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1.
The reaction of 4-methoxy-5-amino-6-mercaptopyrimidine with 2-oxo-1-chlorocyclopentyl(hexyl)glyoxalate esters gave derivatives of the previously unknown tetracyclic systems 1,2-dioxocyclopenta (hexa)[g]oxazolidino[3,2-f]pyrimido[4,5-b][1,4]thiazines, which are transformed by ammonium acetate into derivatives of 1,2-dioxocyclopenta(hexa) [g]imidazolidino[3,2-f]pyrimido[4,5-b]-[1,4] thiazines. Derivatives of the new tricyclic 1-oxazino [5,4-g]pyrimido[4,5-b][1,4]thiazine system were obrtained by reaction of 6-carbethoxy-7-acetylpyrimido [4,5-b] [1,4] thiazines with hydroxylamine.  相似文献   

2.
Fu R  Xu X  Dang Q  Bai X 《The Journal of organic chemistry》2005,70(26):10810-10816
[reaction: see text] Novel tricyclic pyrimido[4,5-b][1,4]benzothiazepines were readily prepared from 5-amino-4,6-bis(arylthio)pyrimidines and carboxylic acids via Bischler-Napieralski-type reactions. The 6-aryl sulfide group of the resulting pyrimido[4,5-b][1,4]benzothiazepines could be selectively oxidized to its corresponding sulfoxide, which underwent facile substitution reactions when treated with nucleophiles such as an amine. This synthetic strategy provides an efficient way to access a library of novel heterocyclic compounds that are of interest in drug discovery.  相似文献   

3.
We have obtained 5-(2-pyridyl)[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione for the first time by cycloaddition of 2-ethynylpyridine to 4,5-dihydro-1,3-dithioltrithione (isotrithionedithiol). We have studied this thione, 5-(2-pyridyl)- and 5-(4-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thiones by mass spectroscopy and also IR, UV, 1H and 13C NMR spectra. We have determined the crystal and molecular structure of 5-(2-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 429–434, March, 2005.  相似文献   

4.
A newly synthesized donor meso-DMBEDT-TTF [DMBEDT-TTF = 2-(5,6-dihydro-1,3-dithiolo[4,5-b][1,4]dithiin-2-ylidene)-5,6-dihydro-5,6-dimethyl-1,3-dithiolo[4,5-b][1,4]dithiin] afforded a superconducting salt beta-(meso-DMBEDT-TTF)2PF6, with a transition temperature at 4.3 K (onset) under a hydrostatic pressure of 4.0 kbar.  相似文献   

5.
The reaction of 2,3-dibromo-1,4-naphthoquinone with 2-aminothiazole in MeONa/MeOH at 60oC for 3 h gave naphtho[2',3':4,5]imidazo[2,1-b][1,3]thiazole-5,10-dione in 64% yield. The reaction of 2,3-dibromo-1,4-naphthoquinone with 2-aminobenzothiazole under the above-mentioned conditions gave 2-(benzo[d]thiazol-2-ylamino)-3-bromonaphthalene-1,4-dione in 64% yield, which on treatment with Na/THF or NaN3/acetone under reflux conditions gave naphtho[2',3':4,5]imidazo[2,1-b][1,3]- benzothiazole-7,12-dione in 69 and 56% yields, respectively.  相似文献   

6.
4-Chloro-5-amino- and 4-chloro-5-methylamino-6-phenacylmercaptopyrimidines (II–V and XVI–XX) were obtained by the reaction of 4-chloro-5-amino- and 4-chloro-5-methylamino-6-mercaptopyrimidines (I and XV) with phenacyl halides. It is shown that II–V are cyclized by alkalis to 4-chloro-6-aryl-6-hydroxy-5,6-dihydropyrimido[4,5-b][1,4]thiazines (VI–IXa), while both II–IXa and XVI–XIX, respectively, are converted to 7H-4-chloro-6-aryl- (X–XIII) and 5H-4-chloro-5-methyl-6-arylpyrimido[4,5-b][1,4]thiazines (XX–XXIII) under the influence of acidic reagents.See [5] for communication XVIII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 73–77, January, 1971.  相似文献   

7.
《Tetrahedron letters》1987,28(44):5331-5334
2-amino-4-oxo-6-acetyl-3,4,7,8-tetrahydro-3H,9H-pyrimido- [4,5-b][1,4]diazepine (or 6-acetylhomopterin), has been synthesised from 1-amino-4,4-diethoxy-3-pentanol and 2-amino-4-chloro-5-nitro-6(1H)-pyrimidinone.  相似文献   

8.
Reaction of 5-hydroxy-6-aminopyrimidines with 2-bromohydroresorcinol and bromodimedone in DMF in the presence of sodium hydride gave 6,7,8,9-tetrahydro-10H-pyrimido[5,4-b][1,4]benzoxazines. When 4-chloro-5-hydroxy-6-aminopyrimidine was treated with bromodimedone the principal products were 6,7,8,9-tetrahydropyrimido[4,5-b][1,4]benzodioxanes. The nucleophilic substitution of the chlorine atom in position 4 of the tetrahydropyrimidobenzoxazines by amines, sodium alkanoates, and thiourea has been studied and the corresponding amines and alkoxy- and thio derivatives of this tricyclic system obtained. Center for the Chemistry of Medicinal Substances, All Russian Chemico-Pharmaceutical Science Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1411–1417, October, 1998.  相似文献   

9.
The halogenation of 2,3-dimethylpyrazino[2,3-b][1,4]thiazin-6-one with bromine or 1 mole of sulfuryl chloride gives 7-bromo-and 7-chloropyrazino[2,3-b][1,4]thiazin-6-ones, while 2 moles of sulfuryl chloride give 7,7-dichloropyrazino[2,3-b][1,4]thiazin-6-one. A number of 7-amino-and 7,7-diaminopyrazino[2,3-b][1,4]thiazin-6-ones were obtained by the reaction of the appropriate halo derivatives with amines. Some of the pyrazino[2,3-b][1,4]thiazin-6-one derivatives inhibit the growth of interweavable tumors in animals.See [3] for communication XX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1498–1501, November, 1971.  相似文献   

10.

Substituted 6-chloro-pyrimido[4,5-e][1,3,4] thiadiazine was converted to the corresponding 6-hydrazino derivative by treatment with hydrazine hydrate in DMF/Et 3 N. The latter was converted to various substituted [1,2,4]triazino[1,2-a] pyrimido[4,5-e][1,3,4]thiadiazines.  相似文献   

11.
New synthetic pathways to the 5H-pyrido[3',4':4,5]pyrrolo[2,3-b]quinolines 6, the 6H-pyrido[3',4':4,5]pyrrolo[2,3-b][1,6]naphthyridines 7, and the 11H-pyrido[4',3':4,5]pyrrolo[2,3-b]quinolines 8 via thermolysis of the pyridannulated enyne-carbodiimides 14, 19, and 23 were established. These novel heteroaromatic systems are structurally related to ellipticine alkaloids and could serve as DNA-intercalating agents.  相似文献   

12.
It has been shown that 1-aryl-8-(4-bromophenyl)-4,6-dioxo-2H(phenyl)-7-phenyl-1,4,6,7,8,9-hexahydropyrimido[4,5-b][1,6]naphthyridines are formed on heating anilides of 1-aryl-7-(4-bromostyryl)-4-oxo-1,4-dihydropyrido[2,3-d]pyrimidine-6-carboxylic acids in PPA.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, 597–600, April, 2005.  相似文献   

13.
In the present study, the experimentally observed regioselectivity in pyrimido[4,5-b][1,4]benzothiazine synthesis has been modeled using density functional theory method at M06/6-311++G** level. Also the tautomerism of all four tautomers of 6-ethyl-2-thio(1H) pyrimidin-(3H)-4-one as an important intermediate through the reaction path in pyrimido[4,5-b][1,4]benzothiazine synthesis has been investigated extensively in the gas and solution phase. The stability order of tautomers was found as A > D > B > C, in gas and chloroform solvent; however, changing to more polar solvents this order was changed as A > B > D > C using polarized continuum model. In the next step, we focused on another significant feature of this synthesis which has major role in the observed regioselectivity. Two proposed reaction paths with two different transition states that it seems the mode of its intermolecular cyclization has a special role in regioselectivity of the final product have been considered. Comparison of our calculated NMR and IR spectrum with those already reported for some pyrimido[4,5-b][1,4]benzothiazines demonstrates a reliable agreement. Moreover, all obtained results in the gas and solution phase confirm that the synthesis of above-mentioned compound is thermodynamically more favorable than the possible regioisomeric product.  相似文献   

14.
4-Amino-, 4-methylamino-, and 4-dimethylamino-6-aminopyrimido[4,5-b]-1,4-thiazines were obtained. Some of the properties and transformations of 6-aminopyrimido[4,5-b]-1,4-thiazines — their behavior with respect to acids, reductive desulfuration under the influence of Raney nickel, and reaction with hydrazine — were studied.  相似文献   

15.
Cyclization reaction of hydrazine with carbazole-2,3-methyl dicarboxylates gave 1,4-dioxo-1,2,3,4-tetrahydropyridazino[4,5-b]carbazoles. Chlorodehydroxylation provided 1,4-dichloropyridazino[4,5-b]carbazoles and nucleophilic substitution gave 1,4-dialkoxy pyridazino[4,5-b]carbazoles. These compounds were tested for cytotoxic activity against L1210 leukemia in mice.  相似文献   

16.
Abstract

Fragmentation pathways of 14 organophosphorus compounds derived from diethyl spiro[pyrimidino[5,3][1,2]oxazole] phosphonates, diethyl (oxazolo[5,4-d]pyrimidine-4,6-dione)phosphonates, and diethyl (pyrimidino[4,5-b][1,4] oxazine)phosphonates were investigated by electron impact mass spectrometry (EI-MS). The intensity of the recorded molecular ion peaks showed various values depending on the nature of the compounds. Characteristic fragment ions were formed by successive loss of simple functional groups followed by decomposition of heterocycles connected to pyrimidine rings.  相似文献   

17.
An efficient method for the synthesis of novel benzo[b]pyrido[3',2':4,5] thieno[2,3-e][1,6] naphthyridine-8-one derivatives has been developed using a Pictet-Spengler reaction between 4-(3-aminothieno[2,3-b]pyridin-2-yl)quinoline-2-ones, which could be obtained from the alkylation of 4-bromomethylquinoline-2-ones with 3-cyanopyridine-2-thione followed by a Thorpe-Ziegler isomerization, and aromatic aldehydes under p-TsOH as catalysis in good yields.  相似文献   

18.
A new group of 3-substituted-5H-benzo[5,6][1,4]thiazino[3,2-e][1,2,4]triazines was designed, synthesized and evaluated as inhibitors of 15-lipoxygenase (15-LO), and the results were compared with those of standard ligand 4-methyl-2-(4-methylpiperazin-1-yl)pyrimido[4,5-b][1,4]benzothiazine (4-MMPB). Among the newly designed ligands, compound 9e showed the best IC50 of 15-LO inhibition (IC50 = 38 µM). The docking calculations were performed in MOE software based on the function of force-field scoring, in order to study the interaction of these new compounds and standard ligand with 15-LO. The docking study implied that these ligands have hydrogen bond interaction with the residue of active site of 15-LO.  相似文献   

19.
Quantum chemical screening reveals that 4H-dithieno[2,3-b:3',2'-e][1,4]thiazines possess the highest HOMO among four constitutional isomers, even 0.27 eV higher in energy than the well established 10H-phenothiazine. N-Substituted 4H-dithieno[2,3-b:3',2'-e][1,4]thiazines are readily accessible by twofold Pd-catalyzed amination. According to cyclic voltammetry dithienothiazines are reversibly oxidized and can be considered as new donors for functional π-systems.  相似文献   

20.
Fu R  Xu X  Dang Q  Chen F  Bai X 《Organic letters》2007,9(4):571-574
The scope of a sulfur monoxide extrusion reaction of pyrimido[4,5-b][1,4]benzothiazepines leading to pyrimido[5,4-c]isoquinolines was investigated. Thus, selective oxidation followed by nucleophilic displacement of the oxidized side chain sulfur group and subsequent extrusion reaction of sulfur monoxide in the ring, which can be conducted in a two-step sequence or in a one-pot procedure, produced novel pyrimido[5,4-c]isoquinolines, a class of compounds with potential biological and pharmaceutical applications. [reaction: see text].  相似文献   

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