scholarly journals Stereoselective Convergent Synthesis of Carbon Skeleton of Cotylenin A Aglycone

Synthesis ◽  
2021 ◽  
Author(s):  
Kazuyuki Sugita ◽  
Motoi Kuwabara ◽  
Ami Matsuo ◽  
Shogo Kamo ◽  
Akinobu Matsuzawa
Keyword(s):  
Single Crystal ◽  
Aldol Reaction ◽  
Coupling Reaction ◽  
Carbon Skeleton ◽  
Convergent Synthesis ◽  
X Ray ◽  
Related Compounds

AbstractIn this paper, the synthesis of the carbon skeleton of cotylenin A aglycone is described. The key reactions, including an intramolecular aldol reaction, an aldol coupling reaction, and a ring-closing meta­thesis, allow for the effective and stereoselective access to the carbon skeleton of cotylenin A aglycone. The stereochemistry was confirmed by single-crystal X-ray crystallographic analyses of related compounds.

The Preparation of 1,2-Bis(2,2′:6′,2′′-Terpyridin-4′yl)Ethanone: The First Example of 4′-Terpyridyls Unsymmetrically Linked by a Functionalized Two-Carbon Chain

2004 ◽  
Vol 57 (7) ◽  
pp. 689 ◽  
Author(s):  
Zhi-Long Chen ◽  
Ronald N. Warrener ◽  
Douglas N. Butler
Keyword(s):  
Sulfuric Acid ◽  
Hydrochloric Acid ◽  
Single Crystal ◽  
Coupling Reaction ◽  
Carbon Chain ◽  
Sodium Cyanide ◽  
Starting Material ◽  
X Ray ◽  
Concentrated Sulfuric Acid ◽  
Single Crystal Analysis

1,2-Bis(2,2′:6′,2′′-terpyridin-4′yl)ethanone 7, an unsymmetrically linked bis-tridentatate ligand, was prepared by treatment of 4′-cyanomethylterpyridine 10 (RT, overnight) or 4′-(methoxycarbonylmethyl)terpyridine 11 (60°C, 7 h) with concentrated hydrochloric acid. These conversions, which involved an unprecedented homo-coupling reaction, are discussed with the structure of 7 being confirmed by X-ray single crystal analysis. The nitrile starting material 10 was prepared by reaction of the mesylate 9, derived from the known 4′-hydroxymethylterpyridine 8 with sodium cyanide, while ester 11 was prepared by reaction of 10 with methanol in the presence of concentrated sulfuric acid.

gem-Diol and Hemiacetal Forms in Formylpyridine and Vitamin-B6-Related Compounds: Solid-State NMR and Single-Crystal X-ray Diffraction Studies

2016 ◽  
Vol 120 (39) ◽  
pp. 7778-7785 ◽  
Author(s):  
Ayelén Florencia Crespi ◽  
Daniel Vega ◽  
Ana Karina Chattah ◽  
Gustavo Alberto Monti ◽  
Graciela Yolanda Buldain ◽  
...  
Keyword(s):  
Solid State ◽  
Single Crystal ◽  
Solid State Nmr ◽  
Vitamin B6 ◽  
X Ray Diffraction ◽  
X Ray ◽  
Related Compounds

Oxidative coupling of cycloalkanones with 3-(pyridin-2-yl)-1,2,4-triazinone coordinated to Pd(II)

2018 ◽  
Vol 73 (8) ◽  
pp. 583-587
Author(s):  
Mustafa M. El-Abadelah ◽  
Firas F. Awwadi ◽  
Hamdallah A. Hodali ◽  
Rasha S. Rawajfeh ◽  
Monther S. Zreid ◽  
...  
Keyword(s):  
Single Crystal ◽  
Spectral Data ◽  
Oxidative Coupling ◽  
Coupling Reaction ◽  
X Ray ◽  
X Ray Crystallography ◽  
Square Planar ◽  
Pd Complexes ◽  
Palladium Ion

AbstractDichloro[3-(pyridin-2-yl)-1,2,4-triazinone]Pd(II) undergoes oxidative C–C coupling reaction with cyclopentanone and cyclohexanone at 110°C to yield the respective Pd complexes, chloro[1-(4-chlorophenyl)-5-(2-hydroxycyclopent-1-enyl)-3-(pyridin-2-yl)-1,2,4-triazin-6(1H)-one]palladium(II) (3) and chloro[1-(4-chlorophenyl)-5-(2-hydroxycyclohex-1-enyl)-3-(pyridin-2-yl)-1,2,4-triazin-6(1H)-one]palladium(II) (4). The structures of both complexes are supported by spectral data and confirmed by single-crystal X-ray crystallography. The molecules 3 and 4 stack to form tunnel structures, whilst the geometry around the palladium ion is square planar.

Synthesis and Biological Evaluation of Some Enantiomerically Pure C8c - C15 Monoseco Analogues of the Phenanthroquinolizidine-Type Alkaloids Cryptopleurine and Julandine

2008 ◽  
Vol 61 (7) ◽  
pp. 506 ◽  
Author(s):  
Magne O. Sydnes ◽  
Anna Bezos ◽  
Christopher Burns ◽  
Irma Kruszelnicki ◽  
Christopher R. Parish ◽  
...  
Keyword(s):  
Single Crystal ◽  
Building Blocks ◽  
Biological Evaluation ◽  
Enantiomerically Pure ◽  
X Ray ◽  
System 1 ◽  
Synthesis And Biological Evaluation ◽  
Related Compounds

A series of enantiomerically pure C8c–C15 monoseco analogues, 23–30, of the alkaloids cryptopleurine (1) and julandine (2) have been prepared using cinnamyl chloride 37 and (S)- or (R)-2-methylpiperidine as key building blocks. Two related compounds, 31 and 32, have also been synthesized. Each of these analogues has been subjected to various biological evaluations and most of them show dramatically reduced cytotoxicity compared with parent system 1. Nevertheless, they are potent anti-angiogenic agents. The formation and single-crystal X-ray analysis of the spirocyclic dienone 54, a by-product arising from attempts to prepare analogue 32, is also described.

scholarly journals First Total Synthesis of Varioxiranol A

Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 862 ◽  
Author(s):  
Angelika Lásiková ◽  
Jana Doháňošová ◽  
Mária Štiblariková ◽  
Martin Parák ◽  
Ján Moncol ◽  
...  
Keyword(s):  
Total Synthesis ◽  
Single Crystal ◽  
Absolute Configuration ◽  
Coupling Reaction ◽  
X Ray ◽  
Synthetic Strategy

The paper describes the first total synthesis of natural varioxiranol A by chiral pool approach and confirmation of its absolute configuration by single-crystal X-ray analysis. The target varioxiranol A and its 4-epimer were obtained after 10 steps from single and available chiral source 1,2-O-isopropylidene-d-glyceraldehyde in an overall yield of 10% and 6%, respectively. A synthetic strategy based on the Julia–Kocieński coupling reaction between aromatic sulfone and corresponding aldose derivative makes it possible to prepare other interesting polyketide derivatives (varioxiranols B-G, varioxirane, varioxiranediols).

Complete X-ray single-crystal structure determination and Raman spectrum of NH4[C(CN)3]

2017 ◽  
Vol 72 (7) ◽  
pp. 517-521
Author(s):  
Olaf Reckeweg ◽  
Armin Schulz ◽  
Francis J. DiSalvo
Keyword(s):  
Crystal Structure ◽  
Raman Spectrum ◽  
Single Crystal ◽  
Single Crystals ◽  
Structure Determination ◽  
Title Compound ◽  
Single Crystal Structure ◽  
Crystal Structure Determination ◽  
X Ray ◽  
Related Compounds

AbstractThe crystal structure of NH4[C(CN)3] has been determined via X-ray single-crystal methods at 203(2) K corroborating earlier results. Additionally, the hydrogen positions have been determined and the Raman spectrum of the title compound recorded on single crystals. The spectroscopic results are compared to those for related compounds.

Two- and three-dimensional β,β’-N-heterocycle fused porphyrins: concise construction, singlet oxygen production and electro-catalytic hydrogen evolution reaction

2021 ◽  
Author(s):  
Jianxin Song ◽  
Yan Fan ◽  
Zhiming Zeng ◽  
Hui Shu ◽  
Mingbo Zhou ◽  
...  
Keyword(s):  
Single Crystal ◽  
Hydrogen Evolution Reaction ◽  
Three Dimensional ◽  
Coupling Reaction ◽  
Crystallographic Analysis ◽  
Oxygen Production ◽  
X Ray ◽  
Palladium Catalyzed ◽  
Catalytic Hydrogen ◽  
Catalytic Hydrogen Evolution

A powerful and concise synthesis of two- and three-dimensional β,β’-N-heterocycle fused porphyrins by palladium-catalyzed C-N coupling reaction of bromoporphyrins with arylamines has been demonstrated. Single crystal X-ray crystallographic analysis revealed...

Die Kristallstrukturen der Eisen- und Cobalt-Hexacyanokomplexe Rb2LiM(CN)6 und Rb2NaM(CN)6 / The Crystal Structures of the Iron- and Cobalt-Hexacyanocomplexes Rb2LiM(CN)6 and Rb2NaM(CN)6

1996 ◽  
Vol 51 (6) ◽  
pp. 826-831 ◽  
Author(s):  
Stefan Peschel ◽  
Werner Paulus ◽  
Dietrich Babel
Keyword(s):  
Neutron Diffraction ◽  
Single Crystal ◽  
Crystal Structures ◽  
Coordination Polyhedra ◽  
X Ray ◽  
Cyano Complexes ◽  
Related Compounds ◽  
Ray Methods

Abstract The crystal structures of four isotypic cyano complexes, belonging to the monoclinic type of cryolite (P21/n, Z = 2), were determined by single crystal X-ray methods and in one case also by neutron diffraction: Rb2LiFe(CN)6 (a = 717.3, b = 748.0, c = 1030.2 pm, β = 90.24°; Fe - C = 193.6, C - N = 114.5, Li - N = 227.0 pm), Rb,NaFe(CN)6 (a = 724.5, b = 772.5, c = 1055.2 pm, β = 90.39°; Fe - C = 193.9, C - N = 114.2, Na - N = 250.4 pm), Rb,LiCo(CN)6 (a = 715.5, b = 741.2, c = 1025.0 pm, β = 90.14°; Co - C = 189.6, C - N = 114.3, Li - N = 226.9 pm), Rb2NaCo(CN)6 (a = 722.5, b = 766.3, c = 1049.2 pm, β = 90.33°; Co - C = 189.9 (188.8), C - N = 113.4 (7/5.5), Na - N = 250.6 (249.6 pm). The irregular [RbN8l coordination polyhedra exhibit average distances close to Rb - N = 336 pm. Details are discussed and the results compared with those of related compounds

Zur Kristallchemie der Oxoplatinate. Eine neue Phase der Zusammensetzung Sr4-ϰNaϰPtO6 (ϰ = 0,33) / On the Crystal Chemistry of Oxoplatinates. A New Phase of the Composition Sr4-ϰNaϰPtO6 (ϰ = 0,33)

1994 ◽  
Vol 49 (5) ◽  
pp. 581-584 ◽  
Author(s):  
G. Tams ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Single Crystals ◽  
Crystal Chemistry ◽  
Space Group ◽  
X Ray ◽  
Group D ◽  
Related Compounds ◽  
New Phase ◽  
Trigonal Prismatic

Single crystals of Sr3.67Na0.33PtO6 were prepared by heating oxide mixtures in closed silver tubes and investigated by X-ray single crystal techniques. It crystallizes with trigonal symme­try, space group D63d-R3̅c (Nr. 167) with a = 9.6617, c = 11.6580 Å, Z = 6. Sr3.67Na0.33PtO6 belongs to the Sr4PtO6 type and is isotypic to K4CdCl6. One point position characterized by a trigonal prismatic O2- coordination is occupied by Na+ and Sr2+ statistically. The crystal structure is discussed with respect to the related compounds Sr3CuPtO6 and Ca3. 5Cu0.5PtO6.

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