Megastachine, a new alkaloid from Lycopodiummegastachyum

1979 ◽  
Vol 57 (13) ◽  
pp. 1691-1693 ◽  
Author(s):  
Jean-Claude Braekman ◽  
Claude Hootele ◽  
Noah Miller ◽  
Jean-Paul Declercq ◽  
Gabriel Germain ◽  
...  
Keyword(s):  
Diffraction Analysis ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lycopodium Alkaloid ◽  
New Type

The isolation of the novel pentacyclic base megastachine (1), representative of a new type of Lycopodium alkaloid, is reported. Its structure has been determined by X-ray diffraction analysis.

Ten-Vertex Polyhedral Monocarbaborane Chemistry. The Novel High-Yield Formation of the Ten-Vertex closo Compound [6-(PMe2Ph)-closo-1-CB9H9] from the Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11]

1993 ◽  
Vol 58 (12) ◽  
pp. 2924-2935 ◽  
Author(s):  
Jane H. Jones ◽  
Bohumil Štíbr ◽  
John D. Kennedy ◽  
Mark Thornton-Pett
Keyword(s):  
Nmr Spectroscopy ◽  
Diffraction Analysis ◽  
High Yield ◽  
Monoclinic Space Group ◽  
The Novel ◽  
X Ray Diffraction ◽  
Metal Centre ◽  
X Ray ◽  
Yield Formation ◽  
Boiling Toluene

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.

scholarly journals Insertion of Phosphenium Ions into a Bicyclo[1.1.0]Tetraphosphabutane Iron Complex

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3920
Author(s):  
Martin Weber ◽  
Gábor Balázs ◽  
Alexander V. Virovets ◽  
Eugenia Peresypkina ◽  
Manfred Scheer
Keyword(s):  
Diffraction Analysis ◽  
Room Temperature ◽  
31P Nmr ◽  
Spectroscopic Studies ◽  
Iron Complex ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phosphenium Ions

By reacting [{Cp‴Fe(CO)2}2(µ,η1:1-P4)] (1) with in situ generated phosphenium ions [Ph2P][A] ([A]− = [OTf]− = [O3SCF3]−, [PF6]−), a mixture of two main products of the composition [{Cp‴Fe(CO)2}2(µ,η1:1-P5(C6H5)2)][PF6] (2a and 3a) could be identified by extensive 31P NMR spectroscopic studies at 193 K. Compound 3a was also characterized by X-ray diffraction analysis, showing the rarely observed bicyclo[2.1.0]pentaphosphapentane unit. At room temperature, the novel compound [{Cp‴Fe}(µ,η4:1-P5Ph2){Cp‴(CO)2Fe}][PF6] (4) is formed by decarbonylation. Reacting 1 with in situ generated diphenyl arsenium ions gives short-lived intermediates at 193 K which disproportionate at room temperature into tetraphenyldiarsine and [{Cp‴Fe(CO)2}4(µ4,η1:1:1:1-P8)][OTf]2 (5) containing a tetracyclo[3.3.0.02,7.03,6]octaphosphaoctane ligand.

Luciduline: a unique type of Lycopodium alkaloid

1968 ◽  
Vol 46 (23) ◽  
pp. 3631-3642 ◽  
Author(s):  
W. A. Ayer ◽  
N. Masaki ◽  
D. S. Nkunika
Keyword(s):  
Mass Spectra ◽  
X Ray Diffraction ◽  
Complete Structure ◽  
Unique Type ◽  
X Ray ◽  
Physical Evidence ◽  
Weak Bases ◽  
Lycopodium Alkaloid ◽  
New Type

The isolation and determination of the structure of luciduline, C13H21ON, an alkaloid present among the weak bases of Lycopodium lucidulum Michx, is described. Chemical and physical evidence which suggests structure 9 for luciduline is presented. An X-ray diffraction study on O-p -bromobenzoyl-dihydroluciduline confirmed this hypothesis and defined the stereochemistry of the methyl group at C-8. The complete structure of luciduline, including absolute configuration, is thus represented by 1. A possible mode of biosynthesis of luciduline, which is a new type of Lycopodium alkaloid, is discussed. The mass spectra of luciduline and some of its derivatives are interpreted in terms of structure 1.

Supramolecular architecture in azaheterocyclic phosphonates. III. Structures of an ethyl phosphonamidate and an ethyl phosphonate

2018 ◽  
Vol 74 (8) ◽  
pp. 907-916
Author(s):  
Anna Pietrzak ◽  
Jakub Modranka ◽  
Jakub Wojciechowski ◽  
Tomasz Janecki ◽  
Wojciech M. Wolf
Keyword(s):  
Hydrogen Bond ◽  
Diffraction Analysis ◽  
Crystal Packing ◽  
Supramolecular Architecture ◽  
The Novel ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hirshfeld Surfaces ◽  
Independent Molecules

The novel crystal structures of ethyl (S)-P-(4-oxo-4H-benzo[4,5]thiazolo[3,2-a]pyrimidin-3-yl)-N-[(R)-1-phenylethyl]phosphonamidate, C20H20N3O3PS, I, and diethyl (4-isopropyl-2-oxo-3,4-dihydro-2H-benzo[4,5]thiazolo[3,2-a]pyrimidin-3-yl)phosphonate, C18H25N2O4PS, II, were characterized by X-ray diffraction analysis. The crystal packing of I is dominated by two infinite stacks composed of symmetry-independent molecules linked by distinctively different hydrogen-bond systems. The structure of II shows a ladder packing topology similar to those observed in related phosphorylated azaheterocycles. Structural studies are supplemented by calculations on the interactions stabilizing the molecular assemblies using the PIXEL method. Additionally, fingerprint plots derived from the Hirshfeld surfaces were generated for each structure to characterize the crystal packing arrangements in detail. The aromaticities of the heterocyclic moieties have been investigated using HOMA and HOMHED parametrization and compared with structures reported previously.

3-pyridiniumindolyl-2-thiolates - New type of functionalized indoles

1988 ◽  
Vol 53 (8) ◽  
pp. 1761-1769 ◽  
Author(s):  
Jozef Gonda ◽  
Pavol Kristian
Keyword(s):  
Diffraction Analysis ◽  
Dimethyl Sulfoxide ◽  
Mass Spectra ◽  
Sodium Ethoxide ◽  
Sodium Hydride ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
New Type ◽  
C Nmr

2-Bromomethylphenyl isothiocyanate (I) reacts with pyridines to give 2-isothiocyanatobenzylpyridinium bromides II. Deprotonation of these compounds with sodium ethoxide in ethanol of sodium hydride in dimethyl sulfoxide afforded novel type of functionalized indoles, 3-pyridiniumindolyl-2-thiolates. Reaction of II with KOH or KCN gave products of addition to the NCS group VII and VIII, respectively. Structure of the obtained compounds was proven by IR, 1H NMR, 13C NMR, and mass spectra and was confirmed by X-ray diffraction analysis of 3-pyridiniumindolyl-2-thiolate.

Synthesis of 3-Aryl-3,4-Dihydroquinazolin-2(1H)-Ones with the Aid of Low-Valent Titanium Reagent (TiCl4-Sm)

2007 ◽  
Vol 2007 (9) ◽  
pp. 545-547 ◽  
Author(s):  
Daqing Shi ◽  
Guolan Dou ◽  
Zheng-Yi Li
Keyword(s):  
Diffraction Analysis ◽  
Elemental Analysis ◽  
The Novel ◽  
X Ray Diffraction ◽  
Facile Synthesis ◽  
X Ray ◽  
H Nmr ◽  
Low Valent

A short and facile synthesis of a series of 3-aryl-3,4-dihydroquinazolin-2(1H)-ones was accomplished in good yields via the novel reductive cyclisation of 2-nitrobenzylamines with bis(trichloromethyl)carbonate (triphosgene) promoted by TiCl4/Sm system. The structures of the products were characterised by IR, 1H NMR and elemental analysis and the structure of 3a was confirmed by X-ray diffraction analysis.

Anthosterones A and B, ring A contracted steroids from the sponge Anthoracuata graceae

1988 ◽  
Vol 66 (5) ◽  
pp. 1173-1178 ◽  
Author(s):  
Mark Tischler ◽  
Stephen W. Ayer ◽  
Raymond J. Andersen ◽  
John F. Mitchell ◽  
Jon Clardy
Keyword(s):  
Spectral Analysis ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Spectral Data ◽  
Model Compound ◽  
X Ray Diffraction ◽  
Steroid Nucleus ◽  
X Ray ◽  
New Type

Four new steroids, anthosterone A (5), anthosterone B (6), and the Δ4-3,6-diketo steroids 7 and 8, have been isolated from the sponge Anthoarcuata graceae. The structures of anthosterones A (5) and B (6) were deduced from their spectral data and verified via single crystal X-ray diffraction analysis on 5. The proposed structures for steroids 7 and 8 were based on spectral analysis and confirmed by synthesis of a model compound 12. Anthosterones A and B represent the first examples of a new type of ring A contraction in a steroid nucleus.

Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

2003 ◽  
Vol 218 (5) ◽  
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören
Keyword(s):  
Crystal Structure ◽  
Inclusion Complex ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

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