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1.
Through ring-closure reactions of N- or 1′-substituted 1-(2′-aminoethyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines (5a-e) with phenylphosphonyl dichloride, 1- or 3-substituted 4-phenyl-1,3,4,6,7,11b-tetrahydro-2H-1,3,2-diazaphosphorino[6,1-a]isoquinolin-4-one diastereomers (7a-e and 8a-c,e), the first representatives of a new ring system, were prepared. The diastereomeric ratios in the cyclizations and the conformer (A-E) populations of the nitrogen-bridged tricyclic systems (7 and 8) were strongly influenced by the N- and 1′-substituents of the starting diamines. The conformational analysis of compounds 7 and 8 was performed by 1H, 13C and 31P NMR methods.  相似文献   

2.
N,N,N′,N′-Tetramethylmethanediamine (1a), N,N,N′,N′-tetramethylethanediamine (1b), N,N,N′,N′-tetramethyl-1,3-propanediamine (1c), and N,N,N′,N′-tetramethyl-1,6-hexanediamine (1d) were reacted at 25 °C with 1,1,1,5,5,5-hexafluoro-2,4-pentanedione (2a), 2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedione (2b), 2-thenoyltrifluoroacetone (2c), and 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione (2d) to form the ionic adducts 3-18. 1,4,7,10-Tetraazacyclododecane (1e) reacted at 25 °C with β-diketones (2a-d) and 1,1,1-trifluoro-2,4-pentanedione (2e) to give ionic solids 19-23 in good yields. Some of the products are liquid at 25 °C and are thermally stable over long liquid ranges as determined by thermal gravimetric analyses. Single-crystal X-ray structure determinations show that compounds 9 and 21 crystallize in the monoclinic space groups P2(1)/c and P2(1)/n, respectively. All the new compounds were characterized by 1H, 19F and 13C NMR, electrospray MS and/or elemental analyses.  相似文献   

3.
Novel condensation reaction of tropone with N-substituted and N,N′-disubstitued barbituric acids in Ac2O afforded 5-(cyclohepta-2′,4′,6′-trienylidene)pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (8a-f) in moderate to good yields. The 13C NMR spectral study of 8a-f revealed that the contribution of zwitterionic resonance structures is less important as compared with that of 8,8-dicyanoheptafulvene. The rotational barriers (ΔG) around the exocyclic double bond of mono-substituted derivatives 8a-c were obtained to be 14.51-15.03 kcal mol−1 by the variable temperature 1H NMR measurements. The electrochemical properties of 8a-f were also studied by CV measurement. Upon treatment with DDQ, 8a-c underwent oxidative cyclization to give two products, 7 and 9-substituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborates (11a-c·BF4 and 12a-c·BF4) in various ratios, while that of disubstituted derivatives 8d-f afforded 7,9-disubstituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborate (11d-f·BF4) in good yields. Similarly, preparation of known 5-(1′-oxocycloheptatrien-2′-yl)-pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (14a-d) and novel derivatives 14e,f was carried out. Treatment of 14a-c with aq. HBF4/Ac2O afforded two kinds of novel products 11a-c·BF4 and 12a,c·BF4 in various ratios, respectively, while that of 14d-f afforded 11d-f. The product ratios of 11a-c·BF4 and 12a-c·BF4 observed in two kinds of cyclization reactions were rationalized on the basis of MO calculations of model compounds 20a and 21a. The spectroscopic and electrochemical properties of 11a-f·BF4 and 12a-c·BF4 were studied, and structural characterization of 11c·BF4 based on the X-ray crystal analysis and MO calculation was also performed.  相似文献   

4.
The reactions of organoantimony chlorides L1,2SbCl21 and 2 ([2,6-(ROCH2)2C6H3], R = Me; L1 and R = t-Bu; L2) with silver salts of selected carboxylic acids resulted to corresponding organoantimony carboxylates L1,2Sb(OOCR′)2, 1a-c (for L1) and 2a-c (for L2), where R′ = CH3 for 1a, 2a; R′ = CHCH2 for 1b, 2b and R′ = CF3 for 1c, 2c. All compounds were characterized by the help of elemental analysis, ESI-MS, 1H and 13C NMR spectroscopy. The solid state structure investigation using single crystal X-ray diffraction techniques (2a, c) and IR spectroscopy revealed significant differences in coordination mode of both O,C,O chelating ligand and carboxylic groups in this set of compounds. The structure of all compounds in solution of non-coordinating solvent (CDCl3) was determined by means of variable temperature 1H, 13C, 19F NMR spectroscopy and IR spectroscopy.  相似文献   

5.
Three new compounds of aryl thiourea derivatives, namely N-2-(4-picolyl)-N′-(4-methoxyphenyl)thiourea (L1), N-2-(6-picolyl)-N′-(4-methoxyphenyl)thiourea (L2) and N-2-(4-picolyl)-N′-(4-nitrophenyl)thiourea (L3), and the new copper(II) complex [Cu(4PicTz4OMePh)(OAC)(EtOH)] (C1), as a result of oxidative cyclization of the ligand (L1), were synthesized. In addition, pure precursor (P1), as the product of the oxidative cyclization of N-(2-pyridyl)-N′-(4-methoxyphenyl)thiourea (L4), was isolated and characterized. Ligands (L1) and (L2) were characterized by 1H and 13C NMR and single crystal X-ray analysis. 1H NMR spectroscopy showed strong hydrogen bonding interactions between N′H-functionalities and the pyridine nitrogen atoms as well as weak intermolecular hydrogen bonding between the thione sulfur and the NH hydrogen. Structural studies of complex (C1) showed that the copper ion is five-coordinated with a square-pyramidal environment. The oxidative cyclization of ligand (L1) results in an anionic bidentate ligand in complex (C1). Both ligand (L1) and precursor (P1) crystallize as centrosymmetric dimers.  相似文献   

6.
Eight new compounds including 9′-[2-amino-3-(4″-O-methyl-α-rhamnopyranosyloxy) phenyl]nonanoic acid (1), 9′-[2-amino-3-(4″-O-methyl-α-ribopyranosyloxy)phenyl] nonanoic acid (2), 11′-[2-amino-3-(4″-O-methyl-α-rhamnopyranosyloxy)phenyl]undecanoic acid (3), 11′-[2-amino-3-(4″-O-methyl-α-ribopyranosyloxy)phenyl]undecanoic acid (4), 8-(4′-O-methyl-α-rhamnopyranosyloxy)-3,4-dihydroquinolin-2(1H)-one (5), 8-(4′-O-methyl-α-ribopyranosyloxy)-3,4-dihydroquinolin-2(1H)-one (6), 8-(4′-O-methyl-α-rhamnopyranosyloxy)-2-methyquinoline (7), and 8-(4′-O-methyl-α-ribopyranosyloxy)-2-methylquinoline (8) were isolated from Actinomadura sp. BCC27169. The chemical structures of these compounds were determined based on NMR and high-resolution mass spectroscopy. The absolute configurations of these monosaccharides were revealed by the hydrolysis of compounds 7 and 8. Compounds 3 and 8 exhibited antitubercular activity at MIC 50 μg/mL. Only compound 3 showed cytotoxicity against KB cell at IC50 18.63 μg/mL, while other isolated compounds were inactive at tested maximum concentration (50 μg/mL).  相似文献   

7.
Shin-ichi Naya 《Tetrahedron》2008,64(14):3225-3231
As novel methodology for synthesizing the furan ring, a photoinduced oxidative cyclization of 5-(4′,9′-methanocycloundeca-2′,4′,6′,8′,10′-pentaenylidene)pyrimidine-2,4,6(1,3,5H)-triones (7a-c) and related compounds 9a-c was accomplished to give 5,10-methanocycloundeca[4,5]furo[2,3-d]pyrimidine-2,4(1,3H)-dionylium tetrafluoroborates (8a-c+·BF4) and related compounds 2a-c+·BF4, respectively. In the photoinduced oxidative cyclization, the molecular oxygen in air is used as oxidant and the reaction proceeds under mild conditions to give desired products without byproducts, and thus, it is interesting from the viewpoint of the green chemistry. On the reactions of the mono-substituted derivatives 7d,e and 9e,f, the selectivity of the photoinduced cyclizations were reversed as compared with those of the DDQ-promoted oxidative cyclizations. By the NMR monitoring of the reactions of 7a and deuterated compound 7a-D2 under degassed conditions, the details of the reaction pathway were clarified and rationalized on the basis of the MO calculation by the 6-31G basis set of the MP2 levels as well.  相似文献   

8.
A series of benzyloxybenzaldehyde derivatives (1-4) were synthesized by the reactions of 4-(bromomethyl)benzonitrile with 4-hydroxy-3-methoxybenzaldehyde (vanillin), 2-hydroxy-3-methoxybenzaldehyde (o-vanillin), 2-hydroxy-4-methoxybenzaldehyde and 2-hydroxy-5-methoxybenzaldehyde. Condensation reactions among the new benzyloxybenzaldehyde derivatives (1-4) with 4′-aminobenzo-15-crown-5 yielded the new Schiff base compounds (5-8). Sodium complexes (5a-8a) and potassium complexes (5b-8b) were prepared with NaClO4 and KI, respectively. All of these synthesized compounds were characterized on the basis of FT-IR, 1H and 13C NMR, mass spectrometry and elemental analyses data. The solid state structures of compounds 8 and 5a were determined by X-ray crystallography. The extraction abilities of compounds 5-8 were also evaluated in CH2Cl2 by using several main group and transition metal picrates, such as Na+, K+, Pb2+, Cr3+, Ni2+, Cu2+ and Zn2+.  相似文献   

9.
N,N-dicyclohexyl-N-ferrocenoylurea 2, N,N-diisopropyl-N-ferrocenoylurea 3, N,N-di-p-tolyl-N-ferrocenoylurea 4 and N,N-di-tert-butyl-N-ferrocenoylurea 5 were obtained by reaction of ferrocenecarboxylic acid 1 with N,N-dicyclohexylcarbodiimide (DCC), N,N-diisopropylcarbodiimide (DIC), N,N-di-p-tolylcarbodiimide 10 and N,N-di-tert-butylcarbodiimide 11, respectively. Both N-tert-butyl-N-ethyl-N-ferrocenoylurea 6 and N-tert-butyl-N-ethyl-N-ferrocenoylurea 7 were obtained by reaction of 1 with N-tert-butyl-N-ethylcarbodiimide 12. In all cases a small amount of ferrocenecarboxylic anhydride 8 was formed as a by-product. All compounds were characterized by 1H NMR, 13C NMR, IR and MS. Single crystal X-ray structural analyses were made of 2, 3 and 4. From the consistent results, the reaction products of 1 with carbodiimides appear different from those proposed by some earlier workers. With N-(3-dimethylaminopropyl)-N-ethylcarbodiimidehydrochloride 9 ferrocenoylurea was not isolated, but the main product was rather 8. The suitability of 8 as acylation reagent was applied by using 9 to obtain N-(3-triethoxysilyl)-propylferrocenecarboxamide in a one-pot reaction from 1 and 3-(triethoxysilyl)-propylamine.  相似文献   

10.
Three optically active binuclear diorganotin compounds (2-4) were prepared from an optically active oxalamide: (1S,2R)-(−)-[N-(2-hydroxy-1-methyl-2-phenyl-ethyl)-N′-(2-hydroxy-phenyl)-oxalamide (1). The new compounds [1-(2′,2′-diorganyl-1′-oxa-3′-aza-2′-stanna-indan-3′-yl)-2-(2″,2″-diorganyl-4″-methyl-5″-phenyl[1,3,2]-oxazastannolidin-3″-yl)-ethane-1,2-dione {organyl = methyl (2), n-butyl (3) or phenyl (4)} were characterized by IR, elemental analysis and mass spectrometry. Compounds 3 and 4 were submitted to a detailed NMR study in order to assign their resonances (1H and 13C) and specially the two different 119Sn signals for each compound. The X-ray diffraction analysis of compound 4 showed a planar pentacyclic framework with two penta-coordinated tin atoms with a distorted tbp geometry and 12 intramolecular hydrogen bonds.  相似文献   

11.
2,3-Diferrocenyl-1-methylthiocyclopropenylium iodide reacts with water, metal alkoxides, phenolates and with alcohols in the presence of Et3N to give E-1,2-diferrocenyl-3-methylthioprop-2-enone or its ketals. Their structures were established based on data from 1H and 13C NMR spectroscopy and X-ray diffraction analysis. The mechanistic aspects of these reactions are discussed. Electrochemical properties of 8 and 13b have been studied. The compounds present two oxidation processes (I-II), attributed to the oxidations of the ferrocenes groups, E0′(I), E0′(II), ΔE0′(II-I) and comproportionation constant Kcom are reported.  相似文献   

12.
The reactions of the trimethylsiloxychlorosilanes (Me3SiO)RR′SiCl (1a-h: R′ = Ph, 1a: R = H, 1b: R = Me, 1c: R = Et, 1d: R = iPr, 1e: R = tBu, 1f: R = Ph, 1g: R = 2,4,6-Me3C6H2 (Mes), 1h: R = 2,4,6-(Me2CH)3C6H2 (Tip); 1i: R = R′ = Mes) with lithium metal in tetrahydrofuran (THF) at −78 °C and in a mixture of THF/diethyl ether/n-pentane in a volume ratio 4:1:1 at −110 °C lead to mixtures of numerous compounds. Dependent on the substituents silyllithium derivatives (Me3SiO)RR′SiLi (2b-i), Me3SiO(RR′Si)2Li (3a-g), Me3SiRR′SiLi (4a-h), (LiO)RR′SiLi (12e, 12g-i), trisiloxanes (Me3SiO)2SiRR′ (5a-i) and trimethylsiloxydisilanes (6f, 6h, 6i) are formed. All silyllithium compounds were trapped with Me3SiCl or HMe2SiCl resulting in the following products: (Me3SiO)RR′SiSiMe2R″ (6b-i: R″ = Me, 7c-i: R″ = H), Me3SiO(RR′Si)2SiMe2R″ (8a-g: R″ = Me, 9a-g: R″ = H), Me3SiRR′SiSiMe2R″ (10a-h: R″ = Me, 11a-h: R″ = H) and (HMe2SiO)RR′SiSiMe2H (13e, 13g-i). The stability of trimethylsiloxysilyllithiums 2 depends on the substituents and on the temperature. (Me3SiO)Mes2SiLi (2i) is the most stable compound due to the high steric shielding of the silicon centre. The trimethylsiloxysilyllithiums 2a-g undergo partially self-condensation to afford the corresponding trimethylsiloxydisilanyllithiums Me3SiO(RR′Si)2Li (3a-g). (Me3)Si-O bond cleavage was observed for 2e and 2g-i. The relatively stable trimethylsiloxysilyllithiums 2f, 2g and 2i react with n-butyllithium under nucleophilic butylation to give the n-butyl-substituted silyllithiums nBuRR′SiLi (15g, 15f, 15i), which were trapped with Me3SiCl. By reaction of 2g and 2i with 2,3-dimethylbuta-1,3-diene the corresponding 1,1-diarylsilacyclopentenes 17g and 17i are obtained.X-ray studies of 17g revealed a folded silacyclopentene ring with the silicon atom located 0.5 Å above the mean plane formed by the four carbon ring atoms.  相似文献   

13.
Reinvestigation of the secondary metabolites from the marine mangrove fungus Aigialus parvus BCC 5311 led to the isolation of six new nonaketide metabolites, aigialomycins F (4) and G (5a/5b), 7′,8′-dihydroaigialospirol (7), 4′-deoxy-7′,8′-dihydroaigialospirol (8), and rearranged macrolides 9 and 10, along with six previously described compounds, hypothemycin (1), aigialomycins A (2) and B (3), aigialospirol (6), 4-O-demethylhypothemycin (11), and aigialone (12). The structures of the new compounds were elucidated by analyses of the NMR spectroscopic and mass spectrometry data in combination with chemical means.  相似文献   

14.
Four stereoisomers of nodulisporacid A (1) were synthesized by the concise approach which includes three-component reaction and subsequent one-pot construction of the whole framework. The 1H NMR comparison of the derivatives (10-12) revealed the absolute configuration of natural 1 to be 4R,4′R,6′R.  相似文献   

15.
Several novel trans-3-benzyl/(diphenyl)methyl/naphthylseleno substituted monocyclic β-lactams (5-7) have been synthesized in high yields. The reaction scheme inolves [2 + 2] cycloaddition (Staudinger) reaction between suitably substituted imines 4(a-h) and ketenes (B) accessed from 2-benzyl/(diphenyl)methyl/naphthylselenoethanoic acids (1-3) using POCl3 and triethylamine in refluxing toluene. Characterization of these newly synthesized seleno substituted β-lactams has been performed by various spectroscopic techniques viz. NMR (1H, 13C and 77Se), FTIR, mass spectrometry and elemental analysis. The molecular structure of trans-1-(4′-methoxyphenyl)-3-(diphenyl)methylseleno-4-(4′-methoxyphenyl)azetidin-2-one (6b) has also been established with the help of single crystal X-ray analysis.  相似文献   

16.
Shin-ichi Naya 《Tetrahedron》2005,61(31):7384-7391
The synthesis and properties of 4,9-methanoundecafulvene [5-(4,9-methanocycloundeca-2′,4′,6′,8′,10′-pentaenylidene)pyrimidine-2,4,6(1,3,5H)-trione] derivatives 8a,b were studied. Their structural characteristics were investigated on the basis of the 1H and 13C NMR and UV-vis spectra. The rotational barrier (ΔG) around the exocyclic double bond of 8a was found to be 12.55 kcal mol−1 by the variable temperature 1H NMR measurement. The electrochemical properties of 8a,b were also studied by CV measurement. Furthermore, the transformation of 8a,b to 3-substituted 7,12-methanocycloundeca[4,5]furo[2,3-d]pyrimidine-2,4(1H,3H)-diones 16a,b was accomplished by oxidative cyclization using DDQ and subsequent ring-opening and ring-closure. The structural details and chemical properties of 16a,b were clarified. Reaction of 16a with deuteride afforded C13-adduct 19 as the single product, and thus, the methano-bridge controls the nucleophilic attack to prefer endo-selectivity. The photo-induced oxidation reaction of 16a and a vinylogous compound, 3-methylcyclohepta[4,5]furo[2,3-d]pyrimidine-2,4(3H)-dione 2a, toward some amines under aerobic conditions were carried out to give the corresponding imines (isolated by converting to the corresponding 2,4-dinitrophenylhydrazones) with the recycling number of 6.1-64.0 (for 16a) and 2.7-17.2 (for 2a), respectively.  相似文献   

17.
Three fluorescent quinazolines thiophen-2-yl-5,6-dihydrobenzo-[4,5]imidazo[1,2-c]quinazoline (1), pyridin-3-yl-5,6-dihydrobenzo-[4,5]imidazo-[1,2-c]quinazoline (2) and phenyl-5,5′,6,6′-dihydrobenzo-[4,4′,5,5′]imidazo-[1.1′,2-c,2′-c]quinazoline (3) have been synthesized. Structures of 1 and 3 have been authenticated crystallographically. Quinazolines 1-3 exhibit highly selective ‘on-off’ switching for Hg2+ ions. The fluorescence intensity displayed a linear relationship with respect to Hg2+ concentration (0.1-1.0 μM; R2 = 0.99) with detection limit of 2.0 × 10−7 M.  相似文献   

18.
The hydrolysis of 2-phenylethyl β-d-glucopyranoside (3) was found to be partially inhibited by feeding with 2-phenyl-N-glucosyl-acetamidiumbromide (8), a β-glucosidase inhibitor, resulting in a decrease in the diurnal emission of 2-phenylethanol (2) from Rosa damascena Mill. flowers. Detection of [1,1,2,2′,3′,4′,5′,6′-2H8]-2 and [1,2,2′,3′,4′,5′,6′-2H7]-2 from R. ‘Hoh-Jun’ flowers fed with [1,1,2,2′,3′,4′,5′,6′-2H8]-3 suggested that β-glucosidase, alcohol dehydrogenase, and reductase might be involved in scent emission. Comprehensive GC-SIM analyses revealed that [1,2,2,2′,3′,4′,5′,6′-2H8]-2 and [1,2,2,2′,3′,4′,5′,6′-2H8]-3 must be biosynthesized from [1,2,2,2′,3′,4′,5′6′-2H8] l-phenylalanine ([2H8]-1) with a retention of the deuterium atom at α-position of [2H8]-1.  相似文献   

19.
The preparation and inclusion properties of the new halo aryl hosts, 2,2′,7,7′,9,9′-hexahalo-9,9′-bisfluorenyl derivatives 5-7, are described. The host compounds 5-7 having four halogen atoms on the aromatic rings form stable inclusion crystals with many guest compounds, whereas the parent compound 4 does not. The X-ray structures of the host 4 and representative inclusion compounds of hosts 5-7 were determined, allowing rationalization of several of the experimental observations.  相似文献   

20.
Homogeneous catalytic carbonylation of some representative steroidal substrates (alkenyl iodides/enol triflates 1-5) has been carried out in the presence of (E)-1-(4′-aminophenyl)-3-ferrocenyl-prop-2-en-1-one (6) as the nucleophile. The products 1a-4a were obtained in moderate to good yield (43-75%) and were characterised with various spectroscopic methods (1H-, 13C NMR, IR, MS).The solid state structure of 17-(N-(4′-((2-ferrocenyl-ethenyl)-carbonyl)-phenyl)-carbamoyl)-5α-androst-16-ene (1a) has also been determined by X-ray crystallography.  相似文献   

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