7712-68-7Relevant academic research and scientific papers
Pheromone synthesis. Part 264: Synthesis of the core 3-oxabicyclo[3.3.0]octane structures of gomadalactones A, B and C, the components of the contact sex pheromone of the white-spotted longicorn beetle, Anoplophora malasiaca
Mori, Kenji
, p. 3387 - 3398 (2019/05/15)
The core bicyclic cyclopentanelactone structures of gomadalactones A, B and C with α-hydroxyketone system were synthesized from (R)-pulegone, employing deconjugation of an α,β-unsaturated lactone as the key step. Comparison of the CD spectra of the synthetic compounds with those of the natural products confirmed the absolute configuration of the natural pheromone components as proposed in 2007. X-ray crystallographic analysis of the model compound of gomadalactone B core structure was carried out.
Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part I: Dihydronepetalactones
Zimmermann, Nicole,Hilgraf, Robert,Lehmann, Lutz,Ibarra, Daniel,Francke, Wittko
scheme or table, p. 1246 - 1255 (2012/10/08)
Starting from the enantiomers of limonene, all eight stereoisomers of trans-fused dihydronepetalactones were synthesized. Key compounds were pure stereoisomers of 1-acetoxymethyl-2-methyl-5-(2-hydroxy-1-methylethyl)-1- cyclopentene. The stereogenic center of limonene was retained at position 4a of the target compounds and used to stereoselectively control the introduction of the other chiral centers during the synthesis. Basically, this approach could also be used for the synthesis of enantiomerically pure trans-fused iridomyrmecins. Using synthetic reference samples, the combination of enantioselective gas chromatography and mass spectrometry revealed that volatiles 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.
Enantioselective synthesis of the unnatural enantiomers of the fungal sesquiterpenoids acorenone and trichoacorenol
Brock, Nelson L.,Dickschat, Jeroen S.
experimental part, p. 5167 - 5175 (2011/10/09)
The volatiles released by several strains of Trichoderma fungi were collected using a closed-loop stripping apparatus and analysed by GC-MS. Most of the investigated strains released the two structurally related spirocyclic sesquiterpenoids trichoacorenol, previously identified in Trichoderma koningii (Huang et al., 1995), and acorenone. A new enantioselective synthesis of the enantiomer of the natural spirocyclic sesquiterpene acorenone and the first enantioselective synthesis of the related compound ent-trichoacorenol have been completed by a chiral-pool approach starting from (+)-(R)-pulegone using ring-closing metathesis as the key step. The absolute configuration of natural trichoacorenol from Trichoderma harzianum sp. 714 has been assigned by chiral GC-MS analysis and is the same as that in T. koningii. A new enantioselective synthesis of the unnatural enantiomers of the two spirocyclic sesquiterpenes acorenone and trichoacorenol has been accomplished from (+)-(R)-pulegone using ring-closing metathesis in a key step. The synthetic material has been used to determine the absolute configuration of trichoacorenol, the principal volatile component in headspace extracts of Trichoderma harzianum. Copyright
Total synthesis of citridone A
Miyagawa, Tomoko,Nagai, Keisuke,Yamada, Asami,Sugihara, Yoshinori,Fukuda, Takeo,Fukuda, Takashi,Uchida, Ryuji,Tomoda, Hiroshi,Omura, Satoshi,Nagamitsu, Tohru
supporting information; experimental part, p. 1158 - 1161 (2015/05/06)
The first total synthesis of citridone A has been achieved through regioselective intramolecular iodocyclization and regio-and stereoselective Pd(0)-catalyzed coupling as key reactions.(Figure Presented)
Terpenes and Terpene Derivatives, XXIX Synthesis and Olfactive Properties of (-)- and rac-Silphiperfol-5-en-3-ol and of Some Tris-nor Derivatives
Weyerstahl, Peter,Brendel, Joachim
, p. 669 - 678 (2007/10/02)
The new sesquiterpene alcohols silphiperfol-5-en-3-ol and the corresponding 7-epi compound (+)-1b, important constituents of the essential oil of Artemisia laciniata have been synthesized in 13 steps by starting from (R)-(+)-pulegone (6) in an overall yield of 8percent.The key reaction is the copper-catalyzed 1,4-Grignard addition of the iodo acetal 34 to the enone (+)-4 in the presence of TMSCl and TMEDA to give the silyl ether 38.Hydrolysis with spontaneous aldol cyclization and dehydration leads to the silphiperfolenones (+)-2a,b which are separable by flash chromatgraphy.The reduction with L-selectrideR gives the alcohols (-)-1a and (+)-1b which are identical in all physical properties with the isolated natural compound.With LiAlH4 the diastereoisomers 42a,b are formed.Olfactive evaluation of the isomers (-)-1a and (+)-1b has shown that the odor of the naturally occuring mixture of 1a,b with the descriptors woody, ambergris, slightly camphoraceous is correctly assigned. (-)-1a represents the more woody and camphoraceous, (+)-1b the more animal facette of ambergris.The odor of rac-1a,b, of the diasteroisomers 42a,b and of the ketones (+)-2a,b is also described as well as that of the tris-nor-silphiperfolene derivatives 29-31. Key Words: Artemisia laciniata / Sesquiterpene alcohols, tricyclic / Structure-odor correlation / (R)-(+)-Pulegone / 1,4-Grignard reaction
An efficient synthesis of the Prelog-Djerassi lactone methyl ester from (-)-trans-pulegenic acid
Hacini, Salih,Santelli, Maurice
, p. 7787 - 7792 (2007/10/02)
The (+)-Prelog-Djerassi lactone methyl ester 1 was obtained from trans-pulegenic acid 2 in seven steps in 22 % overall yield; three more steps from an unwanted diastereoisomer gave additionnal 5%.
Terpenic Acids by Cyclopentane Annulation of Exocyclic Dienes. Synthesis of Triquinane Portion of Retigeranic Acid
Hudlicky, Tomas,Short, Robert P.
, p. 1522 - 1527 (2007/10/02)
Tricyclic ester 5 has been prepared in 13 steps from (+)-pulegone.The key step in the synthesis of 5 involved the condensation of keto ester 15 with ethyl bromocrotonate under Reformatsky conditions to yield lactone 16 as one diastereomer.Either lithium diisopropylamine or 1,8-diazabicycloundec-7-ene was used to effect the elimination to the dienic acid 17, obtained as a mixture of diastereomers in an 80:20 ratio.Conditions were developed for the cyclopropanation of 18 in good isolated yields.The pyrolysis of 19 gave tricyclic ketone 20 in 50 percent yield.The 13C NMR data are provided for all relevant intermediates.The deoxygenation of this ketone provided ester 5.The structural and stereochemical assignments are based on data amassed previously on appropriate model compounds.Potential use of 5 in a convergent synthesis of retigeranic acid (3) is indicated.The concept of generality of this method in the context of total synthesis of other naturally occuring cyclopentene carboxylates is introduced.
