2-Alkyl-4-amino-5-(tert-butyl-NNO-azoxy)-2H-1,2,3-triazole 1-oxides: synthesis and reduction

A new approach to the synthesis of 4-amino-5-(tert-butyl-NNO-azoxy)-2-R-2H-1,2,3-triazole 1-oxides 1 was developed. Compounds 1 were obtained by reactions of 3-amino-4-(tert-butyl-NNO-azoxy)furoxan with aliphatic amines RNH₂ (R = Me, Et, Prⁱ, Bu, and Bu^t). 4-Amino-5-(tert-butyl-NNO-azoxy)-2-tert-butyl-2H-1,2,3-triazole 1-oxide was transformed under the action of acids into 4-amino-5-(tert-butyl-NNO-azoxy)-1-hydroxy-1H-1,2,3-triazole. Methylation of the latter with diazomethane mainly involves the O atom of the triazole oxide ring. Reduction of compounds 1 gave 4-amino-5-(tert-butyl-NNO-azoxy)-2-R-2H-1,2,3-triazoles and 4-amino-5-(tert-butyldiazenyl)-2-R-2H-1,2,3-triazoles (R = Me, Prⁱ, and Bu^t). The structures of the compounds obtained were confirmed by ¹H, ¹³C, and ¹⁴N NMR spectroscopy.     

Transformations of 3(4)-amino-4(3)-(<Emphasis Type="Italic">tert</Emphasis>-butyl-<Emphasis Type="Italic">NNO</Emphasis>-azoxy)furoxans in the annulation reactions into 1,2,3,4-tetrazine 1,3-dioxides

Reactions of 3(4)-amino-4(3)-(tert-butyl-NNO-azoxy)furoxans with excess (NO₂)₂S₂O₇ or with a HNO₃—H₂SO₄—Ac₂O mixture unexpectedly produce [1,2,5]oxadiazolo[3,4-e]?[1,2,3,4]tetrazine 4,6-di-N-oxide (furazanotetrazine dioxide) and products of amino group oxidation (mainly to the corresponding azofuroxans) instead of the expected furoxanotetrazine dioxides. In some cases, individual (Z)-3,3´-((E)-diazene-1,2-diyl)-bis-((Z)-2-tert-butyl-1-oxidodiazenyl)-1,2,5-oxadiazole 2-oxide) was isolated. Formation of furazanotetrazine dioxides was observed in the reaction of 3-nitramino-4-(tert-butyl-NNO-azoxy)furoxan sodium salt with H₂SO₄ in Ac₂O. Quantum chemical calculation at the DFT/B3LYP/6-31G(d) level of theory was used to estimate several aspects of the reactivity of 3(4)-nitramino-4(3)-(tert-butyl-NNO-azoxy)furoxans in a comparison with 3(4)-nitramino-4(3)-phenylfuroxans and the possible causes of the observed transformations were revealed.     

Synthese von (5,10)-(7,8)-Bisepoxiden aus α- und β-4-Phenyl-1,2,4-triazolin-3,5-dion-Addukten von Vitamin D3 und Röntgenstrukturanalyse eines der Benzoylderivate

Oxidation of the α- and β-4-phenyl-1,2,4-triazolin-3,5-dione adducts of vitamin D₃ (2 and1) withMCPBA yields two diastereomeric mixtures of the (5,10)-(7,8)-dioxiranes3 a,3 b,3 c and4 a,4 b respectively. The corresponding benzoates5 a,5 b,6 a and6 b were prepared and the X-ray crystal structure of5 b was determined. This analysis proved5 b to be the (5R, 1 OS)-(7R, 8R)-dioxirane of the β-resp. (6S)-4-phenyl-1,2,4-triazolin-3,5-dione adduct1 of vitamin D₃.     

Silicon-carbon unsaturated compounds. 73. Photolysis of cis- and trans-1,2-dimethyl-1,2-diphenyl-1,2-disilacyclohexane in the presence of tert-butyl alcohol and acetone

Irradiation of cis-1,2-dimethyl-1,2-diphenyl-1,2-disilacyclohexane (1a) in the presence of tert-butyl alcohol in hexane with a low-pressure mercury lamp bearing a Vycor filter proceeded with high stereospecificity to give cis-2,3-benzo-1-tert-butoxy-1,4-dimethyl-4-phenyl-1,4-disilacyclooct-2-ene (2a), in 33% isolated yield, together with a 15% yield of 1-[(tert-butoxy)methylphenylsilyl]-4-(methylphenylsilyl)butane (3). The photolysis of trans-1,2-dimethyl-1,2-diphenyl-1,2-disilacyclohexane (1b) with tert-butyl alcohol under the same conditions gave stereospecifically trans-2,3-benzo-1-tert-butoxy-1,4-dimethyl-4-phenyl-1,4-disilacyclooct-2-ene (2b) in 41% isolated yield, along with a 12% yield of 3. Similar photolysis of 1a and 1b with tert-butyl alcohol-d₁ produced 2a and 2b, respectively, in addition to 1-[(tert-butoxy)(monodeuteriomethyl)(phenyl)silyl]-4-(methylphenylsilyl)butane. When 1a and 1b were photolyzed with acetone in a hexane solution, cis- and trans-2,3-benzo-1-isopropoxy-1,4-dimethyl-4-phenyl-1,4-disilacyclooct-2-ene (4a and 4b) were obtained in 25% and 23% isolated yield. In both photolyses, 1-(hydroxymethylphenylsilyl)-4-(methylphenylsilyl)butane (5) was also isolated in 4% and 5% yield, respectively. The photolysis of 1a with acetone-d₆ under the same conditions gave 4a-d₆ and 5-d₁ in 18% and 4% yields.     

Über substituierte 2-Amino-3,4,5,6-tetrahydro-1H-pyrimidinium-und 1,2,3,4,6,7,8,9-Octahydropyrimido-[1,2—a]pyrimidiniumchloride

Crotonaldehyde resp. cinnamaldehyde react with guanidiniumchloride to give 2-amino-6-guanidinio-4-methyl-3.4.5.6-tetrahydro-1H-pyrimidiniumdichloride (4 a) resp. 6-hydroxy-4-phenylpyrimidiniumchloride3 b and the 4.6-dihydroxy-2.8-dimethyl (resp. 2.8-diphenyl)octahydropyrimido[1.2?a]pyrimidiniumchlorides6 a and6 b, resp. Action of 2.4-(or 2.6-)xylenol on4 a resp.3 b yields 2-amino-6-[2(or 4)-hydroxy-3.5-dimethylphenyl]-4-methyl-(resp. 4-phenyl)-3.4.5.6-tetrahydro-1H-pyrimidiniumchlorides (8 a resp.8 b or9 a resp.9 b), which are transformed to the zwitterionic compounds10 a–11 b by aqu. NaOH.6 a reacts with 2.4-xylenol to give the triazaoxabenzanthraceniumchlorid12 a·HCl (prove for the structure given for6 a). The chemical properties and the NMR-, UV-, mass- and IR-spectra of the compounds are discussed.     

Generation of oxodiazonium ions 6. Unexpected formation of tetrazole 1-oxides

(E)-2-[2,2-Bis(tert-butyl-NNO-azoxy)-1-(methylsulfinyl)vinyl]-1-isopropoxydiazene 1-oxide reacts with boron trifluoride etherate (BF₃?Et₂O) producing 2-tert-butyl-N-nitro-2H-tetrazolo-5-carboxamide 4-oxide and 2-tert-butyl-2H-tetrazolo-5-carbonitrile 4-oxide but not the expected 1,2,3,4-tetrazine 1,3-dioxide derivative. This reaction direction can be explained by cationic domino cyclization, the key stage of which is coupling of the oxodiazonium ion with the geminal MeS(O) group. Structure of N-nitrocarboxamide was confirmed by X-ray diffraction analysis.     

Pyrrolide-imine benzyl complexes of zirconium and hafnium: synthesis, structures, and efficient ethylene polymerization catalysis

A series of pyrrolyl-imines HL^1-6 was prepared by the condensation of pyrrole-2-carboxyaldehyde with different amines. The reaction of 2 equiv of pyrrolyl-imine with tetrabenzyl complexes of hafnium and zirconium M(CH₂Ph)₄ (M=Hf or Zr) gave dibenzyl complexes (L^3-6)₂M(CH₂Ph)₂, which were characterized by NMR spectroscopy and crystal structure analysis. NMR spectra of the complexes with secondary alkyl substituents at the imine nitrogen (isopropyl: 3a, 4-tert-butylcyclohexyl: 4a and 4b) suggest that rapid racemization between Δ and Λ configurations occurs in solution on the NMR time scale. The complexes with pyrrolide-imine ligands with a tertiary alkyl group such as tert-butyl (5a and 5b) or 1-adamantyl (6a and 6b) at the imine nitrogen possess cis-configured benzyl groups. Hafnium complexes 5a and 6a react with B(C₆F₅)₃ in bromobenzene-d₅ to give the corresponding cationic benzyl complexes, which exhibit high activity for ethylene polymerization (5a: 2242 kg-polymer/ mol-Hf h bar, 6a: 2096 kg-polymer/ mol-Hf h bar). Zirconium complexes 5b and 6b display a remarkably high ethylene polymerization activity when activated with methylaluminoxane (5b: 17,952 kg-polymer/mol-Zr h bar, 6b: 22,944 kg-polymer/mol-Zr h bar).     

Biocatalytic desymmetrization of 3-substituted glutaronitriles by nitrilases. A convenient chemoenzymatic access to optically active (S)-Pregabalin and (R)-Baclofen

<正>1 General procedure for the preparation of 3-substituted glutaronitriles To a 100 mL flask containing aldehyde(30 mmol) and cyanoacetic acid(10.20 g, 120 mmol) was added 4-methylpiperidine(0.4 mL) and 23 mL N-methylmorpholine. The reaction mixture was warmed to mild reflux for 24 h and then cooled to room temperature and concentrated on a rotary evaporator. The resulting mixture was dissolved in 100     

Über die Bromierung von substituierten 3,4-Dihydro- und 6-Hydroxy- bzw. 6-Äthoxy-3,4,5,6-tetrahydro-2(1H)-pyrimidinonen

Bromination of 1-benzyl-4-methyl-3.4-dihydro-2(1H)-pyrimidinone (9 a) with 1 mole Br₂ in CHCl₃ yields 1-benzyl-5-bromo-6-hydroxy-4-methyltetrahydro-2(1H)-pyrimidinone,12 a, or the 6-ethoxypyrimidinone13 a, according to whether H₂O orEtOH is used in working up. With 2 moles Br₂,9 a analogously affords the 5.5-dibromopyrimidinnes14 a or15 a. Bromination of the 6-hydroxypyrimidinone10 a yields the same products,12 a and13 a, or14 a and15 a respectively, while the 4-phenyl-pyrimidinones9 b and11 b yield the corresponding 5-bromo-and 5.5-dibromopyrimidinones13 b and15 b. The structures of the compounds12 a-15 b are confirmed by their NMR data and chemical properties: the oxopyrimidinylmethylureas16 a and17 a are formed by the action of methylurea on12 a and13 a, or on14 a and15 a respectively; with hexamethylenetetramine,12 a reacts to give the 5.6-dihydroxypyrimidinone18 a, while13 b is transformed to the 4-phenylpyrimidinone19 b. 13 b was also synthesized from α-bromocinnamaldehyde. The mechanism of bromination is discussed.     

Stereochemie von α,ω-Diphenyl-alkan-α,ω-diolen

Reduction (both catalytically and with complex hydrides) of the diphenyl diketones1 (a, b, c andd withn=0, 2, 3 and 4) was investigated mainly with regard to the diastereomeric ratio of the diols2. For2 a and2 b exact results were obtained by NMR spectroscopy (without or with shift reagents) of the diol mixture (2 a) or after stereoselective cyclization to the cyclic ethers (3 b). AlsoGC andLLC were employed for the analysis of2 a (GC of the trimethylsilyl derivatives) and for the ethers3, resp. (GC for3 a and3 d;LLC for3 b and3 c). The reduction of1 a, 1 b (and in part1 c) proceeds with high stereoselectivity; themeso-diol preponderates in the case of2 a, therac.-diol for2 b and2 c; with increasingn the diastereomeric ratio approaches the statistical ratio of 1∶1. Preparations of the stereoisomeric diols (2 b, c andd via acetylenic precursors) and of the cyclic diphenyl ethers (by stereoselective cyclization and/or chromatographic separation;3 c and3 d for the first time) as well as the determination of their configurations are described. The latter was achieved by NMR and for the ethers3 also by hydrogenation of the corresponding heteroaromatics.     

Syntheses and spectroscopic characterization of double-armed benzo-15-crown-5 derivatives and their sodium and potassium complexes

A series of new benzo-15-crown-5 derivatives (1–6) containing formyl and imine groups were prepared. New formyl crown ethers (1 and 2) were prepared by reaction of 4′,5′-bis(bromomethyl)benzo-15-crown-5 with 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 2-hydroxy-5-methoxybenzaldehyde in the presence of NaOH. New Schiff bases (3–6) were synthesized by the condensation of corresponding aldehydes with 1,3-diaminopropane and 1,4-diaminobutane. Sodium and potassium complexes (1a–6a and 1b–6b) of the crown compounds forming crystalline complexes of 1:1 (Na⁺:ligand) and 1:2 (K⁺:ligand) stoichiometries were also synthesized. The structures of the aldehydes 1 and 2, imines 3–6 and complexes (1a–3a and 1b–3b) were confirmed on the basis of elemental analyses, IR, ¹H- and ¹³C-NMR, and mass spectroscopy.     

Synthesis and characterization of a series of chiral NHC–Pd complexes derived from l-phenylalanine

The synthesis of a series of chiral Pd(L)PyBr₂ (3a–3e) and Pd(L)PyCl₂ (4d and 4e) complexes from l-phenylalanine is presented (L = (S)-3-allyl-4-benzyl-1-(2,6-diisopropylphenyl)-imidazolin-2-ylidene (a), (S)-4-benzyl-1-(2,6-diisopropylphenyl)-3-(naphthalen-2-ylmethyl)imidazolin-2-ylidene (b), (S)-4-benzyl-3-(biphenyl-4-ylmethyl)-1-(2,6-diisopropylphenyl)imidazolin-2-ylidene (c), (S)-4-benzyl-1-(2,6-diisopropylphenyl)-3-(naphthalen-1-ylmethyl)imidazolin-2-ylidene (d) or (S)-4-benzyl-1-(2,6-diisopropylphenyl)-3-(2,4,6-trimethylbenzyl)imidazolin-2-ylidene (e). The complexes were characterized by physicochemical and spectroscopic methods, and the X-ray crystal structures of 3a–3c and 4d are reported. In each case, there is a slightly distorted square-planar geometry around palladium, which is surrounded by imidazolylidene, two trans halide ligands and a pyridine ligand. There are π–π stacking interactions in the crystal structures of these complexes. Complex 3a showed good catalytic activity in the Cu-free Sonogashira coupling reaction under aerobic conditions.     

Tribromogermyl monochelates — derivatives of N,N-disubstituted 2-hydroxycarboxylic amides

Reactions of GeBr₄ with N,N-dimethyl-2-trimethylsiloxypropionamide (2a), (S)-2-trime-thylsiloxypropionpyrrolidide ((S)-2b), and N,N-dimethyl-O-(trimethylsilyl)mandelamide (2c) afforded pentacoordinated neutral (O,O)-monochelates, viz., N,N-dimethyl-2-tribromoger-myloxypropionamide (3a), (S)-2-tribromogermyloxypropionpyrrolidide ((S)-3b), and N,N-dimethyl-O-(tribromogermyl)mandelamide (3c), respectively. X-ray diffraction study was performed for tribromides 3a, (S)-3b, and 3c, as well as for the N,N-dimethylmandelamide (1c) described earlier. According to the X-ray diffraction data, the Ge atom in tribromides 3a, (S)-3b, and 3c is pentacoordinated and has trigonal bipyramidal configuration with two halogen atoms and oxygen atom of the ether group in the equatorial positions and the halogen atom and the amide oxygen atom in the axial fragment, the bonds in which are somewhat longer as compared to the analogous bonds in tetracoordinated Ge compounds.     

Über cyclische Guanidin—Mesityloxid- und Guanidin—Phoron-Kondensate

The basic product synthesized byTraube andSchwarz from mesityl oxide and guanidine has not been 4.4.6-trimethyl-4.5-dihydro-2-pyrimidinamine (1), but a mixture containing the 4.4.6-trimethyl-3.4-dihydro-2(1H)-pyrimidinimine (resp. an isomeric pyrimidinamine)2 a (resp.2 b, 2 c) and the dimeric 4.4′-methylenedi[2(1H)-pyrimidinimine] (resp. an isomeric methylenedipyrimidinamine)3 a (resp.3 b, 2 c) and the dimerisation reaction were studied in a series of experiments. The product of the reaction of guanidine and phorone is not the guanidinopropylpyrimidine8 ⁴, but the 4.4′-spirobi[2(1H)-pyrimidinimine] (resp. a spirobipyrimidinamine)11 a (resp.11 b, 11 c). No determination was possible on the basis of NMR whether the condensation products of guanidine—in solutions ofDMSO-d₆—are pyrimidinimines (2 a, 3 a, 11 a) or pyrimidinamines (2 b resp.2 c, 3 b resp.3 c, 11 b resp.11 c) or mixtures of the isomeric compounds. The NMR-and mass spectra of2 a (resp.2 b, 2 c),3 a (resp.3 b, 3 c),11 a (resp.11 b, 11 c) and their derivates are discussed.     

Convenient synthesis of 3-fluoro-4,5-diphenylfuran-2(5H)-one from benzoin ethers : Novel and efficient Z-E isomerisation and cyclisation of 2-fluoroalkenoate precursors, substitution of vinylic fluorine

Mixtures of ethyl (E)- and (Z)-4-alkoxy-2-fluoro-3,4-diphenylbut-2-enoates (6-8) prepared from benzoin ethers and ethyl 2-(diethoxyphosphoryl)-2-fluoroacetate were transformed in high yields to the target 3-fluoro-4,5-diphenylfuran-2(5H)-one (14) using bromine in tetrachloromethane at room temperature. The non-cyclisable Z-isomers 6b-8b were gradually isomerised to the cyclisable E-isomers 6a-8a during the process. The reaction of the (E)-butenoates 6a-8a with boron trifluoride led to furanone 14, while in Z-isomers 6b-8b both alkoxy group and vinylic fluorine were substituted with bromine during the reaction. Mechanisms for both complex reactions have been proposed. Furanone 14 was transformed to 2-[tert-butyl(dimethyl)silyloxy]-3-fluoro-4,5-diphenylfuran (18) as a novel building block.     

Carbon-nitrogen bond formation in the reaction of the reaction of diphenyl diazomethane Ph2 CN2 with diiron-carbene complexes (Fe2(CO)7x03BD;-C(R)C(NEt2)x03BD;-C(R)C(NEtx03BC;-C(R)C(NEt2)N(NCPh2)x03BC;-C(R)C(NEtx03BC;-C(R)C(NEt2)NN(CPh2)x03BC;-C(R)C(NEt)]

The diiron ynamine complex [Fe₂(CO)₇{μ-CR)C(NEt₂)}] (1:R=Me,2:R = C₃H₅.3:R=SiMe₃.4:R = Ph) reacts at room temperature with diphenyldiazomethane Ph₂CN₂, in hexane to yield complexes [Fe₂(CO)₆{C(R)C(NEt₂)N (NCPh₂)] (5a:R=Me,6a:R=C₃H₅.7a R=SiMe₃.8a:R=Ph) resulting from the insertion of the terminal nitrogen atom into the Fe=C carbene bond. Insertion the second nitrogen atom and formation of compounds [Fe₂(CO)₆zμ-C(R)C(NEt₂)NN(CPh₂)}] (5b:R=Me,6b:R=C₃H₅,7b:R=SiMe₃,8b:R=Ph) is observed when compounds5a-5a are treated in refluxing hexane. Transformation of compoundsa tob is also obtained at room temperature within a few days. All compounds were identified by their¹H NMR spectra. Compounds6a, 7a, 8a, and8b were characterized by single crystal X-ray diffraction analyses. Crystal data: for6a: space group = P2₁/n,a=12.853(1) A,b=24.800(7) A,c=8.947(6) A,β=99.29(3)°,Z=4, 2227 rellectionsR=0,038; for7a: space group=Pl,a=ll.483(4) A,b=14.975(4) A,c = 17.890(8) A,α = 82.80(3)°,β=94.29(7)°,γ=85.42(2),Z = 4, 5888 reflectionR = 0.035: for8a: space group = Pcab.a = 31.023(8) A.b=20.137(1) A.c=9.686(2) A.Z=8. 1651 reflections,R=0.071; for8b: space group=P2₁/n,a=21.459(4),b=10,100(3) A,c=28,439(8) A,ß=103.86(4)°,Z=8. 2431 reflections.R=0.057.     

Synthese,Kristallstruktur und Konformation vontrans-[2.2](1,2)Ferrocenophan und seinen 1-Hydroxyderivaten

Starting from1-(dimethylaminomethyl)-2-iodo-ferrocene (3) [2.2](1,2)ferrocenophane (2) was prepared in an 8-step synthesis with 17% overall yield. Both from the oxoderivative12 and the ferrocenophane2 puretrans-isomers (12b and2b, resp.) were obtained; the former (12b) was reduced to a separable mixture ofexo andendo 1-hydroxy-ferrocenophanes13a andb, resp. (～ 3:7), the configurations of which were assigned by the LIS-method. X-ray crystal structure analysis of2b revealed a centrosymmetrical chair conformation. From¹H- and¹³C-NMR spectra both for2b and for the hydroxyderivatives13 a rigidexo-exo chair conformation was deduced.     

Chinolizine und Indolizine,XIII. Acyl-2-hydroxy-4-chinolizinone

The reaction of 2-picolylketones (1 a, b) with reactive trichlorophenyl malonates (2 a–f) leads to 1-acyl-2-hydroxy-4-quinoliziones (3 a–i) which can be easily deacylated by boiling hydrochloric acid yielding 4-quinolizinones4 a–f. The 3-acetyl-2-hydroxy-4-quinolizinones6 and8 are obtained byKlosa-Ziegler acylation of4 a and7, respectively. The reaction of the acetyl compound3 a with acetic anhydride yields the 2-pyrone derivative9, whereas the propionyl derivative3 g yields the 4-pyrone10 under the same conditions. Nitration of3 e does not give the 1-nitro derivative12 but rather the 1,3-dinitro compound11.     

Strukturelle Abwandlungen an Nukleotiden,Nukleosiden und Nukleosidbasen mit β-Acylvinylphosphoniumsalzen

β-Acetylvinyl-triphenylphosphonium bromide1 reacts with CMP to form the 3,N⁴-etheno-derivative {[6-(5′-phosphoribofuranosyl)-2-methyl-5-oxo-imidazo [1.2-c]pyrimidin-3-yl]-methyl}triphenyl-phosphonium bromide (2). Guanine affords mainly the lin. condensation product [(6-methyl-9-oxo-imidazo[1.2-a]-purin-7-yl)-methyl]triphenylphosphonium bromide (3) and the angular tricyclic product [(6-methyl-9-oxo-imidazo[2.1-b]purin-5-yl)-methyl]-triphenylphosphonium bromide (4). For comparison we synthesized the angular condensed heterocycle5, (6.8-dimethyl-9-oxo-imidazo[2.1-b]purin-5-yl)-methyl]triphenylphosphonium bromide, by reaction of 1-methylguanine with1, and the corresponding linear derivative6 [(4.6-dimethyl-9-oxo-imidazo[1.2-a]purin-7-yl)-methyl]-triphenylphosphoniumbromide from 3-methylguanine and1. AHofmann-type degradation of3 with the anion of diethyl malonate led to7, diethyl (6-methyl-9-oxo-imidazo[1.2-a]purin-7-yl)-methylmalonate, a compound whose structure resembles some Y-bases in t-RNA.Wittig reaction of the silylated nucleoside derivative8 a {[2-methyl-5-oxo-6-(2′.3′.5′-tris-trimethylsilyl)-ribofuranosyl-imidazo[1.2-c]pyrimidin-3-yl]methyl}-triphenylphosphonium bromide, with C₆H₅CHO resulted in the 2-methyl-3(ω-styryl)-6[2′.3′.5′-tris-(trimethylsilyl)]ribofuranosyl-imidazo[1.2-c] pyrimidin-5-one (9).     

Cytotoxicity evaluation of coumarin derivatives containing 4-bromophenyl or anthracene moieties

The cytotoxic properties of four synthesized coumarin derivatives containing 4-bromophenyl or anthracene moieties against the human hepatocellular carcinoma cell lines (HepG-2) were investigated in vitro by use of the sulforhodamine B (SRB) assay. The four coumarin derivatives are 3-(4-bromophenyl)-benzo[5,6]coumarin (1a), 3-(4-bromophenyl)-7-(N,N-diethylamino)coumarin (1b), 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin (2a), and 3-(4-(anthracen-10-yl)phenyl)-7-(N,N-diethylamino)coumarin (2b). The preliminary results indicate that 1a, 2a, and 2b have significant cytotoxicity against HepG-2 whereas 1b has a growth-promotion effect.