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1.
Hilmer Sørensen 《Phytochemistry》1976,15(10):1527-1529
2(S),2′(S)-N6-(2′-Glutaryl)lysine (l-saccharopine) and 2(S)-2-aminoadipic acid have been isolated from Reseda odorata. When traditional isolation procedures are used l-pyrosaccharopine (5(S),5′(S)-N-(5′-amino-5′-carboxy-pentyl)-2-pyrrolidone-5-carboxylic acid) is formed from l-saccharopine by lactamisation. The degree of lactamisation during various isolation steps has been studied, The amino acids were identified by IR and PMR spectroscopy and the configurations established by enzymic and polarimetric analyses. The contents of saccharopine and 2-amino-adipic acid have been determined relative to the total nitrogen content at various stages in the growth cycle of R. odorata.  相似文献   

2.
The chromosome numbers ofVeronica beccabunga subsp.abscondita (2n=18),V. anagallis-aquatica subsp.lysimachioides (2n=18),V. anagallis-aquatica subsp.michauxii (2n=36), and of a presumable hybridV. poljensis × V. anagalloides (2n=36) are new for the relevant taxa. — A new number was found forV. anagalloides subsp.heureka (2n=18). The other counts, ofV. scardica (2n=18),V. anagalloides subsp.anagalloides (2n=18), andV. anagallis-aquatica subsp.oxycarpa (2n=36) agree with earlier findings.—Data from the literature have been critically evaluated, in some cases the relevant vouchers have been checked and, where needed, the original determinations have been revised. For several taxa, comments concerning their systematics and remarks on their distribution in Turkey are given.  相似文献   

3.
During the present study, 360 populations of 174 species belonging to 82 genera and 23 families of dicots have been cytologically worked out from different localities of District Kangra (Himachal Pradesh) between 550 and 3,800 m altitude. As many as 10 species including Berberis ceratophylla (2n = 28), Caltha alba (2n = 32), Corydalis meifolia (2n = 16), C. thyrsiflora (2n = 16), Impatiens reidii (2n = 14), Indigofera hamiltonii (2n = 16), Potentilla thomsonii (2n = 14), Sedum trifidum (2n = 36), Stellaria semivestita (2n = 26) and Viola canescens (2n = 12) have been cytologically worked out for the first time at world level. New intraspecific diploid cytotypes have been recorded in 11 species while new intraspecific tetraploid cytotypes are noticed in 15 species. B-chromosomes have also been reported in 3 species viz. Anemone obtusiloba, Clematis grata and Ranunculus diffusus for the first time at world level. The species of the area are active state of evolution, depicting heterogeneity in chromosome numbers involving polyploidy (48 species, 28.18 %) as well as irregular meiotic behavior. The meiotic abnormalities have been witnessed in 69 species (39.65 %) showing different types of irregularities such as cytomixis, interbivalant connections, unoriented bivalents, chromatin stickiness, chromosomal laggards and bridges as well as abnormal microsprogenesis. All these meiotic abnormalities lead to reduced pollen fertility and formation of variable sized pollen grains in most of these species.  相似文献   

4.
Using combined gas chromatography-mass spectrometry, some 55 constituents of Iridomyrmex humilis have been characterized on the basis of total extraction data, and of data reported for the separate extraction of heads, thoraxes and gasters of this ant. Twenty-seven hydrocarbons—normal, unsaturated, and branched—have been identified. Of these the alkenes (5), (11), (17), and (22) are located primarily, if not wholly, in the heads. Four pyrazines (1), (3), (12), and (21) are present in the heads. The terpenoid, iridomyrmecin (4) is the known major extractive of I. humilis; dolichodial (2) and four related cyclopentanoid monoterpene acids (103), (104), (105), and (106) are now reported from the gasters. The iridoids (2) and (4) are constituents of the anal gland. Three esters—isopropyl myristate, methyl palmitate, and dibutyl phthalate—have been characterized from the total extract. Of these the dibutyl phthalate, mainly found in the thoraxes and gasters, is possibly an artifact. Twelve fatty acids, normal, unsaturated, and branched, and two chlorinated phenols, have also been identified from each extract. The chlorinated phenols are possibly artifacts.  相似文献   

5.
The complexes dichloro[2-(phenylselanyl)ethanamine]platinum(II), dichloro[2-(benzylselanyl)ethanamine]platinum(II) and dichloro(O-methylselenomethionine)platinum(II) have been prepared and the structure of dichloro(O-methylselenomethionine)platinum(II) has been determined by single crystal X-ray diffraction. The Pt(II) is in a square planar environment and is coordinated by two cis chloride ligands and a chelating O-methylselenomethionine ligand. The cytotoxicities of the compounds have been assessed in the human cell lines HeLa and K562 and they are at least threefold less toxic than cisplatin in both cell lines.  相似文献   

6.
《Inorganica chimica acta》1989,162(1):143-149
Two complexes, SnCl2(bzac)2 [Hbzac = benzoylacetone] and SnCl2(bzbz)2 [Hbzbz = dibenzoylmethane], have been prepared and characterised by analytical, infrared and Mössbauer studies. In addition, the X-ray crystal structure of SnCl2(bzbz)2 has been determined. The crystals are orthorhombic, space group Pbca with cell parameters a=18.767(9), b=17.611(8), c=16.563(8) Å. A total of 2116 reflections with I/σ(I)⩾3 gave R=3.0%. The tin is coordinated to two cis-chlorine and four oxygen atoms from the dibenzoylmethanato ligands in an approximately octahedral arrangement. The bond distances in the tin coordination sphere are SnCl 2.335(2) and 2.344(2) Å and SnO 2.062(4), 2.074(4), 2.063(4) and 2.063(4) Å and the ClSnCl angle is 95.1(1)°. The results of anti-tumour tests on these complexes are given and attempts are made to correlate the anti-tumour activity of SnCl2(bzbz)2 with its structure.  相似文献   

7.
《Inorganica chimica acta》1987,133(1):161-166
Coordination polymers of lanthanum(III), praseodymium(III), neodymium(III), samarium(III), dysprosium(III) and holmium(III) with 1,4-dihydroxyanthraquinone have been synthesized and characterised. Their magnetic moments, infrared spectra and electronic spectra have been studied to establish their structure. All the polychelates are amorphous, dark coloured powders, insoluble in common organic solvents and sparingly soluble in dimethylformamide. Nephelauxetic ratio (β), covalency factor (b1/2), etc. have been evaluated wherever possible. Thermogravimetric studies (TGA) indicate a higher decomposition temperature of polychelates than the parent ligand. A.c.-conductivity, dielectric constant (ϵ′), dielectric loss (ϵ″), all at various frequencies, as well as d.c.-conductivity of the prepared polychelates, are reported. The analytical data are suggestive of a 2:3 metal-ligand stoichiometry in the polychelates.  相似文献   

8.
Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used throughout the world. Caffeic acid, chlorogenic acid (5-O-caffeoylquinic acid), caftaric acid (2-O-caffeoyltartaric acid), cichoric acid (2, 3-O-dicaffeoyltartaric acid), cynarin, and echinacoside are some of the important CADs which have varied pharmacological activities. The concentrations of these bioactive compounds are species specific and also they vary considerably with the cultivated Echinacea species due to geographical location, stage of development, time of harvest, and growth conditions. Due to these reasons, plant cell and organ cultures have become attractive alternative for the production of biomass and caffeic acid derivatives. Adventitious and hairy roots have been induced in E. pupurea and E. angustifolia, and suspension cultures have been established from flask to bioreactor scale for the production of biomass and CADs. Tremendous progress has been made in this area; various bioprocess methods and strategies have been developed for constant high-quality productivity of biomass and secondary products. This review is aimed to discuss biotechnological methods and approaches employed for the sustainable production of CADs.  相似文献   

9.
《Inorganica chimica acta》1986,114(2):111-117
Some uranyl(VI) complexes with new acyclic and cyclic Schiff base compartmental ligands have been prepared and characterized. The ligands have been obtained by reaction of 4-chloro-2,6-diformylphenol and polyamines of the type NH2(CH2)2X (CH2)2NH2 (X= NH, S). The structure of the uranyl(VI) complex with the ligand 1,7,15,21-tetra- aza-4,18-dithia-11,25-dichloro 8,22-bis-metadiphenyl cyclophane-gb-7,14,21,28 has been determined by X-ray crystallography. The compound crystallizes in the orthorhombic space group Pbca with eight formula units in a cell of dimensions a = 26.654(3), b = 22.871(3), c = 8.875(5) Å. The structure was solved by standard methods and refined by full- matrix least squares to the conventional R index of 4.6% for 2678 independent observed reflexions. Five donor atoms (including sulphur) of the ligand are equatorially bonded to the uranyl group to form discrete monomeric molecules with the seven-coordinated metal in the usual distorted pentagonal bipyramidal coordination geometry. Selected bond distances are: UO (equatorial), 2.22(1) and 2.25(1) Å; UN, 2.60(1) and 2.59(1) Å; US, 3.018(4) Å.  相似文献   

10.
Two new naphthalene derivatives and three naphthoquinones have been found in the root bark of Ventilago maderaspatana. Their structures are 2-acetyl-6,7-dimethoxy-3-methyl-1,8-methylenedioxynaphthalene (ventilaginone) and 1,3-dihydro-6,9-dihydroxy-7,8-dimethoxy-1-methylnaphtho[2,3-c]furan-3-one (ventilagol), 2(2′-acetoxypropyl)-3-hydroxy-5,7,8-trimethoxy-1,4-naphthoquinone (maderone), cordeauxione and isocordeauxione. The root bark of V. calyculata contains 2-methoxystypandrone and 1-hydroxy-6-methoxy-3-methylxanthone-8-carboxylic acid (calyxanthone).  相似文献   

11.
The adipocytes synthesize and store triglycerides as lipid droplets surrounded by various proteins and phospholipids at its surface. Recently, the molecular basis of some of the genetic syndromes of lipodystrophies has been elucidated and some of these genetic loci have been found to contribute to lipid droplet formation in adipocytes. The two main types of genetic lipodystrophies are congenital generalized lipodystrophy (CGL) and familial partial lipodystrophy (FPL). So far, three CGL loci: 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2), Berardinelli–Seip Congenital Lipodystrophy 2 (BSCL2) and caveolin 1 (CAV1) and four FPL loci: lamin A/C (LMNA), peroxisome proliferator-activated receptor γ (PPARG), v-AKT murine thymoma oncogene homolog 2 (AKT2) and zinc metalloprotease (ZMPSTE24), have been identified. AGPAT2 plays a critical role in the synthesis of glycerophospholipids and triglycerides required for lipid droplet formation. Another protein, seipin (encoded by BSCL2 gene), has been found to induce lipid droplet fusion. CAV1 is an integral component of caveolae and might contribute towards lipid droplet formation. PPARγ and AKT2 play important role in adipogenesis and lipid synthesis. In this review, we discuss and speculate about the contribution of various lipodystrophy genes and their products in the lipid droplet formation.  相似文献   

12.
The contents of amino acids and peptides have been investigated in seeds of Fagus silvatica L. (beechnuts). In addition to the common amino acids, the following compounds have been isolated and identified: 4-hydroxyproline (probably the cis-l-isomer), N5-acetylornithine, 3-(2-furoyl)-l-alanine, methionine sulfoxide (probably an artefact), pipecolic acid (probably partially racemized d-isomer), l-willardiine (with a small amount of the d-isomer), N-(3-amino-3-carboxypropyl)azetidine-2-carboxylic acid, N-[N-(3-amino-3-carboxypropyl)-3-amino-3-carboxypropyl]azetidine-2-carboxylic acid, 2(S),5(S),6(S)-5-hydroxy-6-methylpipecolic acid, 2(S),5(R),6(S)-5-hydroxy-6-methylpipecolic acid, γ-glutamylalanine, γ-glutamylglutamic acid, γ-glutamylisoleucine, γ-glutamylleucine, γ-glutamylmethionine sulfoxide (probably an artefact), γ-glutamylphenylalanine, γ-glutamyltyrosine, γ-glutamylvaline, glutathione, γ-glutamylwillardiine, and γ-glutamylphenylalanylwillardiine. γ-Glutamylphenylalanine and willardiine are the dominating components of the amino acid fraction.The isolations were performed by use of ion exchange chromatography, taking advantage of the different pK-values of the amino acids, mainly on acid resins in the 3-chloropyridinium form with aq. 3-chloropyridine as eluant and on basic resins in the acetate form with aqueous acetic acid as eluant. These methods in combination with preparative paper chromatography have permitted the isolation and identification of compounds present in amounts as low as 1/6000 of the dominant ninhydrin-reactive component. The implications of the occurrence of this large variety of compounds in the Fagaceae are briefly discussed.  相似文献   

13.
Chromosome numbers of twenty taxa, almost all of them Iberian endemics, of the generaTeucrium, Sideritis, Thymus andSalvia are reported. New chromosome numbers are given for the following taxa:Teucrium homotrichum (2n=78),T. hifacense (2n=26),T. rivasii (2n=26),T. rivas-martinezii (2n=26),Sideritis edetana (2n=30),S. murgetana subsp.littoralis (2n=28), and the hybridS. xviciosoi (2n=27). The first count on Iberian material forSalvia pratensis (2n=18) is reported. Chromosome numbers have been confirmed for the rest of the taxa studied on material from SE Spain. Karyotype analyses and taxonomic remarks are included.  相似文献   

14.
The taxonomic arrangement and the karyological analysis of 166 populations ofLeucanthemum demonstrates the existence of 5 taxa for Czechoslovakia; they are grouped provisionally intoL. rotundifolium (W. K.) DC. (2n = 18) and the polyploid complexL. vulgare Lam. with “subsp.vulgare” (2n = 18), “subsp.alpicola” (2n = 18), “subsp.ircutianum” (2n = ± 36) and “subsp.pannonicum” (2n = ± 54). B-chromosomes have not been traced in diploids but have turned up in great numbers in tetraploid (21%) and hexaploid populations (20%). Their presence is not apparent from external characters. Diploids and polyploids evidently are selfsterile.  相似文献   

15.
The miracidia of four human blood flukes, Schistosoma haematobium, S. intercalatum, S. mansoni and S. japonicum, have been studied by means of the scanning electron microscope (SEM). Differences have been observed in their respective dimensions, in the configuration of their terebratoria (apical papillae), in the shape of the epidermal plates, and in the distribution of the sensory receptors. The most evident differences have been noticed on the terebratoria where two main patterns of organization of the anastomosing membrane foldings have been described: (1) a ‘rosette’ pattern observed in S. haematobium and S. intercalatum and (2) a ‘honeycomb’ pattern in S. mansoni and S. japonicum. The structure and the taxonomic importance of these morphological features are analysed.  相似文献   

16.
《Inorganica chimica acta》1988,144(2):205-211
Two (1:2) silver monophosphine complexes have been studied by X-ray diffraction methods and in solution by P NMR spectroscopy. Both are monomeric and tricoordinated in the solid state but one of them, the perchlorate compound, is probably associated as a dimer species in solution from the lower 1J(107Ag31P) value when compared to the nitrate analogue. Previous structural correlations found in other silver-phosphine complexes have been confirmed for these new compounds. Thus, larger PAgP bond angles are associated with shorter AgP bond distances, longer Aganion bond distances and lower Lewis basicity of the anions. Selected structural data are: PAgP bond angle of 139.04(9)°, AgP bond lengths of 2.440(3) and 2.445(3) Å for the nitrate complex and 147.34(3)°, 2.429(1) Å and 2.432(1) Å, for the perchlorate one. J(107Ag31P) is 457 Hz and 447 Hz, respectively. The complexes are triclinic, Z = 2, with the parameters: a = 9.258(2), b = 9.828(2), c = 23.385(5) Å, α = 94.73(2)°, β = 96.35(2)°, γ = 116.42(1)° (nitrate) and a = 9.505(2), b = 9.790(2), c = 23.667(6) Å, α= 99.03(2) β = 95.44(2) γ = 115.97(1)° (perchlorate).  相似文献   

17.
The N-acetylation polymorphisms of volunteers from the Moscow population analyzed by phenotyping and genotyping have been compared. The ratios between the proportions of fast acetylators (FAs) and slow acetylators (SAs) estimated by phenotyping and genotyping do not differ significantly from each other (47 and 44%, respectively). The absolute acetylation rate widely varies in both FAs and SAs. The NAT2 genotype and allele frequencies in the population sample have been calculated. The most frequent alleles are NAT2*4 (a “fast” allele), NAT2*5, and NAT2*6 (“slow” alleles); the most frequent genotypes are NAT2*5/*5, NAT2*4/*6, and NAT2*4/*5. Comparative analysis of N-acetylation polymorphism estimated by phenotyping and genotyping in the same subjects has shown a complete concordance between the phenotype and genotype in only 62 out of 75 subjects (87%). Comparative characteristics and presumed applications of the two approaches (quantitative estimation of acetylation rate and qualitative determination of the acetylator genotype) to the identification of individual acetylation status are presented.  相似文献   

18.
Analysis of F2, F5 and MTHFR genes SNPs allelic variants in population of Ukraine. Polymorphic variants were analyzed in 172 unrelated individuals using PCR followed by RFLP analysis. Following genotypes have been identified: GG (97%), GA (3%) for F2 gene G20210A SNP, GG (96.5%), GA (3.5%) for F5 gene G1691A SNP and CC (49.5%), CT (43%), TT (7.5%) for MTHFR gene C677T SNP. Following combined genotypes have been detected. We observed 1.7% heterozygous carriers of MTHFR gene 677T SNP which were heterozygous for one of the alleles of F5 1691A or F2 20210A genes. On the other hand, the 7.5% MTHFR gene 677T SNP homozygous individuals carried wild type alleles only of F5 and F2 genes. None of the individuals was carrying F5 1691 A and F2 20210A genes polymorphic variants simultaneously. The data about F2, F5 and MTHFR genes SNPs allelic frequencies in the population of Ukraine have been obtained. Thus, distribution of F2, F5 and MTHFR genotypes based on analysis of SNP in those three genes simultaneously has been detected.  相似文献   

19.
The preparations are reported of the ‘extended reach’ ligand N,N-o-phenylene-dimethylenebis(pyridin-4-one) (o-XBP4) and of a range of its metal complexes with Mn(II), Co(II), Ni(II), Cu(II) and Zn(II), two of which have been shown by X-ray studies to have polymeric structures. In the compound [Mn(o-XBP4)(H2O)2(NO3)](NO3) the o-XBP4 ligands link ‘Mn(H2O)2(NO3)’ units into chains which are then cross-linked into sheets by the bridging action of the coordinated nitrate. In [Cu(o-XBP4)(NO3)2] chains are also formed by the bridging action of the o-XBP4 ligands but here they simply pack trough-in-trough with no nitrate cross-linking. X-band EPR spectra are reported for these and the other Mn and Cu compounds as are relevant spectroscopic results for the other complexes.  相似文献   

20.
Complexes of Zn(II), Cu(II) and Co(II) with either N-(2-methylpyridyl)-3-thienyl-alkyl-carboxamide or N-(2-pyridyl)-3-thienylalkyl-carboxamide groups have been prepared and characterized. Crystal structures of ten new complexes are reported and discussed. N-(2-Methylpyridyl)-3-thienyl-alkyl-carboxamide exhibits both uni- and bidentate behavior. With all ligands, bidentate complexation is through the carbonyl oxygen and pyridine nitrogen atoms (O, N) and the amide nitrogen atom remains protonated. The electrochemical behavior and the infrared spectra of selected complexes are discussed.  相似文献   

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