Novel Synthesis of N-Arylpyrrole,Pyrrolo[1,2-a]quinazoline,and Pyrrolo[3,4-d]pyridazine Derivatives

Phenacyl-malononitrile derivatives 1a,b react with dimethyl formamide dimethyl acetal (DMFDMA) in refluxing toluene to afford the enaminones 2a,b respectively. Compounds 2a and 2b react with the aromatic amines (aniline, p-toluidine, p-anisidine) in refluxing ethanol to afford the pyrroles 4a–f and with anthranilonitrile and methyl anthranilate to afford the pyrrolo[1,2-a]quinazolines 5a,b and 6a,b respectively. The pyrrole derivatives 4a–f react with hydrazine hydrate and phenyl hydrazine in refluxing ethanol to afford the pyrrolo[3,4-d] pyridazine derivatives 7a–f and 8a–f respectively.     

Synthesis of Fused Isolated Azoles and N-Heteroaryl Derivatives Based on 2-Methyl-3,4-dihydrothieno[3,4-d]pyrimidin-5-amine

In this work, we report the synthesis and characterization of new compounds derived from thieno[d]pyrimidines. The formation of isolated and fused thieno[d]pyrimidine derivatives was achieved via reacting 5-amino-(2-methyl)thieno[3,4-d]pyrimidin-4(3H)-one (3) with some selected reagents. The starting compound (2) was prepared in a quantitative yield using a modified procedure by conversion of the cyano group in 1 to the amide via hydrolysis using concentrated H₂SO₄. Methylthieno[3,4-d]pyrimidin-5-yl (8, 9, and 18), 3-phenylthieno[3,4-e][1,2,4]triazolo[4,3-c]pyrimidines (11–15) and tetrazolo[1,5-c]thieno[3,4-e]pyrimidine (16) have been synthesized in excellent isolated yield. The interaction of N-acetyl derivative 19 with benzaldehyde and/or some nitroso compounds afforded the chalcones and Schiff's bases derivatives 20 and 26a and c respectively. The latter compounds were used as key intermediates in the synthesis of N-acetylpyrazol-3-yl (21a and 21b), 6-phenylpyrimidine-2-(one)thione (22a and b), pyrazolo-1-carbothioamide (25), and thiazolidinone andβ β-lactam derivatives 28a and 28c and 30a and 30c respectively. The structures of these compounds were established by elemental analysis, infrared (IR), mass spectrometry (MS), and NMR spectral analysis.     

Novel Synthesis of Some New Pyridazine and Pyridazino[4,5-d]pyridazine Derivatives

Phenacyl-malononitrile derivatives 1a and b react with dimethylformamide dimethylacetal (DMFDMA) in refluxing toluene to afford the enaminones 2a and b respectively. Compounds 2a and 2b react with the hydrazine hydrate 3a and phenyl hydrazine 3b in refluxing ethanol to afford the pyridazine derivatives 5a–d, presumably via the intermediates 4. Compounds 5a–d, react with hydrazine hydrate 3a to afford the pyridazino[4,5-d]pyridazines 6a–d respectively. The pyridazines 5a and b and the pyridazino[4,5-d] pyridazines 6a and b could be oxidized into the full aromatic systems 7a and b and 8a and b respectively. Compounds 7a and b react also with hydrazine hydrate 3a to afford 8a and b respectively.

New Synthetic Approach to 4-N-Arylaminoazuleno[2,1-d]pyrimides

1-Cyano-2-N,N-dimethylformamidinylazulenes as new synthons directed to heterocycle-fused azulenes were obtained by the condensation of 2-amino-1-cyanoazulenes and N,N-dimethylformamide dimethyl acetal (DMFDMA). 1-Cyano-2-N,N-dimethylformamidinylazulene (2a) and 1-bromo-3-cyano-2-N,N-dimethylformamidinylazulene (2b) reacted with anilines (3a–h) to give 4-N-arylaminoazuleno-[2,1-d]pyrimidines in moderate yields. This reaction provides a new procedure for synthesis of pyrimidine-fused azulenes.     

Fused quinoline heterocycles X. First synthesis of new four heterocyclic ring systems 10-amino-6,9-disubstituted-[1,2,4]triazino[4′,3′:1,5]pyrazolo[4,3-c]quinoline derivatives

A novel, simple, and efficient synthetic methodology for the synthesis of hitherto unreported tetracyclic 10-amino-6,9-disubstituted-[1,2,4]triazino[4′,3′:1,5]pyrazolo[4,3-c]quinolines, in one step, has been developed by coupling of various active methylene compounds with diazotized heterocyclic amines. Reacting 2,4-dichloroquinoline-3-carbonitrile (1) with cyanoacetic acid hydrazide (2) in the presence of triethylamine in refluxing MeOH gave the unexpected 3-amino-4-chloro-1H-pyrazolo[4,3-c]quinoline (4), instead of the desired tetracyclic ring system 3 (Scheme 1). Refluxing 4 with excess of cyclic secondary amines 5a–c in boiling dimethylformamide yielded the corresponding 4-amino-pyrazolo[4,3-c]quinolines 6a–c. Diazotization of compounds 4 and 6a–c with sodium nitrite and concentrated HCl at ?5?°C gave the corresponding diazonium salts 17a–d, which were then subjected to couple with different active methylene nitriles, namely, 2-cyanothioacetamide (12), ethyl cyanoacetate (13), malononitrile (14), 2-cyanoacetamide (15), and 2-cyano-N-phenylacetamide (16), in aqueous ethanol containing sodium acetate as a buffer solution. The coupling reaction of diazonium salts 17 with 12, 13, and 14 leading to the novel perianellated tetracyclic ring system 10-amino-6,9-disubstituted-[1,2,4]triazino[4′,3′:1,5]pyrazolo[4,3-c]quinolines 19, 23, and 27, respectively, in one step, is described for the first time. On the other hand, coupling reaction of diazonium salt 17a with both 15 and 16 yielded the previously unknown tetracyclic 10-amino-6-chloro-[1,2,4]triazino[4′,3′:1,5]pyrazolo[4,3-c]quinoline-9-carboxamides 28a and 28b, respectively (Scheme 6). No chromatographic techniques have been used for the purification of the products. The structures of all the newly synthesized compounds were unambiguously confirmed by spectroscopic and analytical techniques.     

Strukturelle Abwandlungen an partiell silylierten Kohlenhydraten mittels Triphenylphosphan-Azodicarbonsäureester, 5. Mitt.: Transformationen an Glykonolactonen

Reaction ofD-glucono-1,5-lactone1 with two equivalents oft-butyldimethylchlorosilane yields via a ringcontraction 2,6-bis-O-(t-BDMSi)-D-glucono-1,4-lactone2a as main product and a small amount of 5,6-bis-O-(t-BDMSi)-D-glucono-1,4-lactone2c. Under the same conditionsL-mannono-1,4-lactone3 is transformed to the derivatives 2,6-bis-O-(t-BDMSi)-L-mannono-1,4-lactone3a and 3,6-bis-O-(t-BDMSi)-L-mannono-1,4-lactone3c as the minor product. 2,6-bis-O-(t-BDMSi)-D-galactono-1,4-lactone4a and 2,6-bis-O-(t-BDMSi)-D-gulono-1,4-lactone5a are also prepared from the corresponding glyconolactones4 and5. Whereas the compounds2a, 2c, 4a and5a withAc ₂O-pyridine give the bisacetylderivatives2b, 2d, 4b and5b, 3c is converted by an accompanying migration of one silylgroup to the 5,6-bis-O-(t-BDMSi)-2,3-bis-O-acetyl-L-mannono-1,4-lactone3d. The gluconolactone derivative2a reacts easily withTPP/DEAD/HX to the 5-X-L-idono-1,4-lactone derivatives6a (X=N₃),6b (X=p-NO₂-C₆H₄COO) and6c (3-O-acetylderivative of6a). Treating6b with a second equivalentTPP/DEAD/HX leads to the unsaturated sugarlacton7b. Without an external nucleophile2a affords withTPP the mixture of 2,6-bis-O-(t-BDMSi)-3,5-carbonato-D-glucono-1,4-lactone2c, 3,5-anhydro-L-idono-1,4-lactone8 and 3,6-anhydro-D-glucono-1,4-lactone9. Analogous procedures applied to4a yield theL-altronolactonoderivatives10a, 10b and10c, the unsaturated sugarlactone11b on the one and the 3,5-carbonatogalactonolactone4c and the 2,6-bis-O-(t-BDMSi)-3-desoxy-5-ethoxycarbonyl-D-threo-hex-2-en-1,4-lactone12 on the other hand.Whereas the bis-silyletherderivative3a is transformed by the title system exclusively by an elimination process to13, the derivative5a affords withTPP/DEAD without any elimination the 3,6-anhydrosugar14. Partial desilylation of14 followed by acetylation gives the derivatives14a and14b.Structural elucidations were achieved by¹H-NMR-analysis. In some cases also CD-measurements allowed suitable correlations.

Mark, E., Zbiral, E., Brandstetter, H. H., 4. Mitt., Mh. Chem.111, 289 (1980).     

Efficient Synthesis and Fungicidal Activities of 2-Alkylthiobenzofuro[3,2-d]Pyrimidinones

2-Alkylthiobenzofuro[3,2-d]pyrimidinones 5 and 6 were synthesized by S-alkylation of 2,3-dihydro-2-thioxobenzofuro[3,2-d]pyrimidin-4(1H)-ones 4, which were obtained via aza-Wittig reaction of iminophosphorane 2 with CS₂ and further reaction of the product with various amines. Compounds 5 and 6 exhibited fungicidal activity. For example, compound 6a, which has a small N-substituted methyl group, showed the best inhibitive activity (91%) against Dothiorella gregaria at 50 mg/L.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

1,3-Disubstitutedpyrazole-4-caboxaldehyde in Heterocyclic Synthesis: A Novel Synthesis of Pyridine-2(1H)-thione and Fused Nitrogen and/or Sulfur Heterocyclic Derivatives

Pyridine-2(1H)-thione 5 was synthesized from the reaction of 3-[3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl]-1-phenylpropenone (3) and cynothioacetamide (4). Compound 5 reacted with halogented compounds 6a–e to give 2-S-alkylpyridine derivatives 7a–e, which could be in turn cyclized into the corresponding thieno[2,3-b]-pyridine derivatives 8a–e. Compound 8a reacted with hydrazine hydrate to give 9. The latter compound reacted with acetic anhydride (10a), formic acid (10b), acetic acid, ethyl acetoacetate, and pentane-2,4-dione to give the corresponding pyrido[3′,2′:4,5]thieno-[3,2-d]pyrimidine 13a,b, pyrazolo[3′,4′:4,5]thieno[3,2-d]pyridine 14 and thieno[2,3-b]-pyridine derivatives 18 and 20, respectively. Alternatively, 8c reacted with 10a,b and nitrous acid to afford the corresponding pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine 24a,b and pyrido[3′,2′:4,5]thieno[3,2-d][1,2,3]triazine 26 derivatives, respectively. Finally compound 5 reacted with methyl iodide to give 2-methylthiopyridine derivative 27, which could be reacted with hydrazine hydrate to yield the corresponding pyrazolo[3,4-b]-pyridine derivative 29.     

四-(p-羟基苯基)杯[4]间苯二酚芳烃的烃基化和酰胺化反应

间苯二酚和对羟基苯甲醛在盐酸/乙醇中缩合生成四-(p-羟基苯基)杯[4]间苯二酚芳烃(1), 在K₂CO₃/丙酮体系中将1分别与溴乙酸乙酯、溴丙烯、N,N-二丙基氯乙酰胺反应可得到全氧烃基化产物2a～2c. 含有12个乙氧基羰基甲氧基支链的2a被苯乙胺、N,N-二甲基二丙胺或三乙烯四胺直接胺解生成杯[4]间苯二酚芳烃酰胺衍生物3a～3c. 2a经过碱性水解、酰氯化、胺化反应转化为含吡啶基的酰胺衍生物3d. 化合物结构都用¹H NMR, IR和元素分析等方法进行了表征.     

Synthesen und Eigenschaften ethinylierter und trimethylsilylethinylierter Molekülsysteme mit 1,6-Methano[10]annulen-Partialstruktur

2-Trimethylsilylethinylated 1,6-methano[10]annulene1 a was obtained by reaction of 2-bromo-1,6-methano[10]annulene with trimethylsilylacetylene in the presence of bis-(triphenylphosphin-)-Pd (II) chloride and Cu(I) and also by reaction of 1,1-diiodo-2-(1,6-methano[10]annulene-2-yl)-ethene (2) withn-buthyl-lithium followed by hydrolysis.1 a reacts with 2N NaOH to 2-ethinyl-1,6-methano[10]annulene (1 b). 2,7- and 2,10-dibromo-1,6-methano[10]annulene can be substituted to give the trimethylsilylethinylated compounds3 a–6 a, which then can be transformed with 2N NaOH into the desilylated products3 b–5 b.

Wolfgang Kraus, Stuttgart-Hohenheim, mit den besten Wünschen in Freundschaft zum 60. Geburtstag gewidmet     

Synthesis and Antitumor Evaluation of Some Newly Synthesized Pyrazolopyrimidine and Pyrazolotriazolopyrimidine Derivatives

A series of novel pyrazolo[3,4-d]pyrimidine 2b, 3, 5b, pyrazolotetrazolopyrimidine 4, and pyrazolotriazolopyrimidine derivatives 6a,b–10a,b have been synthesized and characterized by elemental analysis and spectroscopic data. Furthermore, the cytotoxicity and in vivo antitumor evaluation of some prepared compounds have been assessed, and derivatives 1a and 6b revealed promising activity in comparison to that of Cisplatin.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis and in vitro anticancer activity of pyrazolo[1,5-a]pyrimidines and pyrazolo[3,4-d][1,2,3]triazines

A novel series of pyrazolo[1,5-a]pyrimidines 14a–j and pyrazolo[1,5-a]quinazolines 18a, b were synthesized via condensation of 5-amino-1H-pyrazoles 10a, b with 3-(dimethylamino)-1-aryl-prop-2-en-1-ones 11a–e and 2-((dimethylamino)methylene)-5,5-dimethylcyclohexane-1,3-dione (15), respectively, in glacial acetic acid. Finally, treatment of 10a, b with sodium nitrite (NaNO₂) afforded pyrazolo[3,4-d]triazines 20a, b. Structures of compounds were confirmed by their spectral data. These compounds were screened for their in vitro cytotoxic activities against human cancer cell lines (HepG-2 and MCF-7) using 3-[4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The results reveal that, the compounds 14b and 14h were the most potent in comparison with doxorubicin. The structure–activity relationship was discussed.     

BENZOQUINOLINES II. SYNTHESIS OF SOME NEW BENZO[h] PYRIMIDO [4′,5′:4,5]THIENO[2,3-b]QUINOLINE DERIVATIVES AND RELATED FUSED HEXACYCLIC SYSTEMS

Abstract

Reaction of 8-amino-7-(2 furyl)-5,6-dihydrobenzo[h]thieno[2,3-b]quinoline-9-carbonitrile (3a) with phenyl isothiocyanate, triethyl orthoformate, ethylenediamine and/or sodium azide afforded benzo[h]thieno[2,3-b]quinolines 4,7,20 and 25 respectively. Cyclization of thiourea derivative 4 furnished thioxopyrimidine derivative 5. The dithioxopyrimidine 6 was prepared by reaction of 3a with carbon disulfide. On treatment of 7 with hydrazine hydrate, 10-amino-7-(2-furyl)-11-imino-5,6,10,11-tetrahydrobenzo[h]pyrimido[4′,5′:4,5]thieno [2,3-b]quinoline (8) was obtained. Compounds 8,20 and 25 were used as key intermediates in the synthesis of the fused hexacyclic compounds 9–19, 21–24 and 26–28 respectively. 8-Amino-7-(2-furyl)-5,6-dihydrobenzo[h]thieno[2,3-b]quinoline-9-carboxamide (3b) was reacted with some reagents, namely triethyl orthoformate, benzaldehyde, carbon disulfide, phenyl isothiocyanate, and/or acetic anhydride to give the corresponding benzo[h]pyrimido [4′,5′: 4,5]thieno[2,3-b]quinolines 29, 30, 31, 32 and 34. Compound 29 underwent some sequence reactions to give 37–42. Some of the prepared compounds were tested in vitro for their antibacterial and antifungal activities.     

Microwave‐Assisted Synthesis of 10‐(Phthalimidoalkyl)‐halosubstitutedpyrido [3,2‐b][1,4]‐benzothiazine in Dry Media

N‐Alkylation of 10H‐9‐fluoropyrido[3,2‐b][1,4]‐benzothiazine 5a, 10H‐7‐fluoropyrido[3,2‐b][1,4]‐benzothiazine 5b, and 10H‐7‐chloropyrido[3,2‐b][1,4]‐benzothiazine 5c with different N‐(bromoalkyl)phthalimides using anhydrous K₂CO₃ and tetrabutylammonium bromide (TBAB) under dry conditions with microwave irradiation leads to the formation of 10‐(phthalimidoalkyl)‐halosubstitutedpyrido[3,2‐b][1,4]‐benzothiazine (6a–f) along with some unidentified product. Compound 5a is a new azaphenothiazine derivative and was obtained from hitherto unknown 2‐acetylamino‐3‐fluorophenyl‐3′‐nitro‐2′‐pyridylsulfide 4a via Smiles rearrangement. Compound 4a is required for the synthesis and has been prepared starting from 2‐amino‐3‐fluorobenzenethiol 1a in three steps.     

Pyridine-2(1H)-thione in Heterocyclic Synthesis: Synthesis of Some New Nicotinic Acid Ester,Thieno[2, 3-b]pyridine,Pyrido[3′, 2′: 4, 5]thieno [3, 2-d]pyrimidine,and Thiazolylpyrazolo[3, 4-b]pyridine Derivatives

Nicotinic acid esters 3a–c were prepared by the reaction of pyridine-2(1H)-thione derivative 1 with α-halo-reagents 2a–c. Compounds 3a–c underwent cyclization to the corresponding thieno[2, 3-b]pyridines 4a–c via boiling in ethanol/piperidine solution. Compounds 4a–c condensed with dimethylformamide-dimethylacetal (DMF-DMA) to afford 3-{[(N,N-dimethylamino)methylene]amino}thieno[2, 3-b]- pyridine derivatives 6a–c. Moreover, compounds 4a–c and 6a–c reacted with different reagents and afforded the pyrido[3′,2′:4, 5]thieno[3, 2-d]pyrimidine derivatives 10a–d, 11a–c, 12a,b, 14a,b, 17, and 19. In addition, pyrazolo[3, 4-b]pyridine derivative 20 (formed via the reaction of 1 with hydrazine hydrate) reacted with ethylisothiocyanate yielded the thiourea derivative 21. Compound 21 reacted with α-halocarbonyl compounds to give the 3-[(3H-thiazol-2-ylidene)amino]-1H-pyrazolo[3, 4-b]pyridine derivatives 23a–c, 25, and 27a,b.     

SOME MONOCYCLIC AND SPIROCYCLIC FLUOROPHOSPHORANES CONTAINING 6- AND 7-MEMBERED RINGS

Abstract

The reaction of 2,2-dimethyl-(1,8-naphtho[c,d])-1,3,2-dioxysilenin (3) and 2,2-dimethyldibenzo-1,3,2-dioxysilepin (4) with (C₆H₅)₂PF₃ gave the expected monocyclic fluorophosphoranes. Reaction of the same siloxy compounds with PF₅ gave products which could not be purified but whose ¹⁹F nmr spectra suggested that the desired spirocyclic compounds were present in the impure products. Reaction of the siloxy compounds with C₆H₅PF₄ did not yield identifiable products. The ¹⁹F nmr spectra of the products obtained are discussed and structures are tentatively assigned.     

Synthesis of Some Pyrazolo[3, 4]pyrimidine Derivatives for Biological Evaluation

Abstract

A novel β -enaminonitrile of 1-(6-p-tolyl-pyridazin-3-yl)-pyrazole derivative 2 was formed using (6-p-tolyl-pyridazin-3-yl)-hydrazine ( 1 ) and 2-ethoxymethylenemalononitrile. The β-enaminonitrile derivative 2 was in turn used as a precursor for the preparation of pyrazoles ( 4 , 6 ), pyrazolo[3, 4-d]-pyrimidines ( 3 , 7–12 ) and pyrazolo[4, 3-e][1,2,4]triazolo[4,3-c]pyrimidine ( 13 ). Also, N- and S-acyclic nucleosides 14 and 15 were prepared. Some of the prepared products showed potent antimicrobial activity.     

Synthesis of Polyfunctionally Substituted Pyrazolonaphthyridine,Pentaazanaphthalene, and Heptaazaphenanthrene Derivatives

6-aminopyrazolo[3,4-b]pyridine-5-carbonitrile (2) was used as a precursor for the synthesis of a variety of pyrazolo[3,4-b][1,8]naphthyridines (3, 4) and pentaazacyclopenta[b]naphthalenes (5–10, 13, 14) via the initial addition to either the cyano or amino group followed by cyclization. Also, a series of heptaazadicyclopenta[a,g]naphthalenes (15–17) and heptaazacyclopenta[b]phenanthrenes (18, 19) were obtained via the interaction of 4-(dibenzothiophen-2-yl)-1,5-dihydro-5-imino-3-methyl-1-phenyl-1,2,6,8,9-pentaazacyclopenta[b]naphthalen-6-ylamine (14) with different reagents. The structures of the synthesized compounds were established by elemental and spectral analyses.     

Metal ion-assisted assembly of one-dimensional polyrotaxanes incorporating cucurbit[6]uril

Three cucurbit[6]uril (CB[6])-based polyrotaxanes [Cu(H₂ C6N4)(CB[6])]Cl₄·12H₂O (1), [Co(H₂ C6N4)(CB[6])]Cl₄·14H₂O (2) and [Ag(C6N4)(CB[6])]NO₃·7H₂O (3) are prepared using N,N′-bis(4-pyridylmethyl)-1,6-hexanediamine (C6N4) threading into CB[6]'s and metal ions' assistance. Single-crystal X-ray diffraction analyses reveal that polyrotaxanes 1, 2 and 3 all have 1D chain structure where 1 and 2 are linear and 3 has two shapes, linear and sawtooth, respectively. The effects of guest molecules, metal and counter ions as well as intermolecular weak interactions on the architectures of polyrotaxanes are discussed.     

Copper(I) halide complexes with a sterically hindered thiourea: synthesis and crystal structures of [Cu(dchtu)2Cl] and [Cu(dchtu)2Br] (dchtu = N,N ′-dicyclohexylthiourea)

Copper(I) complexes with a sterically hindered thiourea, [Cu(dchtu)₂X] (dchtu = N,N′-dicyclohexylthiourea; X=Cl 1, Br 2), were synthesized and their crystal structures were determined. Compounds 1 and 2 are isostructural orthorhombic, space group P2₁2₁2₁. Crystallographic data for 1 : a = 13.1711(13), b = 14.2610(19), c = 15.793(2) Å, V = 2966.4(6) ų, Z = 4. For 2 : a = 13.2628(13), b = 14.3410(19), c = 15.860(2) Å, V = 3016.5(6) ų, Z = 4. The stoichiometry of CuX complexes with thiourea is influenced by substituents on the nitrogens. Copper(I) halides only form bis-adducts with the sterically hindered dchtu ligand even with molar excesses of dchtu due to steric hinderance of the cyclohexyl substituents. In 1 and 2, the Cu(I) is trigonally coordinated by the sulfur atoms of two monodentate N,N′-dicyclohexylthiourea ligands and one halide. The structures of the complexes are stabilized by a system of intermolecular H-bonding.