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1.
Infection by Macrophonina phaseolina was substantially reduced following treatment of sunflower and mungbean seeds with Trichoderma harzianum, Gliocladium virens, Paecilomyces lilacinus or Streptomyces sp. which gave promising control of charcoal rot disease. Treatment of mungbean seeds with Rhizobium meliloti also gave good disease control.  相似文献   

2.
2-(6-Chloropurinyl)-3-benzoyloxymethylcyclobutanone can be prepared by reaction of 6-chloropurine with 3-benzoyloxymethyl-2-bromocyclobutanone. The N-alkylation gave both N-9 and N-7 regioisomers. Both regioisomers upon hydride reduction followed by aminolysis gave the corresponding adenine nucleoside analogues. However, the N-7 series led to the hypoxanthine analogues as byproducts.  相似文献   

3.
The intramolecular cyclization of O-tosyl derivatives of dithioacetals of d-ribose, d-arabinose, and d-glucose was investigated. p-Toluenesulfonylation of d-glucose diethyl dithioacetal gave 3,6-anhydro-d-glucose diethyl dithioacetal. Variously substituted 5-O-tosyl-d-glucose dibenzyl dithioacetals gave derivatives of either 2,5-anhydro-l-idose dibenzyl dithioacetal, benzyl 1,5-dithio-l-idopyranoside, or l-idose dibenzyl dithioacetal. Likewise, 4-O-tosyl-d-glucose dibenzyl dithioacetal derivatives gave benzyl 1,4-dithio-d-galactofuranoside derivatives.  相似文献   

4.
-threo-2,3-Hexodiulosono-1,4-lactone 2-(arylhydrazones) (2) were prepared by condensation of dehydro- -ascorbic acid with various arylhydrazines. Reaction of 2 with hydroxylamine gave the 2-(arylhydrazone) 3-oximes (3). On boiling with acetic anhydride, 3 gave 2-aryl-4-(2,3-di-O-acetyl- -threo-glycerol-l-yl)-1,2,3-triazole-5-carboxylic acid 5,41-lactones (4). On treatment of 4 with liquid ammonia, 2-aryl-4-( -threo-glycerol-l-yl)-1,2,3-triazole-5-carboxamides (5) were obtained. Acetylation of 5 with acetic anhydride-pyridine gave the triacetates, and vigorous acetylation with boiling acetic anhydride gave the tetraacetyl derivatives. Periodate oxidation of 5 gave the 2-aryl-4-formyl-1,2,3-triazole-5-carboxamides (8), and, on reduction, 8 gave the 2-aryl-4-(hydroxymethyl)-1,2,3-triazole-5-carboxamides, characterized as the monoacetates and diacetates. Controlled reaction of 2 with sodium hydroxide, followed by neutralization, gave 3-( -threo-glycerol-l-yl)-4,5-isoxazolinedione 4-(arylhydrazones), characterized by their triacetates. Reaction of 2 with HBr-HOAc gave 5-O-acetyl-6-bromo-6-deoxy- -threo-2,3-hexodiulosono-1,4-lactone 2-(arylhydrazones); these were converted into 4-(2-O-acetyl-3-bromo-3-deoxy- -threo-glycerol-l-yl)-2-aryl-1,2,3-triazole-5-carboxylic acid 5,41-lactones on treatment with acetic anhydride-pyridine.  相似文献   

5.
Abstract

Reaction of the silylated 6-azauracil (2) with 2-acetamido-1,3,4,6-tetra-O-acetyl-2-deoxy-D-glucose (3) gave 1-(2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-ß-D-glucopyranosyl)-6-azauracil (4), which gave the free nucleoside 5 on deblocking. Acetalation of 5 gave the monoacetal 6 which was oxidized into the ketone 7. Reduction of 7 gave the allo-nucleoside 9 which on hydrolysis afforded the free nucleoside 10. Alternatively, compound 10 was obtained from mesylation of 6 to give 8 followed by subsequent acetolysis and hydrolysis.  相似文献   

6.
L. Reich  J. Don  R. R. Avtalion 《Genetica》1990,80(3):195-200
The inheritance of the red color was studied in two different varieties of tilapia which are both considered as hybrids of Oreochromis mossambicus. Crosses between red tilapia from the Philippines (PRT) and Sarotherodon galilaeus, or Oreochromis aureus gave a 1:1 ratio of red: normal and crosses between F1 black fish gave only black offspring. On the other hand crosses between the F1 red fish gave a 3:1 ratio of red:black and crosses between F1 red and black offspring gave a 1:1 ratio. These results lead to the conclusion that red color is dominant over the normal black color and controlled by a single autosomal gene (R). A unique phenotype named albino with black eyes was observed among offspring of PRT and a presumed model of inheritance of this trait is proposed. Genetic analysis of a second variety of red tilapia (derived from an unknown origin) showed the following results: crosses between parents and between their F1 offspring consistently gave 100% red fish and crosses between this red tilapia and Oreochromis aureus gave 100% black offspring. The crosses between red and black F1 of these last two crosses gave a 1:1 ratio and crosses carried out between the black F1 offspring gave a 1:3 ratio of red:black. It may be concluded from these results that the black color is dominant in this strain and that this color is controlled by a single autosomal gene (B). The presumed mode of action of the dominant gene (R) as well as of the recessive gene (b) are discussed.  相似文献   

7.
Sequential tritylation, benzoylation, and detritylation of methyl 3-deoxy-3-fluoro-β- -galactopyranoside gave crystalline methyl 2,4-di-O-benzoyl-3-deoxy-3-fluoro-β- -galactopyranoside (9), which was used as the initial nucleophile in the synthesis of the target oligosaccharide (16). Treatment of 9 with 2,3,4-tri-O-benzoyl-6-O-bromoacetyl-α- -galactopyranosyl bromide gave the corresponding disaccharide derivative 13, having a selectively removable blocking group at O-6′. Debromoacetylation of 13 afforded the disaccharide nucleophile 14 which, when treated with 2,4,6-tri-O-benzoyl-3-deoxy-3-fluoro-α- -galactopyranosyl bromide, gave the fully protected trisaccharide 15. Debenzoylation of 15 gave the title glycoside 16. Condensation reactions were performed with silver trifluoromethane-sulfonate as a promoter in the presence of sym-collidine under base-deficient conditions, and gave excellent yields of the desired β-(trans)-products. Analyses of the 1H- and 13C-n.m.r. spectra, as well as determination of the JCF and JHF coupling constants, were made by using various one- and two-dimensional n.m.r. techniques.  相似文献   

8.
Honor thy father and thy mother, say the Holy Scriptures [1], for they at least gave thee this biological life, but honor thy teachers, too, for they gave thee knowledge and example.  相似文献   

9.
Abstract

Treatment of 3′,5′-O-(tetraisopropyldisiloxanyl)adenosine and its arabino epimer with trifluoromethanesulfonyl chloride/DMAP gave the 2′-triflates in high yields. Displacements (LiN3/DMF) and deprotection gave 2′-azido-2′-deoxyadenosine and its arabino epimer which were reduced with Bu3SnH/AIBN/DMAC/benzene (or Staudinger reduction) to give 2′-amino-2′-deoxyadenosine and its epimer. Oxidation of 2′,5′-bis-O-(tert-butyldimethylsilyl)adenosine, stereoselective reduction, triflation, azide displacement, deprotection, and reduction gave 3′-amino-3′-deoxyadenosine.  相似文献   

10.
β-Galactosidase and other enzymes were immobilized on p-amino-carbanilated derivatives of cellulose and methylol cellulose using the diazo method and through glutaraldehyde. The optimum conditions for coupling cellulose tri-(p-amino-carbanilate) (CTAC) to β-galactosidase were established. The diazo coupling method with CTAC gave greater activity than with glutaraldehyde when coupled to β-galactosidase (Escherichia coli). The stability of the CTAC–β-galactosidase system was examined. The disubstituted p-amino-carbanilate derivative (CDAC) gave a lower activity, whereas the methylol analog (MCTAC) gave slightly greater activity. The CTAC was also used to immobilize glucose oxidase, trypsin, pepsin, and papain.  相似文献   

11.
Oxidation of grayanotoxin (GTX) II with lead (IV) acetate in methanol gave a new derivative, the 1(R)-spiro-3,6(S),14,16-tetra-hydroxy-5-keto derivative. Treatment of GTX-II tetraacetate in acetic acid by using Pb(IV) acetate as an oxidizing agent gave a novel 1,5-seco-GTX derivative, Δ1(10)-1,5-seco-GTX-pentaacetate, together with the 1,5-seco-GTX-1(R) derivative. Oxidation of GTX-II-tetraacetate with Tl(III) acetate in acetic acid or benzene gave the 1,5-seco-GTX-1(S) derivative.  相似文献   

12.
To make a comparison of some of the various polymerization methods, poly-γ-D -and L -glutamylglycine were synthesized through the mixed anhydride, carbodiimide, and pentachlorophenyl active ester methods. This last method proved to be best, on the basis of weight-average molecular weights (M?w). A detailed study was also carried out to determine the optimum conditions for this method. The M?w, values of the polymers were determined by the sedimentation equilibrium method; it was found that the pentachlorophenyl active ester gave M?w values of up to 11, 500 but the mixed anhydride and carbodiimide methods gave M?w, values of only about 1000. Tests with rabbit antianthrax immune serum showed that neither D - nor L -isomer precipitated with the antiserum, but that, both were able to inhibit the precipitation of the antiserum by anthrax polypeptide. In addition, the D -polymer gave more inhibition than the L , which would indicate a specificity of the antibody for D -glutamic acid residues.  相似文献   

13.
Addition of methylmagnesium iodide to methyl 2,3,6-trideoxy-3-trifluoro-acetamido-α-l-threo-hexopyranosid-4-ulose (3) gave methyl 2,3,6-trideoxy-4-C-methyl-3-trifluoroacetamido-α-l-lyxo-hexopyranoside (4) and its l-arabino analogue, depending upon the reaction temperature and the solvent. The corresponding 4-O-methyl derivatives were obtained by treatment of 4 and 5 with diazomethane in the presence of boron trifluoride etherate. Treatment of 4 with thionyl chloride, followed by an alkaline work-up, gave methyl, 2,3,4,6-tetradeoxy-4-C-methylene-3-trifluoro-acetamido-α-l-threo-hexopyranoside (8), which was stereoselectively reduced to methyl 2,3,4,6-tetradeoxy-4-C-methyl-3-trifluoroacetamido-α-l-arabino-hexopyranoside. Epoxidation of 8 with 3-chloroperoxybenzoic acid gave the corresponding 4,41-anhydro-4-C-hydroxymethyl-l-lyxo derivative (10), which was also prepared by treatment of 3 with diazomethane. Azidolysis of 10, followed by catalytic hydrogenation and N-trifluoroacetylation, gave methyl 2,3,6-trideoxy-3-trifuloroacetamido-4-C-trifluoroacetamidomethyl-α-l-lyxo-hexopyranoside.  相似文献   

14.
ORD and CD of d(+) pantothenic acid, d(+) pantothenyl alcohol and d(?) pantolactone were studied. The acid and the alcohol gave positive Cotton effects with a peak at 227 and 225 mμ, respectively, and the lactone gave a negative Cotton effect with trough at 233 mμ. They gave CD maxima at 214, 213 and 219 mµ corresponding to the inflection points of their ORD curves.

The concentrations were found to be linear to the rotation angles and the possibility of the application to quantitative analysis of the ORD was cited. The ORD showed the quantitative formation of the lactone by acid treatment of the vitamins without any racemization and hence the determination via lactone was suggested.  相似文献   

15.
Abstract

2′,3′-Dibromo-2′,3′-dideoxy-5′-O-trityl-2′,3′-secouridine (8) with sdKF gave the 3′,4′-didehydro-2,2′-anhydro nucleoside 9, which was deprotected to 10. Hydrolysis of 9 gave 3′,4′-didehydro-3′-deoxy-5′-O-trityl-2′,3′-secouridine (11a). Similarly, compound 9 with pyridinium halides gave the corresponding 2′-deoxy-2′-halo nucleosides (11b-d). Compound 11d with azide ion gave 2′-azido analogue 11e. Compound 9 with an excess amount of azide ion gave the 2′-azido triazole (13).  相似文献   

16.
A strong Cotton effect, which practically govern the sign of the optical rotation at 589 nm ([M]d), was studied in phenyl 1-thio-α (and β)-d-glycopyranosides with our new chiroptical technique. The proposal optical rotatory dispersion (ORD) method, with calculations based on a one term Drude equation, showed the presence of a strong Cotton effect at 200–210 nm. Circular dichroism (CD), with accumulation technique, also gave the same Cotton effect. Agreement in these two methods suggests the usefulness of the proposed ORD calculation method. The rotational strengths and the signs were shown to reflect the anomeric configurations and conformations (α-anomer gave positive and β-anomer gave negative signs; axial gave strong and equatorial gave weak bands). This result is an extension of the ring oxygen helicity rule of alkyl and alkyl thioglycosides to phenyl 1-thioglycopyranosides, and probably to other aromatic glycosides.  相似文献   

17.
Applications of Steinemema carpocapsae All strain in water thickener into cuts or holes made in residual rhizomes of bananas gave significant mortality of Cosmopolites sordidus larvae in the rhizomes. The methods proved suitable for field application and two large scale field trials using S. carpocapsae All and S. carpocapsae NC513 gave acceptable levels of control as measured by Vilardebo's (1973) Co-efficient of Infestation. Mortality of adult C. sordidus attracted to the application sites on treated rhizomes was observed during these field trials.  相似文献   

18.
When tributyltin oxide (TBTO) was tested by British Standard 3653 against Lyctus brunneus, 0·5 % solution, equivalent to 0·72 g/m2 surface application, gave almost complete protection. Tests to BS 3651, using larvae of Anobium punctatum transferred into fully impregnated wood gave toxic limits of 1·39–2·93 kg/m3 TBTO when benzene was used as diluent. The use of white spirit as diluent gave lower toxic limits, probably due to combined toxic action of TBTO and white spirit residues. TBTO appears to have no contact action against the insects tested. Probit analysis of the test with A. punctatum gave an LD 50 of 0·254 kg/m3 and an LD99 of 3 kg/m3. The advantage of treating results by probit analysis rather than by deriving ‘toxic limits’ is discussed.  相似文献   

19.
Zymograms of single individuals of Aedes aegypti were obtained by means of starch gel electrophoresis, using alpha-naphthyl acetate as substrate. Inbred lines gave consistently homogeneous patterns; earlier results from random-breeding laboratory strains had shown considerable variability. Six distinct bands were observed. The furthest moving band, designated Esterase 6, showed differential migration in two inbred lines. Reciprocal crosses between these lines gave F1 progeny showing both bands. Backcrosses of F1 to either parental line gave a 1:1 segregation. These results are consistent with the hypothesis that the two forms of Esterase 6 are controlled by a single pair of codominant alleles at a single gene locus (Est 6 a and Est 6 b). Linkage tests with marker genes have demonstrated that Est 6 is on linkage group 2, with the following alignment: spot-abdomen (9.0±1.0) yellow-larva (17.4±1.3) Est 6. Crosses with another inbred line demonstrated a third band with intermediate mobility, designated Est 6 c. An additional electrophoretic variant which seems to have a simple Mendelian basis was found in esterase band 1.This work was supported by NIH Research Grant No. A1-02753.  相似文献   

20.
Carpospores of Liagora farinosa from the western Mediterranean in culture gave rise to an Acrochaetium-like phase with filamentous prostrate and sparsely branched erect systems. This phase reproduced readily by tetraspores and monospores. The tetrasporangia were found to go through meiosis and the four haploid spores then gave rise to filamentous protonemal growths on which buds arose that developed into typical (though usually uncalcified) Liagora thalli. The monospores appeared to repeat the Acrochaetium-phase. These observations suggest that Liagora farinosa is another example of those members of the Nemalionales which show a heteromorphic life-history, with the sporophyte generation respresented by a dwarf phase.

Some aspects of the developmental physiology of the species are discussed.  相似文献   

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