 6-chloro-2-[2-(2-furylmethylene)-1-methylhydrazino]quinoxaline 4-oxide 5a , 6-chloro-2-[1-methyl-2-(3-methyl-2-thienyl-methylene)hydrazino]quinoxaline 4-oxide 5b , 6-chloro-2-[1-methyl-2-(2-pyrrolylmethylene)hydrazino]quinoxa-line 4-oxide 5c , 6-chloro-2-[1-methyl-2-(4-pyridylmethylene)hydrazino]quinoxaline 4-oxide 5d and 6-chloro-2-[2-(3-hydroxy-5-hydroxymethyl-2-methyl-4-pyridylmethylene)-1-methylhydrazino]quinoxalme 4-oxide 5e , respectively. The reaction of compound 5a or 5b with 2-chloroacrylonitrile afforded 8-chloro-3-(2-furyl)-4-hydroxy-1-methyl-2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxaline-5-carbonitrile 6a or 8-chloro-4-hydroxy-1-methyl-3-(3-methyl-2-thienyl)-2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxaline-5-carbonitrile 6b , respectively, while the reaction of compound 5e with 2-chloroacrylonitrile furnished 11-chloro-7,13-dihydro-4-hydroxy-methyl-5,14-methano-1,7-dimethyl-16-oxopyrido[3′,4′:9,8][1,5,6]oxadiazonino[3,4-b]quinoxaline 7.     

Synthesis of 4H-1,3,4-oxadiazino[5,6-b]quinoxalines from 2-substituted quinoxaline 4-oxides

The reaction of 6-chloro-2-(1-methylhydrazino)quinoxaline 4-oxide 8 with acetic anhydride resulted in the intramolecular cyclization to give 8-chloro-2,4-dimethyl-4H-1,3,4-oxadiazino[5,6-b]quinoxaline 7a , while the reaction of compound 8 with acetic anhydride/pyridine or acetic anhydride/acetic acid afforded 3-(2,2-diacetyl-1-memymydrazmo)-7-chloro-2-oxo-1,2-dihydroquinoxaline 9 , effecting no intramolecular cyclization. The reaction of 2-(2-acetyl-1-methylhydrazino)-6-chloroquinoxaline 4-oxide 10a or 6-chloro-2-(1-methyl-2-trifluoroacetylhydrazino)quinoxaline 4-oxide 10b with phosphoryl chloride provided compound 7a or 8-chloro-4-memyl-2-trifluoromethyl-4H-1,3,4-oxadiazino[5,6-b]quinoxaline 7b , respectively. The reaction of compound 7b with phosphorus pentasulfide gave 7-chloro-3-(1-methyl-2-trifluoroacetylhydrazino)-2-thioxo-1,2-dihydroquinoxaline 11 , whose dehydration with sulfuric acid in acetic acid afforded 8-chloro-4-methyl-2-trifluoromemyl-4H-1,3,4-thiadiazino[5,6-b]quinoxaline 12 .     

The Synthesis of Octahydro-7-phenylpyrazino[2,1-b][3]benzazepines

Octahydro-7-phenylpyrazino[2,1-b][3]benzazepine ( 1a ) was prepared from 1-methyl-3-phenylmethylpiperazine 5a by reaction with styrene oxide followed by sulfuric acid cyclization of the resulting alcohol 6a . The diastereomeric mixture 1a was further separated into the diastereomers 1a′ and 1a″ . Similarly 1-methyl-3-(3-chloro-4-methoxyphenyl)piperazine was reacted with styrene oxide to yield 6c which on cyclization with 1.5 equivalents of sulfuric acid in trifluoroacetic acid gave a 3:7 mixture of phenolic, 1d , and methoxy, 1c , octa-hydropyrazino[2,1-b][3]benzazepines. The reaction of the 2,5-piperazinedione 4c with sodium acetoxyborohydride gave a 49% yield of the 2-piperazinone 7 which was similarly carried on to the corresponding 1(2H)-oxohexahydropyrazino[2,1-b][3]benzazepine 9 .     

Reaction of 4,5-diaminopyrimidine and ethyl acetoacetate: Synthesis and chemistry of isomeric dihydropyrimido[4,5-b][1,4] diazepinones

Depending upon reaction conditions, 4,5-diaminopyrimidine and acetoacetic ester gave a variety of condensation products, including the two isomeric dihydropyrimido[4,5-b][1,4]-diazepinones. Under conditions leading to bicyclic products, the formation of 1,5-dihydro-4-methyl-2H-pyrimido[4,5-b][1,4]diazepin-2-one ( 2 ) was strongly favored. The isomeric 3,5-dihydro-2-methyl-4H-4-one compound ( 4 ) was best obtained by cyclization of ethyl 3-(4-amino-5-pyrimidylamino)crotonate ( 3 ) under base catalysis. Thermal rearrangement of 2 and 4 proceeded, in each instance, with loss of the isopropenyl moiety and gave 8-purinone. Compound 4 underwent ring contraction under the influence of alkoxide to yield a product which was shown to be the 7-isopropenyl-8-purinone ( 6 ).     

The synthesis of 5,6-dihydro-6-methylthiazolo-[2,3-b] [1,3] benzodiazepines, 2,3,10,11-tetrahydro-10-methyl-1H-cyclopenta[4,5] thiazolo[2,3-b] [1,3] benzodiazepine,and 7,8,9,10,12,13-hexahydro-13-methylbenzothiazolo[2,3-b] [1,3]-benzodiazepine via 1,3,4,5-tetrahydro-5-methyl-2H-1,3-benzodiazepine-2-thione

Catalytic reductive scission of 4-methylcinnoline (V) with Raney nickel afforded o-amino-β-methylphenethylamine (IV) in 57% yield. Treatment of IV with carbon disulfide followed by thermal cyclization of the product furnished 1,3,4,5-tetrahydro-5-methyl-2H-1,3-benzodiazepine-2-thione (III). Reaction of III with ethyl chloroacetate, ethyl 2-bromohexanoate, ethyl 2-chloroacetoacetate, 2-bromo-2′-methoxyacetophenone, and 2-bromoacetophenone provided a series of substituted 5,6-dihydro-6-methylthiazolo[2,3-b][1,3]benzodiazepines. Condensation of III with 2-chlorocyclopentanone and 2-chlorocyclohexanone gave 2,3,10,11-tetrahydro-10-methyl-1H-cyclopenta[4,5]thiazolo[2,3-b][1,3]benzodiazepine and 7,8,9,10,12,13-hexahydro-13-methylbenzothiazolo[2,3-b][1,3]benzodiazepine, respectively. Structure assignments are discussed. None of the compounds possessed appreciable biological activity.     

A new method for the synthesis of 4H-1,3,4-thiadiazino[5,6-b]quinoxalines

The reaction of 6-chloro-2-[1-methyl-2-(Mmemylthiocarbamoyl)hydrazino]quinoxaline 4-oxide 5 with acetic anhydride or trifluoroacetic anhydride resulted in dehydrative cyclization to give 2-(N-acetyl)-memylamino-8-chloro-4-methyl-4H-1,3,4-thiadiazino[5,6-b]quinoxaline 6 or 8-chloro-2-(N-trifluoroacetyl)methylamino-4-methyl-4H-1,3,4-thiadiazino[5,6-b]quinoxaline 9 , respectively. The oxidation of compound 6 or 9 with 2-fold molar amount of m-chloroperbenzoic acid afforded the 4H-1,3,4-thiadiazino-[5,6-b]quinoxaline 1,1-dioxide 8 or 13 , respectively. The acetyl group of compound 6 was hardly hydrolyzed, but the trifluoroacetyl group of compound 9 was easily hydrolyzed to change into 8-chloro-4-methyl-2-memylamino-4H-1,3,4-thiadiazino[5,6-b]quinoxaline 10 . The acylation of compound 10 with acetic anhydride, trifluoroacetic anhydride, phenyl isocyanate, and chloroacetyl chloride furnished the 2-(N-acetyl)methylamino 6 , 2-(N-trifluoroacetyl)methylamino 9 , 2-(1-methyl-3-phenylureido) 11 , and 2-(N-chloroacetyl)methylamino 12 derivatives, respectively.     

New Furano-sesquiterpenoids from Mediterranean Sponges

A mixture of sponges of the East Pyrenean Mediterranean is shown to contain the known sponge products longifolin ( 1 ), avarol ((+)- 3 ), and avarone ( 4 ) and the terrestrial-plant product sesquirosefuran ( 2 ), besides to the new furano-sesquiterpenoids tavacfuran (= 3-methyl-2-[(3′Z)-3′-methyl-4″-methyl-2″-furyl-3′-butenyl]furan; ( 5 ) and tavacpallescensin (= 5,10-dihydro-6,9-dimethyl-4H-benzo[5,6]cyclohepta[1,2-b]furan; 6 ) and the new furano-butenolide sesquiterpenoids tavacbutenolide-1 (= (±-4-ethoxy-2-methyl-4-)[(2′E)-2′-methyl-4′-(3″-methyl-2″-furyl)-2′-butenyl]-2-buten-4-olide; (±)- 7 ) and tavacbutenolide-2 (= (±)-4-ethoxy-3-methyl-4-[2′E)-3′-methyl-4′-(4″-methyl-2″-furyl)-2′-butenyl]-2-buten-4-olide; (±)- 8 ). Structural assignments are based on NMR data and on the synthesis of the (E)-isomer of 5 . The sponge Dysidea tupha of the same area is also shown to contain the two sesquiterpenoids ent-furodysinin ((?)- 14 ), which is enantiomeric to a product of a Dysidea sp. of Australian waters, and tuphabutenolide ((+)- 15 ).     

The syntheses of 4b,5a-dihydrodibenz[3,4:5,6]anthra[1,2-b]oxirene and 4b,5a-dihydro-5H-dibenz[3,4:5,6]anthra[1,2-b]azirine

The syntheses of the K-oxide and K-imine derivatives of dibenz[a,j]anthracene ( 1 ) are described. The parent hydrocarbon 1 that was obtained as a side product in the Elbs pyrolysis of (2-methyl-1-naphthyl)-1′-naphthylmethanone ( 10 ) was oxidized to 3-(2-formylphenyl)-3-phenanthrenecarboxaldehyde ( 3 ). Treatment of the dialdehyde with tris(dimethylamino)phosphine gave 4b,5a-dihydrodibenz[3,4:5,6]anthra[1,2-b]oxirene ( 4 ). Reaction of the oxirane with sodium azide followed by triethyl phosphite cyclization of the mixture of trans azido-alcohols so formed, yielded mainly 4b,5a-dihydrodibenz[3,4:5,6]anthra[1,2-b]azirine ( 5 ).     

New tetracyclic compounds containing the β-carboline moiety

Oxidation of 1-methyl-3-methoxycarbonyl-β-carboline with selenium dioxide gave 1-formyl-3-methoxycarbonyl-β-carboline II . Compound II reacted with acetic or propionic anhydride to give easily the 2-methoxycarbonyl-6H-indolo[3,2,1-d,e][1,5]naphthyridin-6-ones III ; reaction of II with some primary amines led to the formation of the Schiff bases IV , which were reduced to the 1-aminomethyl-3-methoxycarbonyl-β-carbolines V with sodium borohydride. Cyclization of V with aqueous formaldehyde led to the pyrimido[3,4,5-lm]pyrido[3,4-b]indoles VI . Analogously, cyclization with formaldehyde, acetone or 1,1′-carbonyldiimidazole of the 3-aminomethyl- 1,2,3,4-tetrahydro-β-carbolines VIII , obtained by reaction of 3-methoxycarbonyl-1,2,3,4-tetrahydro-β-carboline VII with amines followed by lithium aluminium hydride reduction of the resulting amides, gave the imidazo[1′,5′-1,6]pyrido[3,4-b]indoles IX and X . Dieckmann cyclization of 3-methoxycarbonyl-2-[(3-ethoxycarbonyl)-1-propyl]-1,2,3,4-tetrahydro-β-carboline XI led to a 1:1 mixture of the β-ketoesters XII and XIII , which underwent deethoxycarbonylation to 5,6,8,9,10,11,11a,12-octahydroindolo[3,2-b]quinolizin-11-one XIV . Finally, the polyphosphoric acid (or esters) catalyzed cyclization of the N-acyl derivatives XVI of 3-hydrazinocarbonyl-β-carboline XV led smoothly to the 3-(1,3,4-oxadiazol-2-yl)-β-carbolines XVII .     

Synthesis of a rotenone-like benzopyranobenzopyranone

The synthesis of a novel rotenone-like molecule, 9-methoxy-8-methyl-6,6a,12,12a-tetrahydro[1]benzopyrano-[3,4-b][1]benzopyran-12-one ( 2 ) is described. Efficient syntheses of 3,4-dihydro-2H-[1]benzopyran-3-one ( 9 ) from ethyl 3-hydroxy-2H-[1]benzopyran-4-carboxylate ( 6 ), an intermediate in the synthesis of 2 , were developed. Thermolysis of 6 and 9 in decalin yielded 6,8-dihydro-14H-bis[1]benzopyrano[3,4-b:4′,3′-e]pyran-14-one ( 8 ), which has previously been described. Also produced in the thermolysis was the isomeric 1H-bis[1]-benzopyrano[3,4-b:3′,4′-á]pyran-7-(9H)one ( 10 ), the first member of a novel, pentacyclic ring system.     

The photochemical synthesis of novel heterocyclic compounds from s-triazolo[4,3-b]pyridazine (II)

s-Triazolo[4,3-b Jpyridazine (I) photochemically reacted with dihydropyran; 2,3-dihydro-p-dioxin; 2,5-dihydrofuran; 2,5-dimethoxy-2,5-dihydrofuran; and 1,3-dioxep-5-ene to give a new series of substituted pyrrolo[1,2-b]-.s-triazoles (II-IX). In most reactions, two or more products were formed. The following compounds have been prepared from I: 9-methylene-4a,5,6,7,8a,9-hexahydropyrano[2,3 :4,5]pyrrolo[1,2-b]-s-triazole (Ha), the corresponding 9-cyanomethyl product (III), and 9-methylene-4a,7,8,8a-tetrahydro-6H,9H-pyrano[3′,2′:4,5]pyrrolo[1,2-b]-s-triazole (IIb) from dihydropyran; 9-methylene-4a,6,7,8a-tetrahydro-9H-p-dioxino[2′,3′:4,5]-pyrrolo[1,2-6]-s-triazole (IV) from 2,3-dihydro-p-dioxin; 8-methylene-4a,5,7a,8-tetrahydro-7H-furo[3′,4′:4,5]pyrrolo[1,2-b]-s-triazole (V) and the corresponding 8-cyanomethyl product (VI) from 2,5-dihydrofuran; 8-cyanomethyl-5,7-dimethoxy-4a,5,7a,8-tetrahydro-7H-furo[3′,4′:4,5]-pyrrolo[1,2-6]-s-lriazole (VII) from 2,5-dimethoxy-2,5-dihydrofuran; and 10-methylene-4a,5,9a,10-tetrahydro-9H-[1,3]dioxepino[5′,6′:4,5]pyrrolo[1,2-b]-s-triazole (VIII) and the corresponding 10-cyanomethyl product (IX) from 1,3-dioxep-5-ene. The addition of several other compounds (1,2,3,6-tetrahydropyridine, 1-acetylimidazole, 3-sulfolene, 2,3-dihydro-p-dithiin, and vinylene carbonate) was attempted, but no reactions were observed.     

A Convenient Synthetic Approach to Newly Condensed Pyrazoloazines Based on Pyrazolo[3,4-b]pyridine

The reaction of 6-amino-5-cyano-3-methyl-1H-1-phenylpyrazolo[3,4-b]pyridine ( 2 ) and 6,7-dihydro-3-methyl-6-oxo-1H-1-phenylpyrazolo[3,4-b)]pyridine-5-carbonitrile ( 3 ) and 5-amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]-1H-pyrazolo[4′,3′-e]pyridine ( 12 ) with different reagents have been conducted to give newly condensed pyrazoloazines.     

The photochemical synthesis of novel heterocyclic compounds from s-triazolo [4,3-b] pyridazine,III

s-Triazolo[4,3-b]pyridazine (I) reacted photochemieally with bieyélo[2.2.1] hepla-2,5-diene, 1,5-cyclooctadiene, 1,3-cyclooctadiene, methylene cyclohexane, diethyl cis-1,2,3,6-tetrahydro-phthalate and ethyl 2-cyclopentene-1-acetate to givt: the following products: the endo and exo isomers of 4a, 5, 8a, 9-tetrahydro-9-rnethylene-5,8-rnethano-8H-s-triuzolo[1, 5-a]indole (II) and the endo and exo-9-cyanometliyl products (III and IV) from bicyclo[2.2.1] hepta-2,5-diene; 4a,5,-9, 10, 10a, 11-huxahydro-11-methylene-6H-cycloocta[4,5]pyrrolo[1,2-b]-s-triazole (V) and the 11-cyanomethyl product VI from 1,5-cyclooctadiene: 4a,7,8,9,10,10a-hexahydro-11 -inethylene-11H-cycloocta[4,5]pyrrolo[1,2-b]-s-triazole(VII),4a, 5, 7, 8, 10a, 11-hexahydro-11-methylene-6H-cycloocta[4,5]pyrroIo[1,2-b]-s-triazole (VIII) and their respective 9-cyanomethyl products (X and 1X) from 1,3-cyclooctadiene; 6′, 7′ -dihydro-7′ -methylenespiro[cyclohexane-1, 5′-[5H] pyr-rolo[1,2-b]-s-triazole] (XI), 6′, 7′-dihydro-7′-meth) lene. spiro cyclohexane-1, 6′-[5H]pyrrolo[1,2-b]-s-triazole] (XII) and their respective 7 -eyanomethyl products (XIII and XIV) from melhylene cyclohexane; 6,7-dicarbethoxy-9-cyanomelhyl-4a, 5, 7, 8, 8a, 9-hexahydro-6H-s-triazolo[1,5-a]indole (XV) from diethyl cis-1, 2, 3, 6-tetrahydrophlhalate: and 5-earl)elhoxymethyl-8-eyanomethyl-4a, 5, 6, 7, 7a, 8-hexahydrocyclopenta[4,5]pyrrolo( 1, 2-b]-s-triazole (XVI) from ethyl 2, 2-cyclo-pentene-1-acetate. Many other alkenes, particularly the phenyl ethylenes, did not react with compound 1. In general, more than one product was isolated for each reaction except in the case of the two ester alkenes where a single eyanomethyl product was observed.     

About the synthesis of [1,2]diazepinoindole derivatives from ethyl 2-(1-methylindole)acetate, 2-indole and 3-indoleacetohydrazones

The Vilsmeier-Haack reaction with ethyl 2-(1-methylindole)acetate and N,N-Dimethylamides/phosphorus oxychloride gave (65–85%) of ethyl 2-(3-acyl-1-methylindole)acetates 2 , which when boiled with hydrazine yielded about 90% of 4,5-dihydro-6-methyl-4-oxo-3H[1,2]diazepino[5,6-b]indoles 3. The attempted cyclization of 2-(1-methylindole)acetohydrazones 6 with acyl (acetyl and benzoyl) chlorides/triethylamine, to [1,2]diazepino[5,6-b]indole derivatives was fruitless and the bis(acyl)hydrazones 9 were obtained. Several transformations of 9 are reported. Similarly, the attempted cyclization of 3-indoleacetohydrazones 14 with acetyl chloride/triethylamine to [1,2]diazepino[4,5-b]indole derivatives was also fruitless and the bis(acyl)hydrazones 16 were again obtained.     

Studies on the synthesis of heterocyclic compounds. Part IV. Further investigation of the pschorr reaction with some pyrazole derivatives

Thermal decomposition of the diazonium sulfate derived from N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-aminobenzamide afforded products formulated as 1-phenyl-3-methyl[2]benzopyrano[4,3-c]pyrazol-5-one (yield 10%), 1,4-dimethyl-3-phenylpyrazolo[3,4-c]isoquinolin-5-one (yield 10%), N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-hydroxybenzamide (yield 8%) and 4′-hydroxy-2,3′-dimethyl-1′-phenylspiro[isoindoline-1,5′-[2]-pyrazolin]-3-one (yield 20%). Decomposition of the diazonium sulfate derived from N-methyl-(1,3-diphenylpyrazol-5-yl)-2-aminobenzamide gave products formulated as 7,9-dimethyldibenzo[e,g]pyrazolo[1,5-a][1,3]-diazocin-10-(9H)one (yield 8%), 4-methyl-1,3-diphenylpyrazolo[3,4-c]isoquinolin-5-one (yield 7%) and 4′-hydroxy-2-methyl-1′,3′-diphenylspiro[isoindoline-1,5′-[2]pyrazolin]3-one (yield 10%). The spiro compounds 6a,b underwent thermal and acid-catalysed conversion into the hitherto unknown 2-benzopyrano[4,3-c]pyrazole ring system 7a,b in good yield. Analytical and spectral data are presented which supported the structures proposed.     

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 .     

Synthesis of 8-substituted naphtho[2,1-b]thiophenes with cationic side chains at position 4

A series of five 8-substituted α-[bis(2-hydroxyethyi)aminoethyl]naphtho[2,1-b]thiophenes 7 and a series of seven N-(3-dimethylaminopropyl)-8-substituted naphtho[2,1-b]thiophene-4-carboxamides 8 have been synthesized. The naphtho[2,1-b]thiophene-4-carboxylic acids 4 were prepared by photooxidative cyclization of α-(2-thienyi)-β-arylacrylic acids 3. The carboxylic acids 4 were converted by a conventional five step route involving α-bromoketone intermediates to the a-[bis(2-hydroxyethyl)aminomethyl]-8-substituted naphtho-[2,1-6]thiophene-4-methanols 7 and by a standard two-step amide preparation to the N-(3-dimethylaminopropyl)-8-substituted naphtho[2,1-6]thiophene-4-carboxamides 8 .     

Studies on condensed heterocyclic compounds II.Synthesis and antibacterial activity of 3-(4''''-pyridyl)-6-aroylamino/arylamino-S-triazolo[3,4-b]-1,3,4-thiadiazoles

3-(4′-Pyridyl)-4-amino-5-mercapto-1,2,4-triazole(1)reacted with aroyl isothiocyanates2a-1 to yield twelve novel 3-(4′-pyridyl)-6-aroylamino-S-triazolo[3,4-b]-1,3,4-thiadiazoles,4a-1.Triethylamine was necessary for the condensation of 1 with phenyl isothiocyanate(3)to give 3-(4′-pyridyl)-6-phenylamino-S-triazolo[3,4-b]-1,3,4-thiadiazole(6).The structures were confirmed bythe elemental and spectral analyses.Their antibacterial activity against B.Subtilis,E.Coli,E.aerogenes and S.aureus was observed preliminary.     

Reaction of 4,5-diamino-3-methyl-1-phenylpyrazole with 3-dimethylaminopropiophenones. Synthesis of new 4-aryl-6-methyl-8-phenyl-2,3-dihydropyrazolo[3,4-b]diazepines and 4-aryl-8-methyl-6-phenyl-2,3-dihydropyrazolo[4,3-b]diazepines

New 4-Aryl-6-methyl-8-phenyl-2,3-dihydropyrazolo[3,4-b]diazepines and 4-aryl-8-methyl-6-phenyl-2,3-dihydropyrazolo[4,3-b]diazepines were obtained from the reaction of 4,5-diamino-3-methyl-1-phenylpyrazole 1 with one equivalent of the 3-dimethylaminopropiophenones 2 in absolute ethanol. The structures of 4-aryl-6-methyl-8-phenyl-2,3-dihydropyrazolo[3,4-b]diazepines 3 and 4-aryl-8-methyl-6-phenyl-2,3-dihydropyrazolo[4,3-b]diazepines 4 were determined by detailed nmr measurements.