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1.
Yoshimitsu Yamazaki Hideo Suzuki Akira Kamibayashi Naoharu Watanabe Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(9):1945-1950
Five new derivatives of adenosine, N6-[(1-methylethyl)thiomethyl]-(1), N6-methyithiomethyl-(2), N6-phenylthiomethyl-(3), N6-[(3-amino-3-carboxypropyl)thiomethyl]-(4), and N6-[(2-amino-2-carboxyethyl)thiomethyl]adenosine (5), were synthesized and their cytokinin activity was tested in the Amaranthus betacyanin assay and the soybean callus growth.1, 2, and 3 were active in the former assay and all five compounds were active in the latter assay. The activities of the compounds were, however, weaker than those of the reference derivatives, in which Sulfides were replaced by methylenes, N6-isopentyl-, N6-n-propyl-, N6-benzyl-, and N6-(5-amino-5-carboxypentyl)adenosine. This fact indicates that the sulfide structure introduced into the N6-side chains had the effect of reducing cytokinin activity. 相似文献
2.
Gang-Liang Huang Xin-Ya Mei 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):247-249
The penta-N-acetyl-chitopentaose 2 has been prepared by using recombinant E. coli strains harboring the nodC gene (encoding chitooligosaccharide synthase) from Azorhizobium caulinodans. Then, the deacetylase NodB removed the N-acetyl moiety from the nonreducing terminus of 2 to give tetra-N-acetyl-chitopentaose 3. N-Acylation of 3 with stearyl chloride was performed in DMF containing water and provided the corresponding lipo-chitopentaose nodulation factor 4. A binding chitinase assay indicated that 4 was much more stable than 3. 相似文献
3.
It was suggested that the abnormally high N 2 O values found in 130,000–160,000 year-old Vostok ice core samples, characterized by high δ 15 N and low δ 18 O values, resulted from in situ microbial N 2 O production. To substantiate these observations we obtained new geochemical data from the last glacial period and showed the existence of additional small N 2 O anomalies. To test the hypothesis that microbial metabolism could contribute to these anomalies, we developed protocols for examining the ability of Nitrosomonas cryotolerans cells to produce N 2 O at subfreezing temperatures. Our results show that these model, frozen cultures produce N 2 O at temperatures as low as ?32°C. 相似文献
4.
Ashty Saleh Frans Compernolle Gerard Janssen 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):689-692
Abstract We report an improved synthesis of N 6-(6-aminohexyl)FAD (1) using an efficient one-pot conversion of inosine to the N-trifluoroacetyl protected N 6-(6-aminohexyl)adenosine 3. The 5′-O-phosphorylated AMP derivative 4, activated as the imidazolide, was coupled with commercial sodium riboflavin phosphate by using 18-crown-6 in DMF. 相似文献
5.
Several bis-amino acids were prepared using a bis-Suzuki coupling (compounds 4–8, 10), a sequential Michael addition and bis-Suzuki coupling (compounds 12, 13) and a Michael addition followed by a substitution reaction (compounds 18, 19). Thus, the pure stereoisomer of the methyl esters of N-(tert-butoxycarbonyl)-β-bromodehydroaminobutyric acid and dehydrophenylalanine and of N-benzyloxycarbonyl-β-bromodehydroaminobutyric acid were reacted with 1,4-phenylene-bis-boronic acid or 9,9-dioctyl-9H-fluorene-2,7-bis-boronic acid using modified Suzuki coupling conditions. The corresponding bis-dehydroamino acid derivatives
were obtained in good to high yields maintaining the stereochemistry of the starting materials. This reaction was also applied
successfully to a brominated dehydrodipeptide and 1,4-phenylene-bis-boronic acid showing that it could be used to create cross-links
in peptide chains. An N,N-diacyldehydroalanine derivative was used in a sequential Michael addition and bis-Suzuki coupling giving a p-terphenyl bis-amino acid and a fluorenyl bis-amino acid in good yields. Two bis-α,β-diamino acids were obtained by a Michael
addition of 1,2,4-triazole to the methyl esters of N-(4-toluenesulfonyl), N-(tert-butoxycarbonyl) dehydroamino acids followed by treatment with ethylenediamine. 相似文献
6.
《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):227-237
The regioselective synthesis of 4‐nitroindazole N 1‐ and N 2‐(β‐d‐ribonucleosides) (8, 9, 1b and 2b) is described. The N 1‐regioisomers are formed under thermodynamic control of the glycosylation reaction [fusion reaction or Silyl Hilbert‐Johnson glycosylation for 48 h (66%)], while the kinetic control (Silyl Hilbert‐Johnson glycosylation for 5 h) afforded only the N 2‐isomer (64%). The structures of the nucleosides 1b and 2b were assigned by single crystal X‐ray analyses. The 4‐amino‐N 1‐(β‐d‐ribofuranosyl)‐1H‐indazole (3b) was obtained from the nitro nucleoside 1b by catalytic hydrogenation. Compound 3b shows fluorescence while the 4‐nitroindazole nucleosides 1b and 2b do not possess this property. 相似文献
7.
Abstract From the carbolithiation of 6-bis-N,N-dimethylamino fulvene (3a) and different ortho-lithiated heterocycles (furan, thiophene and N-methylpyrrole), the corresponding lithium cyclopentadienide intermediate (4a–c) was formed. These three lithiated intermediates underwent a transmetallation reaction with TiCl4 resulting in bis-N,N-dimethylamino-functionalised titanocenes 5a–c. When these titanocenes were tested against LLC-PK cells, the IC50-values obtained were of 240, and 270 μM for titanocenes 5b and 5c, respectively. The most cytotoxic titanocene in this paper, 5a with an IC50-value of 36 μM was found to be approximately six times less cytotoxic than its mono-N,N-dimethylamino substituted analogue Titanocene C (IC50 = 5.5 μM) and almost ten times less cytotoxic than cisplatin, which showed an IC50-value of 3.3 μM, when tested on the LLC-PK cell line.
Graphical abstract Bis-(bis- (N,N-dimethylamino)-2-(N′-methylpyrrolyl)methylcyclopentadienyl) titanium (IV) dichloride, {η5-C5H4-CH[N(CH3)2]2[C5H3NCH3]}2TiCl2 was synthesised starting from 6-bis-(N,N-dimethylamino) fulvene and 2-N-methylpyrrolyl lithium. Herein, we present the synthesis and DFT structure of the titanocene and two further derivatives
followed by MTT-based cytotoxicity tests on pig kidney epithelial (LLC-PK) cells.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
8.
Ulla Henriksen 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1093-1100
Abstract N-(1-alkenyl) derivatives of 2,4-pyrimidinediones (6–9) were prepared in a one pot synthesis from aldehydes and the nucleobases using trimethylsilyl trifluoromethanesulfonate (TfOTMS) as coupling reagent. Presilylation of the above nucleobases, and N 6-benzoyladenine, with excess N,O-bis(trimethylsilyl)acetamide (BSA) followed by addition of one mol eq. TfOTMS yielded the N-(1-trimethylsilyloxyalkyl) derivatives 1–5. 相似文献
9.
Four isobutyl amides were isolated from the fruits of white pepper (Piper nigrum L.) and identified to be N-isobutyl-13-(3,4-methylenedioxyphenyl)-2E,4E,12E-tridecatrienamide (3, guineensine), N-isobutyl-2E,4E,8Z-eicosatrienamide (5), N-isobutyl-2E,4E-octadecadienamide (6) and N-isobutyl-2E,4E-decadienamide (7, pellitorine). 相似文献
10.
J. M. J. Tronchet M. Zsély E. Grand N. Laroze M. Iznaden M. Sollini 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):649-650
Abstract A variety of modified nucleosides or dinucleosides bearing one of the following functions have been prepared: N-hydroxyureas, N-hydroxyamines, N-hydroxycarbamates, α-(N-hydroxyamino)phosphonates. Upon oxidation, these compounds afford the corresponding aminoxyl free radicals which have been studied by EPR spectroscopy. Some of these compounds exhibited antiviral properties. 相似文献
11.
Summary.
N-[(Z)-N-Benzoyl- or N-boc-(2-fluorophenyl)dehydroalanyl]-(R)- or (S)-phenyl-alanines 1,2,5 and 6 were hydrogenated in the presence of chiral and achiral rhodium complexes. The optical induction is compared to the results
obtained using the corresponding esters as substrates.
Received November 11, 2001 Accepted January 15, 2002 相似文献
12.
Interaction of (2′ -5′) and (3′ -5′) Linked 2-Aminoadenylyl-3-aminoadenosines with Polyuridylic Acid
Masako Muraoka Seizo Takahashi Seiichi Uesugi 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1503-1518
Abstract 2′-5′ and 3′-5′ linked 2-aminoadenylyl-2-aminoadenosines [(2′-5′)n2Apn2A (1) and (3′-5′)n2Apn2A (2)] were synthesized by condensation of 5′-O-monomethoxytrityl-N 2 N 6-dibenzoyl-2-aminoadenosine and N 2,N 6,2′,3′-O-tetrabenzoyl-2-aminoadenosine 5′-phosphate using dicyclohexylcarbodiimide (DCC). The conformational properties of these dimers 1 and 2 were examined by UV, NMR and CD spectroscopy. The results reveal that the 2′-5′-isomer 1 takes a stacked conformation, which contains a larger base-base overlap and is more stable against thermal perturbation with respect to the 3′-5′-isomer 2. Interactions of 1 and 2 with polyuridylic acid (Poly (U)) were also examined by Tm, mixing curves, UV and CD spectra. Both the dinucleoside isomers 1 and 2 formed a complex of 1 : 2 stoichiometry with poly(U), which was much more stable than that of the corresponding ApA isomer 相似文献
13.
Yohei Koga Yosuke Taniguchi Shigeki Sasaki 《Nucleosides, nucleotides & nucleic acids》2013,32(3):124-136
6-O-7-N-Bis(diphenylcarbamoyl)-2-N-phenoxyacetyl-5′-O-dimethoxytrityl-2′-O-{[(triisopropyl- silyl)oxy]methyl}-8-oxoguanosine-3′-yl-β-cyanoethyl-N,N-diisopropylphosphoramidite (5) was synt- hesized as a new phosphoramidite precursor unit for the synthesis of RNA. Compound 5 was successfully incorporated into the middle of the RNA sequences, and the synthesized RNAs were identified by MALDI-TOF mass measurements. Their properties were evaluated for formation of the RNA duplex and RNA/DNA heteroduplex. ORNs 1 and 4 containing 8-oxo-G can form base pairs with rC or dC in an anti conformation, while it can also interact with rA or dA in a syn conformation in the RNA duplex or RNA/DNA heteroduplex. The described synthetic method is therefore a useful procedure for the synthesis of ORN containing 8-oxo-G and contributes to the study of 8-oxo-G in RNA. 相似文献
14.
Annegret Hille Ingo Ott Ana Kitanovic Igor Kitanovic Hamed Alborzinia Elke Lederer Stefan Wölfl Nils Metzler-Nolte Sven Schäfer William S. Sheldrick Caroline Bischof Ulrich Schatzschneider Ronald Gust 《Journal of biological inorganic chemistry》2009,14(5):711-725
We developed N,N′-bis(salicylidene)-1,2-phenylenediamine (salophene, 1) as a chelating agent for metal ions such as Mn(II/III), Fe(II/III), Co(II), Ni(II), Cu(II), and Zn(II). The resulting complexes,
from which owing to the carrier ligand a selective mode of action is assumed, were tested for antiproliferative effects on
the MCF-7 breast cancer cell line. The cytotoxicity in this assay depended on the nature of the transition metal used. Iron
complexes in oxidation states +II and +III (3, 4) strongly reduced cell proliferation in a concentration-dependent manner, whereas, e.g., the manganese analogues 5 and 6 were only marginally active. Therefore, the [N,N′-bis(salicylidene)-1,2-phenylenediamine]iron(II/III) complexes 3 and 4 were selected for studies on the mode of action. Both complexes possessed high activity against various tumor cells, for
instance, MDA-MB-231 mammary carcinoma cells as well as HT-29 colon carcinoma cells. They were able to generate reactive oxygen
species, showed DNA binding, and induced apoptosis. Exchange of 1 by N,N′-bis(salicylidene)-1,2-cyclohexanediamine (saldach, 2) yielding complexes 7 and 8 reduced the in vitro effects drastically. An unequivocal mode of action cannot be deduced from these results, but it seems
to be very likely that cell death is caused by interference with more than one intracellular target.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
Sh. H. Abdel-Hafez 《Russian Journal of Bioorganic Chemistry》2010,36(3):370-376
Synthesis of 3-[4-(N-substituted sulfamoyl)phenyl]-3,4-dihydro-4-oxo-7,9-dimethylpyri-do[3′,2′:4,5]selenolo[3,2-d]pyrimidines,7-[4-(N-substituted sulfamoyl)phenyl]-7,8-dihydro-8-oxo-3,4-diphenylpyrimido[4′,5′:4,5]selenolo [2,3-c]pyridazines and 1-[4-(N-substituted sulfamoyl)phenyl]-1,11-dihydro 11-oxo-4-methylpyrimido[4′,5′:4,5]selenolo[2,3-b]quinolines is reported. 4-Amino-N-pyrimidine-2-ylbenzene sulfonamide (a), 4-amino-N-(2,6-dimethylpyrimidin-4-yl)benzene sulfonamide (b), N-[(4-aminophenyl)sulfonyl] acetamide (c) with N-ethoxymethyleneamino of selenolo pyridine, selenolo pyridazine and selenolo quinoline derivatives respectively were obtained
starting from 1-amino-N
4-substituted sulfanilamides. Spectroscopic data (IR, 1H NMR, 13C NMR and Mass spectral) confirmed the structure of the newly synthesized compounds. Substituted
pyrimidines, pyridazines and quinolines were screened for antibacterial activity against gram-positive and gram-negative bacteria. Selenolo derivative of N-[(4-aminophenyl)sulfonyl] acetamide (substitutent of sulfacetamide c) showed strong bactericidal effect against all the tested
organisms. Selenolo[3,2-d]pyrimidin (substitutent a) showed a good bactericidal effect against Serratia marcescens, Staphylococcus aureus and Escherichia coli. Compounds selenolo[2,3-c]pyridazine (substitutent b), selenolo[2,3-b]quinoline(substitutents c)) exhibited a moderate bactericidal effect against Serratia marcescens. None of the synthesized seleno pyridazines has a considerable antimicrobial activity against the tested organisms. The minimum
inhibitory concentration (MIC) of the most active compound-3-[4-(N-acetyl sulfamoyl)phenyl]-3,4-dihydro-4-oxo-7,9-dimethylpyrido[3′,2′:4,5]selenolo [3,2-d]pyrimidine was 10 mg ml−1. 相似文献
16.
J. Hlaváček J. Pícha V. Vaněk J. Jiráček J. Slaninová V. Fučík M. Buděšínský D. Gilner R. C. Holz 《Amino acids》2010,38(4):1155-1164
A series of N
α-acyl (alkyl)- and N
α-alkoxycarbonyl-derivatives of l- and d-ornithine were prepared, characterized, and analyzed for their potency toward the bacterial enzyme N
α-acetyl-l-ornithine deacetylase (ArgE). ArgE catalyzes the conversion of N
α-acetyl-l-ornithine to l-ornithine in the fifth step of the biosynthetic pathway for arginine, a necessary step for bacterial growth. Most of the
compounds tested provided IC50 values in the μM range toward ArgE, indicating that they are moderately strong inhibitors. N
α-chloroacetyl-l-ornithine (1g) was the best inhibitor tested toward ArgE providing an IC50 value of 85 μM while N
α-trifluoroacetyl-l-ornithine (1f), N
α-ethoxycarbonyl-l-ornithine (2b), and N
α-acetyl-d-ornithine (1a) weakly inhibited ArgE activity providing IC50 values between 200 and 410 μM. Weak inhibitory potency toward Bacillus subtilis-168 for N
α-acetyl-d-ornithine (1a) and N
α-fluoro- (1f), N
α-chloro- (1g), N
α-dichloro- (1h), and N
α-trichloroacetyl-ornithine (1i) was also observed. These data correlate well with the IC50 values determined for ArgE, suggesting that these compounds might be capable of getting across the cell membrane and that
ArgE is likely the bacterial enzymatic target. 相似文献
17.
Teruaki Mukaiyama Masashi Nagai Takafumi Matsutani Naoyuki Shimomura 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):17-30
Abstract Several β-d-ribonucleosides were synthesized in high yields under mild conditions by N-glycosylations of methyl 2,3,5-tri-O-benzoyl-β-d-ribofuranosyl carbonate (1) with trimethylsilylated nucleoside bases in acetonitrile using a catalytic amount of metal iodide such as SnI2, SbI3 or TeI4. A deprotection of N6 -benzoyl group of coupling product took place to a considerable extent when N6 -benzoyl-N6 , N9 -bis(trimethylsilyl)adenine was employed as a nucleoside base using SnI2 or SnCI2 as a catalyst while it was minimized when SbI3 or TeI4 was used. Further, the N-glycosylation of 1 with 7-trimethylsilyltheophylline in the presence of a catalytic amount of metal iodide was more effectively achieved in nitrile solvents other than acetonitrile. 相似文献
18.
E. Lescrinier C. Pannecouque J. Rozenski A Van Aerschot L Kerremans P. Herdewijn 《Nucleosides, nucleotides & nucleic acids》2013,32(11-12):1863-1869
Abstract N 6-ablated adenosine can be synthesized by reduction of the corresponding carboxylic acid amides using Lm. Starting from 2′,3′-O-isopropylidene adenosine, N 6-ethyladenosine, N 6-propyladenosine, N 6-isobutyladenosine, N 6-benzyladenosine and N 6-furfuryladenosine were obtained in a three step procedure (acylation, reduction, deprotection). 相似文献
19.
Summary. The two fMLF-OMe analogues For-Met-β3hAc6c-Phe-OMe (6) and For-Met-β2hAc6c-Phe-OMe (12) and their corresponding N-Boc derivatives 5 and 11 have been synthesized and their biological activity towards human neutrophils evaluated. The N-formyl peptides 6 and 12 exhibit good activity as chemoattractans and 12 is highly active in superoxide anion production. The preferred solution conformation of the two N-formyl derivatives has been discussed. 相似文献
20.
G. Ceulemans K. Khan A. Van Schepdael P. Herdewijn 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):813-816
Abstract Reaction of N-Boc-L-homoserine benzylester with N3 -benzoylthymine under Mitsunobu conditions afforded N-Boc-L-α-amino-γ-N3 -benzoylthymine butyric acid benzylester. After removal of the N-benzoyl and O-benzyl protecting group, this compound was used in solution phase peptide synthesis. 相似文献