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1.
Treatment of benzyl α-(1) and methyl β- -mannopyranoside (2) with α,α-dimethoxytoluene gave the exo and endo isomers (3,5 and 4,6) of the dibenzylidene derivatives of 1 and 2. Hydrogenolysis of the exo isomers (3 and 5) with a molar equivalent of AlH2Cl gave the 3-0-benzyl-4,6-0-benzylidene derivatives (7 and 21), whereas the endo isomers (4 and 6) gave the 2-0-benzyl-4,6-0-benzylidene compounds (8 and 22). The 2-0-allyl ether 9 of 7, the 3-0-allyl derivative (10) of 8 and compounds 21 and 22 were treated with an additional molar equivalent of AlH2Cl at reflux and the products were the 4-0-benzyl-6-hydroxyl derivatives (11, 12, 23 and 24), whereas in the case of 22 the 6-0-benzyl-4-hydroxyl isomer (25) was also isolated. By deallylation of 11 and 12, 3,4-(13) and 2,4-di-0-benzyl (14) ethers of 1 were prepared. Tosylation of 11 and 12, and subsequent reduction of the products (15 and 16) made possible the preparation of the partially protected benzyl α- -rhamnopyranoside derivatives (17–20). The structures of the compounds synthesized were characterized by 1H and 13C NMR spectroscopic investigation and by chemical methods.  相似文献   

2.
A thermal reaction of indolylmagnesium bromide (5) with 1-cyano-4,5-dimethoxybenzocyclobutene (6) gave a mixture of 6-cyano-5a, 6,11,11a-tetrahydro-8,9-dimethoxy-5H-benzo [b] carbazole (8a) and 6-cyano-5a, 6, 11, 11a-tetrahydro-9-hydroxy-8-methoxy-5H-benzo [b] carbazole (10). Compound 8a was easily converted to 6-cyano-8, 9-dimethoxy-5H-benzo [b] carbazole (12) by dehydrogenation on 30% Pd-C.  相似文献   

3.
Coupling the diazonium salt of 3-amino-2-cyano-4,6-dimethylthieno[2,3-b]pyridine 1 with malononitrile 2 gave 2-cyano-3-(hydrazonomalononitrile)-4,6-dimethylthieno[2,3-b]pyridine 3 which then reacted with hydrazine compounds 4a-4h to yield corresponding 2-cyano-3-(3,5-diamino-1-substituted-pyrazol-4-yl)azo-4,6-dimethylthieno[2,3-b]pyridines 5a-5h. The 2-cyano-3-(2-amino-5,7-disubstituted-pyrazolo-[1,5-a]pyrimidine-3-yl)azo-4,6-dimethylthieno[2,3-b]pyridines 7a-7f were obtained in good yield by the cyclocondensation reaction of 2-cyano-3-(3,5-diamino-pyrazol-4-yl)azo-4,6-dimethylthieno[2,3-b]pyridine 5a with the appropriate 1,3-diketones 6a-6f under acidic condition.  相似文献   

4.
Treatment of benzyl α-(1) and methyl β-d-mannopyranoside (2) with α,α-dimethoxytoluene gave the exo and endo isomers (3,5 and 4,6) of the dibenzylidene derivatives of 1 and 2. Hydrogenolysis of the exo isomers (3 and 5) with a molar equivalent of AlH2Cl gave the 3-0-benzyl-4,6-0-benzylidene derivatives (7 and 21), whereas the endo isomers (4 and 6) gave the 2-0-benzyl-4,6-0-benzylidene compounds (8 and 22). The 2-0-allyl ether 9 of 7, the 3-0-allyl derivative (10) of 8 and compounds 21 and 22 were treated with an additional molar equivalent of AlH2Cl at reflux and the products were the 4-0-benzyl-6-hydroxyl derivatives (11, 12, 23 and 24), whereas in the case of 22 the 6-0-benzyl-4-hydroxyl isomer (25) was also isolated. By deallylation of 11 and 12, 3,4-(13) and 2,4-di-0-benzyl (14) ethers of 1 were prepared. Tosylation of 11 and 12, and subsequent reduction of the products (15 and 16) made possible the preparation of the partially protected benzyl α-d-rhamnopyranoside derivatives (17–20). The structures of the compounds synthesized were characterized by 1H and 13C NMR spectroscopic investigation and by chemical methods.  相似文献   

5.
Convenient and efficient syntheses of ethyl 4-(3-hydroxy-4-methoxyphenyl)-6,7-dimethoxy-2-(1,2,4-triazol-1-ylmethyl)quinoline-3-carboxylate (1d) and 10-(3,4-dimethoxyphenyl)-7,8-dimethoxy-2H-pyridazino[4,5-b]quinolin-1-one (1e), metabolites of TAK-603 (1), have been achieved. Use of the methanesulfonyl as a protective group of the phenolic hydroxy for Friedel-Crafts reaction enabled a new simpler synthetic route of 1d in high yield. Chloromethyl derivative (23) was converted to formyl derivative (32) using the Kröhnke reaction, followed by cyclization with hydrazine, which formed a novel compound 1e.  相似文献   

6.
Reaction of 1-azulenyl methyl sulfoxide (1) under acidic conditions gave the 1,1′-biazulene derivative 3. Methylmercapt groups of 3 were readily converted to formyl groups by Vilsmeier reaction to afford 3,3′-diformyl-1,1′-biazulene (4), which reacted with pyrrole in the presence of acetic acid to give the parent 1,1′-biazulene (5). Reaction of 5 with pyridine in the presence of Tf2O gave 3,3′-dihydropyridyl-1,1′-biazulene derivative 6. 3,3′-(4-Pyridyl)-1,1′-biazulene (7) was obtained by the reaction of 3 with KOH in EtOH at room temperature in good yield.  相似文献   

7.
Summary 3-Carbethoxy-4,6-diphenyl-2-pyrridine sulfonamide (5), can be cyclized to 3-oxo-2,3-dihydro-4,6-diphenylisothiazolo[5,4-b]pyridine-1,1-dioxide (2). Oxidation of pyridinethione6 with Cl2/H2O gave the sulfonyl chloride derivative7, which can be ammonolyzed to 3-amino-4,6-diphenylisothiazolo[5,4-b]pyridine-1,1-dioxide (8), and 3-cyano-4,6-diphenylpyridine-2-sulfonamide (9). Hydrolysis of6 gave 3-carboxamido-2(1H)pyridinethione (12) which can be oxidized with iodine to 3-oxo-4,6-diphenyl-2,3-dihydroisothiazolo[5,4-b]pyridine (13). 3-Methyl-4,6-diphenylisothiazolo[5,4-b]pyridine-1,1-dioxide (17) was also prepared from6.
Heterocyclensynthese mit 3-Cyano-2(1H)pyridinthion: Synthese von 3-Oxo-2,3-dihydroisothiazolo-[5,4-b]pyridin und verwandten Verbindungen
Zusammenfassung 3-Carbethoxy-4,6-diphenyl-2-pyridinsulfonamid (5) kann zu 3-Oxo-2,3-dihydro-4,6-diphenylisothiazolo[5,4-b]pyridin-1,1-dioxid (2) cyclisiert werden. Die Oxidation des Pyridinthions6 mit Cl2/H2O ergab das Sulfonylchlorid-Derivat7, das mit Ammoniak zu 3-Amino-4,6-diphenylisothiazolo[5,4-b]pyridin-1,1-dioxid (8) und 3-Cyano-4,6-diphenylpyridin-2-sulfonamid (9) umgesetzt werden kann. Die Hydrolyse von6 ergab 3-Carboxamido-2(1H)pyridinthion (12), das mit Jod zu 3-Oxo-4,6-diphenyl-2,3-dihydroisothiazolo[5,4-b]pyridin (13) oxidiert wurde. 3-Methyl-4,6-diphenyl-isothiazolo[5,4-b]pyridin-1,1-dioxid (17) wurde ebenfalls aus6 hergestellt.
  相似文献   

8.
Novel 3-(4,6-dimethoxybenzofuran-5-yl)-1-phenyl-1H-pyrazole-4-carboxaldehyde (3) and 3-chloro-3-(4,6-dimethoxybenzofuran-5-yl)propenal (4) were prepared via Vilsmeier–Haack reaction of 1-(4,6-dimethoxybenzofuran-5-yl)ethanone (1) and its hydrazone derivative 2. Reaction of compound 4 with some hydrazine derivatives, namely hydrazine hydrate, phenylhydrazine and benzylhydrazine hydrochloride led to the formation of pyrazole derivatives 58, respectively. On the other hand, reaction of compound 4 with thiourea, urea or guanidine gave the pyrimidine derivatives 911, respectively. Reaction of amino compound 11 with acetic anhydride, benzoyl chloride and benzenesulphonyl chloride yielded N-substituted pyrimidine derivatives 12–14, respectively. Reaction of diazonium salt of compound 11 with sodium azide afforded azidopyrimidine derivative 15, which upon reaction with ethyl acetoacetate gave 1,2,3-triazole derivative 16. Acid catalyzed reaction of 11 with p-nitrobenzaldehyde gave Schiff base 17, which cyclized upon reaction with thioglycolic acid or chloroacetyl chloride to give thiazolidin-4-one 18 and azetidin-2-one 19, respectively. The newly synthesized compounds were tested for their anti-inflammatory, analgesic and anticonvulsant activities. Depending on the obtained results, the newly synthesized compounds possess significant anti-inflammatory, analgesic and anticonvulsant activities.  相似文献   

9.
The chromophore 2-(3-cyano-4-((2-(4,6-dimethyl-5-nitro-1H-pyrazolo[3,4-b]pyridin-3-yl) hydrazono)methyl)-5,5-dimethylfuran-2(5H)-ylidene)malononitrile (PPHTCF) was synthesized through coupling of diazotized 3-amino-4,6-dimethyl-5-nitropyrazolo[3,4-b]pyridine with 3-cyano-2-(dicyanomethylene)-4,5,5-trimethylfuran (TCF). The absorption solvatochromism behaviour of PPHTCF, in various solvents, presented ΔEmax = +5.40 where the positive sign suggested red shift occurrence, implying that the PPHTCF has more polar lowest excited state than its ground one. While, the PPHTCF fluorescence spectra afforded λem, in 575–633 nm range, and was more dependent on the solvent polarity than the absorption λmax, despite both exhibited red shift by 58 and 42 nm, respectively. To discover the PPHTCF solvatochromism behaviour in term of “Stokes’ shift”, both of Lippert-Mataga and linear solvation-energy relationship (LSER) formulations have been utilized and the outcomes endorsed that the later was better than the former (R2 = 0.9728). Finally, TD-DFT simulated absorption and emission spectra in EtOH revealed that λmax has been resulted mainly from HOMO → LUMO; HOMO-5 → LUMO and HOMO-2 → LUMO transitions, respectively.  相似文献   

10.
Several 3-amantadinyl-2-[(2-substituted benzylidenehydrazinyl)methyl]-quinazolin-4(3H)-ones (5a5l) were prepared by the reaction of 3-amantadinyl-2-hydrazinylmethyl substituted quinazolin-4(3H)-ones (4a4b) with various substituted aromatic aldehydes. Cycloaddition of compounds (5a5l) with thioglycolic acid in the presence of anhydrous zinc chloride yielded 3-amantadinyl-2-[((substitutedphenyl)-4-oxo-thiazolidin-3-yl)methylamino]-quinazolin-4(3H)-ones (6a6l). Compounds 5a5l on further reaction with chloro acetyl chloride in the presence of triethylamine gave 3-amantadinyl-2-[((substitutedphenyl)-3-chloro-2-oxo-azetidin-1-yl)methylamino]-quinazolin-4(3H)-ones (7a7l). The compounds 5a5l, 6a6l and 7a7l were screened for their antiparkinsonian activity. The most active compound was 6g i.e. 3-amantadinyl-6-bromo-2-[((3,4-dimethoxyphenyl)-4-oxo-thiazolidin-3-yl)methylamino]-quinazolin-4(3H)-ones. Structures of the newly synthesized compounds were established on the basis of elemental and spectral (IR, 1H NMR and mass) analysis.  相似文献   

11.
M.Helmy Elnagdi 《Tetrahedron》1974,30(16):2791-2796
Malononitrile (1) reacts with β-cyanoethylhydrazine (2) to yield 5-amino-4-cyano-1-β-cyanoethyl-3-cyanomethyl-pyrazole (3). Treatment of 3 with 1% NaOH solution results in the formation of 3-cyano-2-cyanomethyl-4,5,6,7-tetrahydropyrazolo[1.5-a] pyrimine (6). On the other hand, when 3 was refluxed with acetic acid-hydrochloric acid mixture, the pyrido[3:4:3′:4′]pyrazolo[1.5-a] pyrimidine (10) was formed.1,2-Dihydro-5-hydroxy-3-phenylazopyrazolo[1.5-a] pyrimidine (16) was obtained by cyclization of 3,5-dianimo-1-(β-cyanoethyl)-4-phenylazopyrazole (18), which, in turn, was obtained by the action of 2 on phenylazomalononitrile (17).Ethoxymethylenemalononitrile (20) reacts with 2 to yield 3-amino-4-cyano-1-β-cyanoethyl)-pyrazole (21). Compound 21 was readily cyclized into the pyrrolo[1.2-b]pyrazole derivative 25 by the action of either 3% NaOH solution or conc sulphuric acid.  相似文献   

12.
Hauser annulation of 3-cyano-5,7-dimethoxy-(3H)-isobenzofuran-1-one 4 with ethyl acrylate as a method to access activated naphthoquinone 3, a key intermediate for the synthesis of thysanone 1, proved unreliable. In contrast to this, Hauser annulation of regioisomeric 3-cyano-4,6-dimethoxy-(3H)-isobenzofuran-1-one 13 with ethyl acrylate proceeded readily affording ethyl 5,7-dimethoxy-1,4-naphthoquinone 12, after oxidation of the initial dihydroxynaphthalene 16. Allylation of naphthoquinone 12 followed by reductive methylation and Wacker oxidation afforded ketone 11 that underwent CBS reduction to (2′S)-alcohol 19 followed by cyclisation to lactone 20. Reduction of the lactone followed by oxidative demethylation afforded (1S,3S)-6,8-dimethoxy-1-hydroxy-3-methylpyrano[2,3-c]-1,4-naphthoquinone 22, a regioisomeric analogue of the 3C-protease inhibitor thysanone 1.  相似文献   

13.
Mercury(II)-mediated ring closure of N-[1-(2-allyl-3-benzyloxy-4,6-dimethoxyphenyl)ethyl]acetamide 9 afforded N-acetyl-5-benzyloxy-6,8-dimethoxy-1,3-trans-dimethyl-1,2,3,4-tetrahydroisoquinoline 8. The product was shown to exist as a mixture of amide rotamers by NMR spectroscopy, since signals coalesced at higher temperatures. Variable temperature NMR spectroscopy and molecular modelling were used to investigate these rotamers and gave average values for the barrier of rotation in the range of 15-16 kcal mol−1. 2-[2-[1-(Acetylamino)ethyl]-6-(benzyloxy)-3,5-dimethoxyphenyl]-1-methylethyl methanesulfonate 17 was also cyclized with sodium hydride to afford the same rotameric products with the same tetrahydroisoquinoline skeleton, but as a mixture of 1,3-trans- and cis-dimethyl isomers.  相似文献   

14.
3-Bromo-3-cyanosuccinimides 1 and 3,5-dibromo-3,5-dicyanoglutarimides 17 react with P(OPh)3, Ph2POPh and PhP(OPh)2 to yield quasiphosphonium salts. The glutarimide adducts were transformed rapidly into 2,6-dibromo-3,5-dicyano-1,4-dihydropyridines 22. 3-Bromo-3-cyano-1-methylsuccinimide and P(OPh3) yields an oxazaphosphorane 6. An equilibrium exists between oxazaphosphoranes and iminophosphoranes for adducts formed from succinimides and PhP(OPh)2 or Ph2P(OPh).  相似文献   

15.
Malononitrile reacted with the title compound to give 6-amino-5-cyano-2-(3,3-dicyano-2-methylallylidene-4-methyl-2H-pyran (3). Treatment of 3 with hot 80% sulfuric acid yielded 4,7-dimethyl-56-hydroxy-2(1H)quinolone. With concentrated aqueous sodium hydroxide, 3 gave 5-amino-3,6-dicyano-4,7-dimethyl-2(1H)quinolone and 5-amino-6-carbamoyl-3-cyano-4,7-dimethyl-2(1H)quinolone. The reaction of 3 with hydrochloric in acetic acid gave a mixture of 6-amino-3,7-dicyano-2,8-dimethyl-4-quinolizone and 3-cyano-4-methyl-6-(3,3-dicyano-2-methylallyl)-2-pyrone. Compound 3 also reacted with methylamine, butylamine and piperidine to give 8-amino-5-cyano-4-methyl-2-pyridone, 6-bulylamino-5-cyano-4-methyl-2-pyridone and 5-eyano-4-methyl-6-piperidino-2-pyridone respectively.  相似文献   

16.
Stereoselective diazotization of (S)-2-amino-2-phenyl acetic acid (L-phenyl glycine) (4) with NaNO2 in 6% H2SO4 in a mixture of acetone and water gave optically pure (S)-2-hydroxy-2-phenyl acetic acid (L-mandelic acid) (5). Esterification, gave (S)-2-hydroxy-2-phenyl acetic acid esters (6). The latter was treated with chloroacetyl chloride in the presence of triethylamine (TEA) in dichloromethane (DCM) to yield (S)-2-chloroacetyloxy phenyl acetic acid ester (2). In another sequence, the reaction of 2-(chloromethyl)-3-arylquinazolin-4(3H)-one (9) treated with N-Boc piperazine, followed by deprotection of the Boc group, to obtain 3-aryl-2-((piperazin-1-yl)methyl) quinazolin-4(3H)-one (3). Reaction of 2 with 3 in the presence of K2CO3 and KI gave the title compound, 2-(2-(4-((3,4-dihydro-4-oxo-3-arylquinazolin-2-yl)methyl)piperazin-1-yl) acetoyloxy)-2-phenyl acetic acid esters (1). The structures of all the new compounds obtained in the present work are supported by spectral and analytical data.  相似文献   

17.
F. Cech  E. Zbiral 《Tetrahedron》1975,31(6):605-612
IR-spectroscopic measurements between ?60° and 0°C show the existence of C6H5J(OAc)2-n(N3)n generated by the reaction of C6H5J(OAc)2 with (CH3)3SiN3. C6H5J(OAc)2-n(N3)n reacts with 2,3-dimethylbutad to give substances C12H20N6 (1), having the probable structure of 2,3,5-trimethyl-3,6-di-azidomethyl-heptadiene-1,5 and 3,4-diazido-3-methylbutanone-2 (2). Likewise we get from 1,3-cyclohexadiene the diazide C12H16N6 (3), and 4-azido-cyclohexene-2-on-1 (4). Analogously from cyclopentadiene we get the carbonylcompound 4-azido-cyclopentene-2-on-1 (5). E-5-azido-hexene-3-on (8) results from 2,4-E,Z-hexadiene. 1,3-cyclooctadiene gives as main product 6 (4-azido-cyclooctene-2-on-1) but also some 7 (8-azido-cyclooctene-2-on-1) emerging from an attack on positions 1 and 2.Δ1,3, Δ3,5 and Δ4,6-cholestadiene yield in a regio- and stereo-specific manner the products 9 (1α-azidocholestene-2-on-4), 10 (6β-azidocholestene-4-on-3) and 11 (4β-azidocholestene-5-on-7). These last examples confirm our suggestions from the preponderance of the 1,4-functionalisation.  相似文献   

18.
Stereoselective alkylation of the anion derived from (2R)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine with 2-chloromethylbenzothiophene afforded the corresponding trans-monosubstituted product, (2S,5R)-2-((1-benzo[b]thiophen-2-yl)methyl)-3,6-dimethoxy-5-(propan-2-yl)-2,5-dihyropyrazine in 88% yield. Hydrolysis of the alkylated product using 40% TFA/H2O at 0?°C and subsequent protection of the α-amino functional group with Fmoc-OSu afforded Fmoc-l-3-(2-benzothienyl)alanine methyl ester in 88% yield. Hydrolysis of the methyl ester with aqueous LiOH gave Fmoc-l-3-(2-benzothienyl)alanine in 62% overall yield.  相似文献   

19.
Nickel complexes prepared using a 4-(2,6-diisopropylphenylimino)-3,3-dimethylpentan-2-one ligand framework are shown. The potassium salt of the ligand is obtained by deprotonation with KH in diethyl ether. Potassium 4-(2,6-diisopropylphenylimino)-3,3-dimethyl-pent-2-en-2-olate can then be reacted with Ni(PMe3)21-CH2Ph)Cl to yield 4-(2,6-diisopropylphenylimino)-3,3-dimethyl-pent-2-en-2-olato-κ1O](η1-CH2Ph)(PMe3)2Ni (1). The potassium salt of the ligand can also be reacted with Ni(PMe3)(η3-CH2Ph)Cl to yield bis(4-(2,6-diisopropylphenylimino)-3,3-dimethyl-pent-2-en-2-olato-κ2N,O](η1-CH2Ph)2Ni2 (2) or 4-(2,6-diisopropylphenylimino)-3,3-dimethyl-pent-2-en-2-olato-κ2N,O](η1-CH2Ph)(PMe3)Ni (3), depending on the reaction conditions. The addition of five equivalents of B(C6F5)3 to 1, 2, or 3 yields catalytically active species for the homopolymerization of ethylene. The polymer products are described by a single molecular weight distribution, consistent with the presence of a single active site.  相似文献   

20.
J.R. Bull  J. Floor  A. Tuinman 《Tetrahedron》1975,31(17):2157-2162
The reaction of 3,3-ethylenedioxy-9-methyl-9β-oestr-5(10)-en-17-one (4) with tosylmethyl isocyanide and base afforded the 17β- and 17α-carbonitriles (5 and 6). Treatment of the 17β-epimer (5) with methyl lithium gave, after hydrolysis, 9-methyl-19-nor-9β-pregn-5(10)-ene-3,20-dione (8). The same reaction sequence employed on 3,3; 5,5-bisethylenedioxy-9-methyl-4,5-seco-9β,10α-oestr-17-one (12), with subsequent cyclization, yielded the 5β-hydroxy-3,20-diketones (17 and 18) as well as 9-methyl-19-nor-9β,10α-progesterone (19) and its 17α-epimer (20).  相似文献   

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