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1.
A series of carboxylic acid derivatives of the title compounds have been prepared as precursors of potential anti-tumor compounds, by annulation of 2-methylcyclohexanone to the appropriate aminopyridinecarboxaldehyde followed by aromatization and oxidation of the methyl group. 相似文献
2.
A divergent synthesis of substituted benzo[c][2,7]naphthyridines 5a-h is described, which features an intramolecular pyridyne cyclization step as the key reaction. The pyridyne precursors are conveniently prepared from the pyridinium hydrochloride 2 and the requisite anilines. Cyclization of the non-symmetric substrates 3e and 3f did not proceed with significant regioselectivity. 相似文献
3.
Sateesh Kumar Arepalli Byeongwoo Park Jae-Kyung Jung Kiho Lee Heesoon Lee 《Tetrahedron letters》2017,58(5):449-454
A novel series of functionalized 13H-benzo[f]chromeno[4,3-b][1,7]naphthyridines and 1,3-diphenylbenzo[f][1,7]naphthyridines have been synthesized by an efficient regioselective one-pot multicomponent synthesis through intra and intermolecular imino Diels-Alder reaction. In this method, we have achieved complete regioselectivity and atom economy with polysubstituted core motifs in moderate to good yields. The proposed mechanism of this reaction has also discussed. 相似文献
4.
An efficient one-pot method for the synthesis of functionalized quinolines and tetrahydronaphthyridines has been developed. The photo-Fries rearrangement of p-substituted anilides afforded differently substituted o-amino ketones that reacted in situ with acetylenic Michael acceptors such as dimethyl acetylenedicarboxylate (DMAD) to give 6,4-disubstituted quinoline 2,3-dicarboxylates. Starting from anilides derived from β-alanine, a naphthyridine nucleus can also be assembled. 相似文献
5.
Three new 2,4-diaminoquinazolines, the 5,6-difluoro, 6,7-difluoro and 7,8-difluoro isomers were prepared by the reaction of the requisite trifluorobenzonitrile and guanidine carbonate. Surprisingly, 2,3,6-trifluorobenzonitriles gave 2,4-diamino-5,6-difluoroquinazoline exclusively as determined by high resolution nuclear magnetic resonance spectroscopy. On the other hand, 3-amino-2,6-difluorobenzonitrile on reaction with guanidine carbonate yielded only 5-fluoro-2,4,8-triaminoquinazoline. This compound was subsequently converted to 8-chloro-2,4-diamino-5-fluoroquinazoline using the Sandmeyer procedure. The nitration of 2,4-diamino-8-fluoroquinazoline occurred exclusively at position six yielding 2,4-diamino-8-fluoro-6-nitroquinazoline, which upon reduction with stannous chloride afforded 8-fluoro-2,4,6-triaminoquinazoline. In a similar fashion 7-fluoro-2,4-diaminoquinazoline underwent nitration at position six and was then reduced to give 7-fluoro-2,4,6-triaminoquinazoline. Finally, both of these triaminoquinazolines were converted to the 6-chloro derivatives under Sandmeyer conditions to yield 6-chloro-2,4-diamino-8-fluoroquinazoline and 6-chloro-2,4-diamino-7-fluoroquinazoline, respectively. 相似文献
6.
Benzo[c][2,7]naphthyridines bearing electron-withdrawing substituents (bromo, acetyl) at C-4 undergo regioselective homolytic substitutions at C-5 with nucleophilic 1,3,5-trioxanyl and ethoxycarbonyl radicals under Minisci conditions. Surprisingly, mainly 5,6-dihydro derivatives are formed in these reactions. Rearomatization with manganese dioxide leads to 4,5-disubstituted benzo[c][2,7]naphthyridines, which should be attractive building blocks for the synthesis of pyridoacridine alkaloids. Homolytic methylation at C-5 takes place with methyl radicals generated from acetic acid and acetaldehyde, respectively. 相似文献
7.
Yoshinori Tominaga Milton L. Lee Raymond N. Castle 《Journal of heterocyclic chemistry》1981,18(5):967-972
All isomers of the parent anthra[b]thiophenes and benzo[b]naphtho[d]thiophenes, namely anthra[2,3-b]thio-phene, anthra[2,1-b]thiophene, anthra[1,2-b]thiophene, benzo[b]naphtho[2,3-d]thiophene, benzo[b]naphtho[2,1-d]thiophene and benzo[b]naphtho[1,2-d]thiophene were synthesized using a new procedure. 相似文献
8.
A novel benzo [ 1,5] oxazepin-4-one skeleton compound and its four derivatives were synthesized effectively from 1,5-difluoro- 2,4-dinitrobenzene (DFDNB) under mild conditions. In the process, four intermediates were synthesized by substitutions of the two fluorine atoms and reductions of the meta-dinitro groups in DFDNB respectively. The results showed that the key for synthesizing the intermediates was the substitution of one of the two fluorine atoms in DFDNB by 3-hydroxy butyric acid ethyl ester first, then the other fluorine atom by morpholine, and then the reduction of the meta-dinitro groups in the substitute by HCOONH4 with Pd/C. The products were purified with silica gel column chromatography, and confirmed by HPLC, LC-MS and 1H NMR. They should contribute to construct the molecular libraries for therapeutic applications. 相似文献
9.
Previously unknown 2,4-diamino-substituted benzo[g]quinolines were synthesized from 2,4-dihydroxybenzo[g]quinoline. 相似文献
10.
Rakhi Pathak 《Tetrahedron》2006,62(12):2820-2830
Starting from simple indole precursors the synthesis of naphtho[a]carbazoles and benzo[c]carbazoles is described. Key steps include the use of the Suzuki-Miyaura reaction to afford 2- or 3-aryl substituted indoles, as well as a potassium t-butoxide and light assisted aromatic ring-forming reaction. 相似文献
11.
12.
W. Czuba 《Chemistry of Heterocyclic Compounds》1979,15(1):1-13
Methods for the preparation of 1,5-, 1,6-, 1,7-, and 1,8-naphthyridines and their chemical properties are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 3–16, January, 1979. 相似文献
13.
14.
Condensation of arylidene-2-naphthylarnines with 5,5-dimethylcyclohexane-1,3-dione (dimedone) gives novel 2,2-dimethyl-5-R-1,2,3,4,5,6-hexahydrobenzo[a]phenanthridin-4-ones. Treatment of azomethines containing an ortho hydroxyl group in the aldehyde fragment gives the corresponding 3,3,6,6-tetramethyl-9-R-1,2,3,4,5,6,7,8-octa-hydroxanthene-1,8-diones. The IR, UV, PMR, and mass spectra of the compounds synthesized have been studied. 相似文献
15.
16.
The general ability of appropriate pyridyl compounds (aldehyde or ketone) to undergo Friedländer condensation to give different 1,7‐naphthyridines has been demonstrated. 2,4‐Disubstituted 1,7‐naphthyridine 8 was prepared from 3‐amino‐4‐acetylpyridine ( 6 ) and ketone 4 (82%). The Friedländer self‐condensation of pyridyl substrate 6 is reported, as well. The dimer product, 2‐(3‐aminopyridin‐4‐yl)‐4‐methyl‐1,7‐naphthyridine ( 7 ), was obtained in 97% yield. 2‐Aryl‐ and 2,3‐diaryl‐1,7‐naphthyridines ( 16 , 17 , 18 ) were prepared from 3‐aminoisonicotinaldehyde ( 13 ) and arylketones 4 , 14 , and 15 (28–71%). The key substrates 6 and 13 are readily available via the improved pyridine nitration method. J. Heterocyclic Chem., (2011). 相似文献
17.
Seven benzo[b]naphtho[2,3-d]thiophenes have been prepared with methyl groups substituted in the 6,7, and 8-positions. These compounds are structurally related to the sulfur analogs of cholanthrene and methylcholanthrene. 相似文献
18.
19.
This paper discusses the synthesis of benzo[1,4]oxazin-3-one-based compounds from 1,5-difluoro-2,4-dinitrobenzene (1), including benzo[1,4]oxazin-3-ones (5-11) and five novel benzo[1,4]oxazin-3-one-based tricycles: 6-hydroxy-4H-1-oxa-4,5,8-triazaanthracen-3-one (14), 3,8-dihydro-5-oxa-1,3,8-triazacyclopenta-[b]-naphthalene-7-one (15, 17, 21), 3,8-dihydro-5-oxa-1,2,3,8-tetraazacylopenta[b]-naphthalene-7-one (16, 20), 3,8-dihydro-1H-5-oxa-1,3,8-triazacyclopenta[b]-naphthalene-2,7-dione (18, 22), and 5,8-dihydro-4H-1-oxa-4,5,8-triazaanthracene-3,6,7-trione (19). Finally, a chemical library based on 15 was synthesized in parallel solution-phase reactions. 相似文献
20.
Joseph Raker Yi Wang Anthony D. Pechulis James C. Haber Michael A. Lynch Stacey L. Spring 《Journal of heterocyclic chemistry》2012,49(1):221-226
The synthesis and in vitro biological evaluation of two novel benzodiazepine derivatives are described. The compounds were synthesized divergently from the key amino alcohol 5 , which was realized using the unusual Weinreb‐enamino ketone 10 . J. Heterocyclic Chem., (2012). 相似文献