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1.
( ± )-Methyl phaseates were synthesized from ( ± )-4-(6′-acetoxymethyl-2 ′,6′-dimethyl-1′-cyclohexen-1′-y1)-but-3-en-2-one (20), which was prepared from a useful terpenoid building block, ( ± )-2-hydroxymethyl-2,6-dimethyl-1-cyclohexanone (11a and 11b). Photooxidation of the cyclohexadiene intermediate (22), followed by alkaline hydrolysis and methylation, gave four stereoisomers of ( ± )-methyl phaseates: (2Z,4E)-cis form (2), (2E,4E)-cis form (24), (2Z,4E)-trans form (25) and (2E,4E)-trans form (26).  相似文献   

2.
The prochiral sila-ketone acetyldimethyl-(phenyl)silane (1) was reduced enantioselectively into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane [(R)-2] using resting cells of the commercially available yeast Saccharomyces cerevisiae (DHW S-3) as the biocatalyst. The bioconversion was performed on a 2.0-g scale in a 5-1 bioreactor. Starting with a substrate (1) concentration of 0.4 g·1–1, the highest production rate measured for this bioconversion was about 45–55 mol (R)-2·1–1·min–1. After an incubation time of 1 h, all substrate in the medium had been converted, either biocatalytically reduced to (R)-2 or (probably chemically) converted into dimethyl(phenyl)silanol (Me2PhSiOH). After extraction of the cell-free medium with ethyl acetate/dichloromethane and subsequent purification of the extract by Kugelrohr distillation and chromatography on silica gel (medium-pressure liquid chromatography), 800 mg (yield 40%) of the bioconversion product (R)-2 was isolated. As shown by HPLC studies (cellulose triacetate as the chiral stationary phase) and 1H-nuclear magnetic resonance experiments (after derivatization of the bioconversion product with a chiral auxiliary agent), compound (R)-2 was almost enantiomerically pure (> 99% enantiomeric excess).This article is dedicated to Prof. Dr. Fritz Wagner on the occasion of his 65th birthday  相似文献   

3.
Background: It is argued that coastal endemic taxa may evolve in parallel at the periphery of the distributional range of a widespread species.

Aims: We tested this hypothesis for the origins of three peripheral, coastal isolates of Senecio, S. glaucus ssp. glaucus (Israel), S. g. ssp. coronopifolius p.p. (Sicily), and S. hesperidium (Morocco), from widespread S. glaucus ssp. coronopifolius. We also determined the relative roles of selection vs. genetic drift in shaping phenotypic divergence in ssp. glaucus and S. hesperidium, using Lande’s test of neutral morphological change.

Methods: We surveyed morphological and/or allozyme variation in the three peripheral isolates and mainly inland populations of S. g. ssp. coronopifolius.

Results: Genetic data supported independent origins of the coastal taxa from nearby populations of ssp. coronopifolius. These descendant and ancestral populations showed pronounced morphological but weak genetic differentiation. Phenotypic similarities between ssp. glaucus (Israel) and S. hesperidium (Morocco) in plant height and floral traits may have resulted from parallel divergent selection from ssp. coronopifolius, though drift remains an alternative cause in S. hesperidium.

Conclusions: Our results indicate parallel ecotype formation and (sub)speciation in Senecio in which primarily selective vs. neutral determinants promoted the recurrent origin of coastal types in, respectively, Israel and Morocco.  相似文献   

4.
Two new species in the acuminata group of subgenus Tipula (Lunatipula), Tipula (Lunatipula) oosterbroeki sp. n. and T (L) jaroslavi sp. n., were described and illustrated from Southwest part of Asian Turkey.  相似文献   

5.
Two effective cytochrome P450 (CYP) inhibitors were isolated from tarragon, Artemisia dracunculus. Their structures were spectroscopically identified as 2E,4E-undeca-2,4-diene-8,10-diynoic acid isobutylamide (1) and 2E,4E-undeca-2,4-diene-8,10-diynoic acid piperidide (2). Both compounds had dose-dependent inhibitory effects on CYP3A4 activity with IC50 values of 10.0 ± 1.3 µM for compound 1 and 3.3 ± 0.2 µM for compound 2, and exhibited mechanism-based inhibition. This is the first reported isolation of effective CYP inhibitors from tarragon (Artemisia dracunculus) purchased from a Japanese market.  相似文献   

6.
First enantioselective synthesis of S-(-)-1-[3-(4-tert-butylphenyl)-2-methyl]propyl-cis-3,5-dimethylmorpholine (6), biologically active enantiomer of the systematic fungicide fenpropimorph, is reported. It comprises reacting 4-tert-butylbenzylbromide with methyldiethylmalonate, decarbethoxylation of 2 into racemic 3-(4-tert-butylphenyl)-2-methylpropionic acid ethylester (3) in DMSO in the presence of alkali, then Pseudomonas sp. lipase catalyzed kinetic resolution of racemic 3 into S-(+)-acid (4), base-catalyzed racemization and recycling of the R-(-)-ester 3, acylation of cis-3,5-dimethylmorpholine, and final reduction of the intermediary amide 5 to provide enantiomerically pure S-(-)-6.  相似文献   

7.
Two arylderivatives, 3a-Acetoxy-5H-pyrrolo(1,2-a) (3,1)benzoxazin-1,5-(3aH)-dione 3 and cis-N-p-Acetoxy-phenylisomaleimide 4, were synthesized from anthranilic acid and para-aminophenol, respectively. The inhibitory effects of these compounds on acetylcholinesterase (AChE) activity were evaluated in vitro as well as by docking simulations. Both compounds showed inhibition of AChE activity (Ki = 4.72 ± 2.3 μM for 3 and 3.6 ± 1.8 μM for 4) in in vitro studies. Moreover, they behaved as irreversible inhibitors and made π–π interaction with W84 and hydrogen bonded with S200 and Y337 according to experimental data and docking calculations. The docking calculations showed ΔG bind (kcal/mol) of ? 9.22 for 3 and ? 8.58 for 4. These two compounds that can be use as leads for a new family of anti-Alzheimer disease drugs.  相似文献   

8.
Casimirella Hassler (1913) is accepted and Humirianthera Huber (1914) considered a synonym. Casimirella diversifolia and C. lanata from Brazil are described as new species. Casimirella ampla (Miers) based on Leretia ampla Miers, C. crispula (Howard) based on Humirianthera crispula Howard, and C. rupestris (Ducke) based on Humirianthera rupestris Ducke are new combinations.  相似文献   

9.
Abstract

Synthesis, absolute configuration and antiviral activity of enantiomeric antiviral agents (R)-(-)- and (S)-(+)-synadenol (2 and 3a) are described.  相似文献   

10.
A list of 285 species of Sarcophagidaе in the Middle East countries is presented with distributional data, including Bahrain (3 species), Cyprus (46), Egypt (both African and Asian parts) (114), Iran (83), Iraq (17), Israel (113), Jordan (14), Kuwait (3), Lebanon (13), Oman (2), Gaza Strip (5), Palestinian Authority (42), Quatar (1), Saudi Arabia (37), Syria (42), Turkey (both European and Asian parts) (157), United Arab Emirates (14) and Yemen (15). Three new synonyms are established: Blaesoxipha delilah Lehrer, 2006 = Agriella setosa Salem, 1938, syn. n.; Blaesoxipha nahaliana Lehrer, 2008 = Blaesoxipha popovi Rohdendorf, 1937, syn. n.; and Liosarcophaga daccanella Lehrer, 2008 = Liosarcophaga (s. str.) dux (Thomson, 1869), syn. n. Four new combinations for species names are proposed: Liopygia (Engelisca) adhamae (Lehrer & Abou-Ziad, 2008), comb. n.; Liosarcophaga (s. str.) pedestris (Villeneuve, 1910), comb. n.; Liosarcophaga (Pandelleisca) theodori (Lehrer, 1998), comb. n., and Liosarcophaga (Pharaonops) tewfiki (Salem, 1940), comb. n.  相似文献   

11.
Five new genera, Turononemonyxn. gen. (type species: Turononemonyxsamsonovin. sp.) (Nemonychidae: ? Cretonemonychinae: ? Cretonemonychini), Falsotanaosn. gen. (type species: Falsotanaos convexusn. sp.), Pretanaosn. gen. (type species: Pretanaosocularisn. sp.), Longotanaosn. gen. (type species: Longotanaosrasnitsynin. sp.) from Brentidae: Apioninae: Tanaini) and Turonerirhinusn. gen. (type species: Turonerirhinuskaratavensisn. sp.) from Curculionidae (Erirhininae: Erirhinini), and seven new species, Falsotanaosconvexusn. sp., Paratanaos samsonovin. sp., Pretanaos ocularisn. sp., Longotanaos rasnitsynin. sp., Turonerirhinus karatavensisn. sp., Turonerirhinuspunctatusn. sp. and Turonerirhinus poinarin. sp., are described from Kzyl-Dzhar locality (Kazakhstan, Upper Cretaceous, Turonian).http://www.zoobank.org/urn:lsid:zoobank.org:pub:13E0316E-C229-471A-90AA-2D71253B12F9  相似文献   

12.
In this study, a series of novel 2-alkyl(aryl)-quinazolin-4(3H)-thiones, 2-R-(quinazolin-4(3H)-ylthio)carboxylic acids and amides were synthesized and evaluated for antimicrobial and anticancer activities. Their structure was confirmed by elemental analysis and spectral data (FT-IR, LC-MS, 1H-NMR). Antimicrobial activity was tested in vitro against Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, Candida albicans and NCI in vitro preliminary anticancer activity against nine different cancer types. The most active antibacterial and antifungal compounds were: 2.1, 2.2 and 2.4. The introduction of the carboxylic acid or amide residue into the fourth position of quinazolin-4(3H)-thione resulted in the absence of antimicrobial activity. Substance 3.8 inhibited renal cancer UO-31 line and 2.18 – leukemia CCRF-CEM. The results of in silico molecular docking for DHFR and CK2 kinase had no correlation with in vitro properties, proposing the presence of other biological activity pathways.  相似文献   

13.
A series of new N′-[N-(2,3,4-tri-O-acetyl-β-d-xylopyranosyl)thiocarbamoyl]-2-[(1-aryl-1H-tetrazol-5-yl)sulfanyl]acetohydrazides 5a5e were synthesized rapidly in high yields from 2-(1-aryl-1H-tetrazol-5-ylsulfanyl)acetohydrazides 3a3e and 2,3,4-tri-O-acetyl-β-d-xylopyranosyl isothiocyanate 4, then 5a5e were converted to a series of new 5-(1-aryl-1H-tetrazol-5-ylsulfanylmethyl)-N-(2,3,4-tri-O-acetyl-β-d-xylopyranosyl)-1,3,4-oxadiazole-2-amines 6a6e and 5-(1-aryl-1H-tetrazol-5-ylsulfanylmethyl)-N-(2,3,4-tri-O-acetyl-β-d-xylopyranosyl)-1,3,4-thiadiazole-2-amines 7a7e, respectively under mercuric acetate/alcohol system or acetic anhydride/phosphoric acid system, then deacetylated in the solution of CH3ONa/CH3OH. All of the novel compounds were characterized by IR, 1H NMR, 13C NMR, MS and elemental analysis. The structures of compounds 2e, 3e, 5a and 5c have been determined by X-ray diffraction analysis. Some of the synthesized compounds displayed PTP1B inhibition and microorganism inhibition.  相似文献   

14.
 Salmon sperm DNA platination has been conducted under strictly pseudo-first-order conditions with cisplatin (1) and rac-{(1S,2S,4S)-exo-2-(aminomethyl)-2-amino-7-bicyclo[2.2.1]heptane}dichloroplatinum(II) (2). An aquation step first occurs for both complexes, with the rate constants k 1 = 1.12(0.02)×10–4 s–1 and 1.47(0.02)×10–4 s–1 respectively for 1 and 2 at 37  °C, values in agreement with those previously reported. It is followed by the actual platination step whose second-order rate constant has been determined for the first time by physicochemical techniques. The values for 1 and 2 respectively are: k 2 = 2.08(0.07) M–1 s–1 and 3.9(0.4) M–1 s–1. These kinetic data are discussed in the context of a comparison of several biological properties of the two complexes. Received: 15 May 1998 / Accepted: 26 June 1998  相似文献   

15.
Iron(II) dichloride complexes bearing 2-(methyl-substituted 1H-benzoimidazol-2-yl)-6-(1-aryliminoethyl)pyridines (Fe1Fe6) or 2-(chloro-substituted 1H-benzoimidazol-2-yl)-6-(1-aryliminoethyl)pyridines (Fe7Fe12) were synthesized and characterized by FT-IR and elemental analysis. Single crystal X-ray crystallographic analyses revealed that complexes Fe2 and Fe3 possessed a distorted square-pyramidal geometry at iron. Upon activation with either MAO or MMAO, all iron pro-catalysts showed good activities toward ethylene oligomerization with high selectivity for α-olefins and high K values. The influence of the reaction conditions and the nature of the ligands on the catalytic performance of these iron complexes were investigated.  相似文献   

16.
17.
The Malagasy fauna includes two genera of Philopotaminae: Wormaldia McLachlan 1865 and an endemic new genus, Ranarijaodes n. gen. The Malagasy and African (sensu stricto) lineages of Wormaldia are distinct. Apomorphic characters (the shape of the phallic apparatus for the African species and the splitting of the median lobe of the tenth tergite for the Malagasy species) confirm their separation. New captures are reported for two of the four previously known species of Wormaldia. Seven new species are described: Wormaldia ambahibeae n. sp., W. faharoa n. sp., W. fahatelo n. sp., W. randriamasimananai n. sp., W. fahefatra n. sp., W. legrandi n. sp. and W. fahadimy n. sp. Ranarijaodes n. gen. is close to Dolophilodes Ulmer 1909. It is described for the three new species Ranarijaodes fiana n. sp., R. angapi n. sp. and R. atsimo n. sp. The 14 Malagasy species of Philopotaminae are endemics of the island. Their geographical distributions and ecological preferences are described and discussed.  相似文献   

18.
Abstract

Limonium guigliae, from the island of Soqotra (Yemen) is described. This new species, close to L. paulayanum differs from it by its size, flower morphology and ecology.  相似文献   

19.
This paper reports on a total synthesis of racemic δ-cadinene (2), which had been obtained previously in optically active form by acid-catalyzed cyclization of (–)-germacrene D. The Robinson annelation using cyclohexenone enamine (12) proceeded stereoselectively to form δ-cadinenone (3), whose oxygen was removed by the thioketal–Raney Ni method to produce δ-cadinene.  相似文献   

20.
Abstract

In this study, four Co(III)-, Cu(II)-, Zn(II)- and Pd(II)-based potent antibacterial complexes of formula K3[Co(ox)3]·3H2O (I), [Cu(phen)2Cl]Cl·6.5H2O (II), [Zn(phen)3]Cl2 (III) and [Pd(phen)2](NO3)2 (IV) (where ox is oxalato and phen is 1,10-phenanthroline) were synthesized. They were characterized by elemental analysis, molar conductivity measurements, UV–vis, Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance (1H-NMR) techniques. These metal complexes were ordered in three combination series of I+II, I+II+III and I+II+III+IV. Antibacterial screening for each metal complex and their combinations against Gram-positive and Gram-negative bacteria revealed that all compounds were more potent antibacterial agents against the Gram-negative than those of the Gram-positive bacteria. The four metal complexes showed antibacterial activity in the order I > II > III > IV, and the activity of their combinations followed the order of I+II+III+IV > I+II+III > I+II. The DNA-binding properties of complex (I) and its three combinations were studied using electronic absorption and fluorescence (ethidium bromide displacement assay) spectroscopy. The results obtained indicated that all series interact effectively with calf thymus DNA (CT-DNA). The binding constant (Kb), the number of binding sites (n) and the Stern–Volmer constant (Ksv) were obtained based on the results of fluorescence measurements. The calculated thermodynamic parameters supported that hydrogen bonding and van der Waals forces play a major role in the association of each series of metal complexes with CT-DNA and follow the above-binding affinity order for the series.

Communicated by Ramaswamy H. Sarma  相似文献   

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