(-)-Strempeliopine, stereoselective total synthesis and the determination of absolute configuration

A synthesis of (±)-strempeliopine (II) is described, the key step of which is the stereoselective reductive rearrangement of 18-methylene-1,2-dehydroaspidospermidine (XI). The absolute configuration of the natural (-)-base II was determined as (2S, 7R, 20R, 21R) on the basis of its synthesis from (+)-18-methylenevincadifformine (XVII) the configuration of which was derived from a comparison of circular dichroism properties of bases with a β-anilinoacrylate chromophore. The biogenesis of the alkaloids of the schizozygane type is discussed.

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Determination of the Absolute Configuration of Perylene Quinone-Derived Mycotoxins by Measurement and Calculation of Electronic Circular Dichroism Spectra and Specific Rotations

Chemistry - A European Journal ◽

10.1002/chem.201402567 ◽

2014 ◽

Vol 20 (36) ◽

pp. 11463-11470 ◽

Cited By ~ 9

Author(s):

Joachim Podlech ◽

Stefanie C. Fleck ◽

Manfred Metzler ◽

Jochen Bürck ◽

Anne S. Ulrich

Keyword(s):

Circular Dichroism ◽

Absolute Configuration ◽

Circular Dichroism Spectra ◽

Electronic Circular Dichroism ◽

The Absolute ◽

Circular Dichroïsm

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Determination of absolute configuration using vibrational circular dichroism spectroscopy: phenyl glycidic acid derivatives obtained via asymmetric epoxidation using oxone and a keto bile acid

Tetrahedron Asymmetry ◽

10.1016/j.tetasy.2005.06.035 ◽

2005 ◽

Vol 16 (15) ◽

pp. 2653-2663 ◽

Cited By ~ 25

Author(s):

Frank J. Devlin ◽

Philip J. Stephens ◽

Olga Bortolini

Keyword(s):

Circular Dichroism ◽

Bile Acid ◽

Absolute Configuration ◽

Circular Dichroism Spectroscopy ◽

Vibrational Circular Dichroism ◽

Asymmetric Epoxidation ◽

Determination Of Absolute Configuration ◽

Circular Dichroïsm

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Absolute configuration determination of theanti-head-to-head photocyclodimer of anthracene-2-carboxylic acid through cocrystallization withL-prolinol

Acta Crystallographica Section C Crystal Structure Communications ◽

10.1107/s0108270113028461 ◽

2013 ◽

Vol 69 (11) ◽

pp. 1411-1413 ◽

Cited By ~ 3

Author(s):

Yuko Kawanami ◽

Hidekazu Tanaka ◽

Jun-ichi Mizoguchi ◽

Nobuko Kanehisa ◽

Gaku Fukuhara ◽

...

Keyword(s):

Crystal Structure ◽

Circular Dichroism ◽

Carboxylic Acid ◽

Absolute Configuration ◽

Void Space ◽

Circular Dichroism Spectra ◽

The Absolute ◽

Circular Dichroïsm ◽

Hydrogen Bonded

The absolute configuration has been established of the enantiopureanti-head-to-head cyclodimer of anthracene-2-carboxylic acid (AC) cocrystallized with L-propinol and dichloromethane [systematic name: (S)-2-(hydroxymethyl)pyrrolidin-1-ium (5R,6S,11R,12S)-8-carboxy-5,6,11,12-tetrahydro-5,12:6,11-bis([1,2]benzeno)dibenzo[a,e][8]annulene-2-carboxylate dichloromethane monosolvate], C5H12NO+·C30H19O4−·CH2Cl2. In the crystal structure, the AC dimer interacts with L-prolinol through a nine-membered hydrogen-bonded ring [R22(9)], while the dichloromethane molecule is incorporated to fill the void space. The absolute configuration determined in this study verifies a recent assignment made by comparing theoreticalversusexperimental circular dichroism spectra.

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