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1.
Yasumasa Kuwahara 《Bioscience, biotechnology, and biochemistry》2013,77(11):1855-1866
ABSTRACT(2-Nitroethyl)benzene, methyl 4-methoxybenzoate and 4-methoxybenzaldehyde have been known as major scent components in flowers of the Japanese loquat Eriobotrya japonica [Rosales: rosaceae], together with 13 related benzenoids, including Z- and E-2-phenylacetaldoxime and benzyl alcohol. The scents air-trapped from a flowering panicle during 24 h incubation with d8-L-phenylalanine were composed of 15 deuterium labeled compounds {d6-styrene, d5-benzaldehyde, d7-2-phenylacetaldehyde, methyl d5-benzoate, d7 ?2-phenylethanol, d7-2-phenylacetonitrile, d4-1,4-dimethoxybenzene, d7-Z-2-phenylacetaldoxime, d4-4-methoxybenzaldehyde, d7-E-2-phenylacetaldoxime, d4-4-methoxybenzyl alcohol, d7-(2-nitroethyl)benzene, methyl d4-4-methoxybenzoate, methyl d6-cinnamate and ethyl d4-4-methoxybenzoate}. On the other hand, hexane extracts of the flower petal incubate with a mixture of d5-Z- and d5-E-2-phenylacetaldoxime after 24 h indicated generation of six d5-labeld components {d5-benzaldehyde, d5-benzyl alcohol, d5-2-phenylacetaldehyde, methyl d5-benzoate, d5-2-phenylethanol, and d5-(2-nitroethyl)benzene}. By comparing those results, (2-nitroethyl)benzene was concluded as a product directly generated from a mixture of Z- and E-2-phenylacetaldoxime together with six minor benzenoids, while two major compounds (4-methoxybenzaldehyde and methyl 4-methoxybenzoate) together with three minors from L-phenylalanine, presumably via L-tyrosine. The other two minor components were derived from L-phenylalanine. 相似文献
2.
Ana Delia Gisbert José Martínez-Calvo Gerardo Llácer María Luisa Badenes Carlos Romero 《Molecular breeding : new strategies in plant improvement》2009,23(3):523-538
Loquat [Eriobotrya japonica (Thunb.) Lindl.] is a Rosaceae fruit species of growing interest as an alternative to the main fruit crops. However, only
a few genetic studies have been carried out on this species. This paper reports the construction of the first genetic maps
of two loquat cultivars based on AFLP and microsatellite markers from Malus, Eriobotrya, Pyrus and Prunus genera. An F1 population consisting of 81 individuals, derived from the cross between ‘Algerie’ and ‘Zaozhong-6’ cultivars, was used to
construct both maps. A total of 111 scorable simple sequence repeat (SSR) loci resulted from the testing of 440 SSR primer
pairs in the analyzed progeny and the SSR transferability to Eriobotrya was found to be 74% from apple, 58% from pear and 49% from Prunus spp. In addition, 183 AFLP polymorphic bands were produced using 42 primer combinations. The ‘Algerie’ map was organized
in 17 linkage groups covering a distance of 900 cM and comprising 177 loci (83 SSRs and 94 AFLPs) with an average marker distance
of 5.1 cM. Self-incompatibility trait was mapped at the distal part of the LG17 linkage group, as previously reported in Malus and Pyrus. The ‘Zaozhong-6’ map covered 870 cM comprising 146 loci (64 SSRs and 82 AFLPs) with an average marker distance of 5.9 cM.
The 44 SSRs and the 48 AFLPs share in common by both maps were essentially collinear and, moreover, the order of the 75% of
apple and pear SSRs mapped in Eriobotrya was shown to be consistent across the Maloideae subfamily. As a whole, these maps represent a useful tool to facilitate loquat
breeding and an interesting framework for map comparison in the Rosaceae. 相似文献
3.
Synthesis of (R)-2-trimethylsilyl-2-hydroxyl-propionitrile via asymmetric transcyanation of acetyltrimethylsilane with acetone cyanohydrin in an aqueous/organic biphasic system catalyzed by (R)-hydroxynitrile lyase from Prunus japonica seed meal was successfully carried out for the first time. The optimal volume ratio of aqueous to organic phase, buffer pH value and reaction temperature were 15% (v/v), 5.0 and 30°C, respectively, under which both substrate conversion and product enantiomeric excess (ee) were 99%. Silicon atom in the substrate showed great effect on the reaction. Acetyltrimethylsilane was a much better substrate for (R)-hydroxynitrile lyase from Prunus japonica than its carbon analogue. 相似文献
4.
Synthesis of (R)-2-trimethylsilyl-2-hydroxyl-propionitrile via asymmetric transcyanation of acetyltrimethylsilane with acetone cyanohydrin in an aqueous/organic biphasic system catalyzed by (R)-hydroxynitrile lyase from Prunus japonica seed meal was successfully carried out for the first time. The optimal volume ratio of aqueous to organic phase, buffer pH value and reaction temperature were 15% (v/v), 5.0 and 30°C, respectively, under which both substrate conversion and product enantiomeric excess (ee) were 99%. Silicon atom in the substrate showed great effect on the reaction. Acetyltrimethylsilane was a much better substrate for (R)-hydroxynitrile lyase from Prunus japonica than its carbon analogue. 相似文献
5.
Host specificity of foreign natural enemies are becoming more and more critical in classical biological control programs, as concerns about potential risk from introduced biocontrol agents have been increasing recently. Understanding the insect's fundamental and ecological host ranges is the first step in determining the potential for introduction of an insect to control invasive plants. Japanese knotweed, Fallopia japonica (Houttuyn) Ronse Decraene (Polygonaceae) is an invasive weed in the United States and Europe. A leaf beetle, Gallerucida bifasciata (Coleoptera: Chrysomelidae) is an important natural enemy attacking this plant in Asia. However, its host range records were ambiguous. This study examined the beetle's host specificity through a set of choice and no-choice tests in the laboratory and field in its native China. Gallerucida bifasciata larvae were able to complete development on seven of 87 plant species in larval development tests, while adults fed and oviposited on 10 plants in no-choice tests. Multiple choice tests showed adults strongly preferred Fallopia japonica, Persicaria perfoliata (L.) H. Gross and Polygonum multiflorum Thunb over all other plants. Open field tests and field surveys further revealed that these three species were in its ecological host range. The results of this study suggest that G. bifasciata is a potential promising agent for control of Japanese knotweed in the United States and Europe, although additional host specificity tests and risk assessment should be completed. 相似文献
6.
Sellés-Marchart S Casado-Vela J Bru-Martínez R 《Archives of biochemistry and biophysics》2006,446(2):175-185
Polyphenol oxidase (PPO) has been extracted from both soluble and particulate fractions of loquat fruit (Eriobotrya japonica Lindl. cv. Algerie). The soluble PPO (20% of total activity) was partially purified 3.3-fold after ammonium sulfate fractionation being in its active state. The particulate PPO fraction (80% of total activity) was purified to homogeneity in a latent form being activable by sodium dodecyl sulfate (SDS). The enzyme was purified 40.0-fold with a total yield of 15.3% after extraction by phase partitioning in Triton X-114 followed by three chromatographic steps. The molecular weight was estimated to be about 59.2 and 61.2 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration chromatography, respectively, indicating that latent PPO is a monomer. Latent PPO catalyzed the oxidation of chlorogenic acid (CA) at a rate 50-fold faster than that of 4-tert-butylcatechol (TBC) but the soluble active counterpart only twice. Both PPOs exhibited similar Km values for TBC but Km for CA was 5-fold higher for the latent than for the active soluble PPO. Other kinetic characteristics, including sensitivity to inhibitors, substrate specificity, thermal stability, temperature, and pH profiles, were quite different between both PPOs. These results provide strong evidences that the soluble active and the particulate latent are different forms of PPO in loquat fruit flesh. The results suggest that the major PPO form for the oxidation of CA, leading to enzymatic browning under physiological conditions, is the latent one. 相似文献
7.
A series of ruthenium (II) complexes of formulae trans-[Ru(PPh3)2(L′H)2](ClO4)2 (1), [Ru(bpy)(L′H)2](ClO4)2 (2), [Ru(bpy)2(L′H)](ClO4)2 (3), cis-[Ru(DMSO)2(L′H)2]Cl2 (4), and [Ru(L′H)3](PF6)2 (5) (where L′H = 2-(2′-benzimidazolyl)pyridine) have been synthesized by reaction of the appropriate ruthenium precursor with 1,2-bis(2′-pyridylmethyleneimino)benzene (L). The complexes were characterized by elemental analyses, spectroscopic and electrochemical data. All the complexes were found to be diamagnetic and hence metal is in +2 oxidation state. The molecular structure of trans-[Ru(PPh3)2(L′H)2](ClO4)2 has been determined by the single crystal X-ray diffraction studies. The molecular structure shows that Ru(II) is at the center of inversion of an octahedron with N4P2 coordination sphere. The ligand acts as a bidentate N,N′donor. The electronic spectra of the complexes display intense MLCT bands in the visible region.Cyclic voltammetric studies show quasi-reversible oxidative response at 0.99-1.32 V (vs Ag/AgCl reference electrode) due to Ru(III)/Ru(II) couple. 相似文献
8.
The ditopic ligand 1,2-bis(1-imidazolylmethyl)benzene (1,2-bimb) and its silver(I) complexes [Ag2(1,2-bimb)2](PF6)2 (1) and {[Ag2(1,2-bimb)2]2(SbF6)4}n (2) were prepared and their structures characterized by X-ray crystallography. Both complexes contain the chair-form unit [Ag2(1,2-bimb)2]2+ with Ag(I) linearly coordinated by NIm (Im=1-imidazolyl) from the Im groups of two 1,2-bimb. However, the [Ag2(1,2-bimb)2]2+ units are positioned differently in forming 1D infinite chains through weak argentophilic interactions: linear chains in 1 with the units oriented in same direction are formed via Ag?π interactions, while polymeric chains constructed via Ag?Ag interactions in 2 are observed with the units arranged in alternate directions. Differences in supramolecular structures may be a result of different size of the anions. 相似文献
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11.
Claire Monne Daniel Robic Genevive Campion Richard Bourbouze Alain Rimbault Michle Masure Valrie Langlois Patrick Hemery Philippe Guerin 《Chirality》1996,8(4):300-304
(2S,3S)-3-methyl- and 3-isopropylaspartic acids were synthesized by bioconversion of the corresponding alkylfumarates (mesaconate and 3-isopropylfumarate) using β-methylaspartase from cell-free extracts of Clostridium tetanomorphum. Optically pure (2S,3S)-3-alkylaspartic acids were transformed in several steps to benzyl (3S,4R)-3-alkylmalolactonates without any racemization of the two chiral centers. These optically active α,β-substituted-β-lactones were polymerized by anionic ring opening polymerization yielding optically active semi-crystalline polyesters. 13C NMR analysis of poly[benzyl β-3-isopropylmalate] in CDCl3 has shown that only the iso-type stereosequence is present in the polymer, indicating that the macromolecular chain is constituted by the only units of benzyl β-(2S,3S)-3-isopropylmalate monomer. The polymerization reaction was done without any racemization of the two stereogenic centers as in the case of benzyl (3S,4R)-3-methylmalolactonate. © 1996 Wiley-Liss, Inc. 相似文献
12.
Anna C. G. Hotze Sabrine E. Caspers Dick de Vos Huub Kooijman Anthony L. Spek Anna Flamigni Marina Bacac Gianni Sava Jaap G. Haasnoot Jan Reedijk 《Journal of biological inorganic chemistry》2004,9(3):354-364
The dichlorobis(2-phenylazopyridine)ruthenium(II) complexes, [Ru(azpy)(2)Cl(2)], are under renewed investigation due to their potential anticancer activity. The three most common isomers alpha-, beta- and gamma-[RuL(2)Cl(2)] with L= o-tolylazopyridine (tazpy) and 4-methyl-2-phenylazopyridine (mazpy) (alpha indicating the coordinating Cl, N(pyridine) and Nazo atoms in mutual cis, trans, cis positions, beta indicating the coordinating Cl, N(pyridine) and Nazo atoms in mutual cis, cis, cis positions, and gamma indicating the coordinating Cl, N(pyridine) and Nazo atoms in mutual trans, cis, cis positions) are synthesized and characterized by NMR spectroscopy. The molecular structures of gamma-[Ru(tazpy)(2)Cl(2)] and alpha-[Ru(mazpy)(2)Cl(2)] are determined by X-ray diffraction analysis. The IC(50) values of the geometrically isomeric [Ru(tazpy)(2)Cl(2)] and [Ru(mazpy)(2)Cl(2)] complexes compared with those of the parent [Ru(azpy)(2)Cl(2)] complexes are determined in a series of human tumour cell lines (MCF-7, EVSA-T, WIDR, IGROV, M19, A498 and H266). These data unambiguously show for all complexes the following trend: the alpha isomer shows a very high cytotoxicity, whereas the beta isomer is a factor 10 less cytotoxic. The gamma isomers of [Ru(tazpy)(2)Cl(2)] and [Ru(mazpy)(2)Cl(2)] display a very high cytotoxicity comparable to that of the gamma isomer of the parent compound [Ru(azpy)(2)Cl(2)] and to that of the alpha isomer. These biological data are of the utmost importance for a better understanding of the structure-activity relationships for the isomeric [RuL(2)Cl(2)] complexes. 相似文献
13.
The reaction of with Co(dmgBF2)2(H2O)2 in 1.0 M HClO4/LiClO4 was found to be first-order in both reactants and the [H+] dependence of the second-order rate constant is given by k2obs = b/[H+], b at 25 °C is 9.23 ± 0.14 × 102 s−1. The [H+] dependence at lower temperatures shows some saturation effect that allowed an estimate of the hydrolysis constant for as Ka = 9.5 × 10−3 M at 10 and 15 °C. Marcus theory and the known self-exchange rate constant for Co(OH2)5OH2+/+ were used to estimate an electron self-exchange rate constant of k22 = 1.7 × 10−4 M−1 s−1 for . 相似文献
14.
The synthesis of optically active (R)-2-trimethylsilyl-2-hydroxyl-ethylcyanide by asymmetric trans-cyanation of acetyltrimethylsilane with acetone cyanohydrin in a biphasic system was achieved using (R)-oxynitrilase from loquat seed meal. Diisopropyl ether was the most suitable organic phase among the organic solvents examined. The optimal concentration of acetyltrimethylsilane, concentration of crude enzyme, volume ratio of the aqueous to the organic phase, temperature and the buffer pH value were 14 mM, 61.4 U ml-1, 13% (v/v), 30 °C and 4, respectively. The substrate conversion and the product enantiomeric excess were 95% and 98% under the optimized conditions. Acetyltrimethylsilane was a better substrate of the enzyme than its carbon counterpart.
Revisions requested 24 August 2004; Revisions received 12 November 2004 相似文献
15.
The absolute configuration of (+)-cis-2,3-dihydro-2[(methylamino)methyl]-1-[4-(trifluoromethyl)pheno<y]-1H-indene hydrochloride, the more active enantiomer of a new serotonin inhibitor, was established as 1S,2S. This assignment was based on the application of the benzene sector and chirality rules to the interpretation of the inhibitor's circular dichroism spectrum and the spectra of other related chiral 1-substituted 2,3-dihydro-1H-indenes. © 1993 Wiley-Liss, Inc. 相似文献
16.
Garima Singh Ajai K. Singh John E. Drake M.B. Hursthouse 《Inorganica chimica acta》2005,358(4):912-918
Two tellurium ligands 1-(4-methoxyphenyltelluro)-2-[3-(6-methyl-2-pyridyl)propoxy]ethane (L1) and 1-ethylthio-2-[2-thienyltelluro]ethane (L2) have been synthesized by reacting nucleophiles [4-MeO-C6H4Te−] and [C4H3S-2-Te−] with 2-[3-(6-methyl-2-pyridyl)propoxy]ethylchloride and chloroethyl ethyl sulfide, respectively. Both the ligands react with HgBr2 resulting in complexes of stoichiometry [HgBr2 · L1/L2] (1/4), which show characteristic NMR (1H and 13C{1H}). On crystallization of 1 from acetone-hexane (2:1) mixture, the cleavage of L1 occurs resulting in 4-MeOC6H4HgBr (2) and [RTe+→HgBr2]Br− (3) (where R = -CH2CH2OCH2CH2CH2-(2-(6-CH3-C5H3N))). The 2 is characterized by X-ray diffraction on its single crystal. It is a linear molecule and is the first such system which is fully characterized structurally. The Hg-C and Hg-Br bond lengths are 2.085(6) and2.4700(7) Å. The distance of four bromine atoms (3.4041(7)-3.546(7) Å) around Hg (cis to C) is greater than the sum of van der Waal’s radii 3.30 Å. This mercury promoted cleavage is observed for an acyclic ligand of RArTe type for the first time and is unique, as there appears to be no strong intramolecular interaction to stabilize the cleavage products. The 4 on crystallization shows the cleavage of organotellurium ligand L2 and formation of a unique complex [(EtS(CH2)2SEt)HgBr(μ-Br)Hg(Br)(μ-Br)2Hg(Br)(μ-Br)BrHg(EtS(CH2)2SEt)] · 2HgBr2 (5), which has been characterized by single crystal structure determination and 1H and 13C{1H} NMR spectra. The elemental tellurium and [C4H3SCH2]2 are the other products of dissociation as identified by NMR (proton and carbon-13). The cleavage appears to be without any transmetalation and probably first of its kind. The centrosymmetric structure of 5 is unique as it has [HgBr3]− unit, one Hg in distorted tetrahedral geometry and one in pseudo-trigonal bipyramidal one. The molecule of 5 may also be described as having [(EtSCH2CH2SEt)HgBr]+ [HgBr3]− units, which dimerize and co-crystallize with two HgBr2 moieties. There are very weak Hg?Br interactions between co-crystallized HgBr2 units and rest of the molecule. [Hg(3)-Br(1)/Hg(3)-Br(4) = 3.148(1)/3.216(1) Å]. The bridging Hg?Br distances, Hg(2)-Br(4)′, Hg(2)′-Br(4) and Hg(1)-Br(2), are from 2.914(1) to 3.008(1) Å. 相似文献
17.
Emmanuelle Braud Muriel Duflos Guillaume Le Baut Pierre Renard Bruno Pfeiffer Gordon Tucker 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):253-257
The synthesis and pharmacological evaluation of new 3-(imidazol-4(5)-ylmethylene)-2,3-dihydrobenzo[b]furan-2-ones 8-10 and 3-(3,5-dimethylpyrrol-2-ylmethylene)-2,3-dihydrobenzo[b]furan-2-one 11, analogues of SU-5416, as potential inhibitors of angiogenesis, are reported. Compounds 8 and 11 were prepared by a Knoevenagel reaction starting from 2-hydroxyphenylacetic acid 2 and 4-formylimidazole 5 or 2-formyl-3,5-dimethylpyrrole 7, followed by acid-catalysed cyclodehydration. For compounds 9 and 10, an alternative method was used; it consisted in carrying out the Knoevenagel reaction with the 2,3-dihydrobenzo[b]furan-2-ones 3 and 4. The antiangiogenic activity of these compounds was evaluated in the three-dimensional in vitro rat aortic rings test at 1 μM. At this concentration, compound 11 induced a decrease of angiogenesis comparable to that observed with SU-5416; the vascular density index at 1 μM of 11 and SU-5416 were 30±10 and 22±4% of control, respectively. 相似文献
18.
《Bioscience, biotechnology, and biochemistry》2013,77(11):1991-1992
(S)-1-(2-Naphthyl)ethanol was yielded by immobilized pea (Pisum sativum L.) protein (IPP) from (R, S) 2-naphthyl ethanol (>99% ee, yield; about 50%), in which the (R)-enantiomer was selectively oxidized to 2-acetonaphthone. IPP could be reused consecutively at least three times without any decrease of yield and optical purity. 相似文献
19.
Markus Fessler Sylvia Eller Stephan Haringer Peter Brüggeller 《Inorganica chimica acta》2010,363(9):2001-2008
The novel dimer of the composition [Pt2Cl4(μ-(κP1:κP2-o-MeO-trans-dppen))2] (1) (o-MeO-trans-dppen = 1,2-(bis(o-methoxyphenyl)phosphanyl)ethylene) has been prepared and characterized by a single crystal X-ray structure analysis, NMR spectroscopy, mass spectrometry and elemental analysis. This latter compound undergoes a [2+2] photocycloaddition reaction yielding the tetraphosphane all-trans-1,2,3,4-tetrakis(di(o-methoxyphenyl)phosphanyl)cyclobutane (o-MeO-dppcb). The X-ray structure of the dimeric Ni(II) complex that contains the latter ligand, of the formula [Ni2Cl4(μ-(κP1:κP2:κP3:κP4-o-MeO-dppcb))] (2) reveals that the apical coordination sites of both square pyramidal Ni(II) coordination spheres are occupied by methoxy-oxygen atoms of the ligand. As a consequence, this dimeric Ni(II) complex 2 is prone to a thermally induced regio- and diastereoselective metal-assisted methoxy-group cleavage. The stepwise formed new mono- and bis-phenolate complexes [Ni2Cl3(μ-(κO1,κP1:κP2:κP3:κP4-o-MeO-O-dppcb))] (3) and [Ni2Cl2(μ-(κO1,κP1:κP2:κO2,κP3:κP4-o-MeO-O,O′-dppcb))] (4), respectively, contain the novel chiral tetraphosphane ligands all-trans-1,2,3-tris((di-o-methoxyphenyl)phosphano)-4-((o-methoxy-phenyl)(o-phenolate)phosphano)cyclobutane (o-MeO-O-dppcb) and all-trans-1,2-bis((di-o-methoxyphenyl)phosphano)-3,4-bis((o-methoxyphenyl)(o-phenolate)phosphano)cyclobutane (o-MeO-O,O′-dppcb). Compounds 3 and 4 have been synthesized independently and are also fully characterized by both single crystal X-ray structure analyses, NMR spectroscopy, mass spectrometry and elemental analyses. The conversion of 2 into 3 and then further into 4 has been followed by a variable-temperature 31P{1H} NMR experiment with compound 2 in DMF-d7, revealing that the cleavage of the second methoxy group is kinetically disfavoured. This is in agreement with the X-ray structure analysis of 3, indicating the lack of any methoxy-oxygen atom coordination that could easily induce a further methoxy-group cleavage. o-MeO-O-dppcb and o-MeO-O,O′-dppcb are rare P-stereogenic tetraphosphine ligands and contribute to the synthetic field of new κ3-P,P,O-coordinating phosphanylphenolate ligands that are believed to be important for the SHOP process (SHOP, Shell Higher Olefin Process). 相似文献
20.
Mihoko Itagaki Hiroshi Soejima Ko Ishii Tamizi Sugiyama Yoshiharu Hayashi 《Plant and Soil》2003,255(1):67-75
In a previous study, it was demonstrated that N-(phenethyl)succinamic acid (PESA) derivatives form a new category of root-promoting substances which do not exhibit auxin-like activities, such as stem elongation and leaf epinasty (Soejima et al., 2000 [Plant Cell Physiol. 41s: 197]). In this study, N-[2-(3-indolyl)ethyl]succinamic acid (IESA) and N-[2-(1-naphthyl)ethyl]succinamic acid (NESA) were synthesized, and their biological activities were evaluated. In an adzuki root-promoting assay, IESA and NESA exhibited root-promoting activity equivalent to PESA. In adzuki stem elongation assays, elongation activity was not observed in the stem segments soaked in either an IESA or NESA aqueous solution, whereas the stem segments immersed in Indole-3-acetic acid (IAA) or 1-naphthylacetic acid (NAA) aqueous solution were clearly elongated. In an epinastic bending study, IAA and NAA exhibited leaf epinasty, whereas IESA and NESA did not, suggesting that the IESA and NESA derivatives belong to the same category of root-promoting substances as PESA derivatives and are different from auxin-like substances. In addition, eleven kinds of IESA derivatives and nineteen kinds of NESA derivatives were synthesized, and their root-promoting activities were measured. The activities of methyl ester derivatives were approximately three times higher than that of the acid compounds, with exceptions for some compounds. The partition coefficient (P) between 1-octanol and water for each IESA, NESA, and PESA derivative was measured in order to evaluate the hydrophobicity of their molecules and to determine their structure–activity relationship. The results indicate that the root-promoting activity of the acid compounds was significantly correlated with their hydrophobicity, whereas that of ester derivatives was not correlated. 相似文献