Synthesis of [1,2,4]triazolo[3′,4′:3,4][1,2,4]triazino[5,6-b]indole,tetrazolo[5′,1′:3,4][1,2,4]triazino[5,6-b]indole and their Derivatives

Reactions of 5-ethyl 5H-1,2,4-triazino|5,6-b|indol-3-thione ( 1 ) with various reagents have been studied. 1 and hydrazine hydrate in anhydrous ethanol gave 5-ethyl-3-hydrazino-5H-1,2,4-triazino|5,6-b|indole ( 2 ). This compound was condensed with formic acid and acetic acid to give 10-ethyl-10H-|1,2,4|triazolo|3′,4′:3,4||1,2,4|triazino|5,6-b|indole ( 4 , R=H) and 10-ethyl-1 -methyl-10H-|1,2,4|triazolo-|3′,4′:3,4‖ 1,2,4|triazino|5,6-b|indole ( 4 , R = CH₃), respectively. Treatment of 2 with nitrous acid gave 10-ethyl-10H-tetrazolo|5′,1′:3,4‖ 1,2,4|triazino|5,6-b|indole ( 7 ). Interaction of 2 with acetylacetone in alcoholic KOH gave the pyrazole 8 , whereas reaction of 2 with ethyl acetoacetate in anhydrous ethanol led to the expected hydrazone 9 , which on reflux with alcoholic KOH gives 1-(5-ethyl-5H-1,2,4-triazino| 5,6-b|indol-3-yl)-3-methyl-2-pyrazolin-5-one 10 . Treatment of 2 with ethyl chloroformate gives 11 , which can be converted to 10-ethyl-2,10-dihydro-1H-|1,2,4|triazolo|3′,4′:3,4|triazino|5,6-b|-indol-1-one 12 by fusion.     

Synthesis of [1,2,4]triazolo[3′,4′: 3,4] [1,2,4]triazino[5,6-b]indole derivatives and 3-substituted 5-ethyl-H-1,2,4-triazino[5,6-b] Indole

5-Ethyl-3-hydrazino-5H-1,2,4-triazino|5,6-b|indole ( 2 ) reacts with aromatic aldehydes in anhydrous ethanol to yield substituted arylidene-(5-ethyl-5H-1,2,4-triazino|5,6-b|indol-3-yl)hydrazones 3 . Treatment of 3 with excess SOCl₂ gave 10-ethyl-1-aryl-10H-| 1,2,4]triazolo|3′,4′:3,4| 1,2,4|triazino|5,6-b|indoles 4 , while the reaction of 2 with CS₂ in methanolic KOH afforded 10-ethyl-2,10-dihydro-1 H-| 1,2,4|triazolo|3′,4′3,4‖ 1,2,4|triazino|5,6-b|indol-1-thione ( 5 ). Fusion of 1 with aromatic amines leads to 3-(arylamino)-5-ethyl-5H-1,2,4-triazino|5,6-b|indoles 6 , whereas the reaction of 1 with alkyl or aralkyl halides in anhydrous acetone and in the presence of anhydrous K₂CO₃ results in the alkylation of the thiol group to give the alkylthio or aralkylthio derivatives 7.     

Synthesis,Anti-Inflammatory,and Ulcerogenicity Studies of Novel Substituted and Fused Pyrazolo[3,4-d]pyrimidin-4-ones

In the present investigation, some new pyrazolo[3,4-d]pyrimidin-4(5H)-one derivatives (7–12) as well as fused pyrazolo[3′,4′:4,5]pyrimido[1,2-b]pyridazin-4(1H)-one (14–16) and 7,8,9,10-tetrahydropyrazolo[3′,4′:4,5]pyrimido[1,2-b]-cinnolin-4(1H)-one (17) ring systems were synthesized using the starting compound 5-amino-6-methyl-1-phenyl-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one (5). The structures of the newly synthesized compounds were elucidated by IR, ¹H NMR, ¹³C NMR, mass spectroscopy, and elemental analysis. The theoretical calculation of their lipophilicity as C log P was performed. The anti-inflammatory activity of all newly synthesized compounds was evaluated using the carrageenan-induced paw edema test in rats using indomethacin as the reference drug. Ulcer indices for the most active compounds were calculated. Seven compounds (10b, 11a–f) showed consistently good anti-inflammatory activity. In particular, 5-{[4-(4-bromophenyl)-3-(4-chlorophenyl)-1,3-thiazol-2(3H)-ylidene]amino}-6-methyl-1-phenyl-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one (11e) and its 3,4-bis(4-chlorophenyl) analog (11f) were found to be the most effective among the other derivatives, showing activity comparable to that of indomethacin with minimal ulcerogenic effects. Correlation of the biological data of the active compounds with their theoretically calculated C log P values revealed that lipophilicity influences the biological response.     

Synthesis and antimicrobial activity of [6′-methyl-4′-methoxy-2-oxo-2H-[1]-benzopyran)-2″,4″-dihydro-[1″, 2″, 4″]-triazol-3″-one and 3″-phenyl-thiazolidin-4″-one-phenoxymethyl derivatives of dipyranoquinoline

A series of bioactive 3H,7H,8H,11H-9-[(5″-(6′-methyl-2-oxo-2H-[1]-4′-benzopyranoxy)-2″,4″-dihydro-[1″,2″,4″]-triazol-3″-one)methyl]-3,8,11-trioxo-dipyrano[2,3-f;2,3-c]quinoline (4) and 3H,7H,8H,11H-9-[(2′-(3″-phenyl-thiazolidin-4″-one)-phenoxymethyl]-3,8,11-trioxo-dipyrano[2,3-f;2,3-c]quinoline (7) analogs of 3H,7H,8H,11H-9-bromomethyl-3,8,11-trioxo-dipyrano[2,3-f;2,3-c]quinoline (1) have been synthesized and evaluated for their antibacterial activity against Gram-positive bacteria (S. aureus) and Gram-negative bacteria (S. typhi and E. coli). Pyranoquinolines with triazole and thiazolidine moieties exhibited promising antibacterial activity. The structures of all synthesised compounds were confirmed on the basis of analytical and spectral data.     

Synthesis of new series of pyrazolo[4,3-d]pyrimidin-7-ones and pyrido[2,3-d]pyrimidin-4-ones for their bacterial and cyclin-dependent kinases (CDKs) inhibitory activities

Two series of pyrazolo[4,3-d]pyrimidin-7-ones and pyrido[2,3-d]pyrimidin-4-ones were designed, synthesised, and evaluated for their antibacterial activities and CDKs inhibitory activities. The pyridazine derivative: 6-phenyl-5-phenylhydrazono-2,3,4,5-tetrahydropyridazine-3,4-dione (3a) revealed activity against Staphylococcus aureus as Gram-positive bacteria while compound 2-(2-Ethoxyphenyl-5-Phenylpiperazinosulfonamido)-3H-pyrido[2,3-d]pyrimidin-4-one (13c) was showing moderate antifungal activity against Candida albicans.     

The Biotransformation of 8-Chloro-6-phenyl-4H-s-triazolo[4, 3-a][1,4] benzodiazepine (D-40TA), a New Central Depressant,in Man,Dog and Rat

1. Metabolic studies of 8-chloro-6-phenyl-4H-^s-triazolo [4,3-a] [1,4] benzodiazepine (D—40TA) in man, dog and rat led to identification of the following metabolites: six hydroxylation products; 8-chloro-2,4-dihydro-6-phenyl-1H-s-triazolo[4,3-a] [1,4]benzodiazepin-1-one (I), 8-chloro-6-(4-hydroxyphenyl)-4H-s -triazolo[4,3-a][1,4]benzodiazepine (II), 8-chloro-6- (3-hydroxyphenyl)-4H-s-triazolo[4,3-a] [1,4] benzodiazepine (III), 8-chloro-4-hydroxy-6-phenyl-4H-s- triazolo[4,3-a][1,4]benzodiazepine (IV), 8-chloro-2,4-dihydro-6- (4-hydroxy-phenyl)-1H-s-triazolo[4,3-a] [1,4] benzodiazepin-1-one (V) and 8-chloro-2,4-dihydro-6-(3-hydroxyphenyl)- 1H-s- triazolo[4,3-a][1,4]benzodiazepin-1-one (VI); five ring-opened metabolites; 5-chloro-2-(4H-1,2,4-triazol-4-yl) -benzophenone (VII), 5-chloro-2- (2,3-dihydro-3-oxo- 4H -1,2,4- triazol-4-yl)benzophenone (VIII), 5-chloro-2- (2,3-dihydro-3-oxo-4H - 1,2,4-triazol-4-yl)-2-hydroxybenzophenone (IX), 5-chloro-2- (2,3-dihydro-3-oxo-4H-1,2,4-triazol-4-yl)-4'-hydroxybenzophenone (X) and 5-chloro-2-(3,5-dioxo-2,3,4,5-tetrahydro-1H-1,2,4-triazol-4-yl) benzophenone(XI).

2. In man, metabolites I, IV, VII and VIII are present as the free form in the urine, and I, II, IV and VIII are present as conjugates. In the dog, all the metabolites are present. The rat transforms the compound mainly to metabolites I, II, IV and V. None of the ring-opened metabolites are observed in the rat.     

Zur Totalsynthese des 5-Acetoxy-6-methoxykawains

Total Synthesis of 5-Acetoxy-6-methoxykawain The oxidation of 5-hydroxy-4-methoxy-6-trans-styryl-2H-pyran-2-one ( 6 ) by periodic acid in methanol gives rise to racem.-4,6-dimethoxy-6-trans-styryl-2,5-pyrandione ( 7 ). The yield is 35% Compound 7 is the key intermediate¹⁾ for the total synthesis of (5S, 6S)-(+)-acetoxy-4,6-dimethoxy-6-trans-styryl-5,6-dihydro-2H-pyran-2-one ( 1 ).     

Umsetzung von 1,2-Dihydro-3-indazolon mit ω-Dialkylaminoalkylhalogeniden und α,ω-Dihalogenalkanen

Reaction of 1,2-Dihydro-3-indazolone with ω-Dialkylaminoalkyl Halides and α, ω-Dihalogenalkanes The reaction of the potassium salt of 1,2-dihydro-3-indazolone with ω-dialkylaminoalkyl halides in anhydrous dioxane leads to basic lactim ethers, which are analgesics. On the other hand two basic compounds are formed, when α, ω-dihalogenopropanes participiate. Compound 1 was identified as 3,4-dihydro-2H-[1,3]oxazino[2, 3-b]indazole and compound 2 as 2,3-dihydro-lH-pyrazolo[1,2-a]indazol-9-one. Compound 2 is reduced by LiAlH₄, to 2,3-dihydro-lH, 9H-pyrazolo[1, 2-a]indazole ( 5 ).     

Acetylenchemie, 3. Mitt. Ein einfacher Zugang zum Flindersin via Phasen-Transfer-Reaktion

Acetylene Chemistry, III: A Simple Approach to Flindersine by Phase-Transfer Reaction Reaction of 4-hydroxyquinolin-2-one (4) with 3-chloro-3-methylbut-1-yne by phase-transfer catalysis affords flindersine (3) and 2,3-dihydro-3,3-dimethyl-2-methylenefuro[3,2-c]quinolin-4-one (5) , whereas indolin-2-one (4g) yields N-(1′,1′-dimethylprop-2-yn-1-yl)indolin-2-one (19) . The reaction mechanism is discussed and studied by varying the reaction conditions.     

Neue Pyrrolderivate, 9. Mitt.: Darstellung und Cyclisierungsverhalten von 2-Acylamino-1H-pyrrol-3,4-dicarbonitrilen

New Pyrrole Derivatives, IX: Formation and Cyclization of 2-Acylamino-1H-pyrrolo-3,4-dicarbonitriles 2-Acylaminopyrrole-3,4-dicarbonitriles 3a - f were prepared from the corresponding diamides 2a - f by treatment with -dimethylaniline at 40°C.- By reaction with -dimethylaniline/amine at 150-190°C cyclization to 6-alkylthio-3-arylamino-4-imino-7H-pyrrolo[2,3-d]pyrimidine-5-carbonitriles, e.g. 5a and 5b , can be realized.     

A CONVENIENT ROUTE FOR THE SYNTHESIS OF CIS-1-SUBSTITUTED 1,2,3,4,4a,5,11,11a-OCTAHYDRO-6H-PYRIDO[3,2-b]CARBAZOLES AND 4-SUBSTITUTED 1,2,3,4,4a,5,6,11c-OCTAHYDRO-7H-PYRIDO[2,3-c] CARBAZOLES AS POTENT DOPAMINE AGONISTS

The cis-1/4 substituted octahydropyrido[(3,2-b)/(2,3-c)]carbazoles have shown potent dopamine agonistic activity in vitro and in vivo. The reported method¹ of their synthesis involves hydrogenation at high temperature and pressure. Some attempts have been made to develop new methods.² So in order to explore an alternative method, the key intermediate 4-benzoyloxy cyclohexanone obtained from 1,4-cyclohesanediol by its benzoylation followed by oxidation is used. The 4-benzolyloxycyclohexanone on condensation with acrylamide through enamine intermediate gave 6-benzoyloxy-1, 2,3,4,5,6,7,8-octahydroquinoline-2-one, which on hydrolysis followed by reduction afforded 6-hydroxy-1,2,3,4,4a,5,6,7,8,8a-decahydroquinoline-2-one which on oxidation, Fischer Indolisation and LAH reduction followed by alkylation yielded the desired octahydropyrido-[(3,2-b)/(2,3-c)] carbozoles.     

Derivatives of 3-aminothieno(2,3-d)pyrimidine and of 3-amino(1)benzothieno(2,3-d)pyrimidine (author's transl)]

Derivatives of 3-Aminothieno[2,3-d]pyrimidine and of 3-amino[1]benzothieno[2,3-d]pyrimidine Derivatives of 3-aminothieno[2,3-d]pyrimidin-4(3H)-one and of 3-amino-5,6,7,8-tetrahydro[1]-benzothieno[2,3-d]pyrimidin-4 (3H)-one, both carrying basic substituents at position 2 (general formulae I and II ), were synthesized in an one-step reaction from the corresponding 2-acylamino-thiophene-(or-benzo[b]thiophene)-3-carboxylates with hydrazine.     

Anellierte Thiopyrone, 2. Mitt. Thiopyrano[3,2-b]indol-4(5H)-on- und Thiopyrano[2,3-b]indol-4(9H)-on-2-carbonsäuren

Fused Thiopyrones, II; 2-Carboxylic Acids of Thiopyrano [3,2-b]indol-4(5H)-one and Thiopyrano[2,3-b]indol-4(9H)-one 3-Indolylthiofumaric acids 2 are cyclized by polyphosphoric acid (PPA) to yield the isomeric title compounds 6 and 8 .     

Beiträge zur Chemie des Pyridazinsystems, 29. Mitt. Synthese von 4-Arylpyrimido[4,5-d]pyridazinen aus (5-Amino-4-pyridazinyl)arylketonen

Pyridazine Chemistry XXIX: Synthesis of Pyrimido[4,5-d]pyridazines from (5-Amino-4-pyridazinyl)arylketones The pyrimido[4,5-d]pyridazin-2(1H)ones 4 and 6 are prepared in high yields from the amino ketones 1 or 5 . Procedures for the synthesis of the 4-arylpyrimido[4,5-d]pyridazines 8a, b, c via the imido esters 7a, b, c are described.     

Olefinierungsreaktionen des 5H-Cyclopenta(cd)phenalen-5-on

Olefination Reactions of 5H-Cyclopenta[cd]phenalen-5-one We describe olefination reactions of 5H-cyclopenta[cd]phenalen-5-one (1) with diphenyl ketene, phenyl cyano ketene, tert.-butyl cyano ketene, and methyl cyano ketene to yield compounds 2–6 . Also, further the synthesis of 2-[bis(methylthio)methylene]-2H-naphtho[1,8-bc]thiophene (6) is described.     

Synthese von 5H-Pyrido[2,3-c]-2-benzazepinen

Synthesis of 5H-Pyrido[2,3-c]-2-benzazepines The title compounds can be obtained by two differend ways: Ring closure of 2-benzazepine enaminonitrile 1 and the C₂-building blocks 2, 7 and 8 gives rise to the title compounds 6, 9 and 10 . - The second way starts with Wolff-Kishner-reduction of the 2-amino-3-benzoylpyridines 16a,b to the 2-amino-3-benzylpyridines 18a,b . Benzoylation of 18a,b leads to the dibenzoylated compounds 20 and 21 , respectively, which can be transformed to the monobenzoylated pyridines 22 resp. 23 . Applying the Bischler-Napieralski-reaction on 22a,b and 23a,b leads to the 5H-pyrido[2,3-c]-2-benzazepines 24a,b and 25a,b . By means of ¹H-, ¹³C- and ¹⁵N-NMR-data it is demonstrated that ethyl benzoylcyanacetimidate ( 12a ) exists as benzoylketene-O,N-acetal 12a AE .     

Three new and two rare furanoeremophilanes from senecio asirensis

Three new furanoeremophilanes have been obtained from the aerial parts of Senecio asirensis (N. O. Asteraceae), and characterized as 6-hydroxylmethyl-9-methoxyl-4,11-dimethylnaphtho[2,3-b]furan, designated asirensane-a (1), 6-hydroxyl-1,2-dimethoxyl-4,6,11-trimethyl-6-hydronaphtho[2,3-a]furan-7-one, named asirensane-b (2), and (6,12-dihydroxyl-9-methoxyl-4-methyl-11-acetyl-3,4-dihydronaphtho[2,3-b]furan-3-yl)methyl (2′Z)-2′-methylbut-2′-enoate, designated asirensane-c (3). In addition, two rare furanoeremophilanes have also been isolated and characterized from this source, namely 9-methoxyl-4,11-dimethylnaphtho[2,3-b]furan, named 14-nordehydrocalohastine (4), and 4,11-dimethylnaphtho[2,3-b]furan-6,9-dione, designated as maturinone (5). Their structures have been elucidated on the basis of spectral analysis. The alcoholic extract was also tested for anti-inflammatory activity, which decreased edema by 22% at a dose of 500?mg?kg^-1 after 3?h with respect to the control group treated only with carrageenan, while the standard drug phenylbutazone showed a 50% decrease at a dose of 100?mg?kg^-1, indicating that the extract has moderate anti-inflammatory activity.     

Pyrido[3,4-d]pyrimidin-4(3H)-one metabolism mediated by aldehyde oxidase is blocked by C2-substitution

1.?We have previously described C8-substituted pyrido[3,4-d]pyrimidin-4(3H)-one derivatives as cell permeable inhibitors of the KDM4 and KDM5 subfamilies of JmjC histone lysine demethylases.

2.?Although exemplar compound 1 exhibited moderate clearance in mouse liver microsomes, it was highly cleared in vivo due to metabolism by aldehyde oxidase (AO). Similar human and mouse AO-mediated metabolism was observed with the pyrido[3,4-d]pyrimidin-4(3H)-one scaffold and other C8-substituted derivatives.

3.?We identified the C2-position as the oxidation site by LC-MS and ¹H-NMR and showed that C2-substituted derivatives are no longer AO substrates.

4.?In addition to the experimental data, these observations are supported by molecular modelling studies in the human AO protein crystal structure.     

Synthesis characterization and biological evaluation of some alkoxyphthalimide derivatives of 3-(4-substituted phenyl)-6,6-diphenyl-3,3a-dihydro-2H-imidazo[2,1-b]pyrazolo[3,4-d][1,3]thiazol-7(6H)-one

A series of 2-N-ethoxyphthalimido 3-(4-substitutedphenyl)-6,6-diphenyl-3,3a-dihydro-2H-imidazo[2,1-b]pyrazolo[3,4-d][1,3]thiazol-7(6H)-one(7a–e) and 4-(4-substituted phenyl)-2-(N-ethoxyphthalimido amino)-7,7-diphenylimidazo[2′,1′:2,3][1,3]thiazolo[4,5-d] pyrimidin-8(7H)-one (9a–e) have been designed and synthesized starting from thiohydentoin (1). The structure of all synthesized compounds has been established by IR, ¹H NMR, ¹³C NMR and mass studies. These compounds have been screened for antimicrobial activities in order to evaluate the possibility of the derivatives to be used as potential chemotherapeutic agents.     

Reactions with 4-Bromo-3-methyl-1-phenyl-2-pyrazolin-5-one: New Fused Pyrazole Derivatives

New furo[2,3-c]pyrazoles and pyrano[2,3-c]pyrazoles were synthesized from 4-bromo-3-methyl-1-phenyl-2-pyrazolin-5-one and active methylenenitriles, ethyl acetoacetate or phenylhydrazine. The constitutions of the new heterocycles were established by elemental analyses and spectroscopic data.