Transformation of the cyclohexane ring to the cyclopentane fragment of biologically active compounds

• Natalya Akhmetdinova,
• Ilgiz Biktagirov and
• Liliya Kh. Faizullina

Beilstein J. Org. Chem. 2025, 21, 2416–2446, doi:10.3762/bjoc.21.185

• objects for investigating the possibility of using them in the synthesis of compounds of iridoid topology. Iridoids belong to the class of terpenoids and are secondary metabolites of plants, as well as multi-tasking objects [5][17][18]. Studies on the pharmacological properties of iridoids have shown

Three new trixane glycosides obtained from the leaves of Jungia sellowii Less. using centrifugal partition chromatography

• Luíse Azevedo,
• Larissa Faqueti,
• Marina Kritsanida,
• Antonia Efstathiou,
• Despina Smirlis,
• Gilberto C. Franchi Jr,
• Grégory Genta-Jouve,
• Sylvie Michel,
• Louis P. Sandjo,
• Raphaël Grougnet and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2016, 12, 674–683, doi:10.3762/bjoc.12.68

• iridoid derivatives [31], and diterpene glycosides [32]. This technique was for the first time used with Jungia extracts. Elucidation of the compounds Compound 1 was obtained as colorless gum. The molecular formula C21H30O8 was determined from its ESI–HRMS spectrum which gave the cationic ion peak [M + H

Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part II: Iridomyrmecins

• Robert Hilgraf,
• Nicole Zimmermann,
• Lutz Lehmann,
• Armin Tröger and
• Wittko Francke

Beilstein J. Org. Chem. 2012, 8, 1256–1264, doi:10.3762/bjoc.8.141

• (4S,4aR,7S,7aR)-iridomyrmecin of 95–97% ee and stereochemically pure (4S,4aS,7R,7aS)-iridomyrmecin as a minor component. Keywords: Alloxysta victrix; identification; iridoid; stereoselective synthesis; trans-fused iridomyrmecin; Introduction In the course of our studies on volatile signals of the

• chiral centers complicates a stereoselective synthesis despite the small size of the molecule. Several methods have been published for the preparation of optically active cis-fused bicyclic iridoid lactones [7][8][9][10], whereas only a few syntheses of trans-fused ring systems have been reported [11

• iridomyrmecins with corresponding data of the volatile substances Y and Z – which are present in pentane extracts of heads of Alloxysta victrix – allowed their unambiguous identification as trans-fused iridomyrmecins. Coupled GC/MS analysis using FFAP as the stationary phase revealed the natural iridoid lactones

Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part I: Dihydronepetalactones

• Nicole Zimmermann,
• Robert Hilgraf,
• Lutz Lehmann,
• Daniel Ibarra and
• Wittko Francke

Beilstein J. Org. Chem. 2012, 8, 1246–1255, doi:10.3762/bjoc.8.140

• released by the endohyperparasitoid wasp Alloxysta victrix contain the enantiomerically pure trans-fused (4R,4aR,7R,7aS)-dihydronepetalactone as a minor component, showing an unusual (R)-configured stereogenic center at position 7. Keywords: Alloxysta victrix; identification; iridoid; stereoselective

• few approaches specifically aiming at the synthesis of trans-fused iridoid lactones have been published. Starting from (S)-pulegone (9) or its enantiomer, Wolinsky [20][21] described a route to this group of iridoids that can be applied to synthesize pure stereoisomers of dihydronepetalactones as well

• dihydronepetalactones, starting from pure enantiomers of limonene. Our approach is also superior to that starting from optically active carvone that yields the starting material for the synthesis of trans-fused iridoid lactones only as a byproduct [15]. Identification of a trans-fused dihydronepetalactone in the