3-取代-(1H)-嘧啶[1, 2-a]喹啉-1-酮和2-取代嘧啶[1, 2a]苯骈 咪唑-4-(10H)- 酮的简便合成法

本文利用2-氨基喹啉和2-氨基苯骈咪唑作为亲核试剂,与5-(双甲硫基亚甲基)丙二酸亚异丙酯(1)、5-(甲硫基亚烃基)丙二酸亚异丙酯(3)反应,开发出3-取代-(1H)-嘧啶-[1,2-a]喹啉-1-酮(5)和2-取代嘧啶[1,2-a]苯骈咪唑-4-(10H)-酮(6)通用的简便合成法。     

2-Aminothiazole derivatives. III. Mass spectra of some 5H-thiazolo [3,2-a] pyrimidin-5-ones

The mass spectra of some 7-methyl, 7-chloro and 6-earbethoxythiazolo[3,2-a]pyrimidin-5-ones were studied ( 2,3,4 ). The electron impact fragmentation patterns of these compounds showed their relatively high stability and their similar mode of decomposition. Certain differences were observed among the three classes of compounds, due to the nature of the substituent on the pyrimidine ring.     

Synthesis of 3-(2-oxopyrrolidin-1-yl)-2H,3H-[1,3]selenazolo- [3,2-a]pyridin-4-ium chloride

Russian Journal of Organic Chemistry - 2-(Chloroselanyl)pyridine reacted with N-vinylpyrrolidin-2-one in chloroform at room temperature to give...     

Mass spectrometric behaviour of 1-imino-substituted pyrazolo[1,2-a]-[1,2,4]triazoles under electron and chemical ionization

The spectra of five pharmacologically interesting substituted pyrazolo[1,2-a][1,2,4]triazole hydroiodides were measured under electron and chemical ionization. In the electron ionization spectra, in addition to the intense molecular ion peak of the free base (M⁺*), there was also a relatively intense molecular ion peak of the hydroiodide form, which is unusual since the hydroiodides are rarely so stable. The phenylimino and phenylamino substituents of the triazole ring affected the fragmentation behaviour of the compounds very much. The chemical ionization reagent gases used in this work were methane, isobutane, deuterated ammonia and acetone. In all the cases practically only [M+H]⁺ ions were observed, the only exception being acetone which also gave rise to intense [M+C₂H₃O]⁺ and [M⁺C₃H₇O]⁺ adduct ions. None of the reagent gases used was able to cause any fragmentation.     

Microwave assisted synthesis of 2,3-dihydro-4H-benzo[4,5]thiazolo[3,2-a]furo[2,3-d]pyrimidin-4-ones and 6,7-dihydro-5H-furo[2,3-d]thiazolo[3,2-a]pyrimidin-5-ones using Mn(OAc)3

2-Hydroxy-4H-benzo[4,5]thiazolo[3,2-a]pyrimidin-4-one 2a and 7-hydroxy-5H-thiazolo[3,2-a]pyrimidin-5-one 2b, were obtained in high yields under mild conditions from the cyclization reactions of bis-(2,4,6-trichlorophenyl) malonate and 2-aminobenzothiazole or 2-aminothiazole, respectively. A new class of compounds, 2,3-dihydro-4H-benzo[4,5]thiazolo[3,2-a]furo[2,3-d]pyrimidin-4-ones and 6,7-dihydro-5H-furo[2,3-d]thiazolo[3,2-a]pyrimidin-5-ones, were synthesized via the microwave assisted radical addition of compounds 2a and 2b to various alkenes using manganese(III) acetate. A preliminary acetylcholine esterase (AchE) inhibition test of compound 4e showed excellent (92%) inhibitory potential, comparable with the standard drug Donapezil®.     

Some chemical properties of 2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones

We have studied the reaction of 2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones with amines, alkylating reagents, and hydrogen peroxide. We have shown that the presence of an aryl substituent at the 2 position of [1,3-thiazino[3,2-a]benzimidazol-4-ones has a substantial effect on the direction of the reactions. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 445–452, March, 2006.     

Regioselective Synthesis ofPyrano[3,2-f]quinolin-2(7H)-onesand Furo[3,2-f]quinolin-2-ones

Summary.  A simple and efficient synthesis of the hitherto unreported ring systems pyrano[3,2-f]quinolin-2(7H)-one and furo[3,2-f]quinolin-2-one was accomplished via a thermal [3,3]-sigmatropic rearrangement. Received March 7, 2000. Accepted May 4, 2000     

Synthesis of novel thiazolo[3,2-a]chromeno[4,3-d]pyrimidine-6(7H)-ones by bioactive Fe3O4@gly@thiophen@Cu(NO3)2 as reusable magnetic nanocatalyst

In this study, new Fe₃O₄@gly@thiophen@Cu(NO₃)₂ magnetic nanoparticles were synthesized. The final product was used as an efficient and novel magnetic nanocatalyst for synthesizing new derivatives of thiazolo[3,2-a] chromeno[4,3-d]pyrimidine-6(7H) in a short time and with higher efficiency. In the synthesis of Fe₃O₄@gly@thiophen@Cu(NO₃)₂ magnetic nanoparticles, the use of glycine proved an inexpensive and readily available coating for Fe₃O₄ than previously reported materials, and the structure was confirmed using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersive x-ray (EDX) spectroscopy, EDX mapping, Fourier-transform infrared spectroscopy, thermogravimetric analysis/derivative thermogravimetry, and vibrating sample magnetometry. The biological properties of magnetic nanoparticles were evaluated, and they exhibited acceptable antifungal and antibacterial properties in terms of minimum inhibitory concentration, minimum fungicidal concentration, and minimum bactericidal concentration.     

Novel fused-ring derivatives of 2-methyl-3-o-tolyl-4(3H)quinazolone; Quinazolino [3,2-a] [1,4] benzodiazepines

The synthesis of some quinazolino[3,2-a][1,4]benzodiazepines from 2-bromomethyl-3-o-carbomethoxyphenyl-4(3H)quinazolone is described. Alkylation and acylation of N-6 led to a series of novel derivatives of this ring system.     

Photochemistry of 4(3H)-pyrimidin-4-ones. Formation of medium-ring lactams

Upon irradiation, 4(3H)-pyrimidin-4-one(1) afforded a di-imine derivative(2) which, when hydrolyzed in an acidic methanol solution, gave N-methyl acetoacetamide(3). On the other hand, the fused 4(3H)-pyrimidin-4-ones, (4) and (5), gave medium-ring lactams(6) and (7), which were hydrolyzed in an acidic methanol solution to give (8) and (9), respectively.     

A facile synthesis of 3-substituted 2-cyanoquinazolin-4(3H)-ones and 3-alkyl-2-cyanothieno[3,2-d]pyrimidin-4(3H)-ones via 1,2,3-dithiazoles

The reaction of methyl anthranilate with 4,5-dichloro-1,2,3-dithiazolium chloride (Appel's salt) in the presence of pyridine (2 equivalents) in dichloromethane at room temperature gave methyl N-(4-chloro-5H-1,2,3-dithiazol-5-ylidene)anthranilate ( 3a ) (50% yield), which reacted with sterically less hindered primary alkylamines to give directly 3-alkyl-2-cyanoquinazolin-4(3H)-ones 5 in moderate to good yields. With tert-butylamine, N-(2-methoxycarbonylphenyl)iminocyanomethyl N-(tert-butyl) disulfide 7 and methyl 2-(N-cyanothioformamido)anthranilate ( 8 ) were isolated in 33% and 59% yields, respectively. The cyano group of quinazoline 5a (R = CH₃) is readily displaced by various nucleophiles to give 2-substituted quinazolinones 11–19 , which indicates that compounds 5 can be utilized as starting materials for the synthesis of new 2-substituted quinazolines. Similarly 3-alkyl-2-cyanomieno[3,2,-d]pyrimidin-4(3H)-ones 22 were prepared from methyl 3-[N-(4-chloro-5H-1,2,3-dimiazol-5-ylidene)]-2-thiophencarboxylate ( 21 ) in moderate to good yields.     

The synthesis of 1-substituted 6-amino-1H-pyrrolo-[3,2-c]pyridin-4(5H)-ones

The synthesis of 1-methyl- ( 1a ) and 1-benzyl-6-amino-1H-pyrrolo[3,2-c]pyridin-4(5H)-one ( 1b ) from the appropriate N-alkylaminoacetaldehyde is described. These provide examples of a synthetic procedure that can be used to prepare 1-substituted 6-amino-1H-pyrrolo[3,2-c]pyridin-4(5H)-ones wherein the N-1 substituent is regiospecifically placed.     

Preparation of methano[1,3]oxazolo[3,2-a]quinolin-2-ones from 2-(pent-3-en-2-yl)anilines

Acid-catalyzed Claisen aromatic rearrangement of ethyl N-(pent-3-en-2-yl)-N-phenylglycinate leads to the formation of ethyl N-[2-(pent-3-en-2-yl)phenyl]glycinate. The reaction of sodium salt of N-acetyl-2-(pent-3-en-2-yl)-4-methylaniline with methyl bromoacetate afforded ethyl N-acetyl-N-[4-methyl-2-(pent-3-en-2-yl)phenyl]glycinate. The hydrolysis of synthesized esters, the conversion of the obtained acids by treating with ethyl chloroformate into munchnones, and the subsequent [3+2]-cycloaddition provided methoxazoloquinoline structures.     

Synthesis of some new imidazo[1,2-a]pyrimidin-5(1H)-ones as potential antineoplastic agents

Some substituted imidazo[1,2-a]pyrimidin-5(1H)-ones have been synthesized via the reaction of 2-aminoimidazole sulfate with some β-keto esters, diethyl ethoxymethylenemalonate and ethyl ethoxymethylenecyanoacetate. Several compounds were screened for their in vitro antineoplastic and anti-HIV activity but were inactive.     

The synthesis of some benzo[d1]furo[3,2-e] [1,4] diazepin-2-ones

Reaction of 3-amino-2-benzoylbenzo[b]furan with bromoacetyl bromide followed by cyclization in methanolic ammonia gave 5-phenyl-1,3-dihydrobenzo[d′] furo[3,2-e] [1,4]diazepin-2-one, a representative of a new ring-system. The corresponding chloro substituted diazepin-2-one was similarly prepared from 3-amino-2-(4-chlorobenzoyl) benzo[b] furan. Some alkylation and thionation reactions of these diazepines have been investigated.