Leurosine me­thio­dide–methanol–water (1/3/2)

The crystal structure of a methanol–water solvate ofleurosine me­thio­dide, (leurosine‐CH₃)⁺I^?·3CH₃OH·2H₂O (C₄₇H₅₉IN₄O₉·3CH₃OH·2H₂O), is described. The piperidine ring of the upper part of the mol­ecule adopts a sofa conformation. An intramolecular hydrogen bond between the tertiary N and the hydroxyl group of the vindoline moiety of the mol­ecule is present.     

Selective deoxygenation of leurosine: concise access to anhydrovinblastine

Straightforward access to anhydrovinblastine starting from the parent alkaloid leurosine is reported. The key deoxygenation step was first optimized on a model substrate. However, applied to leurosine, only the low-valent Cp2TiCl gave satisfactory results.     

Alkaloid Production in Catharanthus Roseus Cell Cultures. XI. Biotransformation of 3′, 4′-Anhydrovinblastine to Other Bisindole Alkaloids

Biotransformation studies of 3′,4′-anhydrovinblastine (1) in Calharanthus roseus cell suspension cultures are reported. A detailed study of one cell line, coded at ?916”?, has revealed that 1 is transformed to the natural bisindole alkaloids leurosine ( 2 ) and Catharine ( 3 ) in approximately 25–30 and 9–16% yield, respectively. In 24–48 h, about 40% of 1 is utilized by the cells. Conditions for biotransformation of 1 have not been optimized so the above yields quoted are not final.     

Biosynthesis of the Indole Alkaloids. Cell-free Systems from Catharanthus roseus Plants

Cell-free systems from Catharanthus roseus plants are utilized for various studies relating to the biosynthesis of indole alkaloids. Tryptamine ( 5 ) and secologanin ( 6 ), two fundamental building units, are shown to be incorporated into the alkaloid vindoline ( 7 ). In another study, catharanthine ( 18 ) and vindoline ( 7 ) are utilized by this enzyme system and coupled to the important bisindole biointermediate 3′,4′-anhydrovinblastine

1 The previously [20] used name for 17 , 3′, 4′-dehydrovinblastine, is incorrect.

( 17 ). The latter substance is, in turn, incorporated and converted to the natural alkaloids leurosine ( 8 ), Catharine ( 9 ) and vinblastine ( 10 ), thereby providing information about the biosynthesis of these complex molecules. High pressure liquid chromatography assay of the enzymic mixture sheds light on the enzymes involved in the coupling of 18 and 7 .     

Concise synthesis of anhydrovinblastine from leurosine

[reaction: see text] The Cp(2)TiCl-mediated deoxygenation of leurosine (1) afforded anhydrovinblastine (4) in good yield. Furthermore, as the reaction proceeded via a carbon-centered radical intermediate, this transient was also trapped by a hydrogen-atom donor to afford selectively reduced alkaloid 10.     

Macrocyclische Spermidinalkaloide aus Pleurostylia africana LOES. 9. Mitteilung über Celastraceen-Inhaltsstoffe

Macrocyclic Spermidine Alcaloids from Pleurostylia africana LOES . The structure of pleurostyline, a new macrocyclic spermidine alkaloid from Pleurostylia africana (Celastraceae), has been elucidated mainly by ¹H- and ¹³C-NMR.-spectroscopy. Pleurostyline represents a new structure type in which spermidine is incorporated in a 13-membered lactam ring to which an additional cinnamoyl residue is fused to yield a 7-membered ring. The same plant contains also the spermidine alkaloids celacinnine and cellallocinnine of which ¹³C- and high field ¹H-NMR.-measurements have been carried out for the first time. Both alkaloids are interconvertible by UV.-irradiation. In addition the existence of rotational isomerism of one amide group of these alkaloids has been demonstrated by NMR.-spectroscopy.     

The structure of α-(1,2-dithiole-3-ylidene) ketones and α-(1,2-dithiole-3-ylidene) aldehydes studied by means of n.m.r. spectroscopy

1H and ¹³C n.m.r. studies of a series of twelve 1,2-dithiole-3-ylidene ketones and aldehydes have shown that the geometry of the carbon backbone is the same as found in 1,6,6aλ⁴-trithiapentalenes. No evidence has been found which favours a bicyclic structure for the system. A linear correlation of observed ¹³C chemical shifts with calculated charge densities is found to be valid. The observations are in agreement with a structure which is a hybrid between a true ketonic structure and a true mesoionic structure. By using the difference in the ¹³C chemical shifts of ortho and meta carbon atoms in substituent phenyl groups it is possible to qualify the degree of coplanarity of the phenyl groups with the backbone of the molecule.     

N.m.r. studies in the heterocyclic series: XVI—determination of the structure of 3-azidoindazole by 1H and 13C n.m.r. spectroscopy

The 1-NH structure for 3-azidoindazole has been demonstrated by the observation of ¹H? ¹H and ¹³C? ¹H couplings involving the hydrogen atom attached to nitrogen. A comparison between 3-azidoindazole and indazole shows that both compounds have the same tautomeric structure.     

Polysulfonylamines. CXXXII.

The crystal structure of the title compound, C₅H₇N₂⁺·C₁₂H₁₀NO₄S₂⁻, consists of two independent cation–anion pairs, A and B. Within each pair, the H—N—C—N*—H grouping (N*—H is the pyridinium function) and one N—S—O moiety of the anion are linked by N*—H⃛N and N—H⃛O hydrogen bonds to form an antidromic ring motif of type R²₂(8). The remaining amino donors give rise to N—H⃛O hydrogen bonds, connecting the ion pairs into A–B–A–B– chains. The structure testifies to the persistence of the R²₂(8) motif in question, which was previously detected as a highly robust supramolecular synthon in a series of onium di(methane­sulfonyl)­amidates. The structure is pseudosymmetric; the anion positions correspond to space group P2₁/n, but those of the cations do not.     

Synthesen in der Isocamphanreihe, 37. Mitt.: Analytik und Geruch isomerer cyclischer Acetale mit Norbornanstruktur

Summary The separation of a complex mixture of a fragrance material into its isomers is described. Instead of an odour of sandalwood the mixture exhibits mainly a mushroom odour but also the pure isomers show other organoleptic qualities. The structure of two isomers could be ascertained mainly by¹³C- and¹H-NMR-measurements, for two isomers a structure proposal is given.

Herrn Prof. Dr. Wilhelm Fleischhacker mit den besten Wünschen zum 60. Geburtstag gewidmet     

Neue Verbindungen mit Granatstruktur. VI. Vanadate

New Compounds with Garnet Structure. VI. Vanadates The preparation of vanadate-garnets of the following three types is reported: (I) {Na₃}[B₂^III](V₃)O₁₂ (B^III = Cr, Sc), (II) {LiCa₂}[B₂^II](V₃)O₁₂ (B^II = Mg), (III) {Ca₂A^III}[Li₂] (V₃)O₁₂ (A^III = In, Sc). The Cr-compound of type (I) decomposes above 690°C into a mixture of Cr₂O₃ and NaVO₃. The analogous Fe-compound decomposes in a similar way already at 400°C; therefore the preparation by solid state reaction is not possible. Employing larger B^III-ions (Y, Yb, Lu) no garnets of type (I), but mixtures of B^IIIVO₄ (zircon structure) and Na₃B^IIIV₂O₈ are formed. Garnets of type (II) do not exist, when B^II are Co and Ni. Mixtures of {Ca₃}[LiB^II](V₃)O₁₂ (garnet structure), LiB^IIVO₄ (spinel structure) and B₃^II(VO₄)₂ are formed. With type (III) for A^III = Y reaction occurs forming a mixture of YVO₄, Ca₃(VO₄)₂ and Li₃VO₄.     

Anti‐inflammatory drugs. IX.

In the solid‐state structure of the title compound, C₄H₁₂N⁺·C₁₄H₁₀Cl₂NO₂^?·H₂O, the asymmetric unit contains one cation, one anion and a water mol­ecule. A complex network of hydrogen bonds is present. A comparison is made with the structure of the an­hydro­us salt.     

Determination of the structure factor for concentrated silica dispersions using small angle x-ray scattering. II. Experiment

The structure factor of a number of silica suspensions in cyclohexane, with concentrations ranging from 0.01 to 0.714 gcm^–3, has been determined with small angle x-ray scattering, using a Kratky camera. The experimental structure factor is compared with a theoretical one for which polydispersity effects on the particle scattering factor and on the structure are explicitly taken into account.Analysis of the scattered intensity at a scattering angle=0 shows that the particles in the suspension interact like hard spheres, with a specific hard sphere volume of 0.61 cm³g^–1. A comparison of the experimentally determined structure factor with the structure factor found by a model calculation for a polydisperse system, using the experimental particle size distribution, showed a general agreement. The height of the first maximum agreed well for all concentrations, however its position varied stronger with concentration in the experimental curves. A possible explanation of this effect is given.     

The case for a revised structure for hypophyllanthin - an analysis of the 13C N.M.R. spectra of aryltetralins

A revised structure for hypophyllanthin is proposed on the basis of its ¹³C n.m.r. spectrum. ¹³C n.m.r. spectra also support the previously proposed structure for nirtetralin and assist in the structural elucidation of a new aryltetralin lignan.     

Structure investigations by P.A.C.

The perturbed angular correlation /P.A.C./ technique is employed to investigate the structures of barium ferrite and barium hexaferrite using radioactive¹³³Ba /10.7 Y/ as a probe. The quadrupole interaction frequencies /W_Q'S/ are found to be 9.68 and 12.02 Mrad sec^–1 for barium ferrite and barium hexaferrite, respectively, showing a drift from usual cubic structure.     

Study of alkaloids from the flora of the Siberian and Altai regions. 6. Crystal and molecular structure of songorine Z-oxime

Oximation of songorine afforded a mixture of its Z- and E-oximes. The crystal and molecular structure of the Z-isomer was established by X-ray diffraction analysis. Its structure was also confirmed by the spectral data (2D ¹H—¹H and ¹³C—¹H NMR spectroscopy and mass spectrometry). The structure of isomeric E-oxime was established by comparing its NMR spectroscopic data (¹H and ¹³C) with the data for the Z-isomer.     

Defects in polydiacetylene single crystals. II. Dislocations in pTS

The structure of single crystals of a substituted diacetylene polymer (pTS) has been investigated by using transmission electron microscopy. It has been found that edge dislocations with Burgers vector parallel to the chain direction are present at a density of up to 10¹³ m^?2. It is suggested that the dislocations may be present first of all in the monomer crystals and become locked into the monomer structure during polymerization. It has been found that the dislocations have a tendency to line up in rows perpendicular to the chain direction and when the density of the dislocations in a row is sufficiently high a small?angle grain boundary can be formed. A possible structure for the dislocations on a molecular level is suggested and the effect of the presence of the dislocations upon the polymerization behavior, mechanical properties, and electric properties is discussed.     

Über Chalkogenolate. 102. Untersuchungen über Halbester der Monothiokohlensäure. 2. Kristallstruktur von Rubidiummethyloxoxanthat

On Chalcogenolates. 102. Studies on Hemiesters of Monothiocarbonic Acid. 2. Crystal Structure of Rubidium Methyl Oxoxanthate Rb[SOC? OCH₃] crystallizes with Z = 4 in the monoclinic space group P2₁/c with cell dimensions a = 4.332(3) Å, b = 11.349(5) Å, c = 10.673(5) Å, β = 92.9(5)°. The structure has been determined from single crystal X-ray data by means of Patterson and Fourier syntheses and refined to a final conventional R value of 0.045 using 983 independent reflexions. The structure consists of Rb⁺ and [SOC? OCH₃]^? ions. The rubidium ion is bonded to five oxygen and three sulfur atoms. The coordination polyhedron is a bicapped trigonal prism.     

Aripiprazole salts. I. Aripiprazole nitrate

The crystal structure of aripiprazole nitrate (systematic name: 4‐(2,3‐dichlorophenyl)‐1‐{4‐[(2‐oxo‐1,2,3,4‐tetrahydroquinolin‐7‐yl)oxy]butyl}piperazin‐1‐ium nitrate), C₂₃H₂₈Cl₂N₃O₂⁺·NO₃⁻ or AripH⁺·NO₃⁻, is presented and the molecule compared with the aripiprazole molecules reported so far in the literature. Bond distances and angles appear very similar, except for a slight lengthening of the C—NH distances involving the protonated N atom, and the main differences are to be found in the molecular spatial arrangement (revealed by the sequence of torsion angles) and the intermolecular interactions (resulting from structural elements specific to this structure, viz. the nitrate counter‐ions on one hand and the extra protons on the other hand as hydrogen‐bond acceptors and donors, respectively). The result is the formation of [100] strips, laterally linked by weak π–π and C—Cl...π interactions, leading to a family of undulating sheets parallel to (010).     

Sulphur-Nitrogen Chelating Agents. IV. Some Solid State Copper(II) Complexes of Thia-aminopyridines An I.R. and Reflectance Spectral Analysis

A series of solid state Cu^II complexes with thia-aminopyridines . S(CH₂)_mNH₂ have been prepared and characterized. The postulated structures of these CuLX₂ (X = OAc^?, NO₃^?, ClO₄^? or Cl^?) compounds were based on their I.R. and electronic spectra. It was found that the thiaaminopyridines may coordinate in quite different ways. In contrast with what was found for the aliphatic thiadiamines, no relation was stated between the structure of the CuLX₂ compounds and the nature of the X^? anion. Moreover the solid state compounds do not give a clear indication for the structure of the CuL²⁺ species in aqueous solution.