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1.
Summary The recently developed relativistic double perturbation theory is extended to handle relativistic changes of molecular structure more easily. This is achieved by simple coordinate scalings. Accurate higher order mixed perturbation energies for H 2 + are calculated. The relativistic changes of bond energy,DE, of bond length,R e , and especially of force constant,k, and of anharmonicity,a, are large, up to 100%·(Z/c)2. The dominant contributions tok anda are due to the indirect change of the nonrelativistick anda connected with the relativistic change of bond length. Accordingly the relativistic changes obey Badger's and Gordy's rules (–RDEk).Dedicated to Prof. Klaus Ruedenberg in appreciation of his fundamental contributions to both formal theory and physical explanations in quantum chemistry  相似文献   

2.
Summary The identification of small amounts of sugars by their X-ray powder diagrams is suggested as a most simple and practical method in routine analysis.It is especially valuable in working with minute amounts of material, and has proved very useful for the final identification of chromatographically-separated sugars.The characteristics of the powder diagrams of a number of monosaccharides of special interest to the physiological chemist are reported in detail. The substances thus investigated are- and-D-glucose and-glucose monohydrate,- and-D-galactose,- and-D-mannose,D-fructose,D-glucuronolactone,- and-D-glucosamine hydrochloride,- and-D-galactosamine (chondrosamine) hydrochloride,-L-fucose, andD-ribose. For various reasons arabinose, lyxose, and xylose have also been included.It is clear from the powder diagrams of the galactoses that the crystalstructure earlier ascribed to-galactose is that of-galactose.A single-crystal study of-glucosamine hydrochloride was carried out by theWeissenberg technique. The crystal-dimensions obtained agree with those earlier found byCox et al5, 7.The optical rotation of chondrosamine hydrochloride was found to be [] D 20° = - 135° - 93° - 39°, the first value being considerably higher than that given for the-form byLevene. A method for the preparation of-mannose is described.
Zusammenfassung Die Identifizierung kleiner Mengen verschiedener Zuckerarten mit Hilfe ihrer Röntgen-Pulverdiagramme wird als einfache und praktische Routinemethode vorgeschlagen.Diese Methode ist besonders wertvoll, wenn nur kleine Substanzmengen zur Verfügung stehen, und hat sich für die endgültige Identifizierung von chromatographisch getrennten Zuckern als sehr geeignet erwiesen.Die Einzelheiten der Pulverdiagramme folgender physiologisch-chemisch bedeutungsvoller Monosaccharide werden mitgeteilt:- und-D-Glukose und Glukosehydrat,- und-D-Galaktose,- und-D-Mannose,D-Fruktose,D-Glukuronolakton,- und-D-Glukosaminhydrochlorid,- und-D-Galaktosamin-(Chondrosamin)-hydrochlorid,-L-Fukose, dieD-Pentosen Arabinose, Lyxose, Ribose und Xylose.Aus den Pulverdiagrammen der Galaktosen geht deutlich hervor, daß die Krystallstruktur, die früher der-Galaktose zugeschrieben wurde, tatsächlich diejenige der-Form ist.Die Untersuchung eines Einzelkristalles von-Glukosaminhydrochlorid wurde nach derWeissenberg-Technik ausgeführt. Die erhaltenen Werte stimmen mit den früher vonCox und Mitarbeitern gefundenen überein.Die optische Drehung des Chondrosaminhydrochlorids wurde zu [] D 20° = + 135° + 93° + 39° gefunden. Der erstgenannte Wert ist größer als der entsprechende, vonLevene angegebene Drehungswert.Eine Methode zur Darstellung von-Mannose wird beschrieben.

Résumé On propose une méthode de routine simple et pratique pour l'identification de petites quantités de divers sucres au moyen de leur diagramme de poudres aux rayons X. Cette méthode est particulièrement précieuse quand on n'a que de petites quantités de matière à sa disposition et elle s'est montrée très convenable pour l'identification finale de sucres séparés par chromatographie. Des particularités des diagrammes de poudres des monosaccharides suivants intéressent le chimiste physiologiste: et-D-glucose et hydrate de glucose, et-D-galactose, et-D-mannose, D-fructose,D-glucuronolactone, chlorhydrate d' et-D-glucosamine, chlorhydrate d' et-D-galactosamine (chondrosamine), l'-L-fucose, lesD-pentoses, l'arabinose, le lyxose, le ribose, le xylose. Des diagrammes de poudres des galactoses découle clairement le fait que la structure cristalline qui fut attribuée précédemment à l'-galactose est celle de la forme. L'expérience sur un cristal unique de chlorhydrate d'-glucosamine a été effectuée d'après la technique deWeissenberg. Les valeurs obtenues concordent avec celles trouvées précédemment parCox et ses collaborateurs. Le pouvoir rotatoire du chlorhydrate de chondrosamine a été trouvé égal à D 20 = + 135° + 93° + 39°. La première valeur est plus grande que celle donnée parLevene. On décrit une préparation de l'-mannose.


With 3 figures.  相似文献   

3.
In neutral and alkaline solutions, tetrakis(4-carboxyphenyl)porphyrin (TCPP) and tetrakis(4-sulfonatophenyl)porphyrin (TSPP) form 1:1 and 2:1 host–guest inclusion complexes with -cyclodextrin (-CD), -cyclodextrin (-CD), and 6-deoxy-6-diethylamino--CD (DEA--CD), except for DEA--CD in alkaline solution. On the other hand, TCPP and TSPP form only 1:1 inclusion complexes with 6-deoxy-6-dihexylamino--CD (DHA--CD). The limited solubilities of DEA--CD in alkaline solution and DHA--CD are likely responsible for no observation of the 2:1 inclusion complex containing DEA--CD in alkaline solution and that containing DHA--CD. The equilibrium constants (Ks) of TCPP and TSPP for the formation of the inclusion complexes have been estimated from the absorption and/or fluorescence intensity changes in neutral and alkaline solutions. The K2 values, which are the equilibrium constants for the formation of the 2:1 host–guest inclusion complex from the 1:1 inclusion complex, are about one tenth the corresponding K1 values, except for the -CD–TSPP system in alkaline solution. In neutral solution, where DEA--CD and DHA--CD are in protonated forms, the electrostatic force operates between DEA--CD (DHA--CD) and TCPP (TSPP), leading to the greater K values than those in alkaline solution, where DEA--CD and DHA--CD exist as neutral species.  相似文献   

4.
Glaser  Robert  Geresh  Shimona  Luria  Shlomo  Drouin  Marc  Michel  André 《Structural chemistry》1994,5(4):277-282
Hydrogenation ofZ-(–)-(1R, 3R, 4S)-menthyl 2-formamido-4,4,4-trifluoro-2-butenoate catalyzed by Pd/C was performed at atmospheric pressure to yield a mixture of (2R, 1R, 3R, 4S)- and (2S, 1R, 3R, 4S)-menthyl 2-formamido-4,4,4-trifluorobutanoate diastereomers in a 5545 ratio, respectively. Repeated fractional crystallization from ethyl acetate and vapor diffusion of petroleum ether afforded (+)–(2S, 1R, 3R, 4S)-menthyl 2-formamido-4,4,4-trifluorobutanoate as clear colorless, crystalline prisms which were subjected to single-crystal X-ray diffraction analysis. The crystals belong to the orthorhombic system P212121, and at 213 K:a=5.054(1),b= 10.000(2),c=32.707(1) Å,V=1652.9(4) Å3,Z=4,R(F)=0.040, andR w (F)=0.037. The finding of the (2S)-configuration for the formamido-acid portion of the (+)-ester enabled the configurational assignment of the asymmetric hydrogenation products ofZ-methyl 2-formamido-4, 4,4-trifluoro-2-butenoate catalyzed by chiral diphosphine/rhodium(I) complexes.  相似文献   

5.
TheSomogyi-Nelson colorimetric method is applied in a new manner more suitable for evaluating the kinetics of the enzyme hydrolysis of sodium carboxymethylcellulose (Na-CMC) catalyzed by the cellulase complex. By means of selective inhibition of a chosen enzyme from the cellulase complex it became possible to trace the effect of the other enzymes included in its composition.
Kinetik und Mechanismus der Hydrolyse von Natriumcarboxymethylcellulose (Na-CMC) durch einen Cellulase-Komplex
Zusammenfassung Die kolorimetrische Methode nachSomogyi undNelson wird nach einem neuen Verfahren zur Verfolgung der Kinetik der hydrolytischen Spaltung von Natriumcarboxymethylcellulose (Na-CMC), katalysiert durch den Cellulase-Komplex, angewandt. Durch selektive Inhibierung eines bestimmten Enzyms des Cellulase-Komplexes kann man die Wirkung der anderen zu seiner gesamten Zusammensetzung gehörenden Enzyme verfolgen.

Symbols Used E enzyme (E—cellulase;E—exo-cellobiohydrolase;E—-glucosidase) - [E] w weight concentration of enzymeE - S substrate (Na-CMC—sodium carboxymethylcellulose) - [S]0 weight concentration of substrateS - I inhibitor (I—lactose;I—calcium chloride;I—condurrite-B-epoxide) - P product (P—oligosaccharides;P—cellobiose;P—D-glucose) - P end product (K , K , K ) - DP degree of polymerization - DS degree of substitution - ES enzyme-substrate complex (E S, E S, E S) - EP enzyme-product complex (E P, E P) - EI enzyme-inhibitor complex (E I, E I, E I) - M s molecular mass of substrateS - K s substrate constant (K s , K s , K s ) - K I inhibitor constant (K I , K I , K I ) - K m Michaelis-Menten constant - k +1,k +2 (k +2 ,k +2 ,k +2 ) forward rate constants - k –1 reverse rate constant - 0 initial rate of reaction - V maximal reaction rate - A change in absorbance - molar absorption coefficient - wavelength Herrn Prof. Dr.Hans Tuppy zum 60. Geburtstag herzlichst gewidmet.  相似文献   

6.
A study is made of the reaction of the sodium and ammonium salts of 1 -alkyl- and 1, 2-dialkyl-4-nitro-5 mercaptoimidazoles with -halogenoketones, -halogenoalcohols, and — and -halogeno acids, to give a number of 1 -alkyl- and 1, 2-dialkyl-4-nitro-5- [-ketoalkyl (aralkyl)-, -hydroxyethyl-, and -and -carboxyalkyl] mercaptoimidazoles.For Part XXIV see [6].  相似文献   

7.
8.
Enthalpies of protonation of polyacrylates and polymethacrylates with different molecular weights in aqueous NaCl solutions, 0 I 2 mol-L–1 were determined by titration calorimetry at 25°C. H values are dependent on both the neutralization degree, , and the molecular weight of polyacids. T S of protonation was obtained using pK values already reported and the present H results. Empirical equations for the dependence on I, , and molecular weight are reported for both H and T S.  相似文献   

9.
Summary The virial theorem for a molecule in the relativistic clamped-nuclei approximation is derived. The individual energy contributionsA (momentum energy),B (mass energy),T=A+B (kinetic energy) andV (potential energy) are expressed in terms ofE, E/R (derivate w.r.t. the nuclear coordinates) and the relativistic correction E/2 (derivative w.r.t. Sommerfield's fine-structure constant ). IfE and E/R are known as functions of , then all individual energy terms are also known as functions of . As an example, numerical results for H 2 + are presented. The relativistic and nonrelativistic potential energy curves and the paradoxical behavior of their different contributions are analyzed and interpreted in both the largeR and shortR ranges.Dedicated to Professor W. Kutzelnigg on the occasion of his 60th birthday  相似文献   

10.
Conclusions When heated in the presence of a catalytic amount of BF3 etherate,-trifluoromethyl--diethylamino--fluoroacrylic acid N, N-dimethylamide is reversibly isomerized to-trifluoromethyl--dimethylamino--fluoroacrylic acid N, N-diethylamide. The methyl esters of-trifluoromethyl--diethylammo--fluoroacrylic acid and-trifluoromethyl--phenoxy--fluoroacrylic acid N,N-dimethylamide are not isomerized under the same conditions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No.1, pp.137–141, January, 1976.  相似文献   

11.
The contact angle,, formed by a liquid on a solid surface in air depends on the solid-air ( S ), liquid-air ( L ) and solid-liquid ( SL ) interfacial free energies, as described by Young's equation. Critical examination of reported contact angles for numerous liquids and solids leads to an empirical correlation between sL and both Y and S . Combination of this correlation with Young's equation gives an empirical relation allowing calculation of S from L and Calculations made with these empirical relations agree well with estimations of S obtained by the method of critical spreading, and are consistent with Young's equation.Founded and supported by F. Hoffmann-La Roche and Co., Limited Company, Basel, Switzerland.  相似文献   

12.
In many textbooks attention is drawn to the close analogy that seems to exist between the Electron-in-a-Box-wave functions n and their LCAO-MO counterparts J (J = n) for the movement of an electron in a -system. It is often implied that the wave lengths of n and of J (J = n) which satisfy to a high degree the relation =, have the same physical meaning. It is shown that this is not the case. for a linear system (e.g. a one-dimensional Electron-in-a-Box-model) is directly connected with the momentum of the electron and therefore with its kinetic energy according to the deBroglie relation. However, there is no such simple relationship between A and the corresponding kinetic energy component in LCAO-MO's J . (The necessary two-center kinetic energy integrals have been computed for 1s-type atomic orbitals.)
Zusammenfassung In vielen elementaren Textbüchern wird die Aufmerksamkeit auf die scheinbar enge Verwandtschaft hingelenkt, die zwischen den Wellenfunktionen n für ein Electron-in-a-Box-Modell und den entsprechenden LCAO-MOs J (J=n) für die Bewegung eines Elektrons in einem -System besteht. Unter anderem wird oft implizit angenommen, daß die Wellenlängen der Funktion n und von J (J=n), die weitgehend der Bedingung = genügen, die gleiche physikalische Bedeutung haben. In dieser Arbeit wird gezeigt, daß dies nicht der Fall ist. Für ein lineares System (z. B. ein eindimensionales Electron-in-a-Box-Modell) ist über die deBroglie'sche Beziehung direkt mit dem Impuls und damit mit der kinetischen Energie des Elektrons verknüpft. Im Gegensatz dazu existiert keine einfache Beziehung zwischen und der entsprechenden Komponenten der kinetischen Energie in einem LCAO-MO J . (Die notwendigen Zweizentrenintegrale der kinetischen Energie wurden für Atomorbitale vom 1s-Typus berechnet.)

Résumé Dans les textes élémentaires de chimie théorique on attire souvent l'attention sur l'analogie qui semble exister entre les fonctions d'onde n pour un modèle «Electron-in-a-Box» et les fonctions correspondantes LCAO-MO J (J=n) décrivant le mouvement d'un électron dans un système . En particulier cette comparaison implique que les «longueurs d'onde» de n et de J (J=n), qui satisfont pratiquement la relation =, ont la même signification physique. Dans ce travail on montre, que ceci n'est pas le cas. Pour un système linéaire (c.à.d. un modèle linéaire du type «Electron-in-a-Box») est reliée directement à la quantité de mouvement et par là à l'énergie cinétique, par la relation de deBroglie. Par contre on ne trouve pas une dépendance analogue entre et la composante correspondante de l'énergie cinétique dans une orbitale moléculaire LCAO J. (Les intégrales bicentriques pour les composantes d'énergie cinétique nécessaires à ce calcul ont été déterminées pour des orbitales atomiques du type 1s.)
  相似文献   

13.
The structure-property relationships derived here permit the prediction of both the zero-shear viscosity 0, as well as the shear rate dependent viscosity . Using this molecular modeling it is now possible to predict over the whole concentration range, independently of the molecular weight, polymer concentration and imposed shear rate. However, the widely accepted concept: dilute — concentrated, is insufficient. Moreover it is necessary to take five distinct states of solution into account if the viscous behavior of polymeric liquids is to be described satisfactorily. For non-homogeneous, semi-dilute (moderately concentrated) solutions the slope in the linear region of the flow curve (= must be standardized against the overlap parameterc · []. As with the 0-M-c-relationship, a-M -c- relationship can now be formulated for the complete range of concentration and molecular weight. Furthermore, it is possible to predict the onset of shear induced degradation of polymeric liquids subjected to a laminar velocity field on the basis of molecular modeling. These theoretically obtained results lead to the previously made ad hoc conclusion (Kulicke, Porter [32]) that, experimentally, it is not possible to detect the second Newtonian region.Roman and Italian symbols a exponent of the Mark-Houwink relationship - b exponent of the third term of the 0-M -c relationship - c concentration /g · cm–3 - E number of entanglements per molecule - F(r) connector tension - f function - G i A shear modulus; A indicates that it /Pa has been evaluated by a transient shear flow experiment; i is the shear rate to whichG A refers to - G storage modulus /Pa - G p plateau modulus /Pa - H() relaxation spectrum /Pa - h shift factor (0/r) - K H Huggins constant - K b third constant of the 0-M -c relationship - K constant of the Mark-Houwink relationship - M molecular weight /g · mol–1 - M e molecular weight between two /g · mol–1 entanglement couplings - N number of segments per molecule - n slope in the power-law region of the flow curve - p p-th mode of the relaxation time spectrum - R gas constant /8.314 J·K–1·mol–1 - r direction vector - T temperature /K Greek symbols ß reduced shear rate - shear rate /s–1 - shear viscosity /Pa·s - s solvent viscosity /Pa·s - sp specific viscosity - 0 zero-shear viscosity /Pa·s - apparent viscosity at shear rate - reduced viscosity - viscosity of polymeric liquid in /Pa·s the second Newtonian region - [] intrinsic viscosity/cm3·g–1 - screening length/m - /g·cm –3 density - relaxation time/s - 0 experimentally derived relaxation time/s - angular frequency of oscillation Indices conc concentrated - corr slope corrected - cr critical - deg degradation - e entanglement - exp experimental - mod moderately concentrated/semi-dilute - n number average - p polymer - R Rouse - rep reptation - s solvent - sp specific - theo theoretical - weight average - relaxation time - o experimental or steady state - * critical - ** transition moderately conc. — conc. - + transition dilute — moderately cone. Paper presented at the 2nd bilateral U.S.-West German Polymer Symposium, Yountville, the 7th–11th September 1987.  相似文献   

14.
Summary The synthesis of the heptacosapeptide amide with the primary structure of Human-secretin is described. For this purpose 7 fragments were designed, i.e. H-Gly-Leu-Val-NH2 25–27b,Z-Arg(Z 2)-Leu-Leu-Gln-OH 21–24,Z-Arg(Z 2)-Leu-Gln-OH 18–20,Z-Arg(Z 2)-Glu(OtBu)-Gly-Ala-OH 14–17,Z-Arg(Z 2)-Leu-OH 12–13,Z-Thr(tBu)-Ser(tBu)-Glu(OtBu)-Leu-Ser(tBu)-OH 7–11,Adoc-His(Adoc)-Ser(tBu)-Asp(OtBu)-Gly-Thr(tBu)-Phe-OH 1–6 these fragments were consequently assembled to the overall protected total sequence using the Wünsch/Weygand-method with dicyclohexylcarbodiimide. After deprotection by exposure to trifluoroacetic acid in presence of 1,2-ethanedithiol and water as scavenger, the isolated crude product was purified by column chromatography on CM-Sepharose, fast flow. This synthetized Human-secretin showed the full biological activity in comparison to Porcine-secretin.
Herrn Prof. Dr. E. Bayer zum 65. Geburtstag gewidmet.  相似文献   

15.
Previously unknown symmetrical and unsymmetrical , '-dialkoxytetracarbocyanine and , '-dialkoxypentacarbocyanine dyes have been synthesized by the condensation of -alkoxy-substituted hexamethine and octamethine hemicyanines with quaternary salts of -alkoxypropenyl derivatives of heterocyclic bases. Tetracarbocyanines with a symmetrical structure have also been obtained by the direct interaction of quaternary salts of -alkoxypropenyl derivatives of heterocyclic bases with malonaldehyde dianil.  相似文献   

16.
The vertical valence ionization potentials of cyclopropane, ethylene oxide and ethylene imine are calculated by a many-body Green's function method. For C3H6 the ordering of the ionization potentials is 2e(), 1e(), 2a1(), 1a2(), 1e(). The assignment of the 2a1 and the 1a2 ionization potentials which has been controversial is thus clarified. The ordering is in agreement with the result obtained via Koopmans' theorem. For ethylene oxide and ethylene imine Koopmans' theorem fails in predicting the correct order of ionic states. For C2H4O the ordering of the ionization potentials is 2b 1(), 4a 1, 1a 2(), 2b 2,3a 1, 1b 1(), 1b 2, 2a 1 and for C2H5N 6a, 5a, 3a, 2a, 4a, 3a, 1a, 2a. The agreement of the computed ionization potentials with the experimental values is very satisfactory.  相似文献   

17.
Unicyclic Graphs with Minimal Energy   总被引:7,自引:0,他引:7  
If G is a graph and 1,2,..., n are its eigenvalues, then the energy of G is defined as E(G)=|1|+|2|++| n |. Let S n 3 be the graph obtained from the star graph with n vertices by adding an edge. In this paper we prove that S n 3 is the unique minimal energy graph among all unicyclic graphs with n vertices (n6).  相似文献   

18.
A variational method is proposed which results in an approximate wave function for an excited state which has the maximum overlap with the true excited state eigenfunction. The method involves the calculation of the quantities E=¦H¦ and =¦(H-E)2¦, but is free of the constraint that the trial function must remain orthogonal to all states of the same symmetry which lie beneath it. One must know, however, an approximation to the true eigenvalue. A discussion is given on how one might gain the latter information, lacking knowledge of the spectrum, from the repeated application of the method.
Zusammenfassung Es wird eine Variationsmethode vorgeschlagen, die auf eins genäherte Wellenfunktion für einen angeregten Zustand führt, welche sich maximal mit der wahren Eigenfunktion des angeregten Zustandes überlappt. Die Methode ermöglicht die Berechnung der Größen: E=¦H¦ und =¦(H-E)2¦, ist aber frei von der Nebenbedingung, daß die Versuchsfunktion orthogonal zu allen benachbarten Zuständen mit derselben Symmetrie bleiben muß. — Man will jedoch eine Näherung des wahren Eigenwertes wissen. — Eine Diskussion darüber, wie man durch wiederholte Anwendung der Methode letztere Information gewinnen kann, ohne Kenntnisse über das Spektrum zu besitzen, wird durchgeführt.

Résumé Méthode variationnelle pour la détermination d'une fonction d'onde d'un état excité présentant le recouvrement maximum avec la fonction d'onde exacte. La méthode implique le calcul de E=¦H¦ et =¦(H-E)2¦ mais ne comporte pas la contrainte d'orthogonalité de la fonction d'essai à tous les états inférieurs de même symétrie. On doit cependant connaître une valeur approchée de la valeur propre exacte. Discussion sur la manière dont on peut obtenir cette valeur approchée sans connaître le spectre, par application répétée de la méthode.
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19.
Seeds ofFatsia japonica(Araliaceae) afforded the known hederagenin 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranoside and the new triterpene glycoside D 2 , for which the structure hederagenin 3-O--D- galactopyranosyl-(12)-O--L-arabinopyranoside was proposed based on chemical methods and NMR spectroscopy  相似文献   

20.
Zusammenfassung Dihydro-4,4,6-trimethyl-2(1H)-pyrimidinone reagieren mit Formaldehyd und sekundären bzw. primären Aminen zu 6-Dialkylaminoäthylidentetrahydro-2(1H)-pyrimidinonen bzw. Hexahydro-2(1H)-pyrido[4,3-d]Pyrimidinonen. Mit Succindialdehyd bzw. Glutardialdehyd und primären Aminen entstehen 5,7-Äthanohexahydro-2(1H)-pyrido[4,3-d]pyrimidinone bzw. Tetrahydro-6,8-propano-6H-pyrimido[1,6-c]pyrimidin-1(2H)-one. Die 6-Dialkylaminoäthylidentetrahydro-2(1H)-pyrimidinone geben mit Phenolen Tetrahydrospiro([1]benzopyran-2,4(1H)-pyrimidin)-2(3H)-one, mit cycl. -Dicarbonylverbindungen Hexahydrospiro([1]benzopyran-2,4(1H)-pyrimidin)-2,5(3H, 6H)-dione bzw. Tetrahydrospiro(2H,5H-pyrano[3,2-c][1]benzopyran-2,4(1H)-pyrimidin)-2(3H),5-dione bzw. mit Malonestern -(Tetrahydro-4,4-dimethyl-2-oxo-6-pyrimidyl)-äthylmalonester.Zusammenfassung Dihydro-4.4.6-trimethyl-2(1H)-pyrimidinones react with formaldehyde and sec. and prim. amines resp. to 6-dialkylaminoethylidentetrahydro-2(1H)-pyrimidinones and hexahydro-2(1H)-pyrido[4.3-d]pyrimidinones, resp. succindialdehyde and glutaraldehyde with primary amines give 5.7-ethanohexahydro-2(1H)-pyrido[4.3-d]pyrimidinones and tetrahydro6.8-propano-6H-pyrimido[1.6-c]pyrimidin-1(2H)-ones, resp. 6-Dialkylaminoethylidentetrahydro-2(1H)-pyrimidinones react with phenols to tetrahydrospiro([1]benzopyran-2.4(1H)-pyrimidin)-2(3H)-ones, with cyclic -dicarbonyl compounds to hexahydrospiro([1]benzopyran-2.4 (1H)-pyrimidin)-2,5 (3H), 6H)-diones and tetrahydrospiro(2H,5H-pyrano[3.2-c][1]benzopyran-2.4(1H)-pyrimidin)-2(3H),5-diones, resp., with malonates -(tetrahydro-4.4-dimethyl-2-oxopyrimidyl-6)-ethylmalonates.
Mannich reaction with dihydro-6-methyl-2(1H)-pyrimidinones

Herrn Prof. Dr.F. Kuffner zum 65. Geburtstag gewidmet.  相似文献   

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