Synthesis and stereochemistry of some new 1,3,5-tris(1,3-dioxan-2-yl)-benzene derivatives

The synthesis and the stereochemistry of new 1,3,5-tris(1,3-dioxan-2-yl)-benzene derivatives are reported. The anancomeric structure and the axial orientation of the aryl group with respect to all 1,3-dioxane rings, and the cis-trans isomerism of some of the compounds are revealed. The data are supported by NMR investigations and by the molecular structure of one compound determined by single crystal X-ray diffractometry.     

Synthesis and stereochemistry of tetrahydroprotoberberine derivatives

A series of 5-hydroxytetrahydroprotoberberines has been prepared from 3-aryltetrahydroisoquinoline derivatives via successive N-alkylation, oxidation and cyclization in acidic media. The relative configurations of the resulting diastereomeric 5-hydroxytetrahydroprotoberberines are reported.     

Synthesis and polymerization of some new biphenyl derivatives

Summary New polymerizable biphenyl derivatives were prepared for the first time: 4-bromo-4-vinylbiphenyl, 4-vinyl-4-biphenylcarboxylic acid, and tributyltin 4-vinyl-4-biphenylcarboxylate.     

Synthesis of some new pyrazoloquinazolinone and quinazolinone derivatives

The benzoxazinone derivative 2‐(6,8‐dibromo‐4‐oxo‐4H‐benzo[d]‐1,3‐oxazin‐2‐yl)‐3‐(4‐methoxyphenyl) acrylonitrile ( 1 ) has been used as a starting material for preparation of the hitherto unknown pyrazoloquinazolinone and quinazolinone derivatives. Under different conditions the benzoxazinone ( 1 ) was reacted with hydrazine hydrate to provide the pyrazolocarbonitrile derivative ( 2 ) and the azine derivative ( 3 ) and/or the pyrazoloquinazoline derivative ( 4 ). When ( 4 ) was conducted to react either with EAA (ethyl acetoacetate) or Ac₂O/AcOH (acetic anhydride/acetic acid) mixture or phthalic anhydride/acetic acid mixture, the pyrazoloquinazoline carbonitrile ( 5 ), pyrazolo‐quinazoline acetic acid ( 6 ) or the pyrazoloquinazolinone derivative ( 7 ) were formed respectively. When ( 1 ) was reacted with phenylhydrazine, a mixture of the quinazolinone derivative ( 8 ) and the hydrazone derivative ( 9 ) were obtained. The benzoxazinone derivative ( 1 ) was found also to react with benzylamine in ethanol or without solvent to give the quinazolinone derivative ( 10 ) or the quinazolindione ( 11 ) respectively. Fusion of ( 1 ) with ammonium acetate yielded the quinazolinone ( 12 ), which was methylated to give ( 13 ) and thiated to the thioxyquinazoline derivative ( 14 ), while reaction of ( 1 ) with formamide gave the N‐formylquinazoline derivative ( 15 ).     

Synthesis of some new pyrimidine selanyl derivatives

The targeted synthesis of 2-(methylsulfanyl)-6-(furan-2-yl)-4(3H)-selenoxo -pyrimidine-5-carbonitrile failed due to the formation 1-methyl-2-methylsulfanyl-6-oxo -4-(furan-2-yl)-1,6-dihydropyrimidine-5-carbonitrile. A new series of 5,6,7,8-tetrahydro-1-benzo thieno[2,3-d]pyrimidine-4-yl substituted selanyl derivatives were prepared by the reaction of sodium diselenide with 4-chloro-5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidine followed by the reaction with chloroacetic acid derivatives such as ethyl chloroacetate, chloroacetamide or chloroacetonitrile. Hydrazinolysis of ethyl (5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidine- 4-ylselanyl)acetate with hydrazine hydrate gave the corresponding hydrazino derivative. The latter reacted with ethyl acetoacetate, acetylacetone, diethyl malonate, ethoxymethylenemalononitrile or ethyl 2-cyano-3-ethoxyacetate to afford 5-methyl-2-[2-(5,6,7,8-tetrahydro-1-benzothieno [2,3-d]pyrimidine-4-ylselanyl)acetyl]-2,4-dihydropyrazol-3-one, 1-(3,5-dimethylpyrazol-1-yl)-2- (5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-4-ylselanyl)ethanone, 1-[2-(5,6,7,8-tetrahydro -1-benzothieno[2,3-d]pyrimidine-4-ylselanyl)acetyl]-2,4-dihydropyrazolidine-3,5-dione and 5-Amino-1-[2-(5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-4-ylselanyl)acetyl]-1H-pyrazol -4-yl substituted carbonitrile or ethyl carboxylate, respectively. The structure of the novel compounds was confirmed by spectroscopic tools (IR, ¹H NMR ¹³C NMR and mass spectra) and elemental analysis.     

Synthesis of some new pyridazino cinnoline derivatives

2,5‐Dibromo‐3,6‐(dihydrazino or diphenylhydrazino)‐1,4‐benzoquinone 1a,b reacts with active methyl‐ene reagents to give some new functionally substituted pyridazino cinnoline derivatives.     

Synthesis of some new fused coumarin derivatives

2-Hydrazino-4-hydroxy-5H- [1] -benzopyrano- [ 4,3-d ] -pyrim-idin-5-one (3) was prepared via condensation of 2 with hy-drazine hydrate. Treatment of 3 with methylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 - ( substituted ) hydrazino - 4 -hydro-xy-5H-[1]-benzopyrano-[4, 3-d]-pyrimidin-5-one (4, 5, 6, and 10), followed by cyclization of 4, 5 and 6 with dimethyl fonnamide and fused sodium acetate under reflux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β-(toloyl) acrylic acid, ethyl α-cyano-p-methoxytinnamate, diethyl mal-onate and acetyl chloride affording the corresponding 2-(substituted) hydrazino-4-hydroxy-5H-[1]-benzopyrano-[4, 3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).     

Synthesis of some new bicyclic pyrazoline derivatives

2,6-Diarylidenecyclohexanones react with hydrazine to give the corresponding bicyclic pyrazolines. The synthesis of a series of twenty eight substituted pyrazolines is described. The structure of all products was confirmed by microanalyses, ir and nmr data.     

The synthesis and stereochemistry of some isatylideneacetic acid derivatives

The preparations of cis- and trans-1-benzylisatylidene-3-acetaldehyde, cis- and trans-1-benzylisatylidene-3-acetic acid and some derivatives are described. Structures are assigned on the basis of NMR and pK_a measurements.     

Synthesis and anticancer activity of some new pyridine derivatives

Different substituents were introduced in positions 2 and 6 of 2,6 diaminopyridine in order to obtain new heterocyclic compounds. A new series of aza pyridine, imidazopyridine, benzodiazepine, indole, pyrimidine, and benzimidazole heterocyclic derivatives were synthesized in good yields. The anticancer activities of some of the new compounds were evaluated against liver cancer cell line HEPG2. Compounds 3, 4, 10, 11, 12, and 17 showed the highest activity when compared to 5-flurouracil (5-FU) and doxorubicin (DOX) chemotherapy.     

Synthesis and reactions of some new allyl furobenzopyranone derivatives

Reaction of visnaginone 1 with allyl bromide gave O‐allyl visnaginone 2 which underwent Claisen rearrangement to yield 7‐allylbenzofuran derivative 3 . Reaction of 3 with different aromatic aldehydes gave the corresponding 5‐cinnamoylbenzofuran derivatives 4a‐d . Condensation of the latter chalcones 4a,c,d with hydrazine hydrate and phenylhydrazine provided, the corresponding pyrazoline derivatives 7a‐f . Claisen condensation of compound 3 with ethyl acetate and diethyl carbonate afforded Claisen adducts 8 and 12 which easily cyclized to 9 and 13 , which are endowed with interesting biological properties.     

Synthesis and biological activity of some new pyridazine derivatives

Summary Condensation of -aroyl--[1,3-diphenyl-5(4H)-oxo-pyrazol-4-yl] propionic acid with hydrazine hydrate affords 4,5-dihydro-3(2H)-pyridazinone (2). Reaction of2 with POCl₃ and P₂S₅ gives a dichloro derivative (7) and a dithione (4). The behavior of the dichloro and dithione derivatives toward various reagents was studied. Thein vitro antibacterial screening reveals moderate activities against certain bacteria.

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Synthese und biologische Aktivität einiger neuer Pyridazinderivate

Zusammenfassung Kondensation von -Aroyl--[1,3-diphenyl-5(4H)-oxo-pyrazol-4-yl]-propionsäure mit Hydrazinhydrat ergibt 4,5-Dihydro-3(2H)-pyridazinon (2). Reaktion von2 mit POCl₃ und P₂S₅ liefert ein Dichlorderivat (7) und ein Dithion (4). Das Verhalten dieser beiden Verbindungen gegenüber verschiedenen Reagentien wurde untersucht. Antibakterielles screening (in vitro) ergab mäßige Aktivität gegenüber verschiedenen Bakterienstämmen.

     

Synthesis of some new biologically active coumarin derivatives

The reaction of 4-hydroxycoumarin in toluene with a variety of aromatic binucleophilic compounds has been studied. 3-(Dimethylaminomethylene)chromane-2,4-dione was used as a key intermediate for the preparation of bis[N-(4-oxocoumarinylmethylene)]-1,4-diamines. Alternative synthetic procedures and antibacterial activity data of some of the new compounds are given. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 361–366, March, 2006.     

The stereochemistry of cleavage of some alkenylmanganese carbonyl derivatives

Cleavage of the compounds trans-RCHCRMn(CO)₅ (where R = CF₃, CO₂Me or CO₂H) with HMn(CO)₅ occurs with complete retention of configuration to yield the corresponding trans-olefins and Mn₂(CO)₁₀. Reaction of the cmpound where R = CF₃ with bromine occurs similarly with retention of configuration to give trans-CF₃CHC(CF₃)Br, whereas cleavage of the compound where R = CO₂H with bromine proceeds with complete inversion of configuration. The compounds cis-MeO₂CCHlCH7z.sbnd;Mn(CO)₅ and trans-MeO₂CCHC(CO₂Me)Mn(CO)₅ react with bromine to give mixtures of cis- and trans-MeO₂CCHCHBr (ratio cis/trans 3/7), and cis- and trans-MeO₂CCHCBrCO₂Me (ratio cis/trans 7/3) respectively.Hydridopentacarbonylmanganese has also been shown to react with MeC₂Me or EtC₂Et to give mainly cis-2-butene and cis-3-hexene respectively, probably by a cis hydride addition followed by stereospecific hydride cleavage. Diphenylacetylene under similar conditions gives trans-stilbene, but as rapid cis/trans isomerisation has also been shown to occur under these conditions, no conclusions regarding the sterochemistry of the hydride addition step could be reached.     

Synthesis and antioxidant properties of some new thiazolyl coumarin derivatives

ABSTRACT

A three-component one-pot synthesis of new thiazolyl coumarin derivatives was carried out by condensing 3-acetyl-4-hydroxycoumarin, arylaldehydes, thiourea and ammonium acetate at reflux in DMC. The optimization details of the developed novel protocol are recorded. In addition, we have also synthesized these compounds via another second route in two steps. High atom-economy, excellent yields, simple procedure, and mild reaction conditions are the important features of this one-pot protocol. The chemical structures of the newly synthesized compounds were elucidated by using analytical (IR, ¹H NMR, ¹³C NMR). Further, all the compounds were screened for their antioxidant activities.     

Synthesis and chemical characterisation of some new diheteroaryl thienothiophene derivatives

Treatment of 1-(5-acetyl-3,4-dimethythieno[2,3-b]thiophene-2yl)ethanone (1) with dimethylformamide dimethyl acetal afforded enaminone derivative 2, which reacted with amino derivatives to give the corresponding bis-pyrimidine, bis-pyrazole, bis-triazolo-pyrimidine and bis-benzoimidazopyrimidine derivatives.     

Synthesis of some new derivatives of dithiene-and oxathienecarboxylic acids

Substituted anilides of 1,4-dithiene- and oxathienecarboxylic acids were synthesized. It was shown that the reaction of 3-phenyl-1,4-dithi-2-ene-2-carboxyl chloride with 2-aminopyridines, depending on the base used and the reaction conditions, leads to the formation of N-[3-phenyl-2-(1,4-dithi-2-en)ylcarbonyl]2-amino-pyridine and/or N,N-bis[3-phenyl-2-(1,4-dithi-2-en)-ylcarbonyl]pyridonimine. The data of IR, UV, and PME spectroscopy were used to confirm the structure of the synthesized compounds.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Science Center, Russian Academy of Sciences. Kazan 420083. Translated fro, Khimiya Geterotskiklicheskikh Soedinenii, No. 9, pp. 1191–1196, September, 1994. Original article submitted May 10, 1994.     

Indole derivatives 138. Synthesis of some new sulfur-containing derivatives of indole

2-Ethoxycarbonyl-5-(p-nitrophenylthio)indole and the corresponding acid were obtained by the E. Fischer reaction. Decarboxylation of the acid gave 5-(p-nitrophenylthio)indole. The geometric isomers of the initial hydrazone of ethyl pyruvate were isolated and characterized.For Communication 137, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1508–1511, November, 1991.