Synthesis of some 5H-benzo[a]phenothiazin-5-one derivatives

Several substituted 6-anilino-5H-benzo[a]phenothiazin-5-one derivatives were prepared by condensation of substituted 1,4-naphthoquinones with 2-aminobenzenethiol in pyridine. The reduction and acetylation of the resulting compounds were also investigated.

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Synthese einiger 5H-Benzo[a]phenothiazin-5-on-Derivate

Zusammenfassung Es wurden mittels Kondensation substituierter 1,4-Naphthochinone mit 2-Aminothiophenol in Pyridin einige substituierte 6-Anilino-5H-benzo[a]phenothiazin-5-one dargestellt. Die Reduktion und Acetylierung der resultierenden Verbindungen wurde ebenfalls untersucht.

     

The synthesis of crowned phenoselenazinone derivatives

Summary Several substituted crowned phenoselenazin-16-one derivatives were prepared by condensation of substituted zinc 2-amino-benzeneselenolates with 1,4-quinone of benzo[15]crown-5 or its dibromide in alcoholic solution. The dehalogenation of the bromoselenazinones was also investigated.

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Synthese von Kronen-Phenoselenazinon-Derivaten (Kurze Mitt.)

Zusammenfassung Es wurden einige substituierte Kronen-Phenoselenazin-16-on-Derivate mittels Kondensation von substituierten Zink-2-aminobenzolselenolaten mit dem 1,4-Chinon von Benzo[15]krone-5 oder seinem Dibromid in alkoholischer Lösung dargestellt. Die Dehalogenierung der Bromselenazinone wurde ebenfalls untersucht.

     

Synthesis of crowned phenoxazine derivatives

Summary 16H-2,5,8,11,14-Pentaoxacyclopentadecano[2,3-a]phenoxazin-16-one, its 17-bromo analogue and 16-hydroxy-2,5,8,11,14-pentaoxacyclopentadecanophenoxazine were prepared by the reaction of 1,4-quinone of benzo[15]crown-5 or its dibromide with 2-aminophenol. Dehalogenation of the bromophenoxazinone was also investigated.

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Synthese von Kronen-Phenoxazin-Derivaten (Kurze Mitt.)

Zusammenfassung 16H-2,5,8,11,14-Pentaoxacyclopentadecano[2,3-a]phenoxazin-16-on, sein Brom-Analog und 16-Hydroxy-pentaoxacyclopentadecanophenoxazin wurden mittels der Reaktion des 1,4-Chinons von Benzo[15]krone-5 oder dessen Dibromid mit 2-Aminophenol hergestellt. Die Dehalogenierung von Bromphenoxazinon wurde ebenfalls untersucht.

     

Synthesis of 6-oxopyrimidin-1(6H)-yl benzamide derivatives and evaluation of their antibacterial and cytotoxic activity

A series of novel 2-alkylamino and 2, 4-dialkyl amino 6-oxopyrimidin-1(6H)-yl) benzamide derivatives were prepared in good yields from a base-catalyzed ring opening of oxadiazolo[3,2-a]pyrimidin-5-one and evaluated for their antibacterial and cytotoxicity. Most of the compounds exhibited antibacterial activity. In particular, compounds 5b and 5k exhibited considerable antibiotic activity against Klebsiella pneumonia and Bacillus cereus. In addition, compounds 5g and 5i also inhibited the growth of two human tumor cell lines (A549 and H460) at micromolar concentrations.     

Simple synthesis of 6-alkyl-5H-benzo[a]phenoxazin-5-ones

6-Alkyl-5H-benzo[a]phenoxazin-5-ones were prepared by the reaction of 5H-benzo[a]phenoxazin-5-one with carboxylic acid in the presence of silver ion and peroxydisulfate.

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Eine einfache Synthese von 6-Alkyl-5H-benzo[a]phenoxazin-5-onen (Kurze Mitteilung)

Zusammenfassung 6-Alkyl-5H-benzo[a]phenoxazin-5-one wurden mittels Reaktion von 5H-Benzo[a]phenoxazin-5-onen mit Carbonsäuren in Gegenwart von Silberionen und Peroxydisulfat dargestellt.

     

Synthesis of 5-[2-(Phenoxy)ethyl] Derivatives of 6-Methyluracil, 6-Methyl-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one,and 2-Imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one

A synthesis of novel derivatives of 6-methyluracil, 6-methyl-2-thioxo-, and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one containing a 2-(phenoxy)ethyl substituent at position 5 of the pyrimidine ring has been carried out. It was found that 5-[2-(phenoxy)ethyl] derivatives of 6-methyl-2-thioxo- and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one are obtained by the condensation of the corresponding ethyl 3-oxo-2-(2-phenoxyethyl)butanoates with thiourea or guanidine. 6-Methyl-5-[2-(phenoxy)ethyl]uracils can be prepared by treating 6-methyl-5-[2-(phenoxy)ethyl]-2-thioxo-2,3-dihydro-1H-pyrimidin-4-ones with an excess of aqueous monochloroacetic acid solution. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1213–1217, August, 2005.     

Pyrimidinthiones (Part I): Utility of 2-Thioxopyrimidin-6-(1H)ones as Ring Transformer in the Synthesis of Fused Bi- and Tri-Cyclic Heterocyclic Compounds and Their Potential Biological Activities

The pyrimidinethiones have wide biological and pharmaceutical activities, that have attracted considerable interest in recent years especially as antiviral inhibiting production of hepatitis B virus (HBV), and in vitro insulin-mimetic. Activity of the complexes of pyrimidinone derivatives evaluated from 50% inhibitory concentration promoted us to study the transformation of the 2-thioxopyrimidin-6(1H) ones to fused bi- and tri-cyclic heterocyclic compounds having the pyrimidine moieties and screening their biological activity.

The reactivity of 2-mercapto-4-aryl-5-cyanopyrimidin-6(1H)ones (1) towards alkylation by different mono and bifunctional halo-organic compounds has been investigated to give S-monoalkylated products 2, 7 and 9; S- and N-dialkylated products 3, 13 and 14. Treatment of 1 and/or 2 with hydrazine hydrate as a nitrogen nucleophile have been investigated to give 4, treatment of 4 with CS₂ and sodium nitrite in the presence of acetic acid (0°C) produced 1,2,4-triazolopyrimidin-5(1H)one derivatives (5)and tetrazolo[1,5-a]pyrimidin-5(1H)ones (6), respectively. Also cyclization of 7 and 9 gave [1,3]thiazolo[3,2-a]pyrimidin-5(1H)one and [1,3]thiazolo[3,2-a]pyrimidin-3,5-dione derivatives 8 and 10 respectively, treatment of 10 with aromatic aldehyde produces 11 which reacted with guanidine HCl to give pyrimido[4,5-d]thiazolo[3,2-a]pyrimidin-6(1H)one derivative 12. Reaction of 14 with o-phenylenediamine was investigated and gave [1,4]quinoxalino[2,3-b][1,3]thiazolo[3,2-a]pyrimidin-9(1H)one derivative 15.     

The dealkylation of 2-diethylamino-3H-phenothiazin-3-one

2-Diethylamino-3H-phenothiazin-3-one was dealkylated to 2-ethylamino-3H-phenothiazin-3-one either by photolysis or pyrolysis.

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Entalkylierung von 2-Diethylamino-3H-phenothiazin-3-on (Kurze Mitteilung)

Zusammenfassung Die Titelverbindung wurde durch Photolyse oder Pyrolyse zu 2-Ethylamino-3H-phenothiazin-3-on entalkyliert.

     

Synthesis of 1-phenyl-6H-anthra[1,9-b,c]furan-6-one (furanoanthrone) derivatives by the reaction of 1-acyloxy-9,10-anthraquinones with benzyl cyanide

The reactions of various I-acyloxyanthraquinones with benzyl cyanide in DMSO in the presence of K₂CO₃ were studied. 1-Phenyl-6H-anthra[1,9-b,c]furan-6-one derivatives are formed as the main reaction products. In the case of unsubstituted I-acyloxyanthraquinones, 1-phenyl-6H-anthra[1,9-b,c[furan-6-one and I-phenylanthra[1,9-b,clpyran-2,l-dione were isolated. It was shown that furanoanthrones can be synthesized in two steps via the corresponding pyronoanthrones.Translated fromlzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2714–2714, November, 1996.     

The dehalogenation of the halo substituted 5H-benzo[a]phenothiazin-5-ones and 3H-phenothiazin-3-ones

6-Bromo- and 6-chloro-5H-benzo[a]phenothiazin-5-ones were dehalinated to 5H-benzo[a]phenothiazin-5-one in the presence of sodium hydrosulfite (disodiumdithionite · 2H₂O) dissolved in aqueous pyridine under nitrogen atmosphere.

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Enthalogenierung von halogensubstituierten 5H-Benzo[a]phenothiazin-5-onen und 3H-Phenothiazin-3-onen

Zusammenfassung 6-Brom- und 6-Chlor-5H-benzo[a]phenothiazin-5-on lassen sich in wäßrigem Pyridin in Gegenwart von Natriumdithionit unter Stickstoff zu 5H-Benzo[a]phenothiazin-3-on enthalogenieren.

     

Amide-based atropisomers in tachykinin NK1-receptor antagonists: synthesis and antagonistic activity of axially chiral N-benzylcarboxamide derivatives of 2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocin-6-one

A series of novel N-benzylcarboxamide derivatives of bicyclic compounds, 3,4-dihydropyrido[3,2-f][1,4]oxazepin-5(2H)-one and 2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocin-6-one, were synthesized by cyclization of N-benzyl-2-chloro-N-(2-hydroxyethyl)- [and -(3-hydroxypropyl)-] nicotinamides, respectively. Atropisomerism was observed in 5-[3,5-bis(trifluoromethyl)benzyl]-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocin-6-ones due to steric hindrance of the carboxamide moiety and restriction of its rotation. Cyclization of N-[3,5-bis(trifluoromethyl)benzyl]-2-chloro-N-[(2S)-3-hydroxy-2-methylpropyl]-5-methyl-4-phenylnicotinamide gave (3S)-5-[3,5-bis(trifluoromethyl)benzyl]-3,8-dimethyl-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3b][1,5]oxazocin-6-one, which exists predominantly in the thermodynamically stable aR-conformer in CDCl₃. This compound showed excellent NK₁-antagonistic activity with IC₅₀ value (in vitro inhibition of [¹²⁵I]-Bolton-Hunter-substance P binding in human IM-9 cells) of 0.47 nM, which is ca. 200-fold more potent than that of its enantiomer, indicating that the atropisomer chirality affects NK₁-receptor recognition.     

Activated nitriles in heterocyclic synthesis: Synthesis of 6-thiophen-2-yl and 6-furan-2-ylthiazolo[2,3—a]pyridine derivatives

A variety of new 6-thiophen-2-yl and 6-furan-2-ylthiazolo[2,3—a]pyridine derivatives could be prepared via the reaction of 2-functionally substituted methyl-2-thiazolin-4-one with cyanomethylenethiophen-2-yl and cyanomethylenefuran-2-yl derivatives. The structure of the reaction products was established based on spectral data.

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Aktivierte Nitrile in der Heterocyclen-Synthese: Die Synthese von 6-Thiophen-2-yl-und 6-Furan-2-yl-thiazolo[2,3—a]pyridin-Derivaten

Zusammenfassung Es konnte eine Reihe neuer 6-Thiophen-2-yl- und 6-Furan-2-yl-thiazolo-[2,3—a]pyridine über die Reaktion von 2-funktionell-substituierten Methyl-2-thiazolin-4-onen mit Cyanomethylenthiphen-2-yl bzw. Cyanomethylenfuran-2-yl-Derivaten hergestellt werden. Die Struktur der Reaktionsprodukte wurde mit spektroskopischen Methoden ermittelt.

     

Oxadiazole condensed ring systems,II: Synthesis of new 2-aryl-1,3,4-oxadiazolo[3,2-a]-s-triazine-5,7(6H)-diones

Summary The syntheses of 1,3,4-oxadiazolo[3,2-a]-s-triazine-5,7(6H)-diones4 through the condensation of 2-amino-5-aryl-1,3,4-oxadiazoles1 with ethoxycarbonyl isocyanate2 is described. Methylation of4b with trimethyl phosphate yielded the N-methyl derivative5.

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Kondensierte Ringsysteme des Oxadiazols, 2. Mitt. [1]: Synthese von neuen 2-Aryl-1,3,4-oxadiazolo[3,2-a]-s-triazin-5,7(6H)-dionen

Zusammenfassung Die Synthese von 1,3,4-Oxadiazolo[3,2-a]-s-triazin-5,7(6H)-dionen4 durch Kondensation von 2-Amino-5-aryl-1,3,4-oxadiazolen1 mit Ethoxycarbonylisocyanat2 wird beschrieben. Die Methylierung von4b mit Trimethylphosphat gibt das N-Methyl-Derivat5.

     

Preparation of benzo[4,5]thiazolo[3,2-a]chromeno[4,3-d]pyrimidin-6-one derivatives using MgO-MgAl2O4 composite nano-powder

MgO-MgAl₂O₄ nanocomposite was prepared from the co-precipitation of Mg(NO₃)₂ and Al(NO₃)₃ salts, characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and fourier transform infrared spectroscopy (FTIR) techniques and evaluated in the synthesis of thirty five derivatives of benzo[4,5]thiazolo[3,2-a]chromeno[4,3-d]pyrimidin-6-ones (d₁-d₃₄) via the multi-component reaction of 4-hydroxycoumarins, aldehydes, and 2-aminobenzothiazole derivatives under solvent free condition. The catalytic activity of MgO-MgAl₂O₄ nanocomposite and the synthesis of the above mentioned compounds were investigated under thermal solvent free (times: 1.4–3 h; yields: 75–95%), ultrasonic irradiation (US) conditions (times: 1–2.5 h; yields: 69–97%) and using high-speed ball milling (HSBM) technique (times: 0.7–2.5 h; yields: 67–97%). In all cases, the products were obtained in excellent yields. Nuclear Magnetic Resonance (NMR) and MASS spectroscopy were used to characterize the structure of the desired product. The mechanism for the preparation of compounds d₁-d₃₄ was proposed and confirmed by ¹H NMR investigations.     

Green synthesis of naphtho[2,3-f]quinolin-13-one and naphtho[2,3-a]acridin-1(2H)-one derivatives catalyzed by heteropoly acid supported montmorillonite K-10 clay

Herein, synthesis of a series of naphtho[2,3-f]quinolin-13-one and naphtho[2,3-a]acridin-1(2H)-one derivatives directly by one-pot multi-component reaction of 1,3-dicarbonyl compounds (1,3-indanedione/1,3-cyclohexanedione), 2-aminoantharacene/2-naphthylamine and various substituted aldehydes under solvent-free conditions using heteropoly-11-molybdo-1-vanadophosphoric acid supported on montmorillonite K-10 clay catalyst (10% PVMoK-10) is reported. The successful formation of naphtho[2,3-f]quinolin-13-one and naphtho[2,3-a]acridin-1(2H)-one derivatives was confirmed by various spectroscopic techniques. This study offers a green approach for the synthesis of novel quinolinone derivatives.     

Synthesis of 5-glycopyranosylamino-pyrano[2,3-d]pyrimidin-2-one derivatives

Summary Three series of 3-substituted 5-glycopyranosylamino pyrano[2,3-d]pyrimidin-2-one derivatives,3 a–c,4 a–c, and5 a–c have been prepared by treatment of the corresponding 1,4-dihydro-6-glycopyranosylamino pyrimidin-4-ones1 a–c with malonic, methyl malonic and ethyl malonic acids, respectively.

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Synthese von Derivaten des 5-Glucopyranosylaminopyrano[2,3-d]pyrimidin-2-on

Zusammenfassung Es wurden drei Serien von 3-substituierten 5-Glucopyranosylaminopyrano[2,3-d]pyrimidin-2-onen (3 a–c,4 a–c und5 a–c) mittels Behandlung der entsprechenden 1,4-Dihydro-6-glucopyranosylamino-pyrimidin-4-one (1 a–c) mit Malon-, Methylmalon- bzw. Ethylmalonsäure dargestellt.

     

Synthesis of Pyrrolo[a]- and Pyrrolo[c]phenanthridine Derivatives and Indolinyl and Indolylsubstituted 6-Phenanthridines

The corresponding Mannich bases have been synthesized by the aminomethylation of 6-methyl-1H-pyrrolo[2,3-a]- and 4-methyl-3H-pyrrolo[3,2-c]phenanthridinium iodides. The interaction of 6-chloro-phenanthridine with indoline and with 5-amino-N-acetylindoline gave the corresponding derivatives of phenanthridine. 6-(1-Indolyl)phenanthridine has been obtained by the dehydrogenation of 6-(1-indolinyl)phenanthridine with manganese dioxide.     

6H-二苯并[b,d]吡喃-6-酮及其衍生物的合成方法研究进展

6H-二苯并[b,d]吡喃-6-酮类化合物因其广泛的生物活性以及荧光性能而越来越受到化学家们的关注。本文综述了6H-二苯并[b,d]吡喃-6-酮类化合物的主要合成方法,包括分子内关环法、碳氢键活化法、合成苯环法、氧化法,并比较了这四类合成方法的优缺点。今后,如何高效、经济、绿色地合成在特定位置含特定取代基的6H-二苯并[b,d]吡喃-6-酮及其类似物,仍是天然产物合成领域的一个重大课题。     

An efficient electrochemical method for a unique synthesis of new derivatives of 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one

The electrochemical oxidation of catechols (1a-c) has been studied in the presence of 6-methyl-1,2,4-triazine-3-thion-5-one 3 in aqueous sodium acetate, using cyclic voltammetry and controlled-potential coulometry. A plausible mechanism for the oxidation of catechols and their reaction with 3 is presented. All the catechol derivatives (1a-c) were converted into 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives (6a-c) through a Michael-type addition reaction of 3 to anodically generated o-quinones. The electrochemical syntheses of 6a-c were successfully performed in one pot in an undivided cell using an environmentally friendly method with high atomic economy.     

Synthesis and Properties of 6-Amino-7-hetaryl-5-R-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles

We have established that when 5-chloro-6-[cyano(2,3-dihydro-1-R-benzo[d]azol-2-yl)methyl]-2,3-pyrazinedicarbonitriles are reacted with nucleophilic reagents (aliphatic and aromatic amines, hydrogen sulfide), annelation of the five-membered ring occurs on the [b] face of the pyrazine with formation of 6-amino-7-hetaryl-5-R-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles and 6-amino-7-(1H-benzo[d]imidazol-2-yl)thieno[2,3-b]pyrazine-2,3-dicarbonitrile respectively. Further heating with excess of acylating reagent leads to formation of a novel heterocyclic system 1H-benzo[4,5]imidazo[1,2-c]pyrazino[2',3':4,5]pyrrolo[3,2-e]pyrimidine. Reaction of vicinal dinitriles with hydrazine hydrate leads to the novel system 1H-pyrrolo[2',3':5,6]pyrazino[2,3-d]pyridazine.